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Publications of the GREET Model Development and Applications. This document provides the title, authors, publication date, venue of availability, and a description of the content of each GREET model report, which are listed in chronological order.
Impact of the renewable Oxygenate Standard for Reformulated Gasoline on Ethanol Demand, Energy Use, and Greenhouse Gas Emissions
Kevin C. Stork and Margaret K. Singh
Venue of Availability:
http://greet.es.anl.gov/publication-oxy-standard
GREET 1.0 - Transportation Fuel Cycles Model: Methodology and Use
M. Wang
http://greet.es.anl.gov/publication-c4z3r4c2
This is the first report to document the development of the first GREET version with general simulation approaches of fuel-cycle analysis.
Fuel-Cycle Fossil Energy Use and Greenhouse Gas Emissions of Fuel Ethanol Produced from U.S. Midwest Corn
M. Wang, C. Saricks, M. Wu
http://greet.es.anl.gov/publication-oofq1amb
This is the first report to document key assumptions and results of corn-based ethanol simulated with the GREET model. The report documents different methods of dealing with co-products from corn ethanol plants. It is the first report to document detailed data and analysis of N2O emissions from cornfields. It is the first report to present Argonne's results on energy and GHG emissions by corn ethanol relative to petroleum gasoline
Effects of Fuel Ethanol Use on Fuel-Cycle Energy and Greenhouse Gas Emissions
M. Wang, C. Saricks, D. Santini
http://greet.es.anl.gov/publication-xf8nbkoc
This report presents updated results of energy use and GHG emissions of corn ethanol simulated with the GREET model. The report documents displacement ratios between co-products of corn ethanol and conventional animal feeds and inclusion of GHG effects of direct land use changes.
Transportation Fuel-Cycle Analysis: What Can the GREET Model Do?
http://greet.es.anl.gov/publication-sbq9lo5o
GREET 1.5 — Transportation Fuel-Cycle Model, Volume 2: Appendices of Data and Results
http://greet.es.anl.gov/publication-greet1p5_v2
This report is a revision to a previous Argonne National Laboratory report entitled GREET 1.0 — Transportation Fuel Cycles Model: Methodology and Use (dated June 1996). The 1996 report documented the methodologies, key assumptions, and results of the development and use of the first version of the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) fuel-cycle model developed at Argonne National Laboratory. Since then, the GREET 1.0 model has been significantly expanded and improved. The model has evolved into three modules (each comprising a series of versions): the first module covers fuelcycle energy and emissions of passenger cars and light-duty trucks (GREET 1.1, GREET 1.2, etc.); the second covers vehicle-cycle energy and emissions of passenger cars and light-duty trucks (GREET 2.1, GREET 2.2, etc.); and the third module covers fuel-cycle energy and emissions of heavy-duty trucks (gross vehicle weight over 8,500 pounds) (GREET 3.1, GREET 3.2, etc.). In September 1998, GREET 1.4 was released with a draft report documenting its development. The model was posted at Argonne's transportation website at www.transportation.anl.gov/ttrdc/publications/papers_reports/techassess/ta_papers.html, and the draft report was sent to reviewers for comment. Since then, significant revisions and expansions have been made to both the report and the model. The current version of the 1-series model is GREET 1.5. This report documents the development and use of GREET 1.5. It includes portions of the 1996 report that have few changes (e.g., the introduction and review of previous fuelcycle studies) to eliminate the need for readers to refer to the previous report. It also reflects reviewers' comments on the August 1998 draft report. This report is separated into two volumes. Volume 1 presents GREET 1.5 development and use and discussions of fuel-cycle energy and emission results for passenger cars. Volume 2, comprising four appendices, presents detailed fuel-cycle results for passenger cars, light-duty trucks 1, and light-duty trucks 2.
Technical Report: GREET 1.5 -- Transportation Fuel-Cycle Model - Volume 1: Methodology, Development, Use, and Results
http://greet.es.anl.gov/publication-20z8ihl0
This report thoroughly documents methodologies, key assumptions and their data sources, and results of fuel-cycle analysis for vehicle/fuel systems with the GREET model. It lays out calculations logistics for energy use and emissions of well-to-pump stages. It also presents results of several major fuel-cycle analysis studies available at that time. It is also the first report to present WTW results of all vehicle/fuel systems in the GREET model.
The Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) Model Version 1.5
http://greet.es.anl.gov/publication-h3k81jas
This document briefly outlines the model structure of GREET 1.5.
Technical Report: GREET 1.5 -- Transportation Fuel-Cycle Model - Volume 2: Appendixes of Data and Results
http://greet.es.anl.gov/publication-w1hsudgs
GREET 1.5 — Transportation Fuel-Cycle Model, Volume 1: Methodology, Development, Use, and Results
A Full-Fuel-Cycle Analysis of Energy and Emissions Impacts of Transportation Fuels Produced from Natural Gas
M. Wang, H. Huang
http://greet.es.anl.gov/publication-xfcbsvdv
This report documents the development of transportation fuel pathways based on natural gas and the results of these pathways. It presents fuel production technologies, key assumptions and their data sources, and results of natural gas-based fuel production pathways. This report reflects revisions of key assumptions regarding NG-based fuels in the GREET version at that time.
GREET 1.5a: Changes from GREET 1.5
http://greet.es.anl.gov/publication-ou0mj7gg
This memorandum documents changes from GREET1.5 to GREET1.5a.
Contribution of Feedstock and Fuel Transportation to Total Fuel-Cycle Energy Use and Emissions (abstract)
D. He, M. Wang
SAE, International Fuels & Lubricants Meeting & Exposition 2000-01-2976
http://greet.es.anl.gov/publication-qz6103oy
In recent years, various alternative fuels have been proposed and studied for application in motor vehicles. Consequently, fuel-cycle analyses have been conducted to evaluate their energy and emissions effects. In a typical fuel-cycle analysis, feedstock recovery; feedstock transportation and storage; fuel production; and fuel transportation, distribution, and storage are examined. The general belief is that transportation and storage of feedstocks and fuels have small impacts on fuel-cycle results. However, no thorough studies have been conducted to confirm or disprove this belief. Transportation of feedstocks and fuels via different transportation modes requires use of various fuels and generates air pollutant emissions. Storage of liquid and gaseous fuels is subject to fuel losses, which also lead to air pollutant emissions. In fuel-cycle analyses, while feedstock recovery and fuel production have been studied carefully, transportation and storage of feedstocks and fuels are often not studied in detail. As part of a comprehensive fuel-cycle analysis at Argonne National Laboratory, we recently began to characterize transportation modes for different feedstock types, fuel types, production locations, and consumption locations. We collected data on the energy intensities of various transportation modes and the distances traveled for given feedstocks and fuels. We included five transportation modes - ocean tanker, barge, truck, rail, and pipeline - for various feedstocks and fuels. On the basis of the collected data, we estimated energy use and emissions associated with transportation and storage of gasoline, diesel, compressed natural gas, liquefied natural gas, liquefied petroleum gas, methanol, ethanol, gaseous and liquid hydrogen, and Fischer-Tropsch diesel. Our assessment indicates that, in some cases, transportation, storage, and distribution (T&S&D) can make a significant contribution to total fuel-cycle energy use and emissions for transportation fuels. For example, nitrogen oxide (NOx) emissions from T&S&D of gasoline, diesel, liquefied petroleum gas, dimethyl ether, Fischer-Tropsch diesel, and ethanol can comprise over 50% of total upstream emissions. Moreover, when fuel losses are taken into account, T&S&D can contribute over 60% of upstream VOC emissions for gasoline, diesel, liquefied petroleum gas, dimethyl ether, Fischer-Tropsch diesel, and methanol.
Corn-Based Ethanol Does Indeed Achieve Energy Benefits
M. Wang, D. Santini
ECO: Ethanol, Climate Change, Oil Reduction
http://greet.es.anl.gov/publication-gnop85vp
We conducted a series of detailed analyses on energy and emission impacts of corn ethanol from 1997 through 1999. During our analyses, we researched improvements in energy intensity of corn farming and ethanol production by studying publicly available data and by contacting USDA, experts in the Midwestern farming and meat production communities, and ethanol plant designers and operators. Our research showed that corn productivity (defined as corn yield per unit of chemical input) increased by 30% between the early 1970s and mid-1990s. We also found that energy intensity of ethanol production (defined as energy use in ethanol plants per unit of ethanol produced) decreased by about 40% between the mid-1980s and late 1990s.
Fuel-Cycle Emissions for Conventional and Alternative-Fuel Vehicles: An Assessment of Air Toxics
J. Winebrake, D. He, M. Wang
http://greet.es.anl.gov/publication-qmanmyv9
This report provides information on Argonne's efforts to use the GREET model to estimate air toxics emissions. GREET was modified to account for the following important toxic pollutants: acetaldehyde, benzene, 1,3-butadiene, and formaldehyde. This is the first to consider fuel-cycle emissions of these pollutants for alternative transportation fuels and advanced vehicle technologies. Through this study, an air toxics version of the GREET model was developed.
GM Study: Well-to-Wheel Energy Use and Greenhouse Gas Emissions of Advanced Fuel/Vehicle Systems - North American Analysis - Volume 1: Executive Summary Report
J. Wallace, M. Wang, T. Weber, A. Finizza
http://greet.es.anl.gov/publication-3plz9fyi
This report documents work conducted by several organizations (including Argonne) where GREET was used to examine energy and GHG emission effects of over 100 vehicle/fuel systems. Through this effort, the stochastic simulations feature was developed for the GREET model. In addition, petroleum refining efficiencies were revised in GREET based on data from three petroleum refining studies. WTP energy efficiencies in GREET were revised through this effort.
GM Study: Well-to-Wheel Energy Use and Greenhouse Gas Emissions of Advanced Fuel/Vehicle Systems - North American Analysis - Appendix A: Probability Distribution Functions
http://greet.es.anl.gov/publication-d4f8x465
Development and Use of GREET 1.6 Fuel-Cycle Model for Transportation Fuels and Vehicle Technologies
http://greet.es.anl.gov/publication-3bjc9gly
This report documents new pathways, including petroleum to crude naphtha, NG to naphtha via the Fischer-Tropsch process, and electricity to gaseous hydrogen and liquid hydrogen via electrolysis, and key results of GREET 1.6. This was the first GREET version to have a graphic user interface that interacted with the spreadsheet and to incorporate uncertainty analysis of the fuel pathways. Also, in previous GREET versions, energy use and emissions from transporting energy feedstocks and fuels were simulated by using energy efficiencies as inputs to different transportation activities-similar to simulations of feedstock and fuel production activities. In the new version, transportation-related activities are simulated by using input parameters, such as transportation modes, transportation distances, energy use intensities for various transportation modes, and other factors.
GM Study: Well-to-Wheel Energy Use and Greenhouse Gas Emissions of Advanced Fuel/Vehicle Systems - North American Analysis - Appendix B: Complete Well-to-Tank Results
http://greet.es.anl.gov/publication-4tv5yxfx
GM Study: Well-to-Wheel Energy Use and Greenhouse Gas Emissions of Advanced Fuel/Vehicle Systems - North American Analysis - Volume 3: Transportation Fuels
http://greet.es.anl.gov/publication-wft2tv3v
GM Study: Well-to-Wheel Energy Use and Greenhouse Gas Emissions of Advanced Fuel/Vehicle Systems - North American Analysis - Volume 2: Advanced Fuel/Vehicle Systems
http://greet.es.anl.gov/publication-bbe1lqj9
The Energy Balance of Corn Ethanol: An Update
H. Shapouri, J. Duffield, M. Wang
http://greet.es.anl.gov/publication-5dfmot4h
Studies conducted since the late 1970s have estimated the net energy value (NEV) of corn ethanol. However, variations in data and assumptions used among the studies have resulted in a wide range of estimates. This study identifies the factors causing this wide variation and develops a more consistent estimate. We conclude that the NEV of corn ethanol has been rising over time due to technological advances in ethanol conversion and increased efficiency in farm production. We show that corn ethanol is energy efficient as indicated by an energy output:input ratio of 1.34.
Energy and Greenhouse Gas Emissions Effects of Fuel Ethanol
http://greet.es.anl.gov/publication-pctkd1qm
Soil Carbon Changes for Bioenergy Crops
D. Andress
http://greet.es.anl.gov/publication-rfihxb2h
This report details the characterization of the soil carbon sequestration for three bioenergy crops (switchgrass, poplars, and willows) for use in the GREET model. In addition, this report documents methodologies, key issues, and data needs in addressing soil carbon from land use changes caused by biofuel production in the context of a life-cycle analysis. Bioenergy crops, which displace fossil fuels when used to produce ethanol, bio-based products, and/or electricity, have the potential to further reduce atmospheric carbon levels by building up soil carbon levels, especially when planted on lands where these levels have been reduced by intensive tillage. A three-step process is used to conduct this study. First, the results of an economic analysis were used to determine crop yields, geographic locations for bioenergy crop production and land use changes. Next, a soil carbon model was used to estimate regional soil carbon changes on a per hectare basis over time, based on the regional yield and land use data calculated from the economic analysis. Finally, the data from the first two steps were combined to calculate the soil changes per unit of biomass as a function of time. In addition, the regional data was aggregated to make a national estimate. These results were applied to the methodology used in GREET to assign carbon changes to a unit of biomass (grams of carbon dioxide per dry ton of biomass) by calculating the total soil carbon changes over the life of the bioenergy crop farm and divide the resulting value by the total biomass production during that period.
Fuel Choices for Fuel-Cell Vehicles: Well-to-Wheels Energy and Emission Impacts
http://greet.es.anl.gov/publication-yhbzjgxn
Fuel Choices for Fuel-Cell Vehicles: Well-to-Wheels Energy and Emission Impacts (abstract)
Journal of Power Sources Volume 112 (2002): pp. 307-321
http://greet.es.anl.gov/publication-vmuujx18
Because of their high energy efficiencies and low emissions, fuel-cell vehicles are undergoing extensive research and development. While hydrogen will likely be the ultimate fuel to power fuel-cell vehicles, because of current infrastructure constraints, hydrogen-carrying fuels are being investigated as transitional fuel-cell fuels. A complete well-to-wheels evaluation of fuel-cell vehicle energy and emission effects that examines (1) energy feedstock recovery and transportation; (2) fuel production, transportation, and distribution; and (3) vehicle operation must be conducted to assist decision makers in selecting the fuel-cell fuels that achieve the greatest energy and emission benefits. A fuel-cycle model developed at Argonne National Laboratory - called the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model - was used to evaluate well-to-wheels energy and emission impacts of various fuel-cell fuels. The results show that different fuel-cell fuels can have significantly different energy and greenhouse gas emission effects. Therefore, if fuel-cell vehicles are to achieve the envisioned energy and emission reduction benefits, pathways for producing the fuels that power them must be carefully examined.
Benefits and Costs of Hydrogen Fuels
M. Wang and M. Mintz
http://greet.es.anl.gov/publication-gkhuq2ro
Well-to-Wheels Energy and Emission Impacts of Vehicle/Fuel Systems
http://greet.es.anl.gov/publication-ea30hyon
Fuel-Cycle Energy and Greenhouse Emission Impacts of Fuel Ethanol
http://greet.es.anl.gov/publication-kkjvioz3
Well-to-Wheels Energy Use, Greenhouse Gas Emissions, and Criteria Pollutant Emissions -- Hybrid Electric and Fuel-Cell Vehicles
http://greet.es.anl.gov/publication-6vm6j7ll
Fuel-Cycle Energy and Emission Impacts of Ethanol-Diesel Blends in Urban Buses and Farming Tractors
M. Wang, C. Saricks, H. Lee
http://greet.es.anl.gov/publication-0kvjl6mv
This report documents WTW analysis of diesel and ethanol blends for use in urban buses and farming tractors. Through this study, energy use in fertilizer plants is thoroughly examined. Also, N2O emissions from cornfields are updated. Both are reflected in the GREET version developed at that time.
Allocation of Energy Use in Petroleum Refineries to Petroleum Products: Implications for Life-Cycle Energy Use and Emission Inventory of Petroleum Transportation Fuels
M. Wang, H. Lee, J. Molburg
The International Journal of Life Cycle Assessment, Volume 9, Number 1, 34-44
http://greet.es.anl.gov/publication-1c49xpjg
Studies to evaluate the energy and emission impacts of vehicle/fuel systems have to address allocation of the energy use and emissions associated with petroleum refineries to various petroleum products because refineries produce multiple products. The allocation is needed in evaluating energy and emission effects of individual transportation fuels. Allocation methods used so far for petroleum-based fuels (e.g., gasoline, diesel, and liquefied petroleum gas [LPG]) are based primarily on mass, energy content, or market value shares of individual fuels from a given refinery. The aggregate approach at the refinery level is unable to account for the energy use and emission differences associated with producing individual fuels at the next sub-level: individual refining processes within a refinery. The approach ignores the fact that different refinery products go through different processes within a refinery. Allocation at the subprocess level (i.e., the refining process level) instead of at the aggregate process level (i.e., the refinery level) is advocated by the International Standard Organization. In this study, we seek a means of allocating total refinery energy use among various refinery products at the level of individual refinery processes.
Might Canadian Oil Sands Promote Hydrogen Production Technologies for Transportation? - Greenhouse Gas Emission Implications of Oil Sands Recovery and Upgrading
R. Larsen, M. Wang, Y. Wu, A. Vyas, D. Santini, M. Mintz
http://greet.es.anl.gov/publication-hairbxzd
Well-to-Wheels Analysis of Energy Use and Greenhouse Gas Emissions of Hydrogen Produced with Nuclear Energy
Y. Wu, M. Wang, A. Vyas, D. Wade
http://greet.es.anl.gov/publication-xu5rq4um
Might Canadian Oil Sands Promote Hydrogen Production for Transportation? - Greenhouse Gas Emission Implications of Oil Sands Recovery and Upgrading (abstract)
World Resource Review, Volume 17, No.2: 220-242 (2005)
http://greet.es.anl.gov/publication-xsce3024
As world oil demand increases and OECD production has stagnated, oil price has moved above U.S. $50 a barrel. While worldwide conventional oil reserves continue to deplete, there are large amounts of "unconventional" oil reserves worldwide for recovery and upgrading. Among unconventional oil types, Canadian oil sands, primarily in Western Canadian Alberta province, have experienced large increases in production in recent years. This trend is predicted to continue to reach about 5 million barrels a day oil production by 2030. Recovery and upgrading of oil sands requires a large amount of steam and hydrogen, whose production demands a large amount of energy and generates a large amount of greenhouse gas emissions. In fact, the majority of natural gas available in Western Canada would be consumed by oil sands operations, if natural gas will continue to be the fuel for the operations and if the scale of oil sands operations will increase as predicted. Also, the amount of greenhouse gas emissions generated from the operations could challenge Canada's fulfillment of its Kyoto commitment of reducing Canada's total greenhouse gas emissions. In this paper, we analyzed energy use and greenhouse emissions of Canadian oil sands recovery and upgrading with the current practice (where steam and hydrogen are produced with natural gas) and with alternative practices of providing steam and hydrogen. Although we found that the current practices requires a large amount of natural gas and generates a large amount of greenhouse gases, alternatives such as using nuclear power to provide steam and hydrogen can help reduce natural gas requirements and reduce greenhouse gas emissions. In contrast, if coal is used to generate steam and hydrogen, greenhouse gas emissions could be increased further from the current practice. We realize that nuclear-based options are long-term options. However, there is also an anticipated long-term demand for hydrogen for fuel-cell vehicle applications. While fuel-cell vehicles are still in the research and development stage, the immediate demand for hydrogen by oil sands operations could help jump start low-carbon hydrogen production technologies such as nuclear-based options. Low-emissions hydrogen production operations for oil sands operations could thereby offer a test bed for low-emission hydrogen production options for fuel-cell vehicle applications.
Mobility Chains Analysis of Technologies for Passenger Cars and Light-Duty Vehicles Fueled with Biofuels: Application of the GREET Model to the Role of Biomass in America's Energy Future (RBAEF) Project
M. Wu, Y. Wu, M. Wang
http://greet.es.anl.gov/publication-ifjibaj3
This report documents the production of multiple cellulosic biofuels from switchgrass via biochemical and thermochemical conversions. Bioethanol was produced through consolidated bioprocessing. Bio-Fischer-Tropsch diesel, bio-Fischer-Tropsch naphtha, bio-dimethyl-ether, and co-product bio-electricity were produced through thermochemical gasification followed by syngas synthesis and GTCC or steam turbine. Pathways analysis was based on process simulation by Dartmouth College and Princeton University. They evaluated energy and GHG benefits of cellulosic biofuels in the year 2025. Results of this study show various production options using switchgrass-based biofuel, their fossil energy use, and life cycle GHG emission reductions relative to conventional gasoline. GREET's herbaceous ethanol pathway was updated through this effort.
GM Study: Well-to-Wheels Analysis of Advanced Fuel/Vehicle Systems - A North American Study of Energy Use, Greenhouse Gas Emissions, and Criteria Pollutant Emissions
N. Brinkman, M. Wang, T. Weber, T. Darlington
http://greet.es.anl.gov/publication-4mz3q5dw
This study updates and supplements a previous (2001) North American study, conducted by GM and others (General Motors [GM] et al. 2001), of energy consumption and greenhouse gas (GHG) emissions associated with advanced vehicle/fuel systems (GM Phase 1 North American study). The primary purpose of this Phase 2 study is to address criteria pollutant emissions, including volatile organic compounds (VOCs), carbon monoxide (CO), nitrogen oxides (NOx), particulate matter with a diameter smaller than 10 microns (PM10), and sulfur oxide emissions (SOx). We also updated the vehicle modeling for energy consumption with the latest powertrain maps and added some additional propulsion systems, such as hydrogen internal combustion engines (ICEs). As in the previous study, the vehicle modeled was a 2010-model-year, full-sized GM pickup truck. The truck was selected because it is a high seller among light-duty vehicles (cars and trucks) in the U.S. market, and light-duty trucks account for a large proportion of the fuel used in the U.S. vehicle fleet. In our study, we attempted to estimate the energy use and emissions for the 2010-model-year truck fleet over its lifetime. To simplify this effort, we modeled the year 2016 - when the lifetime mileage midpoint for the truck will be reached.
The Debate on Energy and Greenhouse Gas Emissions Impacts of Fuel Ethanol
http://greet.es.anl.gov/publication-nesiqrgf
Updated Energy and Greenhouse Gas Emissions Results of Fuel Ethanol
http://greet.es.anl.gov/publication-fn174xp1
Updated Energy and Greenhouse Gas Emission Results of Fuel Ethanol
The 15th International Symposium on Alcohol Fuels
http://greet.es.anl.gov/publication-y015em1i
This paper summarizes key issues affecting WTW energy and emission results of corn and cellulosic ethanol. It is the first paper to discuss historical trends of key factors such as corn farming and ethanol production. It is also the first paper to present the energy balance of corn ethanol.
User Manual for Stochastic Simulations
K. Subramanyan, U. Diwekar
http://greet.es.anl.gov/publication-ytsz6yov
This report documents the development of the stochastic simulation features in GREET 1.7. It also presents steps in the stochastic simulation features in GREET.
Vehicle-Cycle Energy and Emission Effects of Conventional and Advanced Vehicles (abstract)
P. Moon, A. Burnham, M. Wang
SAE 2006 World Congress, Paper No. 2006-01-0375 (2006)
http://greet.es.anl.gov/publication-hkjun004
A vehicle-cycle module of the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model has been developed at Argonne National Laboratory. The fuel-cycle GREET model has been published extensively and contains data on fuel-cycles and vehicle operation. The vehicle-cycle module evaluates the energy and emission effects of vehicle material recovery and production, vehicle component fabrication, vehicle assembly, and vehicle disposal/recycling. The addition of the vehicle-cycle module to the GREET model provides a comprehensive lifecycle-based approach to compare energy use and emissions of conventional vehicle technologies and advanced vehicle technologies such as hybrid electric vehicles and fuel cell vehicles. Using the newly developed vehicle-cycle module, this paper evaluates on a vehicle-cycle basis the energy use, greenhouse gas emissions, and selected air pollutant emissions of a mid-size passenger car with the following powertrain systems - internal combustion engine, internal combustion engine with hybrid configuration, and fuel cell with hybrid configuration. We found that the production of materials accounts for a majority of the vehicle-cycle energy use and emissions of all the vehicles examined. The energy use and greenhouse gas emissions increase for the advanced powertrain vehicles compared to the internal combustion engine vehicles, due to the use of energy-intensive materials in the fuel cell system of the fuel cell vehicle and the increased use of aluminum in both the hybrid electric vehicle and the fuel cell vehicle. In addition, the use of materials such as aluminum and carbon fiber composites increases the energy use and greenhouse gas emissions of lightweight vehicles. Furthermore, in order to put vehicle-cycle results into a broad perspective, the fuel-cycle GREET model is used in conjunction with the vehicle-cycle module to estimate total energy-cycle results. Materials used to reduce the weight of a vehicle help improve fuel economy, and reduce the energy use and GHG emissions of the fuel-cycle and vehicle operation stages; however, production of lightweight materials is energy-intensive compared to production of conventional materials. However, when examining energy use and emissions on the total energy-cycle basis, our simulations show that in terms of reducing total energy use and emissions, there can be a significant net benefit from substituting lightweight materials.
Well-to-Wheels Results of Energy Use, Greenhouse Gas Emissions, and Criteria Air Pollutant Emissions of Selected Vehicle/Fuel Systems (abstract)
Y. Wu, M. Wang, P. Sharer, A. Rousseau
SAE 2006 Transactions (Journal of Engines), Paper No. 2006-01-0377 (2007)
http://greet.es.anl.gov/publication-bkdduogo
A fuel-cycle model-called the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model-has been developed at Argonne National Laboratory to evaluate well-to-wheels (WTW) energy and emission impacts of motor vehicle technologies fueled with various transportation fuels. The new GREET version has up-todate information regarding energy use and emissions for fuel production activities and vehicle operations. In this study, a complete WTW evaluation targeting energy use, greenhouse gases (CO2, CH4, and N2O), and typical criteria air pollutants (VOC, NOX, and PM10) includes the following fuel options-gasoline, diesel, and hydrogen; and the following vehicle technologies-spark-ignition engines with or without hybrid configurations, compression-ignition engines with hybrid configurations, and hydrogen fuel cells with hybrid configurations. Because the parametric assumptions in the GREET model involve uncertainties, we conducted stochastic simulations with GREET by establishing probability distribution functions for key input parameters (e.g., energy efficiencies, emission factors) regarding well-to-pump (WTP) activities and vehicle operations based on the detailed up-to-date data. We applied the Hammersley Sequence Sampling (HSS) technique for stochastic simulations in GREET to take into account the probability distributions of key input parameters, and produced the results in the form of a statistical distribution for a given energy or emission item. The WTW analysis shows that advanced vehicle/fuel systems achieve reductions in energy use, greenhouse gas emissions, and criteria pollutant emissions compared to baseline gasoline vehicles through 1) improved vehicle fuel economy, 2) reduced tailpipe/evaporative vehicle emissions, and/or 3) differences in fuel production pathways.
Well-to-Wheels Analysis of Energy Use and Greenhouse Gas Emissions of Hydrogen Produced with Nuclear Energy (abstract)
Y. Wu, M. Wang, A. Vyas, D. Wade, T. Taiwo
Nuclear Technologies 155: 92-207
http://greet.es.anl.gov/publication-rlrzhswg
A fuel-cycle model—called the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model—has been developed to evaluate well-to-wheels (WTW) energy and emission impacts of motor vehicle technologies fueled with various transportation fuels. The GREET model contains various hydrogen (H2) production pathways for fuel-cell vehicles (FCVs) applications. In this study, the GREET model was expanded to include four nuclear H2 production pathways: (1) H2 production at refueling stations via electrolysis using light water reactor (LWR)-generated electricity; (2) H2 production in central plants via thermo-chemical water cracking using heat from high temperature gas-cooled reactor (HTGR); (3) H2 production in central plants via high-temperature electrolysis using HTGR-generated electricity and steam; and (4) H2 production at refueling stations via electrolysis using HTGR-generated electricity. The WTW analysis of these four options include these stages: uranium ore mining and milling; uranium yellowcake transportation; uranium conversion; uranium enrichment; uranium fuel fabrication; uranium fuel transportation; electricity or H2 production in nuclear power plants; H2 transportation; H2 compression; and H2 FCVs operation. Our well-to-pump (WTP) results show that significant reductions in fossil energy use and greenhouse gas (GHG) emissions are achieved by nuclear-based H2 compared to natural gas-based H2 production via steam methane reforming for a unit of H2 delivered at refueling stations. When H2 is applied to FCVs, the WTW results also show large benefit in reducing fossil energy use and GHG emissions.
Energy and Emission Benefits of Alternative Transportation Liquid Fuels Derived from Switchgrass: A Fuel Life Cycle Assessment (abstract)
Biotechnology Progress, Volume 22: 1012-1024 (2006)
http://greet.es.anl.gov/publication-vo79javl
We conducted a mobility chains - or well-to-wheels (WTW) - analysis to assess the energy and emission benefits of cellulosic biomass for the U.S. transportation sector in the years 2015 to 2030. We estimated the life-cycle energy consumption and emissions associated with biofuel production and use in light-duty vehicle (LDV) technologies by using the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model. Analysis of biofuel production was based on ASPEN Plus model simulation of an advanced fermentation process to produce fuel ethanol/protein, a thermochemical process to produce Fischer-Tropsch diesel (FTD) and dimethyl ether (DME), and a combined heat and power plant to co-produce steam and electricity. Our study revealed that cellulosic biofuels as E85 (mixture of 85% ethanol and 15% gasoline by volume), FTD, and DME offer substantial savings in petroleum (66-93%) and fossil energy (65-88%) consumption on a per-mile basis. Decreased fossil fuel use translates to 82-87% reductions in greenhouse gas emissions across all unblended cellulosic biofuels. In urban areas, our study shows net reductions for almost all criteria pollutants with the exception of carbon monoxide (unchanged), for each of the biofuel production option examined. Conventional and hybrid electric vehicles, when fueled with E85, could reduce total sulfur oxide (SOx) emissions to 39-43% of those generated by vehicles fueled with gasoline. By using bio-FTD and bio-DME in place of diesel, SOx emissions are reduced to 46-58% of those generated by diesel-fueled vehicles. Six different fuel production options were compared. This study strongly suggests that integrated heat and power co-generation by means of gas turbine combined cycle is a crucial factor in the energy savings and emission reductions.
Ethanol: The Complete Energy Life-Cycle Picture
http://greet.es.anl.gov/publication-ws3spx3q
Development and Applications of GREET 2.7 - The Transportation Vehicle-Cycle Model
A. Burnham, M. Wang, Y. Wu
http://greet.es.anl.gov/publication-lkldbrwj
This report details the development and application of the GREET 2.7 model. The vehicle-cycle module in GREET evaluates the energy and emission effects associated with vehicle material recovery and production, vehicle component fabrication, vehicle assembly, and vehicle disposal/recycling. With the addition of the vehicle-cycle module, the GREET model now provides a comprehensive, lifecycle-based approach to compare the energy use and emissions of conventional and advanced vehicle technologies (e.g., hybrid electric vehicles and fuel cell vehicles). The current model includes six vehicle combinations consisting of a conventional material or lightweight material version of a mid-size passenger car with either an internal combustion engine, an internal combustion engine with hybrid configuration, or a fuel cell with hybrid configuration. The model calculates the energy use and emissions that are required for vehicle component production; battery production; fluid production and use; and vehicle assembly, disposal, and recycling. This report also presents vehicle-cycle modeling results. In order to put these results in a broad perspective, the fuel-cycle model (GREET 1.7) was used in conjunction with the vehicle-cycle model (GREET 2.7) to estimate total energy-cycle results.
Fuel-Cycle Assessment of Selected Bioethanol Production Pathways in the United States
M. Wu, M. Wang, H. Huo
http://greet.es.anl.gov/publication-2lli584z
This report documents development of pathways of producing ethanol from corn stover and forest residues in GREET. Corn stover-based ethanol is produced via biochemical conversion process based on NREL's bioconversion process simulation. Forest wood residue is a feedstock to produce multiple alcohols, ethanol, methanol, butanol, pantenol, etc., via a mixed alcohol process developed by NREL. This work is part of a DOE OBP funded 30x30 study. We re-examined fertilizer use (nitrogen, phosphorus, and potassium) and irrigation needs in the thirteen major corn-growing states, based on current USDA data. Net nitrogen requirement and N2O emissions as a result of corn stover harvest for cellulosic ethanol production was analyzed. As part of this effort, we conducted a life cycle assessment of energy use in farming machinery for the equipment used to farm corn. The assessment accounts for steel and rubber production, refining, parts production and assembly of the equipment. A historical comparison of farming machinery-embodied energy was presented. Through this effort, GREET was expanded to include the corn stover to ethanol pathway and the forest wood residue to ethanol pathway. In addition, a farming machinery embodied energy database was included in the ethanol pathway in GREET.
Projection of Chinese Motor Vehicle Growth, Oil Demand, and CO2 Emissions through 2050
M. Wang, H. Huo, L. Johnson, D. He
http://greet.es.anl.gov/publication-rwdz78ca
In this study, we developed a methodology to project trends in the growth of the vehicle population, oil demand, and CO2 emissions associated with on-road transportation in China. By using this methodology, we projected - separately - the number of highway vehicles, motorcycles, and rural vehicles in China through 2050. We used three scenarios of highway vehicle growth (high-, mid-, and low-growth) to reflect patterns of motor vehicle growth that have occurred in different parts of the world (i.e., Europe and Asia).
Operating Manual for GREET: Version 1.7
M. Wang, Y. Wu, A. Elgowainy
November 1, 2005 revised on: February 1, 2007
http://greet.es.anl.gov/publication-ycrv02rp
This is the operating manual of GREET 1.7. It lists the more than 100 fuel production pathways and 70 vehicle/fuel systems that are simulated and describes the content each of the 27 individual working sheets in this version. It also explains to users the new GREET simulation features and simulations steps.
Life-Cycle Energy and Greenhouse Gas Emission Impacts of Different Corn Ethanol Plant Types
M. Wang, M. Wu, H. Huo
Environmental Research Letters, Vol. 2 (2007), 024001
http://greet.es.anl.gov/publication-zgd4vecz
This paper documents key assumptions of corn ethanol plant energy use by process fuel types. We examine nine corn ethanol plant types categorized according to the type of process fuels employed, use of combined heat and power, and production of wet distillers grains and solubles. Process fuels in corn ethanol plants include natural gas, coal, wet DGS, and wood chips. We found that these ethanol plant types can have distinctly different energy and greenhouse gas emission effects on a full fuel-cycle basis. In particular, greenhouse gas emission impacts can vary significantly - from a 3% increase if coal is the process fuel, to a 52% reduction if wood chips are used. As a result, the GREET model was expanded to include these process fuels for corn ethanol plants.
Potential Energy and Greenhouse Gas Emission Effects of Hydrogen Production from Coke Oven Gas in U.S. Steel Mills (abstract)
F. Joseck, M. Wang, Y. Wu
International Journal of Hydrogen, 33, 1445 - 1454
http://greet.es.anl.gov/publication-koec42fk
For this study, we examined the energy and emission effects of hydrogen production from coke oven gas (COG) on a well-to-wheels basis and compared these effects with those of other hydrogen production options, as well as with those of conventional gasoline and diesel options. We then estimated the magnitude of hydrogen production from COG in the United States and the number of hydrogen fuel cell vehicles (FCVs) that could potentially be fueled with the hydrogen produced from COG. Our analysis shows that this production pathway can achieve energy and greenhouse gas emission reduction benefits. This pathway is especially worth considering because first, the sources of COG are concentrated in the upper Midwest and in the Northeast United States, which would facilitate relatively cost-effective collection, transportation, and distribution of the produced hydrogen to refueling stations in these regions. Second, the amount of hydrogen that could be produced may fuel about 1.7 million cars, thus providing a vital near-term hydrogen production option for FCV applications.
Life-Cycle Assessment of Corn-Based Butanol as a Potential Transportation Fuel
M. Wu, M. Wang, J. Liu, H. Huo
http://greet.es.anl.gov/publication-4i3trvf0
This report documents the development and simulation of corn-based butanol through advanced ABE (acetone, butanol, and ethanol) fermentation. The production pathway produces bio-butanol as a fuel blend, large quantity of co-product bio-acetone, and small amount of bio-ethanol. First, a process simulation for corn-based butanol production was conducted using ASPEN Plus. The simulation was partly based on USDA's corn ethanol dry-mill process model for the process steps prior to fermentation. The upstream production process steps were integrated into ABE fermentation and downstream processing for products separation, which was simulated using the most recent literature values. Results from the ASPEN model served as inputs to estimate life cycle energy use and associated emissions. The report also presents a WTW bio-butanol used in LDV and a cradle-to-gate analysis of bio-acetone. Results from this effort were incorporated into GREET for the corn butanol pathway and corn ethanol pathway.
Stochastic Tool Loading Instructions
A. Elgowainy
http://greet.es.anl.gov/publication-he5am4um
Estimation of Energy Efficiencies of U.S. Petroleum Refineries
http://greet.es.anl.gov/publication-hl9mw9i7
This document details petroleum refining efficiencies from LP simulations of petroleum refineries and EIA survey data of petroleum refineries up to 2006.
Life-Cycle Assessment of Energy and Greenhouse Gas Effects of Soybean-Derived Biodiesel and Renewable Fuels
H. Huo, M. Wang, C. Bloyd, V. Putsche
http://greet.es.anl.gov/publication-e5b5zeb7
This report documents development of soybean-based renewable diesel and renewable gasoline pathways and update of soybean-based biodiesel pathways in GREET 1.8. We assessed the life-cycle energy and greenhouse gas (GHG) emission impacts of three soybean-derived fuels by expanding, updating, and using the GREET model including biodiesel produced from soy oil transesterification; renewable diesel produced from hydrogenation of soy oil by using two processes (renewable diesel I and II); and renewable gasoline produced from catalytic cracking of soy oil. We used four allocation approaches to address the co-products: a displacement approach; two allocation methods, one based on energy value and one based on market value; and a hybrid approach that integrates both the displacement and allocation methods. Each of the four allocation approaches generates different results.
Argonne and DOE respond to the February 7 article in Sciencexpress, Use of U.S. Croplands for Biofuels Increases Greenhouse Gases through Emissions from Land Use Change
M. Wang, Z. Haq
http://greet.es.anl.gov/publication-z3ko5q7x
Life-Cycle Energy Use and Greenhouse Gas Emission Implications of Brazilian Sugarcane Ethanol Simulated with the GREET Model (abstract)
M. Wang, M. Wu, H. Huo, J. Liu
International Sugar Journal 2008, Vol. 110, No. 1317
http://greet.es.anl.gov/publication-hjk5cxlv
By using data available in the open literature, we expanded the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model developed by Argonne National Laboratory to include Brazilian-grown sugarcane ethanol. With the expanded GREET model, we examined the well-to-wheels (WTW) energy use and greenhouse gas (GHG) emissions of sugarcane-derived ethanol produced in Brazil and used to fuel light-duty vehicles in the United States. Results for sugarcane ethanol were compared with those for petroleum gasoline. The sugarcane-to-ethanol pathway evaluated in the GREET model comprises fertilizer production, sugarcane farming, sugarcane transportation, and sugarcane ethanol production in Brazil; ethanol transportation to U.S. ports and then to U.S. refueling stations; and ethanol use in vehicles. Our analysis shows that sugarcane ethanol can reduce GHG emissions by 78% and fossil energy use by 97%, relative to petroleum gasoline. The large reductions can be attributed to use of bagasse in sugarcane mills, among other factors. To address the uncertainties involved in key input parameters, we developed and examined several sensitivity cases to test the effect of key parameters on WTW results for sugarcane ethanol. Of the total GHG emissions associated with sugarcane ethanol, the five major contributors are open-field burning of sugarcane tops and leaves, N2O emissions from sugarcane fields, fertilizer production, sugarcane mill operation, and sugarcane farming. Brazil is going to phase out open-field burning in the future. This action will certainly help further reduce GHG emissions of sugarcane farming, together with reductions in emissions of criteria pollutants such as Nox and particulate matter with diameters smaller than 10 microns. The eventual elimination of open-field burning in sugarcane plantations will result in additional GHG emission reductions by sugarcane ethanol of up to 9 percentage points.
Update of Distillers Grains Displacement Ratios for Corn Ethanol Life-Cycle Analysis
S. Arora, M. Wu, M. Wang
http://greet.es.anl.gov/publication-3bi0z09m
This report details the effort in updating the displacement ratios of dry milling corn-ethanol co-products used in the animal feed industry for use in the GREET model. Displacement ratios of corn-ethanol co-products including DGS, CGM, and CGF were last updated in 1998 at a workshop at Argonne National Laboratory on the basis of input from a group of experts on animal feeds. Production of corn-based ethanol (either by wet milling or by dry milling) yields the following co-products: distillers grains with solubles (DGS), corn gluten meal (CGM), corn gluten feed (CGF), and corn oil. Of these co-products, all except corn oil can replace conventional animal feeds, such as corn, soybean meal, and urea.
Assessment of Potential Life-Cycle Energy and Greenhouse Gas Emission Effects from Using Corn-Based Butanol as a Transportation Fuel (abstract)
http://greet.es.anl.gov/publication-o5j5z7yi
Since advances in the ABE (acetone-butanol-ethanol) fermentation process in recent years have led to significant increases in its productivity and yields, the production of butanol and its use in motor vehicles have become an option worth evaluating. This study estimates the potential lifecycle energy and emission effects associated with using bio-butanol as a transportation fuel. It employs a well-to-wheels (WTW) analysis tool: the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The estimates of life-cycle energy use and greenhouse gas (GHG) emissions are based on an Aspen PlusVVR simulation for a corn-to-butanol production process, which describes grain processing, fermentation, and product separation. Bio-butanol-related WTW activities include corn farming, corn transportation, butanol production, butanol transportation, and vehicle operation. In this study, we also analyzed the bio-acetone that is coproduced with bio-butanol as an alternative to petroleum-based acetone. We then compared the results for bio-butanol with those of conventional gasoline. Our study shows that driving vehicles fueled with corn-based butanol produced by the current ABE fermentation process could result in substantial fossil energy savings (39%-56%) and avoid large percentage of the GHG emission burden, yielding a 32%-48% reduction relative to using conventional gasoline. On energy basis, a bushel of corn produces less liquid fuel from the ABE process than that from the corn ethanol dry mill process. The coproduction of a significant portion of acetone from the current ABE fermentation presents a challenge. A market analysis of acetone, as well as research and development on robust alternative technologies and processes that minimize acetone while increase the butanol yield, should be conducted.
Full Fuel-Cycle Comparison of Forklift Propulsion Systems
L. Gaines, A. Elgowainy, M. Wang
http://greet.es.anl.gov/publication-oh77n5k5
This report examines forklift propulsion systems and addresses the potential energy and environmental implications of substituting fuel-cell propulsion for existing technologies based on batteries and fossil fuels. Industry data and the Argonne GREET model are used to estimate full fuelcycle emissions and use of primary energy sources, back to the primary feedstocks for fuel production. Also considered are other environmental concerns at work locations. The benefits derived from using fuel-cell propulsion are determined by the sources of electricity and hydrogen. In particular, fuel-cell forklifts using hydrogen made from the reforming of natural gas had lower impacts than those using hydrogen from electrolysis.
Fuel Cycle Comparison of Distributed Power Generation Technologies
A. Elgowainy, M. Wang
http://greet.es.anl.gov/publication-l4gwiacu
The fuel-cycle energy use and greenhouse gas (GHG) emissions associated with the application of fuel cells to distributed power generation were evaluated and compared with the combustion technologies of microturbines and internal combustion engines, as well as the various technologies associated with grid-electricity generation in the United States and California. The results were primarily impacted by the net electrical efficiency of the power generation technologies and the type of employed fuels. The energy use and GHG emissions associated with the electric power generation represented the majority of the total energy use of the fuel cycle and emissions for all generation pathways. Fuel cell technologies exhibited lower GHG emissions than those associated with the U.S. grid electricity and other combustion technologies. The higher-efficiency fuel cells, such as the solid oxide fuel cell (SOFC) and molten carbonate fuel cell (MCFC), exhibited lower energy requirements than those for combustion generators. The dependence of all natural-gas-based technologies on petroleum oil was lower than that of internal combustion engines using petroleum fuels. Most fuel cell technologies approaching or exceeding the DOE target efficiency of 40% offered significant reduction in energy use and GHG emissions.
Well-to-Wheels Energy Use and Greenhouse Gas Emissions Analysis of Plug-in Hybrid Electric Vehicles
A. Elgowainy, A. Burnham, M. Wang, J. Molburg, A. Rousseau
http://greet.es.anl.gov/publication-372dv49w
This report examines the well-to-wheels energy use and greenhouse gas emissions of plug-in hybrid electric vehicles. The analysis incorporated fuel economy results from the Powertrain System Analysis Toolkit for PHEV and marginal electricity generation mixes from the Oak Ridge Competitive Electricity Dispatch Model. The WTW results were separately calculated for the blended charge-depleting and charge-sustaining modes of PHEV operation and then combined by using a weighting factor that represented the CD vehicle-miles-traveled share. GREET 1.8c.0 incorporates these changes for the simulation of PHEVs.
Water Consumption in the Production of Ethanol and Petroleum Gasoline (abstract)
M. Wu, M. Mintz, M. Wang, S. Arora
Environmental Management, Volume 44: 981-997 (2009)
http://greet.es.anl.gov/publication-ebqyv6y5
We assessed current water consumption during liquid fuel production, evaluating major steps of fuel lifecycle for five fuel pathways: bioethanol from corn, bioethanol from cellulosic feedstocks, gasoline from U.S. conventional crude obtained from onshore wells, gasoline from Saudi Arabian crude, and gasoline from Canadian oil sands. Our analysis revealed that the amount of irrigation water used to grow biofuel feedstocks varies significantly from one region to another and that water consumption for biofuel production varies with processing technology. In oil exploration and production, water consumption depends on the source and location of crude, the recovery technology, and the amount of produced water re-injected for oil recovery. Our results also indicate that crop irrigation is the most important factor determining water consumption in the production of corn ethanol. Nearly 70% of U.S. corn used for ethanol is produced in regions where 10-17 liters of water are consumed to produce one liter of ethanol. Ethanol production plants are less water intensive and there is a downward trend in water consumption. Water requirements for switchgrass ethanol production vary from 1.9 to 9.8 liters for each liter of ethanol produced. We found that water is consumed at a rate of 2.8-6.6 liters for each liter of gasoline produced for more than 90% of crude oil obtained from conventional onshore sources in the U.S. and more than half of crude oil imported from Saudi Arabia. For more than 55% of crude oil from Canadian oil sands, about 5.2 liters of water are consumed for each liter of gasoline produced. Our analysis highlighted the vital importance of water management during the feedstock production and conversion stage of the fuel lifecycle.
Modeling Energy and Greenhouse Gas Emissions of CNG and LNG Produced from Landfill Gas, AF+V National Conference
M. Mintz
http://greet.es.anl.gov/publication-mtqri71u
Well-to-Wheels Analysis of Biofuels and Plug-In Hybrids
http://greet.es.anl.gov/publication-psj0nabb1
Simulation of the Process for Producing Butanol from Corn Fermentation (abstract)
J. Liu, M. Wu, M. Wang
Industrial & Engineering Chemistry Research Journal 2009, Vol. 48, 5551-5557
http://greet.es.anl.gov/publication-pn8d524r
This study focuses on the simulation of a complete process for producing butanol via acetone, butanol, and ethanol corn fermentation. The simulation, which begins with grain processing and proceeds through product purification, represents the first attempt to simulate such a complete process. Energy use for the production process is highlighted and compared to that for the conventional corn ethanol process. The simulation results are utilized in a lifecycle assessment for butanol as a potential transportation fuel. The lifecycle assessment study is conducted using the transportation full lifecycle assessment model, Greenhouse Gases, Regulated Emissions and Energy Use in Transportation (GREET), that has been developed by Argonne National Laboratory. A variety of key parameters are examined, such as the state of the art of the unit operations included in the process and their key process parameters, as well as their effects on the total energy consumption and greenhouse gas emissions in the lifecycle of butanol.
Water Is Key to Sustainability of Energy Production
M. Wu, M. Mintz, M. Wang, S. Arora, and J. Peng
http://greet.es.anl.gov/publication-61nj711t
What's Your Carbon Footprint?
A. Burnham, M. Vilim, A. Elgowainy
http://greet.es.anl.gov/publication-nvedvh25
Well-to-Wheels Analysis of Landfill Gas-Based Pathways and Their Addition to the GREET Model
M. Mintz, J. Han, M. Wang, C. Saricks
http://greet.es.anl.gov/publication-xkdaqgyk0
This report discusses the size and scope of biomethane resources from landfills and the pathways by which those resources can be turned into and utilized as vehicle fuel. It includes characterizations of the LFG stream and the processes used to convert low-Btu LFG into high-Btu renewable natural gas (RNG); documents the conversion efficiencies and losses of those processes, the choice of processes modeled in GREET, and other assumptions used to construct GREET pathways; and presents GREET results by pathway stage. GREET estimates of well-to-pump (WTP), pump-to-wheel (PTW), and WTW energy, fossil fuel, and GHG emissions for each LFG-based pathway are then summarized and compared with similar estimates for fossil natural gas and petroleum pathways.
Well-to-Wheels Analysis of Energy Use and Greenhouse Gas Emissions of Plug-In Hybrid Electric Vehicles
A. Elgowainy, J. Han, L. Poch, M. Wang, A. Vyas, M. Mahalik, A. Rousseau
http://greet.es.anl.gov/publication-xkdaqgyk
For this WTW analysis, Argonne National Laboratory researchers used the GREET model to compare the WTW energy use and GHG emissions associated with various transportation technologies to those associated with PHEVs. They estimated the fuel economy and electricity use of PHEVs and alternative fuel/vehicle systems by using Argonne's Powertrain System Analysis Toolkit (PSAT) model. They examined two PHEV designs: the power-split configuration and the series configuration. They calculated the equivalent "on-road" (real-world) fuel economy on the basis of U.S. Environmental Protection Agency miles per gallon (mpg)-based formulas. They employed detailed dispatch models to simulate the electric power systems in four major regions of the United States. Argonne also evaluated the U.S. average generation mix and renewable generation of electricity for PHEV and BEV recharging scenarios to show the effects of these generation mixes on the WTW results.
Land Use Changes and Consequent CO2 Emissions due to US Corn Ethanol Production: A Comprehensive Analysis
W. Tyner, F. Taheripour, Q. Zhuang, D. Birur, U. Baldos
http://greet.es.anl.gov/publication-8vdox40k
The basic objective of this research was to estimate land use changes associated with US corn ethanol production up to the 15 billion gallon Renewable Fuel Standard level implied by the Energy Independence and Security Act of 2007. We also used the estimated land use changes to calculate greenhouse gas emissions associated with the corn ethanol production. The results of this research were adapted to the GREET model.
Life-Cycle Analysis Results of Geothermal Systems in Comparison to Other Power Systems
J. Sullivan, C. Clark, J. Han, M. Wang
http://greet.es.anl.gov/publication-geothermal_and_other_power
A life-cycle energy and greenhouse gas emissions analysis has been conducted with Argonne National Laboratory's expanded Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model for geothermal power-generating technologies, including enhanced geothermal, hydrothermal flash, and hydrothermal binary technologies. As a basis of comparison, a similar analysis has been conducted for other power-generating systems, including coal, natural gas combined cycle, nuclear, hydroelectric, wind, photovoltaic, and biomass by expanding the GREET model to include power plant construction for these latter systems with literature data. In this way, the GREET model has been expanded to include plant construction, as well as the usual fuel production and consumption stages of power plant life cycles. For the plant construction phase, on a per-megawatt (MW) output basis, conventional power plants in general are found to require less steel and concrete than renewable power systems. With the exception of the concrete requirements for gravity dam hydroelectric, enhanced geothermal and hydrothermal binary used more of these materials per MW than other renewable power-generation systems. Energy and greenhouse gas (GHG) ratios for the infrastructure and other lifecycle stages have also been developed in this study per kilowatt-hour (kWh) of electricity output by taking into account both plant capacity and plant lifetime. Generally, energy burdens per energy output associated with plant infrastructure are higher for renewable systems than conventional ones. GHG emissions per kWh of electricity output for plant construction follow a similar trend. Although some of the renewable systems have GHG emissions during plant operation, they are much smaller than those emitted by fossil fuel thermoelectric systems. Binary geothermal systems have virtually insignificant GHG emissions compared to fossil systems. Taking into account plant construction and operation, the GREET model shows that fossil thermal plants have fossil energy use and GHG emissions per kWh of electricity output about one order of magnitude higher than renewable power systems, including geothermal power.
Energy-Consumption and Carbon-Emission Analysis of Vehicle and Component Manufacturing
J. Sullivan, A. Burnham, M. Wang
http://greet.es.anl.gov/publication-vehicle_and_components_manufacturing
A model is presented for calculating the environmental burdens of the part manufacturing and vehicle assembly (VMA) stage of the vehicle life cycle. The approach is bottom-up, with a special focus on energy consumption and CO2 emissions. The model is applied to both conventional and advanced vehicles, the latter of which include aluminum-intensive, hybrid electric, plug-in hybrid electric and all-electric vehicles.
GREET Brochure
http://greet.es.anl.gov/publication-nveasddvh25
A Review of Battery Life-Cycle Analysis: State of Knowledge and Critical Needs
J. Sullivan, L. Gaines
http://greet.es.anl.gov/publication-batteries_lca
A literature review and evaluation has been conducted on cradle-to-gate life-cycle inventory studies of lead-acid, nickel-cadmium, nickel-metal hydride, sodium-sulfur, and lithium-ion battery technologies. Data were sought that represent the production of battery constituent materials and battery manufacture and assembly. Life-cycle production data for many battery materials are available and usable, though some need updating. For the remaining battery materials, life-cycle data either are nonexistent or, in some cases, in need of updating. Although battery manufacturing processes have occasionally been well described, detailed quantitative information on energy and material flows is missing. For all but the lithium-ion batteries, enough constituent material production energy data are available to approximate material production energies for the batteries, though improved input data for some materials are needed. Due to the potential benefit of battery recycling and a scarcity of associated data, there is a critical need for life-cycle data on battery material recycling. Either on a per kilogram or per watt-hour capacity basis, lead-acid batteries have the lowest production energy, carbon dioxide emissions, and criteria pollutant emissions. Some process-related emissions are also reviewed in this report.
Estimated displaced products and ratios of distillers co-products from corn ethanol plants and the implications of lifecycle analysis
Salil Arora, May Wu, Michael Wang
https://www.tandfonline.com/doi/abs/10.4155/bfs.10.60?journalCode=tbfu20
http://greet.es.anl.gov/publication-corn-ethanol-displaced-products
Displacement of conventional animal feed components - corn, soybean meal and urea - by distillers coproducts has been revisited. We developed the distillers co-products displacement ratios at different levels: the feedlot level, the US market level and the composite US and export market level, in order to provide a relevant estimate for ethanol plant operators, stakeholders and decision makers. As expected, corn is still the single largest component in the conventional beef cattle diet to be displaced by distillers' co-products, followed by soybean meal. On average, 1 kg of wet distillers grains could displace 1.313 kg of corn and urea together, when it is used as a substitute in the diet of beef cattle; for distillers dried grain with solubles, 1.271 kg of corn and urea can be displaced per kg of distillers dried grain with solubles fed to beef cattle. Uncertainties about the consistency of reported data, export market and emerging new co-products are discussed. In addition, the use of distillers co-products as an animal feed may have an indirect impact on the lifecycle assessment of corn ethanol.
User Guide for the GREET Fleet Footprint Calculator 1.1
A. Burnham
June 1, 2009 revised on: December 3, 2010
http://greet.es.anl.gov/publication-4elg4zj7
This user guide documents the GREET Fleet Footprint Calculator, which can be used to measure the petroleum displacement and greenhouse gas (GHG) emissions of medium- and heavy-duty vehicles and off-road equipment.
Assessment of Fuel-Cycle Energy Use and Greenhouse Gas Emissions for Fischer-Tropsch Diesel from Coal and Cellulosic Biomass
Xiaomin Xie, Michael Wang, and Jeongwoo Han
http://pubs.acs.org/doi/abs/10.1021/es1017703
http://greet.es.anl.gov/publication-ftd-coal-biomass
This study expands and uses the GREET (Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation) model to assess the effects of carbon capture and storage (CCS) technology and cellulosic biomass and coal cofeeding in Fischer−Tropsch (FT) plants on energy use and greenhouse gas (GHG) emissions of FT diesel (FTD). To demonstrate the influence of the coproduct credit methods on FTD life-cycle analysis (LCA) results, two allocation methods based on the energy value and the market revenue of different products and a hybrid method are employed. With the energy-based allocation method, fossil energy use of FTD is less than that of petroleum diesel, and GHG emissions of FTD could be close to zero or even less than zero with CCS when forest residue accounts for 55% or more of the total dry mass input to FTD plants. Without CCS, GHG emissions are reduced to a level equivalent to that from petroleum diesel plants when forest residue accounts for 61% of the total dry mass input. Moreover, we show that coproduct method selection is crucial for LCA results of FTD when a large amount of coproducts is produced.
Developing a Tool to Estimate Water Use in Electric Power Generation in the United States
M. Wu, M. Peng
December 22, 2010 revised on: July 29, 2011
http://greet.es.anl.gov/publication-watertool
A spreadsheet-based tool has been developed to characterize water use in electricity generation from nonrenewable and renewable sources for the 50 states in the United States. The tool is built upon a data inventory that analyzes water requirements by fuel source, generation technology, and cooling system. A total of 13 fuel sources and their 19 subcategories and eight electricity generation technologies are included in the inventory. It also incorporates four types of cooling systems: for each type, water withdrawal and consumption factors were determined. The data inventory and the tool cover the 50 states in the nation which enable users to generate scenarios at national level and for individual state. As such, the tool allows decision makers to perform quick estimates of water consumption in electricity generation. It enables the projection of future water use in electricity generation from various fuel sources at state and national levels. Further analysis can be conducted to examine how changes in fuel source mix and cooling system mix impact water use. Decision makers can use the tool to compare options among fuel sources and technologies from the perspective of impacts to water use (i.e., withdrawal and consumption), to evaluate the conservation of water resources associated with renewable sources, and to address environmental sustainability issues in renewable energy development
GTAP Cellulosic Biofuels Analysis of Land Use Changes
F. Taheripour, W. Tyner, M. Wang
http://greet.es.anl.gov/publication-luc_ethanol
Waste-to-Wheel Analysis of Anaerobic-Digestion-Based Renewable Natural Gas Pathways with the GREET Model
J. Han, M. Mintz, M.Q Wang
http://greet.es.anl.gov/publication-waste-to-wheel-analysis
In 2009, manure management accounted for 2,356 Gg or 107 billion standard cubic ft of methane (CH4) emissions in the United States, equivalent to 0.5% of U.S. natural gas (NG) consumption. Owing to the high global warming potential of methane, capturing and utilizing this methane source could reduce greenhouse gas (GHG) emissions. The extent of that reduction depends on several factors—most notably, how much of this manure-based methane can be captured, how much GHG is produced in the course of converting it to vehicular fuel, and how much GHG was produced by the fossil fuel it might displace. A life-cycle analysis was conducted to quantify these factors and, in so doing, assess the impact of converting methane from animal manure into renewable NG (RNG) and utilizing the gas in vehicles. Several manure-based RNG pathways were characterized in the GREET (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model, and their fuel-cycle energy use and GHG emissions were compared to petroleum-based pathways as well as to conventional fossil NG pathways. Results show that despite increased total energy use, both fossil fuel use and GHG emissions decline for most RNG pathways as compared with fossil NG and petroleum. However, GHG emissions for RNG pathways are highly dependent on the specifics of the reference case, as well as on the process energy emissions and methane conversion factors assumed for the RNG pathways. The most critical factors are the share of flared controllable CH4 and the quantity of CH4 lost during NG extraction in the reference case, the magnitude of N2O lost in the anaerobic digestion (AD) process and in AD residue, and the amount of carbon sequestered in AD residue. In many cases, data for these parameters are limited and uncertain. Therefore, more research is needed to gain a better understanding of the range and magnitude of environmental benefits from converting animal manure to RNG via AD.
Life-Cycle Analysis of Algal Lipid Fuels with the GREET Model
E.D. Frank, J. Han, I, Palou-Rivera, A. Elgowainy, M.Q. Wang
http://greet.es.anl.gov/publication-algal-lipid-fuels
Water Resource Assessment of Geothermal Resources and Water Use in Geopressured Geothermal Systems
C.E. Clark, C.B Harto, W.A. Troppe
http://greet.es.anl.gov/publication-water-use-pressurized-geothermal
Updated Sugarcane and Switchgrass Parameters in the GREET Model
J. B. Dunn, J. Eason, M Q. Wang
http://greet.es.anl.gov/publication-updated_sugarcane_switchgrass_params
The feedstock from which a biofuel derives can have a significant effect on its life-cycle energy consumption and emissions of greenhouse gases (GHG). The aim of this document is to describe our approach to developing GREET parameters for key facets of sugarcane and switchgrass feedstocks that affect their life-cycle air emissions and energy consumption from the field (including the upstream energy to manufacture agricultural inputs such as fertilizer) to the conversion facility gate in the case of switchgrass. For sugarcane ethanol, we also revise aspects of the fuel's life cycle pertaining to the conversion facility including ethanol yield and embodied energy in the sugarcane mill buildings and equipment. A summary of data sources for corn stover and forest residue are provided elsewhere (Han et al. 2011). Note that although this document discusses switchgrass in the context of ethanol production, this crop could also be a feed to a process that directly produces hydrocarbon fuels, such as fast pyrolysis.
User Manual for Algae Life-Cycle Analysis with GREET
http://greet.es.anl.gov/publication-algae-life-cycle-manual
Updated Estimation of Energy Efficiencies of U.S. Petroleum Refineries
I. Palou-Rivera, J. Han, M. Wang
July 1, 2010 revised on: November 2, 2011
http://greet.es.anl.gov/publication-petroleum
Argonne has developed petroleum refining efficiencies from LP simulations of petroleum refineries and EIA survey data of petroleum refineries up to 2006 (see Wang, 2008). This memo documents Argonne's most recent update of petroleum refining efficiencies.
Life-Cycle Greenhouse Gas Emissions of Shale Gas, Natural Gas, Coal, and Petroleum
Andrew Burnham, Jeongwoo Han, Corrie E. Clark, Michael Wang, Jennifer B. Dunn, Ignasi Palou-Rivera
http://dx.doi.org/10.1021/es201942m
http://greet.es.anl.gov/publication-GHGs-Shale-NG-Coal-Petroleum
The technologies and practices that have enabled the recent boom in shale gas production have also brought attention to the environmental impacts of its use. It has been debated whether the fugitive methane emissions during the natural gas production and transmission outweigh the lower carbon dioxide emissions during combustion when compared to coal and petroleum. Using the current state of knowledge of methane emissions from shale gas, conventional natural gas, coal, and petroleum, we estimated up-to-date life-cycle greenhouse gas emissions. In addition, we developed distribution functions for key parameters in each pathway to examine uncertainty and identify data gaps such as methane emissions from shale gas well completions and conventional natural gas liquid unloadings that need to be further addressed. Our base case results show that shale gas life-cycle emissions are 6% lower than conventional natural gas, 23% lower than gasoline, and 33% lower than coal. However, the range in values for shale and conventional gas overlap, so there is a statistical uncertainty whether shale gas emissions are indeed lower than conventional gas. Moreover, this life-cycle analysis, among other work in this area, provides insight on critical stages that the natural gas industry and government agencies can work together on to reduce the greenhouse gas footprint of natural gas. Keywords: life cycle analysis, greenhouse gas emissions, shale gas, natural gas, coal, petroleum
Well-to-Wheels Analysis of Fast Pyrolysis Pathways with GREET
J.Han, A.Elgowainy, I. Palou-Rivera, J.B. Dunn, M.Q. Wang
http://greet.es.anl.gov/publication-wtw_fast_pyrolysis
The pyrolysis of biomass can help produce liquid transportation fuels with properties similar to those of petroleum gasoline and diesel fuel. Argonne National Laboratory conducted a life-cycle (i.e., well-to-wheels [WTW]) analysis of various pyrolysis pathways by expanding and employing the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The WTW energy use and greenhouse gas (GHG) emissions from the pyrolysis pathways were compared with those from the baseline petroleum gasoline and diesel pathways. Various pyrolysis pathway scenarios with a wide variety of possible hydrogen sources, liquid fuel yields, and co-product application and treatment methods were considered. At one extreme, when hydrogen is produced from natural gas and when bio-char is used for process energy needs, the pyrolysis-based liquid fuel yield is high (32% of the dry mass of biomass input). The reductions in WTW fossil energy use and GHG emissions relative to those that occur when baseline petroleum fuels are used, however, is modest, at 50% and 51%, respectively, on a per unit of fuel energy basis. At the other extreme, when hydrogen is produced internally via reforming of pyrolysis oil and when bio-char is sequestered in soil applications, the pyrolysis-based liquid fuel yield is low (15% of the dry mass of biomass input), but the reductions in WTW fossil energy use and GHG emissions are large, at 79% and 96%, respectively, relative to those that occur when baseline petroleum fuels are used. The petroleum energy use in all scenarios was restricted to biomass collection and transportation activities, which resulted in a reduction in WTW petroleum energy use of 92-95% relative to that found when baseline petroleum fuels are used. Internal hydrogen production (i.e., via reforming of pyrolysis oil) significantly reduces fossil fuel use and GHG emissions because the hydrogen from fuel gas or pyrolysis oil (renewable sources) displaces that from fossil fuel natural gas and the amount of fossil natural gas used for hydrogen production is reduced; however, internal hydrogen production also reduces the potential petroleum energy savings (per unit of biomass input basis) because the fuel yield declines dramatically. Typically, a process that has a greater liquid fuel yield results in larger petroleum savings per unit of biomass input but a smaller reduction in life-cycle GHG emissions. Sequestration of the large amount of bio-char co-product (e.g., in soil applications) provides a significant carbon dioxide credit, while electricity generation from bio-char combustion provides a large energy credit. The WTW energy and GHG emissions benefits observed when a pyrolysis oil refinery was integrated with a pyrolysis reactor were small when compared with those that occur when pyrolysis oil is distributed to a distant refinery, since the activities associated with transporting the oil between the pyrolysis reactors and refineries have a smaller energy and emissions footprint than do other activities in the pyrolysis pathway.
Life-Cycle Analysis Results for Geothermal Systems in Comparaison to Other Power Systems Part II
J.L Sullivan, C.E. Clark, L. Yuan, J. Han, M. Wang
http://greet.es.anl.gov/publication-lca-goethermal
Life-Cycle Analysis of Shale gas and Natural Gas
C. Clark, J.Han, A. Burnham, J.B. Dunn, M.Q. Wang
http://greet.es.anl.gov/publication-shale_gas
The technologies and practices that have enabled the recent boom in shale gas production have also brought attention to the environmental impacts of its use. Using the current state of knowledge of the recovery, processing, and distribution of shale gas and conventional natural gas, we have estimated up-to-date, life-cycle greenhouse gas emissions. In addition, we have developed distribution functions for key parameters in each pathway to examine uncertainty and identify data gaps — such as methane emissions from shale gas well completions and conventional natural gas liquid unloadings — that need to be addressed further. Our base case results show that shale gas life-cycle emissions are 6% lower than those of conventional natural gas. However, the range in values for shale and conventional gas overlap, so there is a statistical uncertainty regarding whether shale gas emissions are indeed lower than conventional gas emissions. This life-cycle analysis provides insight into the critical stages in the natural gas industry where emissions occur and where opportunities exist to reduce the greenhouse gas footprint of natural gas.
Simulated impact of future biofuel production on water quality and water cycle dynamics in the Upper Mississippi river basin
M. Wu, Y. Demissie and E. Yan
http://greet.es.anl.gov/publication-biofuel-mississippi
Biomass and Bioenergy 41 (2012):44-56
Quantifying the regional water footprint of biofuel production by incorporating hydrologic modeling
M. Wu, Y.-W. Chiu and Y. Demissie
http://dx.doi.org/10.1029/2011WR011809
http://greet.es.anl.gov/publication-water-regional-biofuels
Water Resources Research 48 (10): W10518
Life cycle analysis of geothermal power generation with supercritical carbon dioxide
Edward D Frank, John L Sullivan and Michael Q Wang
http://iopscience.iop.org/1748-9326/7/3/034030
http://greet.es.anl.gov/publication-geothermal-scco2
Life cycle analysis methods were employed to model the greenhouse gas emissions and fossil energy consumption associated with geothermal power production when supercritical carbon dioxide (scCO2) is used instead of saline geofluids to recover heat from below ground. Since a significant amount of scCO2 is sequestered below ground in the process, a constant supply is required. We therefore combined the scCO2 geothermal power plant with an upstream coal power plant that captured a portion of its CO2 emissions, compressed it to scCO2, and transported the scCO2 by pipeline to the geothermal power plant. Emissions and energy consumption from all operations spanning coal mining and plant construction through power production were considered, including increases in coal use to meet steam demand for the carbon capture. The results indicated that the electricity produced by the geothermal plant more than balanced the increase in energy use resulting from carbon capture at the coal power plant. The effective heat rate (BTU coal per total kW h of electricity generated, coal plus geothermal) was comparable to that of traditional coal, but the ratio of life cycle emissions from the combined system to that of traditional coal was 15% when 90% carbon capture efficiency was assumed and when leakage from the surface was neglected. Contributions from surface leakage were estimated with a simple model for several hypothetical surface leakage rates.
Assessing Regional Hydrology and Water Quality Implications of Large-Scale Biofuel Feedstock Production in the Upper Mississippi River Basin
Y. Demissie, E. Yan, M. Wu.
http://pubs.acs.org/doi/abs/10.1021/es300769k
http://greet.es.anl.gov/publication-regional-hydrology-mississippi
Environmental Science and Technology, 46: 9174-9182
Assessing county-level water footprints of different cellulosic-biofuel feedstock pathways
Y. W. Chiu and M. Wu
http://dx.doi.org/10.1021/es3002162
http://greet.es.anl.gov/publication-water-country-biofuel
Environmental Science and Technology 46 (16): 9155-9162
Methane and nitrous oxide emissions affect the life-cycle analysis of algal biofuels
E.D. Frank, J. Han, I. Palou-Rivera, A. Elgowainy, M.Q. Wang
http://iopscience.iop.org/1748-9326/7/1/014030/
http://greet.es.anl.gov/publication-ch4-nox-algal-biofuels
Updated Greenhouse Gas and Criteria Air Pollutant Emission Factors and Their Probability Distribution Functions for Electric Generating Units
H. Cai, M. Wang, A. Elgowainy, J. Han
http://greet.es.anl.gov/publication-updated-elec-emissions
Material and Energy Flows in the Materials Production, Assembly, and End of Life Stages of the Automotive Lithium Ion Battery Life Cycle
J.B. Dunn, L. Gaines, M. Barnes, J. Sullivan and M. Wang
http://greet.es.anl.gov/publication-lib-lca
This document contains material and energy flows for lithium-ion batteries with an active cathode material of lithium manganese oxide (LiMn2O4). These data are incorporated into Argonne National Laboratory's Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model, replacing previous data for lithium-ion batteries that are based on a nickel/cobalt/manganese (Ni/Co/Mn) cathode chemistry. To identify and determine the mass of lithium-ion battery components, we modeled batteries with LiMn2O4 as the cathode material using Argonne's Battery Performance and Cost (BatPaC) model for hybrid electric vehicles, plug-in hybrid electric vehicles, and electric vehicles. As input for GREET, we developed new or updated data for the cathode material and the following materials that are included in its supply chain: soda ash, lime, petroleum-derived ethanol, lithium brine, and lithium carbonate. Also as input to GREET, we calculated new emission factors for equipment (kilns, dryers, and calciners) that were not previously included in the model and developed new material and energy flows for the battery electrolyte, binder, and binder solvent. Finally, we revised the data included in GREET for graphite (the anode active material), battery electronics, and battery assembly. For the first time, we incorporated energy and material flows for battery recycling into GREET, considering four battery recycling processes: pyrometallurgical, hydrometallurgical, intermediate physical, and direct physical. Opportunities for future research include considering alternative battery chemistries and battery packaging. As battery assembly and recycling technologies develop, staying up to date with them will be critical to understanding the energy, materials, and emissions burdens associated with batteries.
Life cycle comparison of hydrothermal liquefaction and lipid extraction pathways to renewable diesel from algae
Edward D. Frank, Amgad Elgowainy, Jeongwoo Han, Zhichao Wang
http://www.springerlink.com/content/m320v08k21v50861/fulltext.pdf
http://greet.es.anl.gov/publication-hydro-lipid-comparaison
Algae biomass is an attractive biofuel feedstock when grown with high productivity on marginal land. Hydrothermal liquefaction (HTL) produces more oil from algae than lipid extraction (LE) does because protein and carbohydrates are converted, in part, to oil. Since nitrogen in the algae biomass is incorporated into the HTL oil, and since lipid extracted algae for generating heat and electricity are not co-produced by HTL, there are questions regarding implications for emissions and energy use. We studied the HTL and LE pathways for renewable diesel (RD) production by modeling all essential operations from nutrient manufacturing through fuel use. Our objective was to identify the key relationships affecting HTL energy consumption and emissions. LE, with identical upstream growth model and consistent hydroprocessing model, served as reference. HTL used 1.8 fold less algae than did LE but required 5.2 times more ammonia when nitrogen incorporated in the HTL oil was treated as lost. HTL RD had life cycle emissions of 31,000 gCO2 equivalent (gCO2e) compared to 21,500 gCO2e for LE based RD per million BTU of RD produced. Greenhouse gas (GHG) emissions increased when yields exceeded 0.4 g HTL oil/g algae because insufficient carbon was left for biogas generation. Key variables in the analysis were the HTL oil yield, the hydrogen demand during upgrading, and the nitrogen content of the HTL oil. Future work requires better data for upgrading renewable oils to RD and requires consideration of nitrogen recycling during upgrading
Renewable Diesel from Algal Lipids: An Integrated Baseline for Cost, Emissions, and Resource Potential from a Harmonized Model
Ryan Davis , Daniel Fishman , Edward D. Frank , Mark S. Wigmosta ,Andy Aden , Andre M. Coleman , Philip T. Pienkos , Richard J. Skaggs, Erik R. Venteris, Michael Q. Wang
http://greet.es.anl.gov/publication-algae-harmonization-2012
The U.S. Department of Energy's Biomass Program has begun an initiative to obtain consistent quantitative metrics for algal biofuel production to establish an 'integrated baseline' by harmonizing and combining the Program's national resource assessment (RA), techno-economic analysis (TEA), and life-cycle analysis (LCA) models. The baseline attempts to represent a plausible near-term production scenario with freshwater microalgae growth, extraction of lipids, and conversion via hydroprocessing to produce a renewable diesel (RD) blendstock. Differences in the prior TEA and LCA models were reconciled (harmonized) and the RA model was used to prioritize and select the most favorable consortium of sites that supports production of 5 billion gallons per year of RD. Aligning the TEA and LCA models produced slightly higher costs and emissions compared to the pre-harmonized results. However, after then applying the productivities predicted by the RA model (13 g/m2/d on annual average vs. 25 g/m2/d in the original models), the integrated baseline resulted in markedly higher costs and emissions. The relationship between performance (cost and emissions) and either productivity or lipid fraction was found to be non-linear, and important implications on the TEA and LCA results were observed after introducing seasonal variability from the RA model. Increasing productivity and lipid fraction alone was insufficient to achieve cost and emission targets; however, combined with lower energy, less expensive alternative technology scenarios, emissions and costs were substantially reduced.
Life Cycle Analysis of Alternative Aviation Fuels in GREET
A. Elgowainy, J. Han, M. Wang, N. Carter, R. Stratton, J. Hileman, A. Malwitz, S. Balasubramanian
http://greet.es.anl.gov/publication-aviation-lca
Life Cycle Material Data Update for GREET Model
G. Keoleian, S. Miller, R. De Kleine, A. Fang, J. Mosley
July 9, 2012 revised on: July 30, 2012
http://greet.es.anl.gov/publication-greet2-lca-update
Updated Vehicle Specifications in the GREET Vehicle-Cycle Model
July 30, 2012 revised on: July 30, 2012
http://greet.es.anl.gov/publication-update-veh-specs
Alternative transportation fuels and advanced vehicle technologies are being promoted to help reduce local air pollution, greenhouse gas emissions, and the United States dependence on imported oil. To more accurately and completely evaluate the energy and emissions effects of alternative fuels and vehicle technologies, researchers should consider emissions and energy use from vehicle operations, fuel production processes, and vehicle production processes. This research area is especially important for technologies that employ fuels and materials with distinctly different primary energy sources and production processes, i.e., those for which upstream emissions and energy use can be significantly different. The GREET (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model was originally developed to evaluate fuel-cycle (or well-to-wheels) energy use and emissions of various transportation technologies (Wang 1999). In 2006, the GREET vehicle-cycle model was released to examine energy use and emissions of vehicle production and disposal processes (Burnham et al. 2006). This document updates the key vehicle specifications in Burnham et al. (2006) for the latest publically available version, GREET2_2012, of the vehicle-cycle model. In addition to the parameters described in this document, GREET2_2012 includes updated data on production and recycling of lithium-ion batteries, material production of several key vehicle materials, and part manufacturing and vehicle assembly (Dunn et al. 2012; Keoleian et al. 2012; Sullivan et al. 2010).
The Impact of Recycling on Cradle-to-Gate Energy Consumption and Greenhouse Gas Emissions of Automotive Lithium-Ion Batteries
Jennifer B. Dunn, Linda Gaines, John Sullivan, and Michael Q. Wang
http://pubs.acs.org/doi/abs/10.1021%2Fes302420z
http://greet.es.anl.gov/publication-recycling-batteries
This paper addresses the environmental burdens (energy consumption and air emissions, including greenhouse gases [GHGs]) of the material production, assembly, and recycling of automotive lithium-ion batteries in hybrid electric, plug-in hybrid electric, and battery electric vehicles (BEV) that use LiMn2O4 cathode material. In this analysis, we calculated the energy consumed and air emissions generated when recovering LiMn2O4, aluminum, and copper in three recycling processes (hydrometallurgical, intermediate physical, and direct physical recycling) and examined the effect(s) of closed-loop recycling on environmental impacts of battery production. We aimed to develop a U.S.-specific analysis of lithium-ion battery production and in particular sought to resolve literature discrepancies concerning energy consumed during battery assembly. Our analysis takes a process-level (versus a top-down) approach. For a battery used in a BEV, we estimated cradle-to-gate energy and GHG emissions of 75 MJ/kg battery and 5.1 kg CO2e/kg battery, respectively. Battery assembly consumes only 6% of this total energy. These results are significantly less than reported in studies that take a top-down approach. We further estimate that direct physical recycling of LiMn2O4, aluminum, and copper in a closed-loop scenario can reduce energy consumption during material production by up to 48%.
Energy consumption and greenhouse gas emissions from enzyme and yeast manufacture for corn and cellulosic ethanol production
Jennifer B. Dunn, Steffen Mueller, Michael Wang and Jeongwoo Han
http://www.springerlink.com/content/y580l882u044t120/
http://greet.es.anl.gov/publication-enzyme-yeast
Enzymes and yeast are important ingredients in the production of ethanol, yet the energy consumption and emissions ssociated with their production are often excluded from life-cycle analyses of ethanol. We provide new estimates for the energy consumed and greenhouse gases (GHGs) emitted during enzyme and yeast manufacture, including contributions from key ingredients such as starch, glucose, and molasses. We incorporated these data into Argonne National Laboratory's Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation model and observed that enzymes and yeast together contribute 1.4 and 27 % of farm-to-pump GHG emissions for corn and cellulosic ethanol, respectively. Over the course of the entire corn ethanol life cycle, yeast and enzymes contribute a negligible amount of GHG emissions, but increase GHG emissions from the cellulosic ethanol life cycle by 5.6 g CO2e/MJ.
Geothermal Life-Cycle Assessment - Part 3
http://greet.es.anl.gov/publication-lca-goethermal-III
Consumptive Water Use in the Production of Ethanol and Petroleum Gasoline
M. Wu, M. Mintz, M. Wang, S. Arora, Y. Chiu
January 1, 2009 revised on: November 8, 2012
http://greet.es.anl.gov/publication-consumptive-water
This report (updated in 2011 to include 2008 USDA FRIS irrigation survey results and 2008 crop production data, new ethanol yield, and co-product water allocation) examines the growing issue of water use in energy production by characterizing current consumptive water use in liquid fuel production. As used throughout this report, "consumptive water use" is the sum total of water input less water output that is recycled and reused for the process. The estimate applies to surface and groundwater sources for irrigation but does not include precipitation. Water requirements are evaluated for five fuel pathways: bioethanol from corn, ethanol from cellulosic feedstocks, gasoline from Canadian oil sands, Saudi Arabian crude, and U.S. conventional crude from onshore wells. Regional variations and historic trends are noted, as are opportunities to reduce water use. Recommended Citation: Wu, M., M. Mintz, M. Wang, S. Arora, and Y. Chiu. 2011. Consumptive Water Use in the Production of Ethanol and Petroleum Gasoline - 2011 Update, ANL/ESD/09-1-Update, Argonne National Laboratory, Lemont, IL U.S.A. 100 pp.
Well-to-wheels energy use and greenhouse gas emissions of ethanol from corn, sugarcane and cellulosic biomass for US use
Michael Wang, Jeongwoo Han, Jennifer B Dunn, Hao Cai and Amgad Elgowainy
http://greet.es.anl.gov/publication-wtw-ethanol-2012
Globally, bioethanol is the largest volume biofuel used in the transportation sector, with corn-based ethanol production occurring mostly in the US and sugarcane-based ethanol production occurring mostly in Brazil. Advances in technology and the resulting improved productivity in corn and sugarcane farming and ethanol conversion, together with biofuel policies, have contributed to the significant expansion of ethanol production in the past 20 years. These improvements have increased the energy and greenhouse gas (GHG) benefits of using bioethanol as opposed to using petroleum gasoline. This article presents results from our most recently updated simulations of energy use and GHG emissions that result from using bioethanol made from several feedstocks. The results were generated with the GREET (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model. In particular, based on a consistent and systematic model platform, we estimate life-cycle energy consumption and GHG emissions from using ethanol produced from five feedstocks: corn, sugarcane, corn stover, switchgrass and miscanthus. We quantitatively address the impacts of a few critical factors that affect life-cycle GHG emissions from bioethanol. Even when the highly debated land use change GHG emissions are included, changing from corn to sugarcane and then to cellulosic biomass helps to significantly increase the reductions in energy use and GHG emissions from using bioethanol. Relative to petroleum gasoline, ethanol from corn, sugarcane, corn stover, switchgrass and miscanthus can reduce life-cycle GHG emissions by 19-48%, 40-62%, 90-103%, 77-97% and 101-115%, respectively. Similar trends have been found with regard to fossil energy benefits for the five bioethanol pathways.
Updated Sugarcane Parameters in GREET1_2012, Second Revision
Jeongwoo Han, Jennifer B. Dunn, Hao Cai, Amgad Elgowainy and Michael Q. Wang
http://greet.es.anl.gov/publication-greet-updated-sugarcane
Considering water availability and wastewater resources in the development of algal bio-oil
Y.-W. Chiu and M. Wu
http://dx.doi.org/10.1002/bbb.1397
http://greet.es.anl.gov/publication-water-algal-bio-oil
Biofuels, Bioproducts and Biorefining 7 (4): 406-415
Investigation of biochemical biorefinery sizing and environmental sustainability impacts for conventional bale system and advanced uniform biomass logistics designs
A. M. Argo, E. C. D. Tan, D. Inman, M. H. Langholtz, L. M. Eaton, J. J. Jacobson, C. T. Wright, D. J. Muth, M. M. Wu, Y.-W. Chiu and R. L. Graham
http://greet.es.anl.gov/publication-biochem-bioref
The water footprint of biofuel produced from forest wood residue via a mixed alcohol gasification process
Y.-W. Chiu and M. Wu,
http://stacks.iop.org/1748-9326/8/i=3/a=035015
http://greet.es.anl.gov/publication-water-forest-residue
Environmental Research Letters 8 (3): 035015
Life cycle analysis of fuel production from fast pyrolysis of biomass
J. Han, J. Dunn, A. Elgowainy, M. Wang
http://greet.es.anl.gov/publication-lca-fpyro-2103
A well-to-wheels (WTW) analysis of pyrolysis-based gasoline was conducted and compared with petroleum gasoline. To address the variation and uncertainty in the pyrolysis pathways, probability distributions for key parameters were developed with data from literature. The impacts of two different hydrogen sources for pyrolysis oil upgrading and of two bio-char co-product applications were investigated. Reforming fuel gas/natural gas for H2 reduces WTW GHG emissions by 60% (range of 55-64%) compared to the mean of petroleum fuels. Reforming pyrolysis oil for H2 increases the WTW GHG emissions reduction up to 112% (range of 97-126%), but reduces petroleum savings per unit of biomass used due to the dramatic decline in the liquid fuel yield. Thus, the hydrogen source causes a trade-off between GHG reduction per unit fuel output and petroleum displacement per unit biomass used. Soil application of biochar could provide significant carbon sequestration with large uncertainty.
Modeling state-level soil carbon emission factors under various scenarios for direct land use change associated with United States biofuel feedstock production
H Kwon, S Mueller, JB Dunn, M Wander
http://greet.es.anl.gov/publication-state-soil-carbon
Current estimates of life cycle greenhouse gas emissions of biofuels produced in the US can be improved by refining soil C emission factors (EF; C emissions per land area per year) for direct land use change associated with different biofuel feedstock scenarios. We developed a modeling framework to estimate these EFs at the state-level by utilizing remote sensing data, national statistics databases, and a surrogate model for CENTURY's soil organic C dynamics submodel (SCSOC). We estimated the forward change in soil C concentration within the 0-30 cm depth and computed the associated EFs for the 2011 to 2040 period for croplands, grasslands or pasture/hay, croplands/conservation reserve, and forests that were suited to produce any of four possible biofuel feedstock systems [corn (Zea Mays L)-corn, corn-corn with stover harvest, switchgrass (Panicum virgatum L), and miscanthus (Miscanthus × giganteus Greef et Deuter)]. Our results predict smaller losses or even modest gains in sequestration for corn based systems, particularly on existing croplands, than previous efforts and support assertions that production of perennial grasses will lead to negative emissions in most situations and that conversion of forest or established grasslands to biofuel production would likely produce net emissions. The proposed framework and use of the SCSOC provide transparency and relative simplicity that permit users to easily modify model inputs to inform biofuel feedstock production targets set forth by policy.
Energy consumption during the manufacture of nutrients for algae cultivation
Michael C. Johnson, Ignasi Palou-Rivera, Edward D. Frank
http://greet.es.anl.gov/publication-johnson-nutrients
The effect of nutrient production on life cycle analysis (LCA) of energy use and greenhouse gas emissions for algal biofuels can be significant, yet recent algal biofuel LCAs vary significantly in their estimates for contributions from fertilizer production. Given the uncertainty in emissions associated with fertilizer manufacturing and the possibility that they play a significant role in algae LCA, this report examined nitrogen and phosphorus fertilizer production in the U.S. byway of a detailed examination and analysis of published data.We found that the energy use and emissions of algae fertilizers derive fromthe manufacturing of just a fewkey reagents, namely ammonia and phosphoric acid. Under the assumption that large-scale algae growth will utilize commodity chemicals, the life cycle inventory centers on a few processes. We report relatively consistent values in the literature for these processes, suggest representative values to use in future LCA work, and discuss proper handling of fossil carbon in urea
Greet 2016 Model
http://greet.es.anl.gov/publication-greet-model
Greet 2016 Manual
http://greet.es.anl.gov/publication-greet-manual
Updated Emission Factors of Air Pollutants from Vehicle Operations in GREET Using MOVES
Hao Cai, Andrew Burnham, Michael Wang
http://greet.es.anl.gov/publication-vehicles-13
Development of Tallow-based Biodiesel Pathway in GREET
Jeongwoo Han, Amgad Elgowainy, and Michael Wang
http://greet.es.anl.gov/publication-tallow-13
Life-cycle energy use and greenhouse gas emissions of production of bioethanol from sorghum in the United States
Hao Cai, Jennifer B Dunn, Zhichao Wang, Jeongwoo Han and Michael Q Wang
http://dx.doi.org/10.1186/1754-6834-6-141
http://greet.es.anl.gov/publication-sorghum-13
Background: The availability of feedstock options is a key to meeting the volumetric requirement of 136.3 billion liters of renewable fuels per year beginning in 2022, as required in the US 2007 Energy Independence and Security Act. Life-cycle greenhouse gas (GHG) emissions of sorghum-based ethanol need to be assessed for sorghum to play a role in meeting that requirement.
Life Cycle Analysis of Conventional and Alternative Marine Fuels in GREET
Felix Adom, Jennifer B. Dunn, Amgad Elgowainy, Jeongwoo Han, Michael Wang
http://greet.es.anl.gov/publication-marine-fuels-13
Updated Greenhouse Gas and Criteria Air Pollutant Emission Factors of the U.S. Electric Generating Units in 2010
Hao Cai, Michael Wang, Amgad Elgowainy, Jeongwoo Han
http://greet.es.anl.gov/publication-electricity-13
Updates to Parameters of Hydrogen Production Pathways in GREET
Amgad Elgowainy, Jeongwoo Han, and Hao Zhu
http://greet.es.anl.gov/publication-h2-13
Update to Transportation Parameters in GREET
Jennifer B. Dunn, Amgad Elgowainy, Anant Vyas, Pu Lu, Jeongwoo Han, Michael Wang
http://greet.es.anl.gov/publication-tansportation-distribution-13
Analysis of Petroleum Refining Energy Efficiency of U.S. Refineries
Hao Cai, Jeongwoo Han, Grant Forman, Vince Divita, Amgad Elgowainy, Michael Wang
http://greet.es.anl.gov/publication-petroleum-eff-13
Material and Energy Flows in the Production of Cellulosic Feedstocks for Biofuels for GREET1_2013
Zhichao Wang, Jennifer B. Dunn, Jeongwoo Han, and Michael Q. Wang
http://greet.es.anl.gov/publication-feedstocks-13
AFLEET Manual
http://greet.es.anl.gov/publication-afleet-manual
Analysis of Riverine Sediment and Nutrient Exports in Missouri River Basin by Application of SWAT Model
Zhonglong Zhang, May Wu
http://greet.es.anl.gov/publication-morb-swat
Effects of co-produced biochar on life cycle greenhouse gas emissions of pyrolysis-derived renewable fuels
Zhichao Wang, Jennifer B. Dunn, Jeongwoo Han and Michael Q. Wang
http://onlinelibrary.wiley.com/doi/10.1002/bbb.1447/abstract
http://greet.es.anl.gov/publication-biochar-pyrolysis-2013
Supply Chain Sustainability Analysis of Three Biofuel Pathways
J. Dunn, M. Johnson, Z. Wang, M. Wang
http://greet.es.anl.gov/publication-scsa-2014
Investigating Grey Water Footprint for the Production of Gasoline and Diesel from Biomass via Fast Pyrolysis
May Wu
http://greet.es.anl.gov/publication-grey-water-footprint
Cost of ownership and well-to-wheels carbon emissions/oil use of alternative fuels and advanced light-duty vehicle technologies
A. Elgowainy,A. Rousseau, M. Wang, M. Ruth, D. Andress, J. Ward, F. Joseck, T. Nguyen, S. Das
http://greet.es.anl.gov/publication-wtw-costownership-vehicles
The use of alternative fuels and advanced light-duty vehicle (LDV) technologies is gaining momentum worldwide in order to reduce petroleum consumption and greenhouse gas emissions. The U.S. Department of Energy (DOE) has developed technical and cost targets at the component level for several advanced LDV technologies such as plug-in hybrid, battery electric, and fuel cell electric vehicles as well as cost targets for low-carbon fuels. DOE, Argonne National Laboratory (Argonne), and the National Renewable Energy Laboratory (NREL) recently updated their analysis of well-to-wheels (WTW) greenhouse gases (GHG) emissions, petroleum use, and the cost of ownership of vehicle technologies that have the potential to significantly reduce GHG emissions and petroleum consumption. A comprehensive assessment of how these alternative fuels and vehicle technologies options could cost-effectively meet the future carbon emissions and oil consumption targets has been conducted. This paper estimates the ownership cost and the potential reduction of WTW carbon emissions and oil consumption associated with alternative fuels and advanced LDV technologies. Efficient LDVs and low-carbon fuels can contribute to a substantial reduction in GHG emissions from the current 200-230 g/km for typical compact (small family) size diesel and gasoline vehicles. With RD&D success, the ownership costs of various advanced powertrains deployed in the 2035 time frame will likely converge, thus enhancing the probability of their market penetration. To attain market success, it is necessary that public and private sectors coordinate RD&D investments and incentive programs aiming at both reducing the cost of advanced vehicle technologies and establishing required fuel infrastructures.
A Spatial Modeling Framework to Evaluate Domestic Biofuel-Induced Potential Land Use Changes and Emissions
Joshua Elliott, Bhavna Sharma, Neil Best, Michael Glotter, Jennifer B. Dunn, Ian Foster, Fernando Miguez, Steffen Mueller, and Michael Wang
http://pubs.acs.org/doi/abs/10.1021/es404546r
http://greet.es.anl.gov/publication-domestic-luc
We present a novel bottom-up approach to estimate biofuel-induced land-use change (LUC) and resulting CO2 emissions in the U.S. from 2010 to 2022, based on a consistent methodology across four essential components: land availability, land suitability, LUC decision-making, and induced CO2 emissions. Using high-resolution geospatial data and modeling, we construct probabilistic assessments of county-, state-, and national-level LUC and emissions for macroeconomic scenarios. We use the Cropland Data Layer and the Protected Areas Database to characterize availability of land for biofuel crop cultivation, and the CERES-Maize and BioCro biophysical crop growth models to estimate the suitability (yield potential) of available lands for biofuel crops. For LUC decisionmaking, we use a county-level stochastic partial-equilibrium modeling framework and consider five scenarios involving annual ethanol production scaling to 15, 22, and 29 BG, respectively, in 2022, with corn providing feedstock for the first 15 BG and the remainder coming from one of two dedicated energy crops. Finally, we derive high-resolution above-ground carbon factors from the National Biomass and Carbon Data set to estimate emissions from each LUC pathway. Based on these inputs, we obtain estimates for average total LUC emissions of 6.1, 2.2, 1.0, 2.2, and 2.4 gCO2e/MJ for Corn-15 Billion gallons (BG), Miscanthus × giganteus (MxG)-7 BG, Switchgrass (SG)-7 BG, MxG-14 BG, and SG-14 BG scenarios, respectively
Oil Sands Energy Intensity Analysis for GREET Model Update
J. Englander, A Brandt
http://greet.es.anl.gov/publication-lca-update-oil-sands
Spatial and Temporal Analysis of Land Use Disturbance and Greenhouse Gas Emissions From Canadian Oil Sands Production
S Yeh, A. Zhao, S Hogan
http://greet.es.anl.gov/publication-luc-canadian-os
Energy Efficiency and Greenhouse Gas Emission Intensity of Petroleum Products at U.S. Refineries
A. Elgowainy, J. Han, H. Cai, M. Wang, G. S. Forman, V. B. DiVita
http://greet.es.anl.gov/publication-energy-efficiency-refineries
This paper describes the development of (1) a formula correlating the variation in overall refinery energy efficiency with crude quality, refinery complexity, and product slate; and (2) a methodology for calculating energy and greenhouse gas (GHG) emission intensities and processing fuel shares of major U.S. refinery products. Overall refinery energy efficiency is the ratio of the energy present in all product streams divided by the energy in all input streams. Using linear programming (LP) modeling of the various refinery processing units, we analyzed 43 refineries that process 70% of total crude input to U.S. refineries and cover the largest four Petroleum Administration for Defense District (PADD) regions (I, II, III, V). Based on the allocation of process energy among products at the process unit level, the weighted-average product-specific energy efficiencies (and ranges) are estimated to be 88.6% (86.2%-91.2%) for gasoline, 90.9% (84.8%-94.5%) for diesel, 95.3% (93.0%-97.5%) for jet fuel, 94.5% (91.6%-96.2%) for residual fuel oil (RFO), and 90.8% (88.0%-94.3%) for liquefied petroleum gas (LPG). The corresponding weighted-average, production GHG emission intensities (and ranges) (in grams of carbon dioxide-equivalent (CO2e) per megajoule (MJ)) are estimated to be 7.8 (6.2-9.8) for gasoline, 4.9 (2.7-9.9) for diesel, 2.3 (0.9-4.4) for jet fuel, 3.4 (1.5-6.9) for RFO, and 6.6 (4.3-9.2) for LPG. The findings of this study are key components of the life-cycle assessment of GHG emissions associated with various petroleum fuels; such assessment is the centerpiece of legislation developed and promulgated by government agencies in the United States and abroad to reduce GHG emissions and abate global warming.
U.S. Refinery Efficiency: Impacts Analysis and Implications for Fuel Carbon Policy Implementation
G. S. Forman, V. B. Divita, J. Han, H. Cai, A. Elgowainy, M. Wang
http://pubs.acs.org/doi/abs/10.1021/es501035a
http://greet.es.anl.gov/publication-us-refineries-efficiency
In the next two decades, the U.S. refining industry will face significant changes resulting from a rapidly evolving domestic petroleum energy landscape. The rapid influx of domestically sourced tight light oil and relative demand shifts for gasoline and diesel will impose challenges on the ability of the U.S. refining industry to satisfy both demand and quality requirements. This study uses results from Linear Programming (LP) modeling data to examine the potential impacts of these changes on refinery, process unit, and product-specific efficiencies, focusing on current baseline efficiency values across 43 existing large U.S. refineries that are operating today. These results suggest that refinery and product-specific efficiency values are sensitive to crude quality, seasonal and regional factors, and refinery configuration and complexity, which are determined by final fuel specification requirements. Additional processing of domestically sourced tight light oil could marginally increase refinery efficiency, but these benefits could be offset by crude rebalancing. The dynamic relationship between efficiency and key parameters such as crude API gravity, sulfur content, heavy products, residual upgrading, and complexity are key to understanding possible future changes in refinery efficiency. Relative to gasoline, the efficiency of diesel production is highly variable, and is influenced by the number and severity of units required to produce diesel. To respond to future demand requirements, refiners will need to reduce the gasoline/diesel (G/D) production ratio, which will likely result in greater volumes of diesel being produced through less efficient pathways resulting in reduced efficiency, particularly on the marginal barrel of diesel. This decline in diesel efficiency could be offset by blending of Gas to Liquids (GTL) diesel, which could allow refiners to uplift intermediate fuel streams into more efficient diesel production pathways, thereby allowing for the efficient production of incremental barrels of diesel without added capital investment for the refiner. Given the current wide range of refinery carbon intensity values of baseline transportation fuels in LCA models, this study has shown that the determination of refinery, unit, and product efficiency values requires careful consideration in the context of specific transportation fuel GHG policy objectives.
Comments on Ethanol's Broken Promise by the Environmental Working Group (May 2014)
Michael Wang, Jennifer B. Dunn, Steffen Mueller, Zhangcai Qin, Wally Tyner, and Barry Goodwin
http://greet.es.anl.gov/publication-Comments-Ethanol-Broken-Promise-EWG
In their recent report, the Environmental Working Group (EWG) posited that the life-cycle emissions of corn ethanol are greater than those of gasoline. EWG concluded that lowering the ethanol mandate under the Renewable Fuel Standard (RFS) by the United States Environmental Protection Agency (EPA) would reduce greenhouse gas (GHG) emissions by 3 million tons of CO2 equivalents (CO2e) in 2014. The EWG report was organized into three sections. First, EWG maintained that a significant amount of grasslands and wetlands were converted to corn farming between 2008 and 2012. This conclusion was based on two EWG earlier reports that used U.S. Department of Agriculture's (USDA's) Cropland Data Layer (CDL) and satellite data. EWG then applied the emission factors of land conversions from earlier work by Plevin et al. to estimate total emissions associated with conversion of grasslands and wetlands to corn farms. The land areas EWG estimated to have been converted to wetlands and grasslands are high compared to earlier detailed studies and modeling results. Further, the emission factors they applied are high compared to those in other reports and studies that take into account important variations in initial and final land states. Most importantly, the emission factor EWG applied to wetland-to-corn agriculture transitions reflects emissions from conversion of peat- and carbon-rich tropical wetlands rather than from conversion of temperate wetlands found in the United States. Conversion of U.S. temperate wetlands should be less carbon-intensive. Second, EWG used EPA's land-use change (LUC) GHG emissions results for corn ethanol for year 2012 to calculate high life-cycle GHG emissions for corn ethanol. EPA's intent for including corn ethanol LUC GHG emissions results for 2012 and 2017, however, seems to have been mostly for sensitivity analyses because these emissions were not discussed in the RFS final rule or its Regulatory Impact Analysis (RIA). Further, 2012 emissions were not calculated for all biofuel pathways included in RFS. In their report, EWG picked the EPA 2012 GHG emissions for corn ethanol and applied them to the EPA-proposed reduced volume for corn ethanol in 2014 to make the erroneous conclusion that the proposal resulted in 3 million tonnes of CO2 reduction in 2014. Finally, EWG stated that Argonne National Laboratory's Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREETTM) model uses unrealistic assumptions in estimating LUC associated with increased corn ethanol production. EWG confused parameters in GREET with those in an economic model, the Global Trade Analysis Project (GTAP). The particular parameter EWG discussed, the yield-price elasticity, in the GTAP model is supported by a recent analysis. In the discussion below, we address in detail each of these three areas and several other issues in the EWG report.
Integrated Evaluation of Cost, Emissions, and Resource Potential for Algal Biofuels at the National Scale
Ryan E. Davis, Daniel B. Fishman, Edward D. Frank, Michael C. Johnson, Susanne B. Jones, Christopher M. Kinchin, Richard L. Skaggs, Erik R. Venteris, Mark S. Wigmosta
http://greet.es.anl.gov/publication-integrated-cost-algal-biofuels
Costs, emissions, and resource availability were modeled for the production of 5 billion gallons yr-1 (5 BGY) of renewable diesel in the United States from Chlorella biomass by hydrothermal liquefaction (HTL). The HTL model utilized data from a continuous 1-L reactor including catalytic hydrothermal gasification of the aqueous phase, and catalytic hydrotreatment of the HTL oil. A biophysical algae growth model coupled with weather and pond simulations predicted biomass productivity from experimental growth parameters, allowing site-by-site and temporal prediction of biomass production. The 5 BGY scale required geographically and climatically distributed sites. Even though screening down to 5 BGY significantly reduced spatial and temporal variability, site-to-site, season-to-season, and interannual variations in productivity affected economic and environmental performance. Performance metrics based on annual average or peak productivity were inadequate; temporally and spatially explicit computations allowed more rigorous analysis of these dynamic systems. For example, 3-season operation with a winter shutdown was favored to avoid high greenhouse gas emissions, but economic performance was harmed by underutilized equipment during slow-growth periods. Thus, analysis of algal biofuel pathways must combine spatiotemporal resource assessment, economic analysis, and environmental analysis integrated over many sites when assessing national scale performance.
Infrastructure associated emissions for renewable diesel production from microalgae
Christina E. Canter, Ryan Davis, Meltem Urgun-Demirtas, Edward D. Frank
http://greet.es.anl.gov/publication-infrastructure-rdiesel-microalgae
Greenhouse gas (GHG) emissions for microalgae biofuel infrastructure are sometimes neglected during a life-cycle analysis (LCA). Construction materials were found for a baseline facility designed to produce renewable diesel in the United States. Material use was amortized over the material lifetime of thirty years and then, using emission factors available in GREET 2, energy use and GHG emissions were found per MJ of renewable diesel (MJ RD). For the baseline, infrastructure GHG emissions were 8.9 gCO2e/MJ RD. Plastic and concrete had the largest emissions, and the growth ponds used the most materials of any unit operation. Fossil fuels comprised 97% of all energy use, which came predominately from natural gas at 0.090 MJ/MJ RD. A sensitivity analysis showed that changes to the pond liner thickness and material lifetime had the largest effects with the lifetime increasing the GHG emissions 28% over the baseline. Increasing the productivity (up to 50 g/m2/d) or lipid content (up to 50 wt.%) decreased the emissions. Infrastructure emissions were compared to those from the fuel-cycle of a reduced emission scenario, showing that infrastructure related emissions ranged from 17% to 57% of the fuel-cycle emissions, with higher values at lower productivities.
Response to 'Biofuels from crop residue can reduce soil carbon and increase CO2 emissions'
J. B. Dunn, Z. Qin, M. Wang
http://greet.es.anl.gov/publication-response-biofuels
Updated Fugitive Greenhouse Gas Emissions for Natural Gas Pathways in the GREET
A. Burnham, J. Han, A. Elgowainy, and M. Wang
October 25, 2013 revised on: June 25, 2014
http://greet.es.anl.gov/publication-ch4-updates-13
Updated Vented, Flaring, and Fugitive Greenhouse Gas Emissions for Crude Oil Production in the GREET Model
H. Cai, J. Han, A. Elgowainy, M. Wang
http://greet.es.anl.gov/publication-emissions-crude-oil-2014
Update to Soybean Farming and Biodiesel Production in GREET
J. Han, A. Elgowainy, H. Cai, M. Wang
http://greet.es.anl.gov/publication-soybean-biodiesel-2014
Updated Fugitive Grenhouse Gas Emissions for Natural Gas Pathways in the GREET Model
A. Burnham, J. Han, A. Elgowainy, M. Wang
http://greet.es.anl.gov/publication-emissions-ng-2014
GREET Pretreatment Module
F. Adom, J. Dunn, J. Han
http://greet.es.anl.gov/publication-pretreatment-module
Updates to the Corn Ethanol Pathway and Development of an Integrated Corn and Corn Stover Ethanol Pathway in the GREET Model
Z. Wang, J. Dunn, M. Wang
http://greet.es.anl.gov/publication-update-corn-ethanol-2014
Rail Module Expansion in GREET
J. Han, H. Chen, A. Elgowainy, A. Vyas, M. Wang
http://greet.es.anl.gov/publication-rail-module
Updated enzyme and yeast assumptions
J. Dunn
http://greet.es.anl.gov/publication-enzyme-yeast-2014
Contribution of Infrastructure to Oil and Gas Production and Processing Carbon Footprint
J. Beath, N. Black, M. Boone, G. Roberts, B. Rutledge, A. Elgowainy, M. Wang, J. Kelly
http://greet.es.anl.gov/publication-oil-gas-prod-infra
Consideration of Black Carbon and Primary Organic Carbon Emissions in Life-Cycle Analysis of Greenhouse Gas Emissions of Vehicle Systems and Fuels
H. Cai, and M. Wang
http://pubs.acs.org/doi/pdf/10.1021/es503852u
http://greet.es.anl.gov/publication-black-carbon-2014
Material and Energy Flows in the Materials Production, Assembly, and End-of-Life Stages of the Automotive Lithium-Ion Battery Life Cycle
J. Dunn, L. Gaines, M. Barnes, J. Sullivan, M. Wang
http://greet.es.anl.gov/publication-li-ion
Estimation of Emission Factors of Particulate Black Carbon and Organic Carbon from Stationary, Modile, and Non-point Sources in the United States for Incorporation into GREET
H. Cai, M. Wang
http://greet.es.anl.gov/publication-black-carbon-greet
Addition of New Conventional and Lightweight Vehicle Models in the GREET Model
J. Kelly, A. Burnham, J. Sullivan, A. Elgowainy, M. Wang
http://greet.es.anl.gov/publication-vehicle-additions-2014
Lightweight Materials for Automotive Applications
M.C. Johnson, J.L. Sullivan
http://greet.es.anl.gov/publication-lightweight-automotive
Update of the CO2 Emission Factor from Agricultural Liming
H. Cai, M. Wang, J. Han
http://greet.es.anl.gov/publication-co2-lming
Stationary Combustion Emission Factors Update
ERG for Argonne
http://greet.es.anl.gov/publication-emission-factors-2014
Developing Country-Level Water Footprints of Biofuel Produced from Switchgrass and Miscanthus x Giganteus in the United States
M. Wu, Y.W. Chiu
http://greet.es.anl.gov/publication-country-level-water-footprint
Perennial grass has been proposed as a potential candidate for producing cellulosic biofuel because of its promising productivity and benefits to water quality, and because it is a non-food feedstock. While extensive research focuses on selecting and developing species and conversion technologies, the impact of grass-based biofuel production on water resources remains less clear. As feedstock growth requires water and the type of water consumed may vary considerably from region to region, water use must be characterized with spatial resolution and on a fuel production basis. This report summarizes a study that assesses the impact of biofuel production on water resource use and water quality at county, state, and regional scales by developing a water footprint of biofuel produced from switchgrass and Miscanthus × giganteus via biochemical conversion. Estimates of the blue, green, and gray water footprints of these perennial biofuels were conducted at the county level for the U.S. On the basis of the feedstock resource production potential projected in the U.S. Billion-Ton Update [USDOE 2011], a series of feedstock production scenarios is analyzed. The perennial-grass-based biofuel pathway is examined under six biomass resource projection scenarios, for the years 2022 and 2030 at farm-gate prices of $40, $60, and $80 per dry short ton of feedstock.
Life-Cycle Fossil Energy Consumption and Greenhouse Gas Emissions of Bioderived Chemicals and Their Conventional Counterparts
Felix Adom, Jennifer B. Dunn, Jeongwoo Han, and Norm Sather
http://pubs.acs.org/doi/abs/10.1021/es503766e
http://greet.es.anl.gov/publication-bio-chem
Biomass-derived chemical products may offer reduced environmental impacts compared to their fossil-derived counterparts and could improve profit margins at biorefineries when coproduced with higher-volume, lower-profit margin biofuels. It is important to assess on a life-cycle basis the energy and environmental impacts of these bioproducts as compared to conventional, fossil-derived products. We undertook a life-cycle analysis of eight bioproducts produced from either algal-derived glycerol or corn stover-derived sugars. Selected on the basis of technology readiness and market potential, the bioproducts are propylene glycol, 1,3-propanediol, 3-hydroxypropionic acid, acrylic acid, polyethylene, succinic acid, isobutanol, and 1,4-butanediol. We developed process simulations to obtain energy and material flows in the production of each bioproduct and examined sensitivity of these flows to process design assumptions. Conversion process data for fossil-derived products were based on the literature. Conversion process data were combined with upstream parameters in the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model to generate life-cycle greenhouse gas (GHG) emissions and fossil energy consumption (FEC) for each bioproduct and its corresponding petroleum-derived product. The bioproducts uniformly offer GHG emissions reductions compared to their fossil counterparts ranging from 39 to 86% on a cradle-to-grave basis. Similarly, FEC was lower for bioproducts than for conventional products.
The significance of Li-ion batteries in electric vehicle life-cycle energy and emissions and recycling's role in its reduction
J. B. Dunn, L. Gaines, J. C. Kelly, C. James, K. G. Gallagher
http://pubs.rsc.org/en/content/articlehtml/2014/ee/c4ee03029j
http://greet.es.anl.gov/publication-lion-ev
Three key questions have driven recent discussions of the energy and environmental impacts of automotive lithium-ion batteries. We address each of them, beginning with whether the energy intensity of producing all materials used in batteries or that of battery assembly is greater. Notably, battery assembly energy intensity depends on assembly facility throughput because energy consumption of equipment, especially the dry room, is mainly throughput-independent. Low-throughput facilities therefore will have higher energy intensities than near-capacity facilities. In our analysis, adopting an assembly energy intensity reflective of a low-throughput plant caused the assembly stage to dominate cradle-to-gate battery energy and environmental impact results. Results generated with an at-capacity assembly plant energy intensity, however, indicated cathode material production and aluminium use as a structural material were the drivers. Estimates of cradle-to-gate battery energy and environmental impacts must therefore be interpreted in light of assumptions made about assembly facility throughput. The second key question is whether battery recycling is worthwhile if battery assembly dominates battery cradle-to-gate impacts. In this case, even if recycled cathode materials are less energy and emissions intensive than virgin cathode materials, little energy and environmental benefit is obtained from their use because the energy consumed in assembly is so high. We reviewed the local impacts of metals recovery for cathode materials and concluded that avoiding or reducing these impacts, including SOx emissions and water contamination, is a key motivator of battery recycling regardless of the energy intensity of assembly. Finally, we address whether electric vehicles (EV) offer improved energy and environmental performance compared to internal combustion-engine vehicles (ICV). This analysis illustrated that, even if a battery assembly energy reflective of a low-throughput facility is adopted, EVs consume less petroleum and emit fewer greenhouse gases (GHG) than an ICV on a life-cycle basis. The only scenario in which an EV emitted more GHGs than an ICV was when it used solely coal-derived electricity as a fuel source. SOx emissions, however, were up to four times greater for EVs than ICVs. These emissions could be reduced through battery recycling.
Research Note: Revision of Parameters of the Grain Sorghum Ethanol Pathway in GREET
H. Cai, M. Wang, J. Dunn
http://greet.es.anl.gov/publication-note-sorghum-parameters
We recently reviewed publications and data concerning sorghum farming to revise several grain sorghum ethanol pathway parameters in the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREETTM) model. In this research note, we present our revision of sorghum grain yields, the grain sorghum harvested-to-planted acreage ratio, the grain sorghum stover nitrogen content, and nitrogen fertilizer application rates. The latter two parameters are very important because previous GREET life-cycle analysis concluded that nitrous oxide emissions from nitrogen fertilizer application and from decay of residual grain sorghum stover in the field are major contributors to the life-cycle greenhouse gas (GHG) emissions of grain sorghum ethanol (Cai et al., 2013).
Soil carbon sequestration and land use change associated with biofuel production: Empirical evidence
Zhangcai Qin, Jennifer B. Dunn, Hoyoung Kwon, Steffen Mueller, Michelle M. Wander
http://dx.doi.org/10.1111/gcbb.12237
http://greet.es.anl.gov/publication-soc-luc-empirical
Soil organic carbon (SOC) change can be a major impact of land use change (LUC) associated with biofuel feedstock production. By collecting and analyzing data from worldwide field observations of major LUCs from cropland, grassland and forest to lands producing biofuel crops (i.e., corn, switchgrass, Miscanthus, poplar and willow), we were able to estimate SOC response ratios and sequestration rates and evaluate the effects of soil depth and time scale on SOC change. Both the amount and rate of SOC change were highly dependent on the specific land transition. Irrespective of soil depth or time horizon, cropland conversions resulted in an overall SOC gain of 6-14% relative to initial SOC level, while conversion from grassland or forest to corn (without residue removal) or poplar caused significant carbon loss (9-35%). No significant SOC changes were observed in land converted from grasslands or forests to switchgrass, Miscanthus or willow. The SOC response ratios were similar in both 0-30 and 0-100 cm soil depths in most cases, suggesting SOC changes in deep soil and that use of top soil only for SOC accounting in biofuel life cycle analysis (LCA) might underestimate total SOC changes. Soil carbon sequestration rates varied greatly among studies and land transition types. Generally, the rates of SOC change tended to be the greatest during the 10 years following land conversion, and had declined to approach 0 within about 20 years for most LUCs. Observed trends in SOC change were generally consistent with previous reports. Soil depth and duration of study significantly influence SOC change rates and so should be considered in carbon emission accounting in biofuel LCA. High uncertainty remains for many perennial systems and forest transitions, additional field trials and modeling efforts are needed to draw conclusions about the site- and system-specific rates and direction of change
Comments on Avoiding Bioenergy Competition for Food Crops and Land by Searchinger and Heimlich
M. Wang, J. Dunn
http://greet.es.anl.gov/publication-comments-searchinger-heimlich
Research and Development Needs to Enable the Expansion of Natural Gas Use in Transportation
Michael Wang, Brad Zigler, Yarom Polsky
http://greet.es.anl.gov/publication-rd-ng-transportation
Comments on and Discussion of The Liquid Carbon Challenge: Evolving Views on Transportation Fuels and Climate
M. Wang, W. Tyner, D. Williams, J. Dunn
http://greet.es.anl.gov/publication-comments-liquid-carbon
Comments on Cropland expansion outpaces agricultural and biofuel policies in the United States
J.B. Dunn, Steffen Mueller, Laurence Eaton
http://greet.es.anl.gov/publication-comments-cropland-expansion
Supply Chain Sustainability Analysis of Whole Algae Hydrothermal Liquefaction and Upgrading
A. K. Pegallapati, J. B. Dunn, E. D. Frank, S. Jones, Y. Zhu, L. Snowden-Swan, R. Davis, C. M. Kinchin
http://greet.es.anl.gov/publication-Algae-AHTL-SCSA
Well-to-Wheels GHG Emissions of Natural Gas Use in Transportation
M. Wang, A. Elgowainy
http://greet.es.anl.gov/publication-EERE-LCA-NG
Biomass Storage Options Influence Net Energy and Emissions of Cellulosic Ethanol
I. Emery, J. Dunn, J. Han, M. Wang
http://greet.es.anl.gov/publication-biomass-storage-cellulosic
Incremental biomass losses during the harvest and storage of energy crops decrease the effective crop yield at the biorefinery gate. These losses can affect the environmental performance of biofuels from cellulosic feedstocks by indirectly increasing agricultural inputs per unit of fuel and increasing direct emissions of pollutants during biomass decomposition in storage. In this study, we expand the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model to include parameters for harvest and storage of dry bales, bale silage, and bulk silage and examine the potential impact of the biomass supply chain on energy use and air pollutants from cellulosic ethanol from corn stover, switchgrass, and miscanthus feedstocks. A review of storage methods shows substantial differences in expected losses (4.2 to 16.0 %) and variability. Model results indicate that inclusion of feedstock harvest and storage pathways increases net fossil energy consumption (0.03–0.14 MJ/MJ) and greenhouse gas emissions (2.3–10 g CO2e/MJ) from cellulosic ethanol compared to analyses that exclude feedstock losses, depending on the storage scenario selected. Greenhouse gas emissions were highest from bulk ensiled silage and bale silage pathways, driven by direct emissions of greenhouse gasses during storage and material use, respectively. Storage of dry bales indoors or under cover minimizes emissions. This report emphasizes the need to increase the detail of biofuel production models and address areas of great uncertainty in the biomass supply chain, such as biomass decomposition emissions and dry matter losses.
Well-to-wheels Analysis of High Octane Fuels
J. Han, A. Elgowainy, M. Wang, V. DiVita
http://greet.es.anl.gov/publication-high-octane-various-shares
Policy Implications of Allocation Methods in the Life Cycle Analysis of Integrated Corn and Corn Stover Ethanol Production
C. Canter, J. Dunn, J. Han, Z. Wang, M. Wang
http://link.springer.com/article/10.1007/s12155-015-9664-4#
http://greet.es.anl.gov/publication-allocation-methods-corn-stover-ethanol
A biorefinery may produce multiple fuels from more than one feedstock. The ability of these fuels to qualify as one of the four types of biofuels under the US Renewable Fuel Standard and to achieve a low carbon intensity score under California's Low Carbon Fuel Standard can be strongly influenced by the approach taken to their life cycle analysis (LCA). For example, in facilities that may co-produce corn grain and corn stover ethanol, the ethanol production processes can share the combined heat and power (CHP) that is produced from the lignin and liquid residues from stover ethanol production. We examine different LCA approaches to corn grain and stover ethanol production considering different approaches to CHP treatment. In the baseline scenario, CHP meets the energy demands of stover ethanol production first, with additional heat and electricity generated sent to grain ethanol production. The resulting greenhouse gas (GHG) emissions for grain and stover ethanol are 57 and 25 g-CO2eq/MJ, respectively, corresponding to a 40 and 74 % reduction compared to the GHG emissions of gasoline. We illustrate that emissions depend on allocation of burdens of CHP production and corn farming, along with the facility capacities. Co-product handling techniques can strongly influence LCA results and should therefore be transparently documented
Impacts of Vehicle Weight Reduction via Material Substitution on Life-Cycle Greenhouse Gas Emissions
J. Kelly, J. Sullivan, A. Burnham, A. Elgowainy
https://doi.org/10.1021/acs.est.5b03192
http://greet.es.anl.gov/publication-weight-reduction-emissions
This study examines the vehicle-cycle and vehicle total life-cycle impacts of substituting lightweight materials into vehicles. We determine part-based greenhouse gas (GHG) emission ratios by collecting material substitution data and evaluating that alongside known mass-based GHG ratios (using and updating Argonne National Laboratory's GREET model) associated with material pair substitutions. Several vehicle parts are lightweighted via material substitution, using substitution ratios from a U.S. Department of Energy report, to determine GHG emissions. We then examine fuel-cycle GHG reductions from lightweighting. The fuel reduction value methodology is applied using FRV estimates of 0.15–0.25, and 0.25–0.5 L/(100km·100 kg), with and without powertrain adjustments, respectively. GHG breakeven values are derived for both driving distance and material substitution ratio. While material substitution can reduce vehicle weight, it often increases vehicle-cycle GHGs. It is likely that replacing steel (the dominant vehicle material) with wrought aluminum, carbon fiber reinforced plastic (CRFP), or magnesium will increase vehicle-cycle GHGs. However, lifetime fuel economy benefits often outweigh the vehicle-cycle, resulting in a net total life-cycle GHG benefit. This is the case for steel replaced by wrought aluminum in all assumed cases, and for CFRP and magnesium except for high substitution ratio and low FRV.
Life-cycle Analysis of Bioproducts and Their Conventional Counterparts in GREET
J. Dunn, F. Adom, N. Sather, J. Han, S. Snyder
October 3, 2014 revised on: September 30, 2015
http://greet.es.anl.gov/publication-bioproducts-lca
Incorporating Agricultural Management Practices into the Assessment of Soil Carbon Change and Life-Cycle Greenhouse Gas Emissions of Corn Stover Ethanol Production
Z. Qin, C. Canter, J.B. Dunn, S. Mueller, H. Kwon, J. Han, M. Wander, M. Wang
http://greet.es.anl.gov/publication-cclub-land-management
Material and Energy Flows in the Production of Macro and Micronutrients, Buffers, and Chemicals used in Biochemical Processes for the Production of Fuels and Chemicals from Biomass
F. Adom and J. Dunn
http://greet.es.anl.gov/publication-fuel-chemicals-biomass
Updated N2O Emissions for Soybean Fields
http://greet.es.anl.gov/publication-update-n2o-soybean
Development of the GREET Catalyst Module
Z. Wang, P.T. Benavides, J. Dunn, D. Cronauer
http://greet.es.anl.gov/publication-catalyst-module
Vehicle Materials: Material Composition of Powertrain Systems
J. Sullivan, J. Kelly, and A. Elgowainy
http://greet.es.anl.gov/publication-2015-powertrain-materials
Updated Fugitive Greenhouse Gas Emissions for Natural Gas Pathways in the GREET 2015 Model
A. Burnham, A. Elgowainy, M. Wang
http://greet.es.anl.gov/publication-fugitive-ch4-2015
Analysis of Water Consumption Associated with Hydroelectric Power Generation in the United States
D.J. Lampert, U. Lee, H. Cai, A. Elgowainy
http://greet.es.anl.gov/publication-water-hydro
Material and Energy Flows in the Production of Cathode and Anode Materials for Lithium Ion Batteries
J. Dunn, C. James, L. Gaines, K. Gallagher, Q. Dai, J.C. Kelly
http://greet.es.anl.gov/publication-anode-cathode-liion
Material and Energy Flows Associated with Select Metals in GREET 2: Molybdenum, Platinum, Zinc, Nickel, Silicon
P.T. Benavides, Q. Dai, J. Sullivan, J.C. Kelly, J.B. Dunn
http://greet.es.anl.gov/publication-mo-pt-zn-ni-si
Addition of New Conventional and Lightweight Pickup Truck Models in the GREET Model
J. Kelly, Q. Dai, and A. Elgowainy
http://greet.es.anl.gov/publication-pickup-truck-update
Life-Cycle Analysis Update of Glass and Glass Fiber for the GREET Model
Q. Dai, J. Kelly, J. Sullivan and A. Elgowainy
http://greet.es.anl.gov/publication-glass-fiber-update
Updated Life Cycle Inventory of Copper: Imports from Chile
http://greet.es.anl.gov/publication-chilean-copper
Greet Model Emission Factors for Coal and Biomass-fired Boilers
V. Jayaram, E. Melvin, G.C. England (ENVIRON)
September 30, 2015 revised on: October 5, 2015
http://greet.es.anl.gov/publication-em-coal-bio-boiler
Well-to-Wheels Greenhouse Gas Emissions of Canadian Oil Sands Products: Implications for U.S. Petroleum Fuels
H. Cai, A.R. Brandt, S. Yeh, J.G. Englander, J. Han, A. Elgowainy, M.Q. Wang
http://pubs.acs.org/doi/abs/10.1021/acs.est.5b01255
http://greet.es.anl.gov/publication-wtw-canadian-oil-sands
Development of a Life Cycle Inventory of Water Consumption Associated with the Production of Transportation Fuels
D. Lampert, H. Cai, Z. Wang, J. Keisman, M. Wu, J. Han, J. Dunn, E. Frank, J. Sullivan, A. Elgowainy, M. Wang
October 3, 2014 revised on: October 7, 2015
http://greet.es.anl.gov/publication-water-lca
The GREET Model Expansion for Well-to-Wheels Analysis of Heavy-Duty Vehicles
H. Cai, A. Burnham, M. Wang, W. Hang, A. Vyas
May 27, 2015 revised on: October 7, 2015
http://greet.es.anl.gov/publication-heavy-duty
Updating Parametric Assumptions on Nitrogen Fertilizers in GREET 2015
H. Cai, J. Han, M. Wang, A. Elgowainy
http://greet.es.anl.gov/publication-update-nitrogen-fertilizer
Parameters of Canola Biofuel Production Pathways in GREET
http://greet.es.anl.gov/publication-canadian-canola
Emissions for Crude Oil Production in the GREET Model
http://greet.es.anl.gov/publication-fugitive-crude
Updated Life-Cycle Analysis of Aluminum Production and Semi-Fabrication for the GREET Model
Q. Dai, J. Kelly, A. Burnham, A. Elgowainy
http://greet.es.anl.gov/publication-2015-al-update
Energy Intensity and Greenhouse Gas Emissions from Crude Oil Production in the Eagle Ford Region: Input Data and Analysis Methods
A. Ghandi, S. Yeh, A.R. Brandt, K. Vafi, H. Cai, M.Q. Wang, B.R. Scanlon, R.C. Reedy
http://greet.es.anl.gov/publication-eagle-ford-oil
Energy Intensity and Greenhouse Gas Emissions from Crude Oil Production in the Bakken Formation: Input Data and Analysis Methods
A.R. Brandt, T. Yeskoo, S. McNally, K. Vafi, H. Cai, M.Q. Wang
http://greet.es.anl.gov/publication-bakken-oil
Influence of corn oil recovery on life-cycle greenhouse gas emissions of corn ethanol and corn oil biodiesel
Z. Wang, J. B. Dunn, J. Han, M. Q. Wang
https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-015-0350-8
http://greet.es.anl.gov/publication-corn_oil_ethanol_biodiesel
Background Corn oil recovery and conversion to biodiesel has been widely adopted at corn ethanol plants recently. The US EPA has projected 2.6 billion liters of biodiesel will be produced from corn oil in 2022. Corn oil biodiesel may qualify for federal renewable identification number (RIN) credits under the Renewable Fuel Standard, as well as for low greenhouse gas (GHG) emission intensity credits under California's Low Carbon Fuel Standard. Because multiple products [ethanol, biodiesel, and distiller's grain with solubles (DGS)] are produced from one feedstock (corn), however, a careful co-product treatment approach is required to accurately estimate GHG intensities of both ethanol and corn oil biodiesel and to avoid double counting of benefits associated with corn oil biodiesel production. Results This study develops four co-product treatment methods: (1) displacement, (2) marginal, (3) hybrid allocation, and (4) process-level energy allocation. Life-cycle GHG emissions for corn oil biodiesel were more sensitive to the choice of co-product allocation method because significantly less corn oil biodiesel is produced than corn ethanol at a dry mill. Corn ethanol life-cycle GHG emissions with the displacement, marginal, and hybrid allocation approaches are similar (61, 62, and 59 g CO2e/MJ, respectively). Although corn ethanol and DGS share upstream farming and conversion burdens in both the hybrid and process-level energy allocation methods, DGS bears a higher burden in the latter because it has lower energy content per selling price as compared to corn ethanol. As a result, with the process-level allocation approach, ethanol's life-cycle GHG emissions are lower at 46 g CO2e/MJ. Corn oil biodiesel life-cycle GHG emissions from the marginal, hybrid allocation, and process-level energy allocation methods were 14, 59, and 45 g CO2e/MJ, respectively. Sensitivity analyses were conducted to investigate the influence corn oil yield, soy biodiesel, and defatted DGS displacement credits, and energy consumption for corn oil production and corn oil biodiesel production. Conclusions This study's results demonstrate that co-product treatment methodology strongly influences corn oil biodiesel life-cycle GHG emissions and can affect how this fuel is treated under the Renewable Fuel and Low Carbon Fuel Standards. Keywords Corn ethanol Corn oil recovery Biodiesel Life cycle analysis GHG emissions
Wells to wheels: water consumption for transportation fuels in the United States
D. J. Lampert, H. Cai, A. Elgowainy
http://pubs.rsc.org/is/content/articlehtml/2016/ee/c5ee03254g
http://greet.es.anl.gov/publication-wtw_water_trans_us
The sustainability of energy resources such as transportation fuels is increasingly connected to the consumption of water resources. Water is required for irrigation in the development of bioenergy, reservoir creation in hydroelectric power generation, drilling and resource displacement in petroleum and gas production, mineral extraction in mining operations, and cooling and processing in thermoelectric power generation. Vehicles powered by petroleum, electricity, natural gas, ethanol, biodiesel, and hydrogen fuel cells consume water resources indirectly through fuel production cycles, and it is important to understand the impacts of these technologies on water resources. Previous investigations of water consumption for transportation fuels have focused primarily on key processes and pathways, ignoring the impacts of many intermediate, inter-related processes used in fuel production cycles. Herein, the results of a life cycle analysis of water consumption for transportation fuels in the United States using an extensive system boundary that includes the water embedded in intermediate processing and transportation fuels are presented. The Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model provides a comprehensive framework and system boundary for transportation fuel analysis in the United States. GREET was expanded to include water consumption and used to compare the water consumed per unit energy and per km traveled in light-duty vehicles. Many alternative fuels were found to consume larger quantities of water on a per km basis than traditional petroleum pathways, and it is therefore important to consider the implications of transportation and energy policy changes on water resources in the future.
Supply Chain Sustainability Analysis of Indirect Liquefaction of Blended Biomass to Produce High Octane Gasoline
H. Cai, C.E. Canter, J.B. Dunn (ANL); E. Tan, M. Biddy, M. Talmadge (NREL); D.S. Hartley (INL); L. Snowden-Swan (PNNL)
October 5, 2015 revised on: March 31, 2016
http://greet.es.anl.gov/publication-scsa-idl-hog
Supply Chain Sustainability Analysis of Fast Pyrolysis and Hydrotreating Bio-Oil to Produce Hydrocarbon Fuels
F. Adom, H. Cai, J. Dunn, D. Hartley, E. Searcy, E. Tan, S. Jones, L. Snowden-Swan
March 16, 2015 revised on: April 4, 2016
http://greet.es.anl.gov/publication-fast-pyrolysis-scsa
AFLEET Tool - Version History
Andrew Burnham
http://greet.es.anl.gov/publication-afleet-revision-history
User Guide for AFLEET Tool 2016
http://greet.es.anl.gov/publication-afleet-tool-2016-user-guide
Cradle-to-Grave Lifecycle Analysis of U.S. Light-Duty Vehicle-Fuel Pathways: A Greenhouse Gas Emissions and Economic Assessment of Current (2015) and Future (2025-2030) Technologies
A. Elgowainy, J. Han, J. Ward, F. Joseck, D. Gohlke, A. Lindauer, T. Ramsden, M. Biddy, M. Alexander, S. Barnhart, I. Sutherland, L. Verduzco, T.J. Wallington
http://greet.es.anl.gov/publication-c2g-2016-report
This study provides a comprehensive lifecycle analysis (LCA), or cradle-to-grave (C2G) analysis, of the cost and greenhouse gas (GHG) emissions of a variety of vehicle-fuel pathways, as well as the levelized cost of driving (LCD) and cost of avoided GHG emissions. This study also estimates the technology readiness levels (TRLs) of key fuel and vehicle technologies along the pathways. The C2G analysis spans a full portfolio of midsize light-duty vehicles (LDVs), including conventional internal combustion engine vehicles (ICEVs), flexible fuel vehicles (FFVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), and fuel cell electric vehicles (FCEVs). In evaluating the vehicle-fuel combinations, this study considers both low-volume and high-volume (CURRENT TECHNOLOGY) cases (nominally 2015) and a high-volume (FUTURE TECHNOLOGY) lower-carbon case (nominally 2025–2030). For the CURRENT TECHNOLOGY case, low-volume vehicle and fuel production pathways are examined to determine costs in the near term. The pathway approach selected for this study is not necessarily constrained by practical feedstock, economic, policy, and market considerations, though only pathways of sufficient technological readiness were included. This is in contrast with a scenario approach, which postulates a specific vehicle-fuel production pathway or a mix of pathways that factor in real or hypothetical/perceived feedstock, economic, policy, and market considerations. As such, this study strictly focuses on possible vehicle-fuel combination pathways (i.e., no scenario analysis was conducted). The fuel pathways considered in this study are shown in Table ES-1. The selected fuel pathways were constrained to those deemed to be scalable to at least approximately 10% of LDV fleet demand in the future. The C2G greenhouse gas emissions evaluation was carried out by expanding and modifying the GREET (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model suite (2014 version) with inputs from industrial experts. This C2G GHG assessment includes both fuel and vehicle production life cycles. Cost assessments represent a final cost to the consumer, excluding tax on the final product (e.g., fuel sales tax) and/or credits (e.g., vehicle subsidies). Where available, current and future fuel cost estimates are from the 2015 DOE Energy Information Administration (EIA) Annual Energy Outlook (AEO). Otherwise, cost assessment is based on publicly available data and models, such as techno-economic analysis (TEA) models developed by DOE and its national laboratories, using a standard set of assumptions to ensure that evaluations are consistent across fuel pathways, although some of the biofuel pathways are evaluated based on external modeling and analysis reported in the literature. The modeling of various vehicle technologies, current and future, included powertrain configuration, component sizing, cost, and fuel economy and was performed with the Autonomie model. Autonomie is a modeling package that uses performance attributes of vehicle components to size components for a given vehicle configuration and vehicle performance attributes (e.g., time to accelerate from 0–60 mph, maximum speed, etc.), and to simulate fuel economy over various driving cycles. These fuel economies served as an input for this analysis and are presented in Table 36 and Figure 11 in Section 6.3. The component sizes and vehicle fuel economy results were incorporated into the GREET model to evaluate GHG emissions of vehicle production and fuel cycles, respectively, while the vehicle costs were used to evaluate the LCD. This report uses Autonomie manufacturing cost estimates that assume production at volume; however, it is important to recognize that the initial manufacture of advanced powertrain vehicles is likely to incur additional costs beyond those estimated at large scale. Accordingly, low-volume vehicle cost estimates of the CURRENT TECHNOLOGY case provide context for the high-volume estimates by serving as an indication of the degree to which low-volume manufacturing could affect vehicle cost, LCD, and cost of abated carbon.
Life-cycle Analysis of Energy Use, Greenhouse Gas Emissions, and Water Consumption in the 2016 MYPP Algal Biofuel Scenarios
Edward Frank, Ambica Pegallapati, Ryan Davis, Jennifer Markham, Andre Coleman, Sue Johnes, Mark Wigmosta, Yunhua Zhu
http://greet.es.anl.gov/publication-LCA-of-MYPP
Well-to-Wheels Greenhouse Gas Emission Analysis of High-Octane Fuels with Ethanol Blending: Phase II Analysis with Refinery Investment Options
Jeongwoo Han, Michael Wang, Amgad Elgowainy, Vincent DiVita
http://greet.es.anl.gov/publication-HOF-WTW
Consideration of land use change-induced surface albedo effects in life-cycle analysis of biofuels
H. Cai, J. Wang, Y. Feng, M. Wang, Z. Qin, J. Dunn
http://pubs.rsc.org/-/content/articlehtml/2016/ee/c6ee01728b
http://greet.es.anl.gov/publication-luc_albedo_biofuel
Land use change (LUC)-induced surface albedo effects for expansive biofuel production need to be quantified for improved understanding of biofuel climate impacts. We addressed this emerging issue for expansive biofuel production in the United States (U.S.) and compared the albedo effects with greenhouse gas emissions highlighted by traditional life-cycle analysis of biofuels. We used improved spatial representation of albedo effects in our analysis by obtaining over 1.4 million albedo observations from the Moderate Resolution Imaging Spectroradiometer flown on NASA satellites over a thousand counties representative of six Agro-Ecological Zones (AEZs) in the U.S. We utilized high-spatial-resolution, crop-specific cropland cover data from the U.S. Department of Agriculture and paired the data with the albedo data to enable consideration of various LUC scenarios. We simulated the radiative effects of LUC-induced albedo changes for seven types of crop covers using the Monte Carlo Aerosol, Cloud and Radiation model, which employs an advanced radiative transfer mechanism coupled with spatially and temporally resolved meteorological and aerosol conditions. These simulations estimated the net radiative fluxes at the top of the atmosphere as a result of the LUC-induced albedo changes, which enabled quantification of the albedo effects on the basis of radiative forcing defined by the Intergovernmental Panel on Climate Change for CO2 and other greenhouse gases effects. Finally, we quantified the LUC-induced albedo effects for production of ethanol from corn, miscanthus, and switchgrass in different AEZs of the U.S. Results show that the weighted national average albedo effect is a small cooling effect of −1.8 g CO2 equivalent (CO2e) for a mega-Joule (MJ) of corn ethanol, a relatively stronger warming effect of 12.1 g CO2e per MJ of switchgrass ethanol, and a small warming effect of 2.7 g CO2e per MJ of miscanthus ethanol. Significant variations in albedo-induced effects are found among different land conversions for the same biofuel, and among different AEZ regions for the same land conversion and biofuel. This spatial heterogeneity, owing to non-linear albedo dynamics and radiation processes, suggests highly variable LUC-induced albedo effects depending on geographical locations and vegetation. These findings provide new insights on potential climate effects by producing biofuels through considering biogeophysical as well as biogeochemical effects of biofuel production and use in the U.S.
Lifecycle Analysis of Renewable Natural Gas and Hydrocarbon Fuels from Wastewater Treatment Plant's Sludge
U. Lee, J. Han, M. Demirtas, M. Wang, L. Tao
http://greet.es.anl.gov/publication-sludge-2016
Wastewater treatment plants (WWTPs) produce sludge as a byproduct when they treat wastewater. In the United States, over 8 million dry tons of sludge are produced annually just from publicly owned WWTPs. Sludge is commonly treated in anaerobic digesters, which generate biogas; the biogas is then largely flared to reduce emissions of methane, a potent greenhouse gas. Because sludge is quite homogeneous and has a high energy content, it is a good potential feedstock for other conversion processes that make biofuels, bioproducts, and power. For example, biogas from anaerobic digesters can be used to generate renewable natural gas (RNG), which can be further processed to produce compressed natural gas (CNG) and liquefied natural gas (LNG). Sludge can be directly converted into hydrocarbon liquid fuels via thermochemical processes such as hydrothermal liquefaction (HTL). Currently, the environmental impacts of converting sludge into energy are largely unknown, and only a few studies have focused on the environmental impacts of RNG produced from existing anaerobic digesters. As biofuels from sludge generate high interest, however, existing anaerobic digesters could be upgraded to technology with more economic potential and more environmental benefits. The environmental impacts of using a different anaerobic digestion (AD) technology to convert sludge into energy have yet to be analyzed. In addition, no studies are available about the direct conversion of sludge into liquid fuels. In order to estimate the energy consumption and greenhouse gas (GHG) emissions impacts of these alternative pathways (sludge-to-RNG and sludge-to-liquid), this study performed a lifecycle analysis (LCA) using the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET®) model. The energy uses and GHG emissions associated with the RNG and hydrocarbon liquid are analyzed relative to the current typical sludge management case, which consists of a single-stage mesophilic digester with biogas flaring. Along with the alternative HTL process, four types of AD technologies with fuel production—single-stage mesophilic, mesophilic 2-stage, single-stage mesophilic with thermohydrolysis treatment, and mesophilic-mesophilic acid/gas phase—are studied. Results show that the sludge-to-CNG pathway via AD and the sludge-to-liquid pathway via HTL reduce GHG emissions consumptions significantly. When we compare the GHG emissions of the alternative fuel production pathways to that of the counterfactual case in terms of the amount of sludge treated, reductions in GHG emissions are 39%–80% and 87% for alternative AD and HTL, respectively. Compared to petroleum gasoline and diesel GHG emission results in terms of MJ, the renewable CNG production pathway via AD and the renewable diesel production pathway via HTL reduce GHG emissions by 193% and 46%, respectively. These large reductions are mainly due to GHG credits from avoiding GHGs under the counterfactual scenario, and/or fertilizer displacement credits. Similarly, reductions in fossil fuel use for sludge-based fuels are huge. However, well-defined counterfactual scenarios are needed because the results of the study depend on the counterfactual scenario, which might vary over time.
Update to Herbaceous and Short Rotation Woody Crops in GREET® Based on the 2016 Billion Ton Study
C. Canter, Z. Qin, H. Cai, J. Dunn, M. Wang
http://greet.es.anl.gov/publication-bts-2016
Vehicle Materials: Fuel Cell Vehicle Material Composition Update
http://greet.es.anl.gov/publication-fcv-composition-2016
Material Efficiencies and Recycling of Aluminum and Carbon Fiber Reinforced Plastics for Automotive Applications
Q. Dai, J. Kelly and A. Elgowainy
http://greet.es.anl.gov/publication-materials-automotive-2016
Life Cycle Analysis of Hydrogen Production from Non-Fossil Sources
Q. Dai, A. Elgowainy, J. Kelly, J. Han, and M. Wang
http://greet.es.anl.gov/publication-h2-nonfoss-2016
Update of Recycled Content and SF6 Emissions for Magnesium in the GREET Model
http://greet.es.anl.gov/publication-mag-update-2016
Material Composition of U.S. Light-duty Vehicles
http://greet.es.anl.gov/publication-light-duty-vehicle-2016
Updating electric grid emissions factors
J. Kelly, D. Dieffenthaler, H. Cai, and A. Elgowainy
http://greet.es.anl.gov/publication-elec-greet-net-2016
Addition of nickel cobalt aluminum (NCA) cathode material to GREET2
P. T. Benavides, Q. Dai, J. Kelly, J. B. Dunn
http://greet.es.anl.gov/publication-NCA-Cathode-2016
The Greenhouse gases, Regulate Emissions, and Energy use in Transportation (GREET®) model, vehicle cycle, contains a module to characterize the material and energy consumption associated with producing automotive lithium-ion batteries (Dunn et al. 2015). This technical memo describes the addition of a 149 kW EV battery with a nickel cobalt aluminum cathode (NCA) material and documents the methodology used to calculate the material and energy flows used in the modeling of this cathode material in GREET. NCA is a fairly common cathode material. It has high capacity, high voltage, and well established performance which make it a promising alternative cathode material in lithium-ion batteries. According to Tanaka (2015) aluminum and cobalt contribute to the thermal stability and the electrochemical properties of this type of cathode material. This cathode material, however, is expensive to produce because of the high cost of nickel and cobalt (Doeff, 2013).
Well-to-Wheels Emissions of Greenhouse Gases and Air Pollutants of Dimethyl Ether from Natural Gas and Renewable Feedstocks in Comparison with Petroleum Gasoline and Diesel in the United States and Europe
U. Lee, J. Han, M. Wang, J. Ward, E. Hicks, D. Goodwin, R. Boudreaux, P. Hanarp, H. Salsing, P. Desai, E. Varenne, P. Klintbom, W. Willems, S. L. Winkler, H. Maas, R. De Kleine, J. Hansen, T. Shim, E. Furusjö
http://papers.sae.org/2016-01-2209/
http://greet.es.anl.gov/publication-DME-US-EU-2016
Dimethyl ether (DME) is an alternative to diesel fuel for use in compression-ignition engines with modified fuel systems and offers potential advantages of efficiency improvements and emission reductions. DME can be produced from natural gas (NG) or from renewable feedstocks such as landfill gas (LFG) or renewable natural gas from manure waste streams (MANR) or any other biomass. This study investigates the well-to-wheels (WTW) energy use and emissions of five DME production pathways as compared with those of petroleum gasoline and diesel using the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET®) model developed at Argonne National Laboratory (ANL).
Water Consumption in US Petroleum Refineries
R. Henderson
http://greet.es.anl.gov/publication-refineries-water-2016
Jacobs Consultancy has reviewed the consumption of water within US oil refineries. For the purposes of this study, "consumption" of water is defined as the amount of withdrawal water which is taken into the refinery's fenceline boundaries and not returned to the environment in a liquid form, i.e., water which is chemically consumed plus water lost to evaporation.
Water Consumption Factors for Electricity Generation in the United States
U. Lee, J. Han, A. Elgowainy
http://greet.es.anl.gov/publication-wcf-2016
In many regions of the United States, water availability is of concern due to growing demand and limited supply. In these regions, water is also an essential resource for most power generation technologies. Thermal power plants, which generate 87% of the total electricity in the United States, typically require a large amount of water for cooling purposes. Depending on types of cooling technology and prime movers, water loss or "consumption" through evaporation vary significantly. Hydropower plants with reservoirs "consume" large amount of water through evaporation due to the typically large surface area of the reservoir. Because water consumption rates vary by region due to different climate conditions, regional variation of water consumption due to hydropower generation should be considered. The objective of this study is to estimate the water consumption factor (WCF) for electricity generation, which is defined as the water consumed per unit of power generation (e.g., gallons of water per kWh of generated electricity). In particular, this study evaluates the variation in WCF by region. For hydropower, water consumption from hydropower reservoirs is calculated using reservoir's surface area, state-level water evaporation data, and background evapotranspiration. Note that water consumption in multipurpose reservoirs is allocated to hydropower generation based on the share of the economic benefit of power generation among benefits from all other purposes (e.g., irrigation, flood control, navigation, etc.) Thus, the balance of water consumption is allocated among all other purposes based on their estimated economic benefits. For thermal power plants, the WCFs by types of cooling technology and prime mover are estimated. Because cooling technologies and prime mover types vary by region, the WCF for thermal power generation also exhibits regional differences. The WCFs from hydropower and thermal power generation are aggregated to the national-level and also to each North American Electric Reliability Council (NERC) utility region. The national average WCF for electricity is estimated at 0.58 gal/kWh considering the average U.S. electricity generation mix in 2015. At a facility-level, the WCFs of thermoelectricity and hydropower are 0.33 and 4.4 gal/kWh, respectively, while the shares of thermo- and hydro-power generation are 87% and 6.3%, respectively. The WCFs have been implemented in the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET®) model developed by Argonne National Laboratory. GREET is a life cycle analysis tool that evaluates energy use and emissions, as well as water consumption on a life cycle basis. This study allows researchers to analyze lifecycle water consumption for various energy production and conversion pathways. While the economic benefits approach was employed to allocate WCF to hydropower generation in multipurpose reservoirs, other approaches for estimating the hydropower WCFs are subjects for future analysis and updates to the GREET model.
Summary of Expansions, Updates, and Results in GREET® 2016 Suite of Models
http://greet.es.anl.gov/publication-summary-updates-2016
This report documents the technical content of the expansions and updates in Argonne National Laboratory's GREET® 2016 release and provides references and links to key documents related to these expansions and updates.
Industrial Wastewater Treatment in GREET® Model: Energy Intensity, Water Loss, Direct Greenhouse Gas Emissions, and Biogas Generation Potential
Q. Li, J. Han, A. Elgowainy
http://greet.es.anl.gov/publication-wastewater-2016
Expanded Emission Factors for Agricultural and Mining Equipment in GREET® Full Life-Cycle Model
Q. Li, H. Cai, J. Kelly, J. Dunn
http://greet.es.anl.gov/publication-nonroad-ef-2016
Updated Fugitive Greenhouse Gas Emissions for Natural Gas Pathways in the GREET1_2016 Model
http://greet.es.anl.gov/publication-updated-ghg-2016
Well-to-wheels analysis of the greenhouse gas emissions and energy use of vehicles with gasoline compression ignition engines on low octane gasoline-like fuel
Z. Lu, J. Han, M. Wang, H. Cai, P. Sun, D. Dieffenthaler, V. Gordillo, J.-C. Monfort, X. He, S. Przesmitzki
http://greet.es.anl.gov/publication-wtw-lof-gci
Gasoline Compression Ignition (GCI) engines using a low octane gasoline-like fuel (LOF) have good potential to achieve lower NOx and lower particulate matter emissions with higher fuel efficiency compared to the modern diesel compression ignition (CI) engines. In this work, we conduct a well-to-wheels (WTW) analysis of the greenhouse gas (GHG) emissions and energy use of the potential LOF GCI vehicle technology. A detailed linear programming (LP) model of the US Petroleum Administration for Defense District Region (PADD) III refinery system - which produces more than 50% of the US refined products - is modified to simulate the production of the LOF in petroleum refineries and provide product-specific energy efficiencies. Results show that the introduction of the LOF production in refineries reduces the throughput of the catalytic reforming unit and thus increases the refinery profit margins. The overall efficiency of the refinery does not change significantly because both the purchased energy and the refinery fuel production increase in response to the introduction of the LOF production. The refinery energy efficiency of LOF is approximately 0.8 and 1.6 percentage points higher than that of gasoline and diesel, respectively. Taking into account a 25% fuel economy gain relative to the regular gasoline internal combustion engine vehicle (ICEV), the per-mile-based WTW GHG emissions of the LOF GCI ICEV are estimated to be 22% and 9% lower than those of the today's gasoline and diesel ICEVs, respectively; and the per-mile-based WTW fossil energy use is 18% and 6% lower than gasoline and diesel ICEVs, respectively.
Update of Electric Generation Mix and Crude Oil Share
U. Lee, J. Han, H. Cai
http://greet.es.anl.gov/publication-electricity-crude-share-2016
Electricity and petroleum products from crude oil (e.g., gasoline, diesel, jet, residual oil and liquefied petroleum gas) are the baseline energy products that are used in various fuel production pathways. Therefore, the energy and emissions intensities of electricity and petroleum products are critical for life-cycle analysis (LCA) of transportations fuels, or well-to-wheels (WTW) analysis. These energy and emissions intensities of electricity and petroleum products depend highly on the electricity generation mixes and the crude oil mixes to the U.S. refineries, respectively, which change over time and vary by region. Therefore, we continuously investigate and update the electricity generation mixes and the crude oil mixes to the U.S. refineries in our LCA model (namely, the Greenhouse gases, Regulated Emissions, and Energy use in Transportation [GREET®] model). For the updates of these mixes to the GREET 2016 model, this technical memo documents the data sources and the methodologies at the national and regional levels.
Well-to-Wheels Analysis of Compressed Natural Gas and Ethanol from Municipal Solid Waste
U. Lee, J. Han, M. Wang
http://greet.es.anl.gov/publication-wte-2016
The amount of municipal solid waste (MSW) generated in the United States was estimated at 254 million wet tons in 2013, and around half of that generated waste was landfilled. There is a huge potential in recovering energy from that waste, since around 60% of landfilled material is biomass-derived waste that has high energy content. In addition, diverting waste for fuel production avoids huge fugitive emissions from landfills, especially uncontrolled CH4 emissions, which are the third largest anthropogenic CH4 source in the United States. Lifecycle analysis (LCA) is typically used to evaluate the environmental impact of alternative fuel production pathways. LCA of transportation fuels is called well-to-wheels (WTW) and covers all stages of the fuel production pathways, from feedstock recovery (well) to vehicle operation (wheels). In this study, the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET®) model developed by Argonne National Laboratory is used to evaluate WTW greenhouse gas (GHG) emissions and fossil fuel consumption of waste-derived fuels. Two waste-to-energy (WTE) pathways have been evaluated – one for compressed natural gas (CNG) production using food waste via anaerobic digestion, and the other for ethanol production from yard trimmings via fermentation processes. Because the fuel production pathways displace current waste management practices (i.e., landfilling waste), we use a marginal approach that considers only the differences in emissions between the counterfactual case and the alternative fuel production case. The results show that the renewable CNG from food waste can reduce GHG emissions by 28–157% compared with CNG from fossil sources, while the ethanol from yard trimmings waste can reduce GHG emissions by 52–146% compared with gasoline. Most of the reduction results from avoiding the emissions associated with the counterfactual scenario, mainly uncontrolled CH4 emissions from landfills. Because waste-derived fuels are non-fossil fuels, WTW fossil fuel consumption is also reduced dramatically: by 106% for the CNG produced from food waste compared with that of natural gas, and 74% for ethanol produced from yard trimmings compared with that of gasoline. However, the results depend on the conditions of both the counterfactual scenarios and the alternative fuel production scenarios. In order to refine the results, further investigation is needed for the parameters of landfill gas (LFG) emissions, which are subject to many uncertainties.
An assessment of the potential products and economic and environmental impacts resulting from a billion ton bioeconomy
J. Rogers, B. Stokes, J. Dunn, H. Cai, M. Wu, Z. Haq, H. Baumes
http://onlinelibrary.wiley.com/doi/10.1002/bbb.1728/full
http://greet.es.anl.gov/publication-bton_bioeconomy
This paper is the summation of several analyses to assess the size and benefits of a Billion Ton Bioeconomy, a vision to enable a sustainable market for producing and converting a billion tons of US biomass to bio-based energy, fuels, and products by 2030. Two alternative biomass availability scenarios in 2030, defined as the (i) Business-as-usual (598 million dry tons) and (ii) Billion Ton (1042 million dry tons), establish a range of possible outcomes for the future bioeconomy. The biomass utilized in the current (2014) (365 million dry tons) economy is estimated to displace approximately 2.4% of fossil energy consumption and avoid 116 million tons of CO2-equivalent (CO2e) emissions, whereas the Billion Ton bioeconomy of 2030 could displace 9.5% of fossil energy consumption and avoid as much as 446 million tons of CO2 equivalent emissions annually. Developing the integrated systems, supply chains, and infrastructure to efficiently grow, harvest, transport, and convert large quantities of biomass in a sustainable way could support the transition to a low-carbon economy. Bio-based activities in the current (2014) economy are estimated to have directly generated more than $48 billion in revenue and 285 000 jobs. Our estimates show that developing biomass resources and addressing current limitations to achieve a Billion Ton bioeconomy could expand direct bioeconomy revenue by a factor of 5 to contribute nearly $259 billion and 1.1 million jobs to the US economy by 2030. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd
The influence of the catalysts on Biofuel life cycle analysis (LCA)
P. T. Benavides, D. C. Cronauer, F. Adom, Z. Wang, J. B. Dunn
http://dx.doi.org/10.1016/j.susmat.2017.01.002
http://greet.es.anl.gov/publication-cata_biofuel_lca
Catalysts play an important role in biofuel production but are rarely included in biofuel life cycle analysis (LCA). In this work, we estimate the cradle-to-gate energy consumption and greenhouse gas (GHG) emissions of Pt/γ-Al2O3, CoMo/γ-Al2O3, and ZSM-5, catalysts that could be used in processes to convert biomass to biofuels. We also consider the potential impacts of catalyst recovery and recycling. Integrating the energy and environmental impacts of CoMo/γ-Al2O3 and ZSM-5 into an LCA of renewable gasoline produced via in-situ and ex-situ fast pyrolysis of a blendedwoody feedstock revealed that the ZSM-5,with cradle-to-gate GHG emissions of 7.7 kg CO2e/kg, could influence net life-cycle GHG emissions of the renewable gasoline (1.7 gCO2e/MJ for the in-situ process, 1.2 gCO2e/MJ for the ex-situ process) by up to 14% depending on the loading rate. CoMo/γ-Al2O3 had a greater GHG intensity (9.6 kg CO2e/kg) than ZSM-5, however, it contributed approximately only 1% to the life-cycle GHG emissions of the renewable gasoline because of the small amount of this catalyst needed per kg of biofuel produced. Given that catalysts can contribute significantly to biofuel life-cycle GHG emissions depending on the GHG intensity of their production and their consumption rates, biofuel LCAs should consider the potential influence of catalysts on LCA results.
Supply Chain Sustainability Analysis of Renewable Hydrocarbon Fuels via Indirect Liquefaction, Fast Pyrolysis, and Hydrothermal Liquefaction: Update of the 2016 State-of-Technology Cases and Design Cases
H. Cai, J. Dunn, A. Pegallapati, Q. Li, C. Canter, E. Tan, M. Biddy, R. Davis, J. Markham, M. Talmadge, D. Hartley, D. N. Thompson, P. A. Meyer, Y. Zhu, L. Snowden-Swan, S. Jones
http://greet.es.anl.gov/publication-renewable_hc_2016_update
Life-cycle analysis of fuels from post-use non-recycled plastics
P. T. Benavides, P. Sun, J. Han, J. B. Dunn, M. Wang
http://dx.doi.org/10.1016/j.fuel.2017.04.070
http://greet.es.anl.gov/publication-post_nonrecy_plast_lca
Plastic-to-fuel (PTF) technology uses pyrolysis to convert plastic waste—especially non-recycled plastics (NRP)—into ultra-low sulfur diesel (ULSD) fuel. To assess the potential energy and environmental benefits associated with PTF technology, we calculated the energy, water consumption, and greenhouse gas emissions of NRP-derived ULSD and compared the results to those metrics for conventional ULSD fuel. For these analyses, we used the Greenhouse gases, Regulated Emissions and Energy use in Transportation (GREET) model. Five companies provided pyrolysis process product yields and material and energy consumption data. Co-products of the process included char and fuel gas. Char can be landfilled, which, per the company responses, is the most common practice for this co-product, or it may be sold as an energy product. Fuel gas can be combusted to internally generate process heat and electricity. Sensitivity analyses investigated the influence of co-product handling methodology, product yield, electric grid composition, and assumed efficiency of char combustion technology on life-cycle greenhouse gas emissions. The sensitivity analysis indicates that the GHG emissions would likely be reduced up to 14% when it is compared to conventional ULSD, depending on the co-product treatment method used. NRP-derived ULSD fuel could therefore be considered at a minimum carbon neutral with the potential to offer a modest GHG reduction. Furthermore, this waste-derived fuel had 58% lower water consumption and up to 96% lower fossil fuel consumption than conventional ULSD fuel in the base case. In addition to the comparison of PTF fuels with conventional transportation fuels, we also compare the results with alternative scenarios for managing NRP including power generation and landfilling in the United States.
Regional water consumption for hydro and thermal electricity generation in the United States
U. Lee, J. Han, A. Elgowainy, M. Wang
http://greet.es.anl.gov/publication-regional_water_in_power_sector
Water is an essential resource for most electric power generation technologies. Thermal power plants typically require a large amount of cooling water whose evaporation is regarded to be consumed. Hydropower plants result in evaporative water loss from the large surface areas of the storing reservoirs. This study estimated the regional water consumption factors (WCFs) for thermal and hydro electricity generation in the United States, because the WCFs of these power plants vary by region and water supply and demand balance are of concern in many regions. For hydropower, total WCFs were calculated using a reservoir's surface area, state-level water evaporation, and background evapotranspiration. Then, for a multipurpose reservoir, a fraction of its WCF was allocated to hydropower generation based on the share of the economic valuation of hydroelectricity among benefits from all purposes of the reservoir. For thermal power plants, the variations in WCFs by type of cooling technology, prime mover technology, and by region were addressed. The results show that WCFs for electricity generation vary significantly by region. The generation-weighted average WCFs of thermoelectricity and hydropower are 1.25 (range of 0.18–2.0) and 16.8 (range of 0.67–1194) L/kWh, respectively, and the generation-weighted average WCF by the U.S. generation mix in 2015 is estimated at 2.18 L/kWh.
Cellulosic ethanol: status and innovation
L. Lynd, X. Liang, M. Biddy, A. Allee, H. Cai, T. Foust, M. Himmel, M. Laser, M. Wang, C. Wyman
http://greet.es.anl.gov/publication-cellulosic_etoh
Although the purchase price of cellulosic feedstocks is competitive with petroleum on an energy basis, the cost of lignocellulose conversion to ethanol using today's technology is high. Cost reductions can be pursued via either in-paradigm or new-paradigm innovation. As an example of new-paradigm innovation, consolidated bioprocessing using thermophilic bacteria combined with milling during fermentation (cotreatment) is analyzed. Acknowledging the nascent state of this approach, our analysis indicates potential for radically improved cost competitiveness and feasibility at smaller scale compared to current technology, arising from (a) R&D-driven advances (consolidated bioprocessing with cotreatment in lieu of thermochemical pretreatment and added fungal cellulase), and (b) configurational changes (fuel pellet coproduction instead of electricity, gas boiler(s) in lieu of a solid fuel boiler).
Greenhouse Gas Emissions, Energy and Water Use of Photobioreactors for Algal Cultivation and Biofuels Production
Q. Li, C. Canter
http://greet.es.anl.gov/publication-algal_cultivation_biofuel
The Department of Energy's Bioenergy Technology Office (BETO) collaborates with a wide range of institutions towards the development and deployment of biofuels and bioproducts (DOE BETO 2016). To facilitate this effort, BETO and its partner national laboratories develop detailed techno-economic assessments (TEA) of biofuel production technologies. The National Renewable Energy Laboratory (NREL) recently completed an algal cultivation photobioreactor (PBR) study as part of an internal BETO milestone (Davis et al., 2017, the PBR study henceforth), which used a techno-economic analysis (TEA) to estimate the minimum biomass-selling price (MBSP) of algae biomass at the farm gate. The biomass cost projections considered the design and operation of a culture inoculum system, biomass production, CO2 storage and delivery, onsite circulation of cultures and clarified water, makeup water delivery, and biomass dewatering. The goal of this analysis is to expand the GREET model and determine greenhouse gas (GHG) emissions, fossil energy consumption, and water use from the algal biomass production and dewatering operations as modeled in the PBR study. To obtain the well-to-wheel (WTW) life-cycle GHG emissions, energy and water use from PBR study (biomass production and dewatering) were added to the combined algae process (CAP). CAP produces renewable diesel and naphtha from lipids, ethanol from sugars, and heat-power-nutrient recycles from anaerobic digestion of the protein residue (Frank et al. 2016).
Wells to wheels: Environmental implications of natural gas as a transportation fuel
H. Cai, A. Burnham, R. Chen, M. Wang
http://greet.es.anl.gov/publication-wtw_ng_trans
We assessed freshwater consumption, greenhouse gas (GHG) emissions, and air emissions of using compressed and liquefied natural gas (NG) as transportation fuels by three heavy-duty NG vehicles (NGV) types from a wells-to-wheels (WTW) perspective. We analyzed freshwater consumption for NG production in major U.S. shale gas plays from recent reports and studies. We reviewed recent literature quantifying methane leakage from the NG supply chain and vehicle use to improve the estimates of NGV GHG emissions. Results show that NGVs could reduce freshwater consumption significantly and offer air emissions reduction benefits compared to their diesel counterparts. NGV WTW GHG emissions are largely driven by the vehicle fuel efficiency, as well as methane leakage rates of both the NG supply chain and vehicle end use: we estimate WTW GHG emissions of NGVs to be slightly higher than those of the diesel counterparts given the estimated WTW methane leakage. NGVs utilizing the newest aftertreatment systems have lower WTW and vehicle operation NOx emissions across different duty-cycles and slightly lower WTW PM emissions than their diesel counterparts. We found that the cost-effectiveness of NGVs is impacted by incremental cost of NG storage tanks and the price difference between NG and diesel fuels. These findings for NGVs shed light on their environmental and economic impacts from a WTW holistic point of view.
Evaluation of landfill gas emissions from municipal solid waste landfills for the life-cycle analysis of waste-to-energy pathways
http://greet.es.anl.gov/publication-msw_to_energy_emis
Various waste-to-energy (WTE) conversion technologies can generate energy products from municipal solid waste (MSW). Accurately evaluating landfill gas (LFG, mainly methane) emissions from base case landfills is critical to conducting a WTE life-cycle analysis (LCA) of their greenhouse gas (GHG) emissions. To reduce uncertainties in estimating LFG, this study investigated key parameters for its generation, based on updated experimental results. These results showed that the updated parameters changed the calculated GHG emissions from landfills significantly depending on waste stream; they resulted in a 65% reduction for wood (from 2412 to 848 t CO2e/dry t) to a 4% increase for food waste (from 2603 to 2708 t CO2e/dry t). Landfill GHG emissions also vary significantly based on LFG management practices and climate. In LCAs of WTE conversion, generating electricity from LFG helps reduce GHG emissions indirectly by displacing regional electricity. When both active LFG collection and power generation are considered, GHG emissions are 44% less for food waste (from 2708 to 1524 t CO2e/dry t), relative to conventional MSW landfilling. The method developed and data collected in this study can help improve the assessment of GHG impacts from landfills, which supports transparent decision-making regarding the sustainable treatment, management, and utilization of MSW.
AFLEET Tool - Version History 2017
http://greet.es.anl.gov/publication-afleet-revision-history-2017
Update of Process Energy Requirement and Material Efficiency for Steel and Al Stamping in the GREET Model
Q. Dai, J. C. Kelly, A. Elgowainy
http://greet.es.anl.gov/publication-steel_al_update_2017
This memo documents the changes in the energy requirement and material efficiency for stamping of steel and aluminum in the GREET model. These changes reflect the current status of stamping processes associated with vehicle production, and will be incorporated into GREET 2017.
Update of Life Cycle Analysis of Lithium-ion Batteries in the GREET Model
Q. Dai, J. Dunn, J. Kelly, A. Elgowainy
http://greet.es.anl.gov/publication-Li_battery_update_2017
This memo documents updates for life cycle analysis of lithium-ion batteries (LIB) in the GREET model. These updates were obtained through 1) our site visits to two LIB manufacturing facilities and one LIB recycling facility in China; 2) Argonne's latest modeling effort by Ahmed et al to support efficient simulation, analysis, and design of advanced LIB technologies. These updates therefore reflect the current status of lithium nickel manganese cobalt oxide (NMC) cathode material production and LIB manufacturing, and will be incorporated into GREET 2017.
Update of Vehicle Weights in the GREET® Model
J. Kelly, J. Han, Q. Dai, A. Elgowainy
http://greet.es.anl.gov/publication-v_weight_update_2017
This memo documents changes to the weight of vehicles (passenger cars, sport utility vehicles and pickup trucks) within GREET2 2016. These changes reflect the current status of vehicle weight, and will be incorporated into GREET 2017.
Analytical Models of Carbon Capture Plant Configurations in GREET
S. Supekar, J. Kelly, A. Elgowainy
http://greet.es.anl.gov/publication-ele_ccs_2017
Addition of Combined Heat and Power Electricity Plants to the GREET® Model
J. Kelly, A. Elgowainy
http://greet.es.anl.gov/publication-chp_add_2017
This document describes additions of several combined heat and power (CHP) electrical generating plants to the GREET® (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model. The GREET model was originally developed to evaluate fuel-cycle (or well-to-wheels) energy use and emissions of various transportation technologies (Wang 1999). Numerous electricity generating technology and fuel pathways exist within GREET and this update describes how CHP data was obtained and integrated within 2017 GREET.
Update on Generation Efficiency and Criteria Air Pollutant Emissions of Integrated Coal Gasification Combined Cycle Power Plant
H. Cai, J. Kelly, M. Wang
http://greet.es.anl.gov/publication-coal_igcc_2017
This memo documents updates for the generation efficiency and criteria air pollutant (CAP) emission factors of integrated coal gasification combined cycle (IGCC) power plant used in the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET®) model.
Updates on the Energy Consumption of the Beef Tallow Rendering Process and the Ratio of Synthetic Fertilizer Nitrogen Supplementing Removed Crop Residue Nitrogen in GREET
R. Chen, Z. Qin, C. Canter, H. Cai, J. Han, M. Wang
http://greet.es.anl.gov/publication-beef_tallow_update_2017
This memo documents Argonne's update on the energy inputs regarding beef tallow rendering process in GREET 2016 model.
Updated Natural Gas Pathways in the GREET1_2017 Model
http://greet.es.anl.gov/publication-ng_update_2017
Argonne National Laboratory researchers have been analyzing the environmental impacts of natural gas (NG) production and use for more than 15 years. With the rapid development of shale gas production in the past few years, significant efforts have been made to examine various stages of natural gas pathways to estimate their life-cycle impacts. In 2011, Argonne researchers examined the uncertainty associated with key parameters for shale gas and conventional NG pathways to identify data gaps that required further attention (Clark et al. 2011). Clark et al. (2011) based much of their analysis of methane (CH4) emissions on the United States Environmental Protection Agency's (EPA's) 2011 greenhouse gas inventory (GHGI), as this was the first EPA GHGI to incorporate shale gas and included significant revisions to its liquid unloading leakage estimates (EPA 2011). In addition, the report examined the water, materials, and fuel needed to drill and construct NG wells. From 2013 to 2016, Argonne researchers updated the GREET model based on EPA's latest GHG inventories, which included several methodological changes for estimating natural gas CH4 emissions (Burnham et al. 2013; Burnham et al. 2014; Burnham et al. 2015; Burnham et al. 2016). In 2015, Argonne analyzed the environmental impacts, including CH4 leakage and air pollutant emissions, of heavy-duty natural gas vehicles (Cai et al. 2015). Natural gas pathways in GREET1_2017 have been updated based on the work documented in Cai et al. (2017), which examined upstream freshwater consumption, greenhouse gas (GHG) emissions, and natural gas vehicle nitrogen oxides (NOx) and particulate matter (PM) emissions. The results documented in Cai et al. (2017) needed to be supplemented in order to finalize the GREET update. The following sections briefly summarize the supplemental information used to update the model.
Creation of unit process data for life cycle assessment of steam methane reforming and petroleum refining
B. Young, B. Morelli, T. Hawkins
http://greet.es.anl.gov/publication-air_pollutants_smr_petroleum
This study provides detailed, baseline gate-to-gate unit process data for petroleum refining and hydrogen production. The datasets improve the resolution of the environmental releases attributable to specific processes involved in petroleum refining and steam methane reforming (SMR) and the attribution of releases to the products of refineries. These datasets are intended for use in life cycle assessment studies and will be implemented in the GREET software tool. These data are important for understanding the impacts of products and transportation options that use pure hydrogen and the products derived from refined petroleum. It also provides detail to allow resource use and environmental releases to be attributed in a more defensible manner to refinery products and hydrogen produced by SMR. A distinguishing feature of the approach proposed here is the creation of estimates based on a comprehensive inventory of emissions reported by facilities including subprocess detail. The activity factors provided here allow for the calculation of emissions and resource use associated with individual processes within the steam methane reforming facility and the petroleum refinery, and the use of reported data inclusive of all processes within the refinery provides coverage of all relevant aspects. This approach allows for validation of results by providing comprehensiveness, sub-facility level detail, and proper attribution of releases and resource use to products. The insights and datasets created in this project are useful for considering modifications to the processes used to produce hydrogen and petroleum derived products and for characterizing a wide variety of product and transportation systems.
M. Wang, A. Elgowainy, J. Han, P. Benavides, A. Burnham, H. Cai, C. Canter, R. Chen, Q. Dai, J. Kelly, D. Lee, U. Lee, Q. Li, Z. Lu, Z. Qin, P. Sun, S. Supekar
http://greet.es.anl.gov/publication-greet-2017-summary
This report provides a technical summary of the expansions and updates to the 2017 release of Argonne National Laboratory's Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET®) model, including references and links to key technical documents related to these expansions and updates. The GREET 2017 release includes an updated version of the GREET1 (the fuel-cycle GREET model) and GREET2 (the vehicle-cycle GREET model), both in the Microsoft Excel platform and in the GREET.net modeling platform.
Refinery Modeling for Argonne National Laboratory
J. Jenkins, V. DiVita
http://greet.es.anl.gov/publication-refinery_anl
With support of the U.S. Department of Energy, Argonne National Laboratory is conducting a comprehensive well-to-wheels (WTW) analysis for the Fuels Working Group (FWG) of US DRIVE — a partnership between the US government and auto and energy industries — to examine energy and GHG effects of producing fuels with higher octane ratings produced with various gasoline blending stocks and renewable blending components for use in vehicle engines developed for the new fuel properties. Understanding changes to petroleum refining activities to produce such fuels is key to this WTW analysis. Linear programming (LP) modeling is an appropriate technique for simulating these activities. Jacobs Consultancy was retained to design and conduct various LP modeling cases with its proprietary LP model.
Life cycle energy and greenhouse gas emission effects of biodiesel in the United States with induced land use change impacts
R. Chen, Z. Qin, J. Han, M. Wang, F. Taheripour, W. Tyner, D. O'Connor, J. Duffield
http://www.sciencedirect.com/science/article/pii/S0960852417321648?via%3Dihub
http://greet.es.anl.gov/publication-lc_biodiesel_us_w_luc
This study conducted the updated simulations to depict a life cycle analysis (LCA) of the biodiesel production from soybeans and other feedstocks in the U.S. It addressed in details the interaction between LCA and induced land use change (ILUC) for biodiesel. Relative to the conventional petroleum diesel, soy biodiesel could achieve 76% reduction in GHG emissions without considering ILUC, or 66–72% reduction in overall GHG emissions when various ILUC cases were considered. Soy biodiesel's fossil fuel consumption rate was also 80% lower than its petroleum counterpart. Furthermore, this study examined the cause and the implication of each key parameter affecting biodiesel LCA results using a sensitivity analysis, which identified the hot spots for fossil fuel consumption and GHG emissions of biodiesel so that future efforts can be made accordingly. Finally, biodiesel produced from other feedstocks (canola oil and tallow) were also investigated to contrast with soy biodiesel and petroleum diesel.
Carbon Calculator for Land Use Change from Biofuels Production (CCLUB) Manual (Rev. 4)
J. Dunn, Z. Qin, S. Mueller, H-Y. Kwon, M. Wander, M. Wang
May 30, 2012 revised on: December 19, 2017
http://greet.es.anl.gov/publication-cclub-manual-r4
This document is an update to a previous version of this report with number ANL/ESD/12-5 Rev.3.
Life Cycle Greenhouse Gas Emissions of By-product Hydrogen from Chlor-Alkali Plants
D.-Y. Lee, A. Elgowainy, Q. Dai
http://greet.es.anl.gov/publication-chlor_alkali_h2
Land management change greatly impacts biofuels' greenhouse gas emissions
Z. Qin, C. Canter, J. Dunn, S. Mueller, H. Kwon, J. Han, M. Wander, M. Wang
http://onlinelibrary.wiley.com/doi/10.1111/gcbb.12500/full
http://greet.es.anl.gov/publication-land_management_biofuels
Harvesting corn stover for biofuel production may decrease soil organic carbon (SOC) and increase greenhouse gas (GHG) emissions. Adding additional organic matter into soil or reducing tillage intensity, however, could potentially offset this SOC loss. Here, by using SOC and life cycle analysis (LCA) models, we evaluated the impacts of land management change (LMC), i.e., stover removal, organic matter addition, and tillage on spatially explicit SOC level and biofuels' overall life-cycle GHG emissions in U.S. corn-soybean production systems. Results indicate that under conventional tillage (CT), 30% stover removal (dry weight) may reduce SOC by 0.04 t C ha−1yr−1 over a 30-year simulation period. Growing a cover crop during the fallow season or applying manure, on the other hand, could add to SOC and further reduce biofuels' life-cycle GHG emissions. With 30% stover removal in a CT system, cover crop and manure application can increase SOC at the national level by about 0.06 and 0.02 t C ha−1yr−1, respectively, compared to cases without such measures. With contributions from this SOC increase, the life-cycle GHG emissions for stover ethanol are more than 80% lower than those of gasoline, exceeding the U.S. Renewable Fuel Standard mandate of 60% emissions reduction for cellulosic biofuels. Reducing tillage intensity while removing stover could also limit SOC loss or lead to SOC gain, which would lower stover ethanol life-cycle GHG emissions to near or under the mandated 60% reduction. Without these organic matter inputs or reduced tillage intensity, however, the emissions will not meet this mandate. More efforts are still required to further identify key practical LMCs, improve SOC modeling, and accounting for LMCs in biofuel LCAs that incorporate stover removal.
Carbon dynamics for biofuels produced from woody feedstocks
J. Han, C. Canter, H. Cai, M. Wang, Z. Qin, J. Dunn
http://greet.es.anl.gov/publication-woody_lca
Growing biomass incorporates atmospheric carbon and stores it as biogenic carbon. In a biorefinery, some portion of this biogenic carbon is converted into a biofuel, which then emits biogenic CO2 through the biofuel combustion. In the Life Cycle Analysis (LCA) of biofuels, it is generally assumed that this biogenic CO2 emission is offset by atmospheric carbon uptake during biomass growth, establishing the so-called carbon neutrality of biogenic carbon. When the elapsed time between biomass growth and biofuel combustion is short, this assumption is defensible. In the case of slower-growing forestry-derived bioenergy feedstocks, however, this time window may be significantly longer and the assumption of carbon neutrality is weaker. To address the carbon neutrality issue of woody-biomass-derived biofuels, this study investigated the carbon dynamics of producing bioenergy from woody biomass. Specifically, key factors affecting the net GHG emissions results, such as biomass species, land analysis framework, and the sequencing of the planting and harvest steps, were examined. This study examined two different types of analysis frameworks: stand-level and landscape-level analyses. A stand-level analysis examines the impacts of temporal carbon dynamics of carbon emissions/sequestration over time, which is a critical issue in LCAs of woody biomass products. The stand-level analysis is based on a narrowly defined biomass growth scenario and harvest geographic boundary. The specific growth scenario may have high variability, especially with long growth cycles. A landscape-level analysis, on the other hand, is appropriate for conducting LCAs of products from managed forest assuming sustainable forestry management, e.g., the overall carbon fluxes associated with forest growth and harvest/mortality are balanced. A landscape-level analysis can represent managed (or private) forests that are intended to provide a constant supply of biomass to their customers, including bioenergy plant operators. This study included two general types of forest biomass: managed softwoods, represented by Douglas fir, loblolly pine, and spruce/fir mixtures, and dedicated short-rotation woody crops (SRWCs), represented by poplar, willow and eucalyptus. The softwoods were selected to represent the dominant wood species found in the Pacific Northwest (Douglas fir), the southern United States (loblolly pine), and the northeastern U.S. (spruce/fir). The SRWCs were selected to represent systems that have been commercially deployed in the Pacific Northwest (poplar), the southern U.S. (eucalyptus), and the northeastern U.S. (willow). The sequencing of the planting and harvest, and biogenic carbon release steps, also had a major impact on the carbon accounting. One analysis framework (Cycle 1) starts with 1) the "harvest" of standing trees, followed by 2) the production and use of the biofuels, and 3) replanting, and recapture of the released carbon. An alternative framework (Cycle 2) starts with 1) the planting of the wood and the capture of atmospheric carbon, followed by 2) harvesting of the trees, and 3) release of the biogenic carbon in the production and use of the biofuel. With Cycle 1, the carbon emissions released from biofuel production and combustion are allocated before biomass growth and harvest, and handled accordingly by the CO2 emission-discounting method; the slow growth of softwoods (especially Douglas fir and spruce/fir) results in a large portion of the upfront carbon debt being recovered slowly. With discounting, the carbon uptake during biomass regrowth becomes less significant. Cycle 2 is appropriate for SRWCs because these will be established dedicatedly for bioenergy or bioproducts production, which starts with the silviculture, and Cycle 1 is more appropriate for softwoods because it is more realistic to collect the thinnings and residues when they are readily available for bioenergy production than to wait for decades to grow a mature softwood stand when the thinnings and residues could be made available. Using both stand- and landscape-level analyses, this work shows that biofuels derived from woody biomass with longer growth cycles and slower growth rates, e.g., Douglas fir and spruce/fir, have much larger variations in GHG emissions depending on the land analysis framework and CO2 emission cycle compared to biofuels derived from woody biomass with shorter growth cycles and faster growth rate, e.g., SRWCs. For example, the GHG emissions associated with renewable gasoline from eucalyptus, poplar, and willow range from 40 to 47, 37 to 41, and 45 to 50 g CO2e/MJ, respectively, depending on the analysis cycles, in comparison to 94 g CO2e/MJ for petroleum gasoline. On the other hand, the renewable gasoline from loblolly pine, Douglas fir, and spruce/fir generate GHG emissions ranging from 19 to 42, 13 to 67, and -10 to 56 g CO2e/MJ, respectively, depending on the analysis cycles. Thus, much caution is needed to handle the temporal carbon dynamics issue for biofuels from woody biomass with long growth cycles and slow growth rates.
Techno-economic analysis and life-cycle analysis of two light-duty bioblendstocks: isobutanol and aromatic-rich hydrocarbons
H. Cai, J. Markham, S. Jones, P. Benavides, J. Dunn, M. Biddy, L. Tao, P. Lamers, S. Phillips
https://pubs.acs.org/doi/abs/10.1021/acssuschemeng.8b01152
http://greet.es.anl.gov/publication-two_ld_bios
Isobutanol and aromatic-rich hydrocarbons (ARHC) are two biomass-derived high-octane blendstocks that could be blended with petroleum gasoline for use in optimized spark-ignition engines in light-duty vehicles, potentially increasing engine efficiency. To evaluate technology readiness, economic viability, and environmental impacts of these technologies, we use detailed techno-economic analysis (TEA) and life-cycle analysis (LCA). We assumed isobutanol is produced via biochemical conversion of an herbaceous feedstock blend while ARHC is produced via thermochemical conversion of a woody feedstock blend. The minimum estimated fuel selling price (MFSP) of isobutanol ranged from $5.57/gasoline gallon equivalent (GGE) ($0.045/MJ) based on today's technology to $4.22/GGE ($0.034/MJ) with technology advancements. The MFSP of ARHC could decline from $5.20/GGE ($0.042/MJ) based on today's technology to $4.20/GGE ($0.034/MJ) as technology improves. Both isobutanol and ARHC offer about 73% greenhouse gas (GHG) emission reduction relative to petroleum gasoline per LCA of these two bioblendstocks. On the other hand, water consumption in the production of both bioblendstocks exceeds that of conventional gasoline although process engineering offers routes to cutting water consumption. Over their life-cycles, both isobutanol and ARHC emit more NOx and PM2.5 than petroleum gasoline. Improving the energy efficiency and lowering air emissions from agricultural equipment will reduce the life-cycle air pollutant emissions of these bioblendstocks.
Incentivizing adoption of plug-in electric vehicles: A review of global policies and markets
T. Stephens, Y. Zhou, A. Bumham, M. Wang
http://greet.es.anl.gov/publication-incentivizing_pev
This report summarizes current government policies that seek to increase deployment of light-duty, plug-in electric vehicles (PEVs) in the United States, Europe, and China. The paper also describes recent PEV market trends in these three regions. By comparing combinations of PEV policies and trends of PEV sales in different regions at national and subnational levels, the authors make several observations and draw general conclusions, using supporting examples for the findings. One finding, consistent with earlier studies, is that multiple, complementary PEV incentives and deployment policies are generally more effective in increasing adoption of PEVs within a given market than single policies. In most regions, financial incentives, especially pointof- sale incentives, are effective in increasing adoption, particularly when generous and combined with other supporting polices, such as increasing charging station availability, which contributes to ease of use. The authors also observed differences in policies and market trends between regions. In Europe, where taxes on vehicles are high, tax credits provide strong incentives for PEV adoption, whereas in several Chinese cities, where restrictions on vehicle registration or use are imposed, relaxation of restrictions on PEVs effectively promote PEV adoption. In addition, governments are replacing some policies based on technical specifications (e.g., battery capacity) with policies based on performance metrics (e.g., vehicle range and electricity consumption rate per distance).
Life‐cycle analysis of integrated biorefineries with co‐production of biofuels and bio‐based chemicals: co‐product handling methods and implications
H. Cai, J. Han, M. Wang, R. Davis, M. Biddy, E. Tan
https://onlinelibrary.wiley.com/doi/abs/10.1002/bbb.1893
http://greet.es.anl.gov/publication-biorefinery_coproduct_method
New integrated biorefinery (IBR) concepts are being investigated to co‐produce hydrocarbon fuels and high‐value bio‐based chemicals to improve the economic viability of IBRs, to enhance biomass resource utilization efficiencies, and to maximize potential greenhouse gas (GHG) emission reductions. Unlike fuel‐only biorefineries, IBRs may co‐produce a significant amount of bio‐based chemicals, whose emission implications for specific biorefinery products and the biorefinery as a whole need to be evaluated. We discuss this in principle and apply three sets of co‐product handling methods to conduct life‐cycle analysis (LCA) of modeled IBRs with co‐production of two bioproduct examples – succinic acid and adipic acid – alongside a renewable diesel blendstock fuel product. The LCA results for the specific co‐product handling methods that were examined shed light on potential artifacts of product‐specific LCA with selected co‐product methods. We discuss the advantages and limitations of each method and conclude that (i) a system‐level or 'black‐box' LCA allocation method is too simplistic to reflect appropriately the GHG burdens of distinctly different processing trains for fuels and chemicals in the IBR context, and (ii) the displacement method is the only co‐product handling method that accounts fully for the emission effects of both the fuel product and the non‐fuel bio‐based co‐products in the IBRs within the context of the existing fuel‐focused GHG regulatory framework. Alternatively, biorefinery system‐level LCA combines benefits of individual products to offer a complete picture. This system‐level LCA approach offers a holistic LCA without somewhat arbitrary decisions either on an allocation basis or by the selection of an evaluation metric based on specific products.
Exploring Comparative Energy and Environmental Benefits of Virgin, Recycled, and Bio-Derived PET Bottles
P. Benavides, J. Dunn, J. Han, M. Biddy, J. Markham
https://pubs.acs.org/doi/10.1021/acssuschemeng.8b00750
http://greet.es.anl.gov/publication-pet_bottles
Polyethylene terephthalate (PET) is a common plastic resin used to produce packaging, notably plastic bottles. Most PET bottles are produced from fossil fuel-derived feedstocks. Bio-derived and recycling-based pathways to PET bottles, however, could offer lower greenhouse gas (GHG) emissions than the conventional route. In this paper, we use life-cycle analysis to evaluate the GHG emissions, fossil fuel consumption, and water consumption of producing one PET bottle from virgin fossil resources, recycled plastic, and biomass, considering each supply chain stage. We considered two routes to produce bottles from biomass: one in which all PET precursors (ethylene glycol and teraphthalic acid) are bio-derived and one in which only ethylene glycol is bio-derived. Bio-derived and recycled PET bottles offer both GHG emissions and fossil fuel consumption reductions ranging from 12% to 82% and 13% to 56%, respectively, on a cradle-to-grave basis compared to fossil fuel-derived PET bottles assuming PET bottles are landfilled. However, water consumption is lower in the conventional pathway to PET bottles. Water demand is high during feedstock production and conversion in the case of biomass-derived PET and during recycling in the case of bottles made from recycled PET.
2017 Algae Harmonization Study: Evaluating the Potential for Future Algal Biofuel Costs, Sustainability, and Resource Assessment from Harmonized Modeling
R. Davis, A. Coleman, M. Wigmosta, J. Markham, C. Kinchin, Y. Zhu, S. Jones, J. Han, C. Canter, Q. Li
http://greet.es.anl.gov/publication-2017_alage_harmonization
To present a more unified picture of the long-term future potential for algal biofuels and the goals that must be met to reach that potential, four national laboratory algae modeling groups collaborated to harmonize respective models for resource assessment, techno-economic analysis, and life-cycle analysis of algal biomass production and conversion processes. In contrast to prior harmonization studies that this group has previously conducted, which focused on establishing benchmarks attributed to current performance at the time, the primary intent of the present harmonization study was to project these models to forward-looking targets that must be achieved to improve economic and environmental sustainability metrics towards more viable levels in the future, within limitations for location availabilities identified by resource assessment modeling and thus national-scale fuel output potential (i.e., billion gallons gasoline equivalent per year, BGGE/yr).
Estimating emissions related to indirect peatland loss in Southeast Asia due to biofuel production
Z. Qin, H. Kwon
http://greet.es.anl.gov/publication-iluc_peat
ILUC stands for indirect land use change or induced land use change, which is normally accounted for its impact on biofuels' greenhouse gas (GHG) emissions (Chen et al., 2018). Due to its complexity, the ILUC emissions are estimated using models involving area changes of specific land types and emission factors (EFs) for conversion of one land type to another. Without diving into too many details, one can identify two major "ILUC factors" determining the ILUC emissions, the ΔILUC which reflects the area of land that transits from one type of land use to another, and the EFs that determine specific (i.e., CO2, N2O and CH4) or total emissions (in terms of total GHG) per unit area changed associated with specific ILUC. It is critical to include both factors in ILUC emissions estimation. Here we show recent updates that are specifically related to ΔILUC and EFs for one of the ILUCs contributed to biofuels' ILUC emissions, the forest-on-peat to palm transition in Southeast Asia (mainly Indonesia and Malaysia). Further, we incorporate such updates into the CCLUB module (aka. Carbon Calculator for Land Use change from Biofuels production) that used in the GREET® model to estimate ILUC impacts, and briefly discuss ILUC emissions associated with soy biodiesel production in the U.S.
AWARE-US: Quantifying water stress impacts of energy systems in the United States
U. Lee, H. Xu, J. Daystar, A. Elgowainy, M. Wang
http://greet.es.anl.gov/publication-aware_us
Energy production typically consumes a large amount of fresh water, which is a critical resource for both human and ecosystem needs. Robust water impact analysis is prudent prior to deploying new energy systems at scale. While there are many water indices representing relative water availability (or scarcity), they are not suitable for analyzing the impact of consumptive water in the context of life-cycle analysis (LCA). The available water remaining (AWARE) concept, developed by the Water Use in LCA Group, enables global water impact analysis (AWARE-Global). However, while AWARE-Global enables consistent comparison internationally, it lacks the high spatial resolution and fidelity needed for decision-making at the local level regarding energy system deployment within the United States (U.S.). In this study, we developed an AWARE system for applications in the contiguous U.S. (AWARE-US) by incorporating measured runoff and human water use data at U.S. county-level resolution. Results of AWARE-US quantify the water stress and the impacts of increase in water consumption in various regions within the U.S. To demonstrate the potential use of AWARE-US, we evaluated the impacts of a potential hydrogen fuel cell electric vehicle deployment scenario on the regional water stress in various regions within the U.S.
Updating Transmission and Distribution Losses in the GREET® Model
http://greet.es.anl.gov/publication-Update_td_losses_2018
This memo documents an update of the transmission and distribution loss factor for electricity in the GREET model. Based on recent data, a new transmission and distribution loss factor will be incorporated into GREET 2018 for the United States. The updated data builds upon methods used by Cai et al. (2012), the Energy Information Administration (EIA) (2018) and the Environmental Protection Agency (EPA) (2018). Details regarding data, methods, and technical considerations are provided.
Z. Qin, H. Kwon, J. Dunn, S. Mueller, M. Wander, M. Wang
The Carbon Calculator for Land Use Change from Biofuels Production (CCLUB) model calculates greenhouse gas (GHG) emissions from land use change (LUC) for four different ethanol production pathways including corn grain ethanol and cellulosic ethanol from corn stover, Miscanthus, and switchgrass, and a soy biodiesel pathway. This document discusses the version of CCLUB released September 30, 2018, which includes five ethanol LUC scenarios and four soy biodiesel LUC scenarios.
Cobalt Life Cycle Analysis Update for the GREET® Model
Q. Dai, J. Kelly, A. Elgowainy
http://greet.es.anl.gov/publication-update_cobalt
This memo documents updates for life cycle analysis (LCA) of cobalt and cobalt chemicals production in the GREET model. The updated life cycle inventory (LCI) covers material and energy flows associated with cobalt ore mining, cobalt ore processing, cobalt chemicals production, cobalt metal production, and pertinent transportation activities. Based on recent literature, industry statistics, and company reports, these updates represent current practices of the global cobalt industry, and will be incorporated into GREET 2018.
China Vehicle Fleet Model: Estimation of Vehicle Stocks, Usage, Emissions, and Energy Use - Model Description, Technical Documentation, and User Guide
Z. Lu, Y. Zhou, H. Cai, M. Wang, X. He, S. Przesmitzki
http://greet.es.anl.gov/publication-china_fleet_model_2018
This report introduces the China Vehicle Fleet Model developed by Argonne National Laboratory (Argonne). The model includes different vehicle classes, their market shares, fleet turnover, and estimation of long-term energy use and GHG emissions associated with the vehicle fleet in China up to the year 2050. The model also aims to evaluate the impacts of alternative vehicle technologies, alternative fuels, future regulations, and potential policies on the energy use and GHG emissions of the Chinese highway transportation sector.
http://greet.es.anl.gov/publication-update_ng_2018
Argonne National Laboratory researchers have been analyzing the environmental impacts of natural gas (NG) production and use for more than 15 years. With the rapid development of shale gas production in the past few years, significant efforts have been made to examine various stages of natural gas pathways to estimate their life-cycle impacts. In 2011, Argonne researchers examined the uncertainty associated with key parameters for shale gas and conventional NG pathways to identify data gaps that required further attention (Clark et al. 2011). Clark et al. (2011) based much of their analysis of methane (CH4) emissions on the United States Environmental Protection Agency's (EPA's) 2011 greenhouse gas inventory (GHGI), as this was the first EPA GHGI to incorporate shale gas and included significant revisions to its liquid unloading leakage estimates (EPA 2011). In addition, the report examined the water, materials, and fuel needed to drill and construct NG wells. From 2013 to 2016, Argonne researchers updated the GREET model based on EPA's latest GHG inventories, which included several methodological changes for estimating natural gas CH4 emissions (Burnham et al. 2013; Burnham et al. 2014; Burnham et al. 2015; Burnham 2016). In 2015 and 2017, Argonne analyzed the environmental impacts, including CH4 leakage and air pollutant emissions, of heavy-duty natural gas vehicles (Cai et al. 2015; Cai et al. 2017). In 2017, GREET was updated based on the work documented in Cai et al. (2017), which examined natural gas vehicle upstream freshwater consumption, greenhouse gas (GHG) emissions, and nitrogen oxides (NOx) and particulate matter (PM) emissions as well as supplementary analysis of the 2017 EPA GHGI (Burnham 2017).
Updated vented, flaring, and fugitive greenhouse gas emissions for crude oil production in the GREET1_2018 model
L. Ou, H. Cai
http://greet.es.anl.gov/publication-update_ghg_emi_2018
Life-cycle analysis of greenhouse gas (GHG) emissions of petroleum fuels pathways requires careful accounting of GHG emissions from both process fuel combustion and non-combustion activities associated with crude oil production and storage, transportation, refining operations, distribution of fuels and their end use by vehicles. Vented, fugitive, and flaring (VFF) CH4 and CO2 emissions can be released to the atmosphere during crude oil production processes (U.S. Environmental Protection Agency, 2018). Argonne researchers regularly estimate such emissions for modeling petroleum-based fuel pathways in the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREETTM) model primarily based on the annual GHG Emission Inventory Report by United States Environmental Protection Agency (EPA). Recently, EPA has adopted new data and methodology to estimate CH4 and CO2 emissions for petroleum systems (U.S. Environmental Protection Agency, 2018). These revisions caused changes to the VFF CH4 and CO2 emissions from domestic crude oil production in the U.S. The aim of this technical memorandum is to update VFF CH4 and CO2 emissions in the GREET model by incorporating these revisions in the latest EPA GHG emission inventory.
Summary of expansions and updates in GREET® 2018
M. Wang, A. Elgowainy, P. Benavides, A. Burnham, H. Cai, Q. Dai, T. Hawkins, J. Kelly, H. Kwon, D. Lee, U. Lee, Z. Lu, L. Ou
The GREET® (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model has been developed by Argonne National Laboratory (Argonne) with the support of the U.S. Department of Energy (DOE). GREET is a life-cycle analysis (LCA) tool, structured to systematically examine energy and environmental effects of a wide variety of transportation fuels and vehicle technologies in major transportation sectors (i.e., road, air, marine, and rail). There are two GREET modeling platforms; GREET Excel is a multidimensional spreadsheet model that provides a comprehensive LCA tool, and GREET.Net provides an interactive graphical toolbox to perform LCA. The GREET 2018 release includes expansions and updates for both platforms, and this report provides a summary of the release.
Environmental, economic, and scalability considerations and trends of selected fuel economy-enhancing biomass-derived blendstocks
J. Dunn, M. Biddy, S. Jones, H. Cai, P. Benavides, J. Markham, L. Tao, E. Tan, C. Kinchin, R. Davis, A. Dutta, M. Bearden, C. Clayton, S. Phillips, K. Rappé, P. Lamers
http://greet.es.anl.gov/publication-fe_enhancing_bios
Twenty-four biomass-derived compounds and mixtures, identified based on their physical properties, which could be blended into fuels to improve spark ignition engine fuel economy, were assessed for their economic, technology readiness, and environmental viability. These bio-blendstocks were modeled to be produced biochemically, thermochemically, or through hybrid processes. To carry out the assessment, 17 metrics were developed for which each bio-blendstock was determined to be favorable, neutral, or unfavorable. Cellulosic ethanol was included as a reference case. Overall economic and, to some extent, environmental viability is driven by projected yields for each of these processes. The metrics used in this analysis methodology highlight the near-term potential to achieve these targeted yield estimates when considering data quality and current technical readiness for these conversion strategies. Key knowledge gaps included the degree of purity needed for use as a bio-blendstock. Less stringent purification requirements for fuels could cut processing costs and environmental impacts. Additionally, more information is needed on the blending behavior of many of these bio-blendstocks with gasoline to support the technology readiness evaluation. Overall, the technology to produce many of these blendstocks from biomass is emerging, and as it matures, these assessments must be revisited. Importantly, considering economic, environmental, and technology readiness factors, in addition to physical properties of blendstocks that could be used to boost engine efficiency and fuel economy, in the early stages of project research and development can help spotlight those most likely to be viable in the near term.
Update of bill-of-materials and cathode materials production for lithium-ion batteries in the GREET® model
Q. Dai, J. Kelly, J. Dunn, P. Benavides
http://greet.es.anl.gov/publication-update_bom_cm
This memo documents updates in the GREET model for 1) bill-of-materials (BOMs) of lithium-ion batteries (LIBs) for electric vehicles (EVs), including hybrid electric vehicles (HEVs), plug-in hybrid vehicles (PHEVs), and battery electric vehicles (BEVs); 2) life cycle inventory (LCI) for the production of LIB cathode materials, including lithium cobalt oxide (LCO), lithium nickel cobalt manganese oxide (NMC), and lithium nickel cobalt aluminum oxide (NCA). The BOM update was based on the most recent version of Argonne's Battery Performance and Cost (BatPaC) model. The cathode LCI update was based on our site visit to one leading cathode material producer, literature, and industry reports. These updates therefore represent current material compositions of LIB for transportation applications and the state-of-the-art of industrial production of LIB cathode materials, and are incorporated into GREET 2018.
Railroad Energy Intensity and Criteria Air Pollutant Emissions
A. Elgowainy, A. Vyas, M. Biruduganti, M. Shurland
http://greet.es.anl.gov/publication-railroad-2018
From June 30, 2014, to March 20, 2016, the Argonne National Laboratory (Argonne) was contracted by the Federal Railroad Administration (FRA) to update Argonne's Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET®) model to include a rail module. Argonne was also tasked to use that module to evaluate the life-cycle cost of using of compressed natural gas, liquefied natural gas or dimethyl ether as possible alternative locomotive fuels from an energy and emissions perspective. The study fully evaluated energy and emission impacts of advanced vehicle technologies, including new transportation fuels, the fuel cycle from wells to wheels, and the vehicle cycle through material recovery and vehicle disposal. With sponsorship from the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE), Argonne developed GREET® in 1996 as a full life-cycle model that allowed researchers and analysts to evaluate various vehicle and fuel combinations on a full fuel-cycle/vehicle-cycle basis.
Assessment of algal biofuel resource potential in the United States with consideration of regional water stress
H. Xu, U. Lee, A. Coleman, M. Wigmosta, M. Wang
https://www.sciencedirect.com/science/article/pii/S221192641830835X
http://greet.es.anl.gov/publication-algal_w_water
Algae is a promising feedstock for biofuels. Because scaling up the production of algae-based biofuels consumes a significant amount of water, it is important to consider the impact it has on water stress. This study evaluates the potential for algae-derived biofuel production in the United States (US) and considers regional water stress. We used the Biomass Assessment Tool (BAT) to identify potential sites in the US that meet land, biomass productivity, and CO2 co-locating criteria. We quantify the water stress impacts of algal biofuel production in terms of water scarcity footprint using water consumption from BAT, and the water stress indicator from Available Water Remaining for the US (AWARE-US) system. We assess long-term (20 billion gal per year [BGY]) and near-term (5 BGY by 2030) renewable diesel (RD) production targets. To select suitable algae sites, we consider biomass yield and water use with and without water stress constraints. We found that ranking sites based on biomass yield results in a high water stress impact (24.5 × 103 US equivalent BGY [BGYe]) for the long-term RD target. If we instead rank sites on water use efficiency, water consumption decreases on average by 62%, with an average reduction in biomass yield of 25%. To reconcile tradeoffs between biomass yield and water stress impacts, water stress indicator (AWARE-US) that represents relative water availability by region can be applied while considering biomass yield. This strategy removes sites located in water-stressed areas and keeps high-productivity sites. For the long-term RD target, this reduces water stress impacts by 55% (13.8 BGYe) without lowering yield or 97% (24.2 BGYe) with moderately lower (4%) yield, compared to the sites ranked by biomass yield alone. The results demonstrate that incorporating water stress into energy-scale algae biofuel production planning is key to achieving synergies between biofuel yield and fresh water stress impacts.
Supply chain sustainability analysis of renewable hydrocarbon fuels via indirect liquefaction, ex situ catalytic fast pyrolysis, hydrothermal liquefaction, and biochemical conversion: update of the 2018 state-of-technology cases and design cases
H. Cai, T. Benavides, U. Lee, M. Wang, E. Tan, R. Davis, A. Dutta, M. Biddy, J. Clippinger, N. Grundl, L. Tao, D. Hartley, M. Roni, D. Thompson, L. Snowden-Swan, Y. Zhu, S. Jones
http://greet.es.anl.gov/publication-supply_renewable_hc
The Department of Energy's (DOE's) Bioenergy Technologies Office (BETO) aims to develop and deploy technologies to transform renewable biomass resources into commercially viable, high-performance biofuels, bioproducts and biopower through public and private partnerships (U.S. Department of Energy 2016). BETO and its national laboratory teams conduct in-depth techno-economic assessments (TEA) of biomass feedstock supply and logistics and conversion technologies to produce biofuels. There are two general types of TEAs: A design case is a TEA that outlines a target case (future projection) for a particular biofuel pathway. It enables identification of data gaps and research and development needs, and provides goals and benchmarks against which technology progress is assessed. A state of technology (SOT) analysis assesses progress within and across relevant technology areas based on actual results at current experimental scales, relative to technical targets and cost goals from design cases, and includes technical, economic, and environmental criteria as available. In addition to developing a TEA for a pathway of interest, BETO also performs a supply chain sustainability analysis (SCSA). The SCSA takes the life-cycle analysis approach that BETO has been supporting for more than 19 years. It enables BETO to identify energy consumption, environmental, and sustainability issues that may be associated with biofuel production. Approaches to mitigate these issues can then be developed. Additionally, the SCSA allows for comparison of energy and environmental impacts across biofuel pathways in BETO's research and development portfolio. This technical report describes the SCSAs for the production of renewable hydrocarbon transportation fuels via a range of conversion technologies: (1) renewable high octane gasoline (HOG) via indirect liquefaction (IDL) of woody lignocellulosic biomass (note that the IDL pathway in this SCSA represents the syngas conversion design in the 2018 SOT and 2022 design cases [Tan et al., 2018]); (2) renewable gasoline (RG) and diesel (RD) blendstocks via ex situ catalytic fast pyrolysis of woody lignocellulosic biomass; (3) RD via hydrothermal liquefaction (HTL) of wet sludge from a wastewater treatment plant; (4) renewable hydrocarbon fuels via biochemical conversion of herbaceous lignocellulosic biomass; (5) renewable diesel via HTL of a blend of algae and woody biomass; and (6) renewable diesel via combined algae processing (CAP). This technical report focuses on the environmental performance of these six biofuel production pathways in their 2018 SOT cases, as well as in their design cases (future target projections). The results of these renewable hydrocarbon fuel pathways in these SCSA analyses update those for the respective 2015 and 2016 SOT cases (Edward Frank et al. 2016; Hao Cai et al. 2016, 2017; Cai et al. 2018) in the case of IDL, algae CAP, and biochemical conversion pathways. They also provide an opportunity to examine the impact of technology improvements in both biomass feedstock production and biofuel production that have been achieved in 2018 SOTs on the sustainability performance of these renewable transportation fuels, and they reflect updates to Argonne National Laboratory's Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET®) model, which was released in October 2018 (Wang et al. 2018). These GREET updates include production of natural gas, electricity, and petroleum-based fuels that can influence biofuels' supply chain greenhouse gas (GHG) (CO2, CH4, and N2O) emissions, water consumption and air pollutant emissions. GHG emissions, water consumption, and nitrogen oxides (NOx) emissions are the main sustainability metrics assessed in this analysis. In this analysis, we define water consumption as the amount of water withdrawn from a freshwater source that is not returned (or returnable) to a freshwater source at the same level of quality. Life-cycle fossil energy consumption and net energy balance, which is the life-cycle fossil energy consumption deducted from the renewable biofuel energy produced, are also assessed.
Criteria Air Pollutants and Greenhouse Gas Emissions from Hydrogen Production in U.S. Steam Methane Reforming Facilities
P. Sun, B. Young, A. Elgowainy, Z. Lu, M. Wang, B. Morelli, T. Hawkins
https://pubs.acs.org/doi/full/10.1021/acs.est.8b06197
http://greet.es.anl.gov/publication-cap_ghg_h2_smr
The global and U.S. domestic effort to develop a clean energy economy and curb environmental pollution incentivizes the use of hydrogen as a transportation fuel, owing to its zero tailpipe pollutant emissions and high fuel efficiency in fuel cell electric vehicles (FCEVs). However, the hydrogen production process is not emissions free. Conventional hydrogen production via steam methane reforming (SMR) is energy intensive, coproduces carbon dioxide, and emits air pollutants. Thus, it is necessary to quantify the environmental impacts of SMR hydrogen production alongside the use-phase of FCEVs. This study fills the information gap, analyzing the greenhouse gas (GHG) and criteria air pollutant (CAP) emissions associated with hydrogen production in U.S. SMR facilities by compiling and matching the facility-reported GHG and CAP emissions data with facilities' hydrogen production data. The actual amounts of hydrogen produced at U.S. SMR facilities are often confidential. Thus, we have developed four approaches to estimate the hydrogen production amounts. The resultant GHG and CAP emissions per MJ of hydrogen produced in individual facilities were aggregated to develop emission values for both a national median and a California state median. This study also investigates the breakdown of facility emissions into combustion emissions and noncombustion emissions.
Criteria Air Pollutant and Greenhouse Gases Emissions from U.S. Refineries Allocated to Refinery Products
http://greet.es.anl.gov/publication-cap_ghg_refinery
Using Greenhouse Gas Reporting Program data (GHGRP) and National Emissions Inventory data from 2014, we investigate U.S. refinery greenhouse gas (GHG) emissions (CO2, CH4, and N2O) and criteria air pollutant (CAP) emissions (VOC, CO, NOx, SO2, PM10, and PM2.5). The study derives (1) combustion emission factors (EFs) of refinery fuels (e.g., refinery catalyst coke and refinery combined gas), (2) U.S. refinery GHG emissions and CAP emissions per crude throughput at the national and regional levels, and (3) GHG and CAP emissions attributable to U.S. refinery products. The latter two emissions were further itemized by source: combustion emission, process emission, and facility-wide emission. We estimated U.S. refinery product GHG and CAP emissions via energy allocation at the refinery process unit level. The unit energy demand and unit flow information were adopted from the Petroleum Refinery Life Cycle Inventory Model (PRELIM version 1.1) by fitting individual U.S. refineries. This study fills an important information gap because it (1) evaluates refinery CAP emissions along with GHG emissions and (2) provides CAP and GHG emissions not only for refinery main products (gasoline, diesel, jet fuel, etc.) but also for refinery secondary products (asphalt, lubricant, wax, light olefins, etc.).
A global meta‐analysis of soil organic carbon response to corn stover removal
H. Xu, H. Sieverding, H. Kwon, D. Clay, C. Stewart, J. Johnson, Z. Qin, D. Karlen, M. Wang
https://onlinelibrary.wiley.com/doi/full/10.1111/gcbb.12631
http://greet.es.anl.gov/publication-soc_corn_stover
Corn (Zea mays L.) stover is a global resource used for livestock, fuel, and bioenergy feedstock, but excessive stover removal can decrease soil organic C (SOC) stocks and deteriorate soil health. Many site‐specific stover removal experiments report accrual rates and SOC stock effects, but a quantitative, global synthesis is needed to provide a scientific base for long‐term energy policy decisions. We used 409 data points from 74 stover harvest experiments conducted around the world for a meta‐analysis and meta‐regression to quantify removal rate, tillage, soil texture, and soil sampling depth effects on SOC. Changes were quantified by: (a) comparing final SOC stock differences after at least 3 years with and without stover removal and (b) calculating SOC accrual rates for both treatments. Stover removal generally reduced final SOC stocks by 8% in the upper 0–15 or 0–30 cm, compared to stover retained, irrespective of soil properties and tillage practices. A more sensitive meta‐regression analysis showed that retention increased SOC stocks within the 30–150 cm depth by another 5%. Compared to baseline values, stover retention increased average SOC stocks temporally at a rate of 0.41 Mg C ha−1 year−1 (statistically significant at p < 0.01 when averaged across all soil layers). Although SOC sequestration rates were lower with stover removal, with moderate (<50%) removal they can be positive, thus emphasizing the importance of site‐specific management. Our results also showed that tillage effects on SOC stocks were inconsistent due to the high variability in practices used among the experimental sites. Finally, we conclude that research and technological efforts should continue to be given high priority because of the importance in providing science‐based policy recommendations for long‐term global carbon management.
Globally regional life cycle analysis of automotive lithium-ion nickel manganese cobalt batteries
J. Kelly, Q. Dai, M. Wang
https://link.springer.com/article/10.1007%2Fs11027-019-09869-2
http://greet.es.anl.gov/publication-global_nmc_lib_lca
Electric vehicles based on lithium-ion batteries (LIB) have seen rapid growth over the past decade as they are viewed as a cleaner alternative to conventional fossil-fuel burning vehicles, especially for local pollutant (nitrogen oxides [NOx], sulfur oxides [SOx], and particulate matter with diameters less than 2.5 and 10 μm [PM2.5 and PM10]) and CO2 emissions. However, LIBs are known to have their own energy and environmental challenges. This study focuses on LIBs made of lithium nickel manganese cobalt oxide (NMC), since they currently dominate the United States (US) and global automotive markets and will continue to do so into the foreseeable future. The effects of globalized production of NMC, especially LiNi1/3Mn1/3Co1/3O2 (NMC111), are examined, considering the potential regional variability at several important stages of production. This study explores regional effects of alumina reduction and nickel refining, along with the production of NMC cathode, battery cells, and battery management systems. Of primary concern is how production of these battery materials and components in different parts of the world may impact the battery's life cycle pollutant emissions and total energy and water consumption. Since energy sources for heat and electricity generation are subject to great regional variation, we anticipated significant variability in the energy and emissions associated with LIB production. We configured Argonne National Laboratory's Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model as the basis for this study with key input data from several world regions. In particular, the study examined LIB production in the US, China, Japan, South Korea, and Europe, with details of supply chains and the electrical grid in these regions. Results indicate that 27-kWh automotive NMC111 LIBs produced via a European-dominant supply chain generate 65 kg CO2e/kWh, while those produced via a Chinese-dominant supply chain generate 100 kg CO2e/kWh. Further, there are significant regional differences for local pollutants associated with LIB, especially SOx emissions related to nickel production. We find that no single regional supply chain outperforms all others in every evaluation metric, but the data indicate that supply chains powered by renewable electricity provide the greatest emission reduction potential.
Update of Direct N2O Emission Factors from Nitrogen Fertilizers in Cornfields
H. Xu, H. Cai, H. Kwon
http://greet.es.anl.gov/publication-n2o_update_2019
Corn farming requires intensive nitrogen fertilizer input. When applied in cornfield, a portion of nitrogen fertilizers is directly converted to nitrous oxide (N2O) through the soil microbial processes of nitrification and denitrification and released to the atmosphere. In addition to direct N2O emissions, N2O emissions can also be produced through indirect processes including volatilization of nitrogen fertilizers and leaching and runoff of nitrate from the fertilizers. In 2012, Argonne National Laboratory estimated a direct nitrogen fertilizer-induced emission factor (hereafter direct N2O EF) of 1.2% through literature review (Wang et al. 2012). Since then, according to Web of Science, about 263 new studies on this topic have been published. This technical memorandum documents a new update aiming to expand the previous literature review with new studies to reflect recent empirical evidences of nitrogen fertilizer-induced N2O emissions.
Life Cycle Inventory for Polylactic Acid Production
P. Benavides, O. Zare`-Mehrjerdi, U. Lee
http://greet.es.anl.gov/publication-pla_lca
Polylactic acid (PLA) is a linear aliphatic thermoplastic polyester with three stereochemical forms: poly-L-lactide, poly-D-lactide, and poly-D,L-lactide [Nampoothiri et al. 2010]. In 2017, PLA production accounted for around 10% of global bioplastic production (232,749 tons) and is expected to have a significant increase in production capability to 50% percent by 2022 compared [European Bioplastics 2017; Detzel et al. 2013]. It is estimated that bioplastics can replace as much as 90% of the application used by conventional plastics, which show the great potential of bio-based plastics [Shen et al. 2010]. PLA has a proven track record as a substitute for more commonly used plastics such as polypropylene (PP), high density polyethylene, acrylonitrile butadiene styrene, and more [Guo and Crittenden 2011; Groot and Boren 2010]. PLA is a potential replacement for conventional plastics applications such as cups, bottles, to-go containers, packaging, films, and textiles [Henton et al. 2005; Binder and Woods 2009; Vaes et al. 2006; Gironi and Piemonte 2011; Vink et al. 2003]. In this document, we present a life-cycle inventory (LCI) for PLA production that can be used to evaluate the energy and material inputs with the greatest effect on the life-cycle energy use and greenhouse gas (GHG) emissions of PLA production. For this purpose, we used the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model, which Argonne National Laboratory developed [GREET 2018]. GREET was used to collect data for the upstream processes of PLA production including energy use and emission factors.
Updates of Hydrogen Production from SMR Process in GREET® 2019
P. Sun, A. Elgowainy
http://greet.es.anl.gov/publication-smr_h2_2019
The hydrogen production pathway using steam methane reforming (SMR) of natural gas (NG) is updated in GREET 2019, based on a recent study by Sun et al. (2019). This study investigated U.S. stand-alone SMR facilities and reported criteria air pollutant (CAP) and greenhouse gas (GHG) emissions per unit of hydrogen production, using SMR facility emission data reported in the National Emissions Inventory (NEI) and the Greenhouse Gas Reporting Program (GHGRP) databases, respectively. The study summarized the CO2 emission associated with hydrogen production by accounting for emissions both from combustion and chemical conversion processes. The median CO2 emission normalized for SMR hydrogen production was 9 kg CO2/kg H2 production, or 75 g CO2/MJ H2 (using H2 low heating value [LHV]). The median emission is similar with the value of 9.26 kg CO2/kg H2 in GREET 2018, which was based on the H2A modeling by Rutkowski et al (2012). For other emissions, the combustion and non-combustion CAP emissions, based on NEI data from Sun et al (2019), reported lower values compared to GREET 2018.
Emissions Updates For Petroleum Products in GREET 2019
P. Sun, Z. Lu
http://greet.es.anl.gov/publication-petro_2019
The GREET model was updated in petroleum pathways in 2019, based on recent research results by Sun et al.
Updates for Battery Recycling and Materials in GREET 2019
Q. Dai, O. Winjobi
http://greet.es.anl.gov/publication-battery_recycling_materials_2019
This memo documents updates in GREET 2019 for (1) four pathways to recycle lithium-ion batteries (LIBs) at the cell level, including a pyrometallurgical recycling pathway, a hydrometallurgical recycling pathway based on inorganic leaching, a hydrometallurgical recycling pathway based on organic leaching, and a direct recycling pathway; (2) material requirements for the production of battery-grade nickel sulfate; (3) life cycle inventory (LCI) for the production of lithium hydroxide; and (4) water consumption for limestone mining.
Updated Natural Gas Pathways in the GREET 1_2019 Model
In 2018, we added the option to use emissions data from Alvarez et al. (2018) for GREET1_2018 (Burnham 2018). The data from Alvarez et al. (2018) is referred to as EDF 2019 in GREET1_2019. However, we continue to use the latest EPA GHGI to update default CH4 emissions data in GREET. We find the EPA GHGI to be the best data source that provides detailed process-level emissions needed to update GREET. As the EPA updates its GHGI annually, we will continue to evaluate the latest data in this area and update GREET accordingly.
M. Wang, A. Elgowainy, U. Lee,P. Benavides, A. Burnham, H. Cai, Q. Dai, T. Hawkins, J. Kelly, H. Kwon, X. Liu, Z. Lu, L. Ou, P. Sun, O. Winjobi, H. Xu
The GREET® (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model has been developed by Argonne National Laboratory (Argonne) with the support of the U.S. Department of Energy (DOE). GREET is a life-cycle analysis (LCA) tool, structured to systematically examine the energy and environmental effects of a wide variety of transportation fuels and vehicle technologies in major transportation sectors (i.e., road, air, marine, and rail). Argonne has expanded and updated the model in various sectors in GREET 2019, and this report provides a summary of the release.
Life Cycle Analysis (LCA) of Petroleum-Based Fuels with the GREET® Model
A. Elgowainy, Z. Lu, P. Sun
http://greet.es.anl.gov/publication-workshop_2019_petroleum
The GREET Introduction Workshop Argonne National Laboratory, October 15, 2019
Life Cycle Analysis (LCA) of Biofuels and Land Use Change with the GREET® Model
H. Kwon, U. Lee
http://greet.es.anl.gov/publication-workshop_2019_biofuel_luc
Life Cycle Analysis (LCA) of BEV and H2 FCEV with the GREET® Model
A. Elgowainy, J. Kelly, Q. Dai, P. Sun, X. Liu
http://greet.es.anl.gov/publication-workshop_2019_bev_h2fcev
Overview of Life Cycle Analysis (LCA) with the GREET® Model
http://greet.es.anl.gov/publication-workshop_2019_overview
Environmental Life Cycle Assessment of U.S. Concrete
T. Hottle, T. Hawkins, C. Chiquelin, B. Lange, B. Young, P. Sun, M. Wang
http://greet.es.anl.gov/publication-cement_concrete_2019
Comparison of well-to-wheels energy use and emissions of a hydrogen fuel cell electric vehicle relative to a conventional gasoline-powered internal combustion engine vehicle
X. Liu, K. Reddi, A. Elgowainy, H. Lohse-Busch, M. Wang, N. Rustagi
https://www.sciencedirect.com/science/article/pii/S0360319919340650?via%3Dihub
http://greet.es.anl.gov/publication-wtw_fcv_vs_icev
The operation of hydrogen fuel cell electric vehicles (HFCEVs) is more efficient than that of gasoline conventional internal combustion engine vehicles (ICEVs), and produces zero tailpipe pollutant emissions. However, the production, transportation, and refueling of hydrogen are more energy- and emissions-intensive compared to gasoline. A well-to-wheels (WTW) energy use and emissions analysis was conducted to compare a HFCEV (Toyota Mirai) with a gasoline conventional ICEV (Mazda 3). Two sets of specific fuel consumption data were used for each vehicle: (1) fuel consumption derived from the U.S. Environmental Protection Agency's (EPA's) window-sticker fuel economy figure, and (2) weight-averaged fuel consumption based on physical vehicle testing with a chassis dynamometer on EPA's five standard driving cycles. The WTW results show that a HFCEV, even fueled by hydrogen from a fossil-based production pathway (via steam methane reforming of natural gas), uses 5%–33% less WTW fossil energy and has 15%–45% lower WTW greenhouse gas emissions compared to a gasoline conventional ICEV. The WTW results are sensitive to the source of electricity used for hydrogen compression or liquefaction.
Regional-level analysis for the material flows and process energy demands of aluminum and steel in the American automotive industry
N. Hua, G. Keoleian, G. Lewis
http://css.umich.edu/publication/regional-level-analysis-material-flows-and-process-energy-demands-aluminum-and-steel
http://greet.es.anl.gov/publication-regional_al_steel
Aluminum and steel dominate the material composition of American light duty vehicles (LDV), representing 12% and 54% of an LDV's curb weight, respectively, as of 2018 (Ducker FSG Holdings, LLC [Ducker], 2018). With rising concerns about the American automotive sector's sustainability, gaining a better understanding of the automotive aluminum and steel supply chains can provide valuable insight towards better assessing the energy demand and greenhouse gas burden of a vehicle's materials on a global and regional basis. This study details the development of a method and framework for regionally linked, sector specific material flow analysis (MFA) models and presents the results of such models for aluminum and steel entering the American automotive industry (henceforth termed automotive aluminum and automotive steel). Additionally, the models facilitate a regionalized perspective of the process energy demands associated with automotive aluminum and steel, including their respective raw materials
Balancing Water Sustainability and Productivity Objectives in Microalgae Cultivation: Siting Open Ponds by Considering Seasonal Water-Stress Impact Using AWARE-US
H. Xu, U. Lee, A. Coleman, M. Wigmosta, N. Sun, T. Hawkins, M. Wang
https://pubs.acs.org/doi/10.1021/acs.est.9b05347
http://greet.es.anl.gov/publication-microalgae_cultivation
Microalgae have great potential as an energy and feed resource. Here we evaluate the water use associated with freshwater algae cultivation and find it is possible to scale U.S. algae biofuel production to 20.8 billion liters of renewable diesel annually without significant water-stress impact. Among potential sites, water-stress is significantly more variable than algae productivity across location and season. Thus, it is possible to reduce water-stress impact, quantified as water scarcity footprint, through the choice of algae site location. We test three site-selection criteria based on (1) biomass productivity, (2) water-use efficiency, and (3) water-stress impact and find that adding water-stress constraints to productivity-based ranking of suitable sites reduces water-stress impact by 97% and water consumption by half, compared with biomass-productivity ranking alone, with little productivity impact (<1.7% per-site on average). With 20.8 billion liters, algae could meet 19.7% of U.S. jet fuel demand with a freshwater demand of less than 1.4% of U.S. irrigation consumption. Evaluating water-stress impact is important because the impact of unit water consumption on water stress varies significantly across regions and seasons. Considering seasonal water balances allows producers to understand the combined seasonal effects of hydrologic flows and productivity, thereby avoiding potential short-term water stress.
Summary and Instructions for Monthly AWARE-US Model (Public Version)
H. Xu, U. Lee, T. Hawkins, M. Wang
http://greet.es.anl.gov/publication-aware_us_instr
Freshwater is a critical resource to sustain both societal needs and ecosystem services. Although freshwater is a renewable resource that can be replenished through hydrological cycles, increasing demand from existing and new societal needs, including energy system deployments, may exacerbate water-stress. Traditionally, water footprint approach, which sums up consumptive water use along the supply chain, has been the primary method used in life-cycle analyses to account for water use impact (Lee et al., 2019). However, both freshwater supply and demand vary substantially across the United States, therefore impact of water consumption on local water resource should reflect spatial variations in water availability (Xu et al., 2019b). To enable cross regional comparison of water-stress impact of regional water consumption scenarios, Argonne National Laboratory developed the Available Water Remaining for the United States (AWARE-US) model (Lee et al., 2019). AWARE-US used the global AWARE framework proposed by the Water Use in LCA (WULCA) Working group (Boulay et al., 2018). Argonne improved it by incorporating observed freshwater supply and demand data and refining the spatial scale at the U.S. county level. The AWARE-US model has been applied to evaluate the water stress impact caused by water consumed for the deployment of hydrogen fuel cell vehicles and algae biofuel production in the United States (Lee et al., 2019; Xu et al., 2019a). In addition, because water availability also changes seasonally, Argonne developed a monthly version of AWARE-US model to enable seasonal water-stress impact assessment (Xu et al., 2020). To support easy-access and interactive analysis, we developed an online version AWARE-US model which is publicly available at https://greet.es.anl.gov/awareus. This report provides a summary of the monthly AWARE-US model, and instructions for using the web-based water stress analysis model. More details regarding the development and the applications of AWARE-US can be found in our previous publications (Lee et al., 2019; Xu et al., 2020, 2019a).
Supply Chain Sustainability Analysis of Renewable Hydrocarbon Fuels via Indirect Liquefaction, Ex Situ Catalytic Fast Pyrolysis, Hydrothermal Liquefaction, Combined Algal Processing, and Biochemical Conversion: Update of the 2019 State-of-Technology Cases
H. Cai, L. Ou, M. Wang, E. Tan, R. Davis, A. Dutta, L. Tao, D. Hartley, M. Roni, D. Thompson, L. Snowden-swan, Y. Zhu
http://greet.es.anl.gov/publication-renewable_hc_2019
This technical report describes the SCSAs for the production of renewable hydrocarbon transportation fuels via a range of conversion technologies: (1) renewable high octane gasoline (HOG) via indirect liquefaction (IDL) of woody lignocellulosic biomass (note that the IDL pathway in this SCSA represents the syngas conversion design in the 2019 SOT [Tan et al. 2019]); (2) renewable gasoline (RG) and diesel (RD) blendstocks via ex situ catalytic fast pyrolysis of woody lignocellulosic biomass; (3) RD via hydrothermal liquefaction (HTL) of wet sludge from a wastewater treatment plant; (4) renewable hydrocarbon fuels via biochemical conversion of herbaceous lignocellulosic biomass; (5) renewable diesel via HTL of a blend of algae and woody biomass; and (6) renewable diesel via combined algae processing (CAP). This technical report focuses on the environmental performance of these six biofuel production pathways in their 2019 SOT cases. The results of these renewable hydrocarbon fuel pathways in these SCSA analyses update those for the respective 2018 SOT cases (Cai et al., 2018a). They also provide an opportunity to examine the impact of technology improvements in both biomass feedstock production and biofuel production that have been achieved in 2019 SOTs on the sustainability performance of these renewable transportation fuels, and they reflect updates to Argonne National Laboratory's Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET®) model, which was released in October 2019 (Wang et al., 2019). These GREET updates include the production of natural gas, electricity, and petroleum-based fuels that can influence biofuels' supply chain greenhouse gas (GHG) (CO2, CH4, and N2O) emissions, water consumption, and air pollutant emissions. GHG emissions, water consumption, and nitrogen oxides (NOx) emissions are the main sustainability metrics assessed in this analysis. In this analysis, we define water consumption as the amount of water withdrawn from a freshwater source that is not returned (or returnable) to a freshwater source at the same level of quality. Life-cycle fossil energy consumption and net energy balance, which is the life-cycle fossil energy consumption deducted from the renewable biofuel energy produced, are also assessed.
Chapter 8 - Life cycle analysis of waste-to-energy pathways
U. Lee, P. Benavides, M. Wang
https://www.sciencedirect.com/science/article/pii/B9780128163948000082
http://greet.es.anl.gov/publication-lca_waste_2_energy
Life-cycle analysis (LCA) is a method that evaluates the environmental impacts of various pathways such as life-cycle greenhouse gas (GHG) emissions, energy use, and water consumption along the supply chain. In this chapter, we discuss how LCA can be used to examine the waste-to-energy (WTE) technologies. We introduce three major WTE feedstocks (organic waste, waste plastics, and waste gas) for energy production and corresponding conversion technologies such as anaerobic digestion, combustion, hydrothermal liquefaction, pyrolysis, and gas fermentation. Besides, major LCA parameters are discussed. The results show that emissions from current waste management (business-as-usual [BAU]) significantly influence the LCA results, and careful examination is needed due to the huge variations and uncertainties in the BAU cases. WTE practices can change waste into resources, which generates additional energy products while providing environmental benefits such as reductions in life cycle GHG emissions.
Life cycle energy and environmental impacts of concrete: GREET update
T. Hawkins, T. Hottle, B. Young, C. Chiquelin, B. Lange, P. Sun, M. Wang
http://greet.es.anl.gov/publication-lca_concrete_update
Project Update Briefing
GREET Factsheet 2020
http://greet.es.anl.gov/publication-greet_factsheet_2020
GREET is a suite of models that examine the life-cycle impacts of efficiency technologies and energy systems for energy and technology producers, researchers, and regulators.
Regional and seasonal water stress analysis of United States thermoelectricity
U. Lee, J. Chou, H. Xu, D. Carlson, A. Venkatesh, E. Shuster, T. Skone, M. Wang
http://greet.es.anl.gov/publication-regional_us_water_thermoelectricity
Most thermoelectric power plants in the United States (U.S.) rely on fresh water for cooling, resulting in significant water consumption. An understanding of the regional and seasonal water stress impact of such water consumption is needed. In this study, we used a U.S. county-level water stress index, Available Water Remaining for the United States (AWARE-US), with facility-level thermoelectric power generation water consumption data, to quantify the regional and seasonal water stress impact of U.S. thermoelectric power plants. Water stress impact was evaluated as water-scarcity footprint (WSF) using monthly AWARE-US data. Results show that most thermoelectric power plants in the United States that use fresh water are in water-abundant regions. Our findings also show that a small fraction of the U.S. thermoelectric generation facilities (13% by power) located in water stressed regions contribute the most water stress impact (88% of the total WSF) caused by thermoelectric power generation in the U.S. Even if fresh water is abundant on an annual basis, many power plants are in counties with seasonal water shortages. Of the 401 counties with thermoelectric power plants using fresh water for cooling, 80 counties in February and 160 counties in August had fresh water withdrawal requirements that exceeded the sustainable fresh water available (availability minus demand or AMD) in that region. This means that 27% and 46% of power generation facilities have difficulty securing sustainable fresh water in February and August, respectively. This study is intended to support water consumption management in existing power plants and guide the deployment of future power plants to mitigate water stress impact.
Light-Duty Vehicle Cost Markup Analysis: Literature Review and Evaluation
J. Kelly
http://greet.es.anl.gov/publication-ldv_cost_literature
Knowledge of historical automotive manufacturing costs and intended sale prices of vehicles is important in understanding the costs and prices of current and emerging vehicle technologies, as well as the types of technology choices that original equipment manufacturers (OEMs) may make with their technology planning and vehicle deployment. Current practice is to translate available OEM manufacturing costs (or cost estimates) into likely sale prices by using a markup factor. This study examines the state of the literature as it pertains to light-duty vehicle cost markup factors to understand the foundation of available markup factor formulations and to describe how variations in assumptions may impact those factors. The study examines and evaluates literature to observe trends, such as markup factor variance and efforts to devise variable markup factors. It finds that there is consensus for a markup factor of 2.0 for vehicle parts produced by "in-house" and a factor of 1.5 for parts that are outsourced. There is wide acknowledgement that these values are not indicative of any specific part, or manufacturer. Rather, they highlight that over time the market has shown that it will, on average, across a manufacturer's entire fleet, allow the OEMs to set their prices such that their return is consistent with the markup factors presented. Some vehicles will have higher markup factors and they will thus subsidize vehicles with lower markup factors.
Shifting agricultural practices to produce sustainable, low carbon intensity feedstocks for biofuel production
X. Liu, H. Kwon, D. Northrup, M. Wang
https://iopscience.iop.org/article/10.1088/1748-9326/ab794e/meta
http://greet.es.anl.gov/publication-shift_agr_for_low_c_feedstocks
The carbon intensity (CI) of biofuel's well-to-pump life cycle is calculated by life cycle analysis (LCA) to account for the energy/material inputs of the feedstock production and fuel conversion stages and the associated greenhouse gas (GHG) emissions during these stages. The LCA is used by the California Air Resources Board's Low Carbon Fuel Standard (LCFS) program to calculate CI and monetary credits are issued based on the difference between a given fuel's CI and a reference fuel's CI. Through the Tier 2 certification program under which individual fuel production facilities can submit their own CIs with their facility input data, the LCFS has driven innovative technologies to biofuel conversion facilities, resulting in substantial reductions in GHG emissions as compared to the baseline gasoline or diesel. A similar approach can be taken to allow feedstock petition in the LCFS so that lower-CI feedstock can be rewarded. Here we examined the potential for various agronomic practices to improve the GHG profiles of corn ethanol by performing feedstock-level CI analysis for the Midwestern United States. Our system boundary covers GHG emissions from the cradle-to-farm-gate activities (i.e. farm input manufacturing and feedstock production), along with the potential impacts of soil organic carbon change during feedstock production. We conducted scenario-based CI analysis of ethanol, coupled with regionalized inventory data, for various farming practices to manage corn fields, and identified key parameters affecting cradle-to-farm-gate GHG emissions. The results demonstrate large spatial variations in CI of ethanol due to farm input use and land management practices. In particular, adopting conservation tillage, reducing nitrogen fertilizer use, and implementing cover crops has the potential to reduce GHG emissions per unit corn produced when compared to a baseline scenario of corn–soybean rotation. This work shows a large potential emission offset opportunity by allowing feedstock producers a path to Tier 2 petitions that reward low-CI feedstocks and further reduce biofuels' CI. The prevalence of significant acreage that has not been optimized for CI suggests that policy changes that incentivize optimization of this parameter could provide significant additionality over current trends in farm efficiency and adoption of conservation practice.
Update of Emission Factors of Greenhouse Gases and Criteria Air Pollutants, and Generation Efficiencies of the U.S. Electricity Generation Sector
http://greet.es.anl.gov/publication-ele_2020
Environmental, Economic, and Scalability Consideration of Selected Biomass-Derived Blendstocks for Mixing-Controlled Compression Ignition (MCCI) Engines
P. Benavides, A. Bartling
http://greet.es.anl.gov/publication-bioblendstock_mcci
Presented in ICOSSE 2020. About the environmental, economic, and scalability considerations of selected biomass-derived blendstocks for mixing-controlled compression ignition (MCCI) engines using techno-economic analysis (TEA) and life-cycle analysis (LCA).
Life-cycle energy use and greenhouse gas emissions of palm fatty acid distillate derived renewable diesel
H. Xu, U.Lee, M. Wang
http://greet.es.anl.gov/publication-pfa_rd
This study aims to quantify life-cycle fossil energy use and greenhouse gas (GHG) emissions for palm fatty acid distillate (PFAD) derived renewable diesel (RD) taking into consideration different feedstock classifications that are applicable to PFAD (residue, byproduct, or coproduct), and incorporating updated data for key processes. Under the three classifications, the PFAD to RD pathway was modeled using the Greenhouse gases, Regulated Emissions, and Energy Use in Technologies (GREET®) model. PFAD-derived RD could reduce fossil energy consumption by 77%–88%, relative to petroleum diesel. GHG emissions are very sensitive to PFAD classification and coproduct handling methods. Considering the production of palm oil and PFAD and economic value, we maintain that PFAD should be treated as a byproduct in palm oil refineries. With this treatment, PFAD-derived RD could achieve 84% GHG emissions reductions, compared to the emissions of petroleum diesel. We also employed a substitution method to address the substitution of PFAD by other materials in the marketplace. Compared to coproduct allocation results, we found substituting PFAD by tallow, soy oil, barley, and canola oil results in lower GHG emissions. Due to high induced land-use change emissions associated with palm farming, if PFAD is treated as a coproduct with refined palm oil, PFAD-derived RD may not deliver GHG reductions. A sensitivity analysis identified key parameters such as palm fruit yield, oil extraction efficiency in oil mills, and energy use intensity for RD production affects LCA results significantly; future efforts to improve these parameters could result in further GHG reductions.
Life cycle energy use and greenhouse gas emissions of ammonia production from renewable resources and industrial by-products
X. Liu, A. Elgowainy, M. Wang
https://pubs.rsc.org/--/content/articlelanding/2020/gc/d0gc02301a/unauth#!divAbstract
http://greet.es.anl.gov/publication-lca_nh3_renew_indus
Conventionally, ammonia is produced from natural gas via steam methane reforming (SMR), water-gas shift reaction, and the Haber–Bosch process. The process uses fossil natural gas, which leads to 2.6 metric tons of life cycle greenhouse gas (GHG) emissions per metric ton of ammonia produced. With ammonia being the second most produced chemical in the world, its production accounts for approximately 2% of worldwide fossil energy use and generates over 420 million tons of CO2 annually. To reduce its carbon intensity, ammonia synthesis relying on renewable energy or utilizing by-products from industrial processes is of interest. We conduct a life cycle analysis of conventional and alternative ammonia production pathways by tracking energy use and emissions in all conversion stages, from the primary material and energy resources to the ammonia plant gates. Of all the alternative pathways, obtaining N2 from cryogenic distillation and H2 from low-temperature electrolysis using renewable electricity has the lowest cradle-to-plant-gate GHG emissions, representing a 91% decrease from the conventional SMR pathway.
Life cycle greenhouse gas emissions and energy use of polylactic acid, bio-derived polyethylene, and fossil-derived polyethylene
P. Benavides, U. Lee, O. Zarè-Mehrjerdi
http://greet.es.anl.gov/publication-pla_pe
Bioplastics recently have become an attractive, viable, and popular alternative to conventional petroleum-based plastics, with the hope that replacing fossil-derived plastics with renewable alternatives will reduce greenhouse gas (GHG) emissions and fossil energy consumption (FEC). The bioplastic industry is encouraging creative designs and enhanced properties such as biodegradability, which is considered a sustainable solution for waste plastic management. However, biodegradability also means that carbon in the product is emitted to the atmosphere as GHG emissions. In this paper, a life cycle analysis (LCA) of biodegradable polylactic acid (PLA) and bio-polyethylene (bio-PE) plastics was conducted to understand the environmental effects of these bioplastics from feedstock production to product end-of-life (EOL). In particular, emissions from biodegradability (EOL emissions) are accounted for. The results were compared to those of conventional fossil-based plastics such as high-density polyethylene (HDPE) and low-density polyethylene (LDPE). Results showed that the lowest GHG emissions (−1.0 and 1.7 kg CO2e per kg for bio-PE and PLA with no biodegradation, respectively) and FEC (29 and 46 MJ per kg of bio-PE and PLA, respectively) were achieved with bio-derived plastics, particularly bio-PE plastic. However, despite the benefits of biogenic carbon uptake, when landfill and composting emissions were considered for the PLA pathway, the life cycle emissions of PLA increase significantly, from 16% to 163% depending on the biodegradation condition, compared to the case where there is no degradation in the landfill. This study also contributed to understand the effects on the GHG emissions of biodegradability in landfill and composting scenarios, regional electricity mix, and plastics manufacturing technologies.
Lithium Pathway Updates and Additions in the GREET ® Model
J. Kelly, Q. Dai, O. Winjobi
http://greet.es.anl.gov/publication-li_update_2020
The purpose of this document is to provide an update to the structure of lithium production pathways within the GREET model. Specifically, this update will introduce pathways for lithium extracted from spodumene ore and converted into lithium carbonate (Li2CO3) and lithium hydroxide (LiOH). Within the GREET model, no numerical data will be provided for these ore-based pathways. The brine-based lithium pathways will be retained, but modifications to the calculation methods of some precursor materials will be integrated. However, these do not impact any current data for the lithium pathways presently in GREET. The impetus for this update is a forthcoming release of a lithium production pathways report that will provide the numerical basis to populate the new and updated pathways.
Sources of Propane Consumed in California
S. Backes, J. Beath, B. Sebastian, T. Hawkins
http://greet.es.anl.gov/publication-propane_ca
The objective of this study is to specify the sources of propane consumed in California. It answers the questions, where does the propane used in California come from and how was it produced? The results of this study provide comprehensive, transparent, and verifiable estimates, based on the 2018 market. The information provided in this report is suitable for use to assess the life cycle carbon intensity of propane used as a transportation fuel in California. As the 2009 Low Carbon Fuel Standard (LCFS) aims to reduce California's greenhouse gas (GHG) emissions and other smog-forming and toxic air pollutants, the appropriate designation of carbon intensity for propane as a transportation fuel is important for evaluating propane's potential to contribute to GHG goals and understandings in the context of various actions. This study focuses on estimating the shares of total propane consumed in the state of California produced from petroleum refineries, natural gas plants, and bituminous sands sources inside California and elsewhere.
Carbon Calculator for Land Use and Land Management Change from Biofuels Production (CCLUB) Manual (Rev. 6)
H. Kwon, X. Liu, J. Dunn, S. Mueller, M. Wander, M. Wang
http://greet.es.anl.gov/publication-cclub-manual-r6-2020
The Carbon Calculator for Land Use and Land Management Change from Biofuels Production (CCLUB) has been developed as an integral part of Argonne National Laboratory's Greenhouse Gases, Regulated Emissions, and Energy use in Technologies (GREET) model to analyze greenhouse gas emissions from land use change and land management change in the context of overall biofuel life-cycle analysis. This document discusses the revised version of CCLUB released September 30, 2020
Nickel Life Cycle Analysis Updates and Additions in the GREET Model
Q. Dai, J. Kelly
http://greet.es.anl.gov/publication-ni_2020
Update of Bill-of-Materials and Cathode chemistry addition for Lithium-ion Batteries in the GREET® Model
O. Winjobi, Q. Dai, J. Kelly
http://greet.es.anl.gov/publication-bom_lib_2020
The purpose of this document is to provide an update to the specific energy and bill-of-materials (BOMs) for the lithium-ion batteries (LIBs) for electric vehicles (EVs), including hybrid electric vehicle (HEVs), plug-in electric vehicle (PHEV), and battery electric vehicle (BEV) in GREET. An additional cathode chemistry, LiNi0.5Mn0.3Co0.2O2 (NMC532) is also included in the battery module for BEVs. The update is motivated by the changes in the specific energies and BOMs of LIBs as detailed in BatPaC 4.0 released in 2020.
Update of Vehicle Material Composition in the GREET® Model
O. Winjobi, J. Kelly
http://greet.es.anl.gov/publication-vmc_2020
This document provides an update to the material compositions for conventional Type 1 vehicles, including Cars, small Sport Utility Vehicles (SUVs), and Pickup Trucks (PUTs) in GREET. The vehicle body, powertrain, and chassis were updated based on the most recent aggregated data-set from A2Mac1 for internal combustion engine vehicles (ICEVs). The data-set is also used to update aspects of the hybrid electric vehicle (HEVs), plug-in electric vehicle (PHEV), battery electric vehicle (BEV), and fuel cell electric vehicle (FCEV).
User Guide for FD-CIC Tool 2020
X. Liu, H. Kwon, M. Wang
http://greet.es.anl.gov/publication-fd-cic-tool-2020-user-guide
M. Wang, A. Elgowainy, U. Lee, A. Bafana, P. Benavides, A. Burnham, H. Cai, Q. Dai, U. Gracida-Alvarez, T. Hawkins, P. Jaquez, J. Kelly, H. Kwon, Z. Lu, X. Liu, L. Ou, P. Sun, O. Winjobi, H. Xu, E. Yoo, G. Zaimes, G. Zang
The GREET® (Greenhouse gases, Regulated Emissions, and Energy use in Technologies) model has been developed by Argonne National Laboratory with the support of the U.S. Department of Energy (DOE). GREET is a life-cycle analysis (LCA) tool, structured to systematically examine the energy and environmental effects of a wide variety of transportation fuels and vehicle technologies in major transportation sectors (i.e., road, air, marine, and rail) and other end-use sectors, and energy systems. Argonne has expanded and updated the model in various sectors in GREET 2020, and this report provides a summary of the release.
Assessment of Potential Future Demands for Hydrogen in the United States
A. Elgowainy, M. Mintz, U. Lee, T. Stephens, P. Sun, K. Reddi, Y. Zhou, G. Zang, M. Ruth, P. Jadun, E. Connelly, R. Boardman
http://greet.es.anl.gov/publication-us_future_h2
H2@Scale is a U.S. Department of Energy (DOE) initiative that brings together stakeholders to advance the affordable production, transport, storage, and utilization of hydrogen (H2) as an energy carrier to increase revenue opportunities in multiple energy sectors. The focus of the current work is to characterize the growth potential of diverse hydrogen industries in the United States, given research and development (R&D) advancements in hydrogen technologies.
Refinery Products Volatile Organic Compounds Emissions Estimator (RP-VOC):User Manual and Technical Documentation
J. Beath, P. Vosmus, R. Kazanski, S. Backes, B. Sebastian, G. Zaimes, T. Hawkins
http://greet.es.anl.gov/publication-rp_voc_manual
The estimation of well-to-distributor volatile organic compound (VOC) emissions resulting from the extraction of crude oil in an oilfield, transportation to a crude oil terminal upstream of the refinery, operation of the refinery, and subsequent pipeline and product distribution has previously been approached as a top-down industry-wide average; RP-VOC performs its core calculations using a "from-the-ground-up" approach. By taking this approach, the tool results can be used for the supply network of a single refinery, or to generalize the average performance of all refineries.
Using waste CO2 from corn ethanol biorefineries for additional ethanol production: life‐cycle analysis
U. Lee, T. Hawkins, E. Yoo, M. Wang, Z. Huang, L. Tao
https://onlinelibrary.wiley.com/doi/full/10.1002/bbb.2175
http://greet.es.anl.gov/publication-waste_co2_to_etoh
Corn ethanol plants generate high‐purity carbon dioxide (CO2) while producing ethanol. If that CO2 could be converted into ethanol by carbon capture and utilization technologies it would be possible to increase ethanol production more than 37% without additional corn grain inputs. Gas fermentation processes use microbes to convert carbon‐containing gases into ethanol and so have the potential to be used with the CO2 from biorefineries for this purpose. However, as CO2 utilization technologies for converting thermodynamically stable CO2 are typically energy intensive, it is necessary to evaluate the related life‐cycle greenhouse gas (GHG) emissions (carbon intensities or CIs) to see whether there are actual emission reduction benefits. In this study, we evaluate the CIs of ethanol produced from high‐purity CO2 in corn ethanol plants by gas fermentation plus electrochemical reduction. Our analysis shows that the sources of electricity and hydrogen are key drivers of CO2‐based ethanol's GHG emissions. With wind electricity, the design cases show the potential of near‐zero CI ethanol (1.1 g CO2e/MJ), but that can increase to up to 331–531 g CO2e/MJ when today's U.S. Midwest electricity mix is used. To avoid the renewable electricity intermittency issue, we considered a power purchase agreement option using wind electricity 40% of the time and using the regional mix for the rest, which provides a 42% GHG emission reduction from the CI of gasoline.
Well-to-Wheels Analysis of Zero-Emission Plug-In Battery Electric Vehicle Technology for Medium- and Heavy-Duty Trucks
X. Liu, A. Elgowainy, R. Vijayagopa, M. Wang
https://pubs.acs.org/doi/10.1021/acs.est.0c02931
http://greet.es.anl.gov/publication-wtw_bev_mhd_trucks
Conventional diesel medium- and heavy-duty vehicles (MHDVs) create large amount of air emissions. With the advancement in technology and reduction in the cost of batteries, plug-in battery electric vehicles (BEVs) are increasingly attractive options for improving energy efficiency and reducing air emissions of MHDVs. In this paper, we compared the well-to-wheels (WTW) greenhouse gases (GHGs) and criteria air pollutant emissions of MHD BEVs with their conventional diesel counterparts across weight classes and vocations. We expanded the Greenhouse gases, Regulated Emissions, and Energy use in Technologies (GREET) model to conduct the WTW analysis of MHDVs. The fuel economy for a wide range of MHDV weight classes and vocations, over various driving cycles, was evaluated using a high-fidelity vehicle dynamic simulation software (Autonomie). The environmental impacts of MHD BEVs are sensitive to the source of electricity used to recharge their batteries. The WTW results show that MHD BEVs significantly improve environmental sustainability of MHDVs by providing deep reductions in WTW GHGs, nitrogen oxides, volatile organic compounds, and carbon monoxide emissions, compared to conventional diesel counterparts. Increasing shares of renewable and natural gas technologies in future national and regional electricity generation are expected to reduce WTW particulate matters and sulfur oxide emissions for further improvement of the environmental performance of MHD BEVs.
Nuclear-Supported Electrification of the Transportation Sector
X. Liu, A. Bafana, P. Sun, A. Elgowainy
https://www.sciencedirect.com/science/article/pii/B9780128197257001677?via%3Dihub
http://greet.es.anl.gov/publication-nuclear_ele_trans
Electrification of the transportation sector is of increasing interest due to its zero tailpipe emissions. The leading electrification technologies are plug-in battery electric vehicles (BEV) that uses grid electricity directly, and fuel cell electric vehicles (FCEV) that uses hydrogen, which can be produced from various energy and feedstock sources. Nuclear electricity can play an important role in the electrification and decarbonization of various transportation applications. This chapter assesses the environmental impacts of adopting BEVs and FCEVs using nuclear power and other energy sources and compares with the emissions from conventional gasoline internal combustion engine vehicles on a well-to-wheels basis.
Techno-Economic Analysis (TEA) Factsheet
ANL ES Division
http://greet.es.anl.gov/publication-tea_factsheet
Effects of forest harvesting and biomass removal on soil carbon and nitrogen: Two complementary meta-analyses
J James, D Page-Dumroese, M Busse, B Palik, J Zhang, B Eaton, R. Slesak, J. Tirocke, H. Kwon
https://doi.org/10.1016/j.foreco.2021.118935
http://greet.es.anl.gov/publication-soil_cn
Forest residues and logging slash from pre-commercial forest thinning and regeneration harvests are a potential feedstock for bioenergy production but there has been a concern about the impact of residue removal on forest soil C and N. This study aimed to address such by conducting two meta-analyses using the data available from published literature and an independent dataset compiled from the North American Long-Term Soil Productivity (LTSP) study. For the meta-analysis using literature, we categorized forest harvesting and biomass removal into i) no harvest control, ii) bole-only (BO, partial or clearcut) regular harvests, iii) BO with partial removal of logging slash and/or O horizon (BO+Removal), iv) whole tree harvests (WTH), and v) WTH with slash and O horizon removal (WTH+Removal). Accordingly, we compiled soil C and N data and key statistics (e.g., standard deviation) from 142 scientific articles published since 1979. We compared the results from this meta-analysis with data from 22 installations of the LTSP study where three levels of organic matter removal - BO, WTH, and WTH plus forest floor (+FF, O horizon) removal - as well as an additional vegetation control (+VC) were measured for two decades in either completely randomized or randomized block design. In the literature meta-analysis, BO+Removal (-19.2%), WTH (-15.4%) and WTH+Removal (-24.9%) contained significantly less soil C than no-harvest controls across combined soil depths, while BO had no difference. Within individual mineral soil horizons, only BO+Removal and WTH+Removal treatments contained significantly less carbon than controls. There was a high degree of heterogeneity in treatment response between studies in the literature. The analyses from the LTSP dataset showed no significant difference in combined soil depths for WTH or WTH+VC relative to BO harvest, but there was significantly less soil C in BO+VC (-3.6%), WTH+FF (-8.5%) and WTH+FF+VC (-15.3%). These treatment effects declined over time since harvest, particularly the most intensive treatments. Soil N results largely mirrored soil C in both meta-analyses with smaller estimated effects for most treatments at equivalent depths (except for WTH+Removal and WTH+FF+VC, which remain about the same). There were no significant differences in soil N for combined soil depths between WTH and no-harvest control (in the literature analysis) or BO harvest (for both analyses). Since the most severe losses of soil C and N involved FF removal, WTH that accounts for modest removals (<80%) of harvesting residues may provide a sustainable source of biomass for bioenergy production without additional soil impacts compared to BO harvesting practices.
Update of Platinum Production and Addition of Platinum-Group Metals (PGMs) to GREET® 2021
K. Kingsbury, P. Benavides
http://greet.es.anl.gov/publication-pgm_2021
This technical memo describes updates to the Greenhouse gases, Regulated Emissions, and Energy use in Technologies (GREET®) model regarding the production of the platinum-group metals (PGMs). The energy and water consumption of PGM production is updated from 2014 values that were provided in an Argonne report by Benavides et al. (2015) to new data representing the average energy and water consumption from 2015 to 2019
Life Cycle Inventories for Palladium on Niobium Phosphate (Pd/NbOPO4) and Zirconium Oxide (ZrO2) Catalysts
http://greet.es.anl.gov/publication-pdnbopo4_zro2
This report examines the consumption of material and energy inputs throughout the life cycle of the Palladium on Niobium Phosphate (Pd/NbOPO4) and Zirconium Oxide (ZrO2) catalysts. Both catalysts have been used successfully in biofuel production, so the material and energy flows for the new catalysts and associated materials will be relevant to future biofuel LCAs. We describe the supply chain, life cycle inventory collection, and cradle-to-gate life cycle analysis results for the two catalysts and their associated materials in the following technical report. Material and energy inputs were collected from a variety of sources including scientific literature, technical reports from Argonne and other national laboratories, sustainability reports from mining and chemical companies, information already in the GREET model, and direct correspondence with experts in the field. In the report, we also identify and discuss the primary contributors to each catalyst's environmental burden, and we provide suggestions for making improvements in the catalysts' supply chains
Developing county-level data of nitrogen fertilizer and manure inputs for corn production in the United States
Y Xia, H Kwon, M Wander
https://doi.org/10.1016/j.jclepro.2021.126957
http://greet.es.anl.gov/publication-county_corn_inputs
Spatially-explicit data describing commercial nitrogen (N) fertilizer and animal manure inputs are needed to inform modeling and life cycle analysis of agricultural impacts associated with corn production. The currently available N datasets based on farm surveys and sales for the Conterminous U.S. are inappropriate for corn-based modeling at fine resolutions because they are either too coarse in scale or are not corn-specific. This work developed county-level N input data for corn production by harmonizing multiple U.S. datasets using two data fusion approaches. A top-down area-based approach allocates N fertilizer inputs into corn producing areas by combining state-level crop-specific N fertilizer application rates and percentage of area receiving N fertilizer with the county-level proportion of crop-specific planted area. Similarly, county-level manure N rates are calculated based on county-level corn planted area and livestock populations coupled with state-level application data. An alternative approach derives N needs from corn yields, crop rotations, and soil characteristics before N surplus is estimated by subtracting N needs from N rates. Nationally, the weighted averages of corn N inputs (188 kg N ha−1) based on corn planted area exceeded N needs (128 kg N ha−1) by 60 kg N ha−1 with N surplus found in 80% of all U.S. corn producing counties. Results distinguished regions of high (Midwest), moderate (Northern Plains), and low (Southeast and Northwest) N application rates and surpluses. Estimates for Western states had the greatest variability and uncertainty associated with the frequency of N rate outliers where corn production is low. The estimated N inputs for major corn producing areas generally aligned with source datasets, while further evaluation is needed for manure application rates using independent sources. This work shared the first spatially-explicit datasets for U.S. corn fertilizer and manure inputs and N needs together with methods for evaluation. Steps needed to expand access and coverage of detailed N data were identified to improve assessments of agricultural and environmental impacts.
Retrospective analysis of the U.S. corn ethanol industry for 2005–2019: implications for greenhouse gas emission reductions
U. Lee, H. Kwon, M. Wu, M. Wang
https://onlinelibrary.wiley.com/doi/10.1002/bbb.2225
http://greet.es.anl.gov/publication-us_corn_ethanol_2005_2019
Since 2000, corn ethanol production in the USA has increased significantly – from 1.6 to 15 billion gallons (6.1 to 57 billion liters) – due to supportive biofuel policies. In this study, we conduct a retrospective analysis of the changes in US corn ethanol greenhouse gas emission intensity, sometimes known as carbon intensity (CI), over the 15 years from 2005 to 2019. Our analysis shows a significant decrease in CI: from 58 to 45 gCO2e/MJ of corn ethanol (a 23% reduction). This is due to several factors. Corn grain yield has increased continuously, reaching 168 bushels/acre (10.5 metric tons/ha, a 15% increase) while fertilizer inputs per acre have remained constant, resulting in decreased intensities of fertilizer inputs (e.g., 7% and 18% reduction in nitrogen and potash use per bushel of corn grain harvested, respectively). A 6.5% increase in ethanol yield, from 2.70 to 2.86 gal/bushel corn (0.402 to 0.427 L kg−1 corn), and a 24% reduction in ethanol plant energy use, from 32 000 to 25 000 Btu/gal ethanol (9.0 to 6.9 MJ L−1 ethanol) also helped reduce the CI. The total GHG emission reduction benefits through the reduction in the CI and increased ethanol production volume are estimated at 140 million metric tons (MMT) from 2005 to 2019 in the ethanol industry. Displacement of petroleum gasoline by corn ethanol in the transportation fuel market resulted in a total GHG emission reduction benefit of 544 MMT CO2e during the period 2005 to 2019.
Synthetic Methanol/Fischer–Tropsch Fuel Production Capacity, Cost, and Carbon Intensity Utilizing CO2 from Industrial and Power Plants in the United States
G. Zang, P. Sun, E. Yoo, A. Elgowainy, A. Bafana, U. Lee, M. Wang, S. Supekar
https://pubs.acs.org/doi/full/10.1021/acs.est.0c08674
http://greet.es.anl.gov/publication-synthetic_meoh_ft_fuel
Captured CO2 is a potential feedstock to produce fuel/chemicals using renewable electricity as the energy source. We explored resource availability and synergies by region in the United States and conducted cost and environmental analysis to identify unique opportunities in each region to inform possible regional and national actions for carbon capture and utilization development. This study estimated production cost of synthetic methanol and Fischer–Tropsch (FT) fuels by using CO2 captured from the waste streams emitted from six industrial [ethanol, ammonia, natural gas (NG) processing, hydrogen, cement, and iron/steel production plants] and two power generation (coal and NG) processes across the United States. The results showed that a total of 1594 million metric ton per year of waste CO2 can be captured and converted into 85 and 319 billion gallons of FT fuels and methanol, respectively. FT fuels can potentially substitute for 36% of the total petroleum fuels used in the transportation sector in 2018. Technoeconomic analysis shows that the minimum selling prices for synthetic FT fuels and methanol are 1.8–2.8 times the price of petroleum fuel/chemicals, but the total CO2 reduction potential is 935–1777 MMT/year.
Response to "how robust are reductions in modeled estimates from GTAP-BIO of the indirect land use change induced by conventional biofuels?"
F Taheripour, S Mueller, H Kwon
http://greet.es.anl.gov/publication-response_robust_iluc_biofuel
Malins et al. (2020) recently published "How robust are reductions in modeled estimates from GTAP-BIO of the indirect land use change induced by conventional biofuels?", provided their narrative from the model improvements in GTAP-BIO over time, made several critical points regarding this model, and argued that the implemented improvements in this model tended to decrease Induce Land Use Changes (ILUC) emissions. They also provided several critical points regarding the Carbon Calculator for Land Use Change from Biofuels Production (CCLUB) emissions model. In this response to Malins et al. we address these critiques point-by-point by providing our detailed responses to key issues: 1) the GTAP-BIO model and its improvements over time; 2) the inclusion of cropland pasture in the model; 3) the observed land use changes in the US that have been the bases for improvements in GTAP-BIO model, 4) the time trends in corn price and yield to challenge the concept of the yield to price response; 5) some sources of land intensification in crop production; 6) the FAO notifications with respect to the comparison between harvested area and arable land; and 7) the GTAP-BIO results for multiple cropping. We also provided responses to Malins et al. critical points regarding the CCLUB emissions model. We hope that this response letter will open more constructive discussion among the LUC modeling community to remain focused on the big picture regarding agriculture's role as a very effective GHG mitigation tool that can shape the new policies to govern the production and consumption of biofuels.
Biofuel Options for Marine Applications: Technoeconomic and Life-Cycle Analyses
E. Tan, T. Hawkins, U. Lee, L. Tao, P. Meyer, M. Wang, T. Thompson
https://pubs.acs.org/doi/abs/10.1021/acs.est.0c06141
http://greet.es.anl.gov/publication-marine_2019
This study performed technoeconomic and life-cycle analyses to assess the economic feasibility and emission benefits and tradeoffs of various biofuel production pathways as an alternative to conventional marine fuels. We analyzed production pathways for (1) Fischer–Tropsch diesel from biomass and cofeeding biomass with natural gas or coal, (2) renewable diesel via hydroprocessed esters and fatty acids from yellow grease and cofeeding yellow grease with heavy oil, and (3) bio-oil via fast pyrolysis of low-ash woody feedstock. We also developed a new version of the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) marine fuel module for the estimation of life-cycle greenhouse gas (GHG) and criteria air pollutant (CAP) emissions of conventional and biobased marine fuels. The alternative fuels considered have a minimum fuel selling price between 2.36 and 4.58 $/heavy fuel oil gallon equivalent (HFOGE), and all exhibit improved life-cycle GHG emissions compared to heavy fuel oil (HFO), with reductions ranging from 40 to 93%. The alternative fuels also exhibit reductions in sulfur oxides and particulate matter emissions. Additionally, when compared with marine gas oil and liquified natural gas, they perform favorably across most emission categories except for cases where carbon and sulfur emissions are increased by the cofed fossil feedstocks. The pyrolysis bio-oil offers the most promising marginal CO2 abatement cost at less than $100/tonne CO2e for HFO prices >$1.09/HFOGE followed by Fischer–Tropsch diesel from biomass and natural gas pathways, which fall below $100/tonne CO2e for HFO prices >$2.25/HFOGE. Pathways that cofeed fossil feedstocks with biomass do not perform as well for marginal CO2 abatement cost, particularly at low HFO prices. This study indicates that biofuels could be a cost-effective means of reducing GHG, sulfur oxide, and particulate matter emissions from the maritime shipping industry and that cofeeding biomass with natural gas could be a practical approach to smooth a transition to biofuels by reducing alternative fuel costs while still lowering GHG emissions, although marginal CO2 abatement costs are less favorable for the fossil cofeed pathways.
Life cycle analysis of renewable natural gas and lactic acid production from waste feedstocks
U. Lee, A. Bhatt, T. Hawkins, L. Tao, P. Benavides, M. Wang
http://greet.es.anl.gov/publication-waste_to_rng_la
Producing fuels and chemicals from waste is considered economically favorable, due to low feedstock cost, and environmentally favorable, due to avoided emissions from conventional waste management practices. In this study, we evaluate the life cycle greenhouse gas (GHG) emission reduction benefits of renewable natural gas (RNG) and lactic acid (LA) production from four types of wet waste feedstocks (wastewater sludge, food waste, swine manure, and fats, oil, and grease [FOG]) via anaerobic digestion (AD) and LA fermentation, respectively. RNG can be used as an alternative to fossil natural gas, while LA from waste feedstocks can displace conventional LA production pathways (mainly from corn via fermentation). Providing comprehensive life cycle GHG emissions of the combinations of waste feedstocks and products through different routes helps identify the GHG hotspots and show where emissions savings come from. The results show that the carbon intensities (CIs) of waste-derived RNG and LA are much lower than those of their counterparts. We estimated the life cycle GHG emissions for RNG to be between −146 and 27 g carbon dioxide equivalent (CO2e)/MJ, much lower than the CI of fossil fuels. Waste-derived LA pathways also show substantially lower CIs, ranging from −4.2 to −1.4 kgCO2e/kg LA, compared to the CIs of LA from corn and corn stover (1.2 and 0.3 kgCO2e/kg LA, respectively). We will also discuss that the low CIs of waste-derived products can come from low yields leading to high emission credits. Thus, life cycle analysis results presented per weight of treated waste can be used to support decisions about which waste feedstocks and products are to be used for sustainable waste valorization. In addition, we found that monetary emission reduction credits can play an important role in driving waste valorization.
Varied farm-level carbon intensities of corn feedstock help reduce corn ethanol greenhouse gas emissions
https://iopscience.iop.org/article/10.1088/1748-9326/ac018f
http://greet.es.anl.gov/publication-ci_corn_feedstock
A reduction in the overall carbon intensity (CI) of a crop-based biofuel can be achieved by cutting down the CI of the biofuel's feedstock, which in turn correlates significantly to agricultural management practices. Proposals are being made to incentivize low-carbon biofuel feedstocks under U.S. fuel regulatory programs to promote sustainable farming practices by individual farms. For such an incentive scheme to function properly, robust data collection and verification are needed at the farm level. This study presents our collaboration with U.S. private sector companies to collect and verify the corn production data necessary for feedstock-specific CI calculation at the farm level, through a carefully designed questionnaire, to demonstrate the practicality and feasibility of data collection at scale. We surveyed 71 farms that produced 0.2 million metric tons of corn grain in 2018 in a Midwestern U.S. state to obtain information on key parameters affecting corn ethanol feedstock CI, such as grain yields, fertilizer/chemical application rates, and agronomic practices. Feedstock-specific CI was calculated in the unit of grams (g) CO2 equivalent (CO2e) of greenhouse gases per kilogram (kg) of corn produced. Results showed large CI variations—from 119 to 407 g CO2e kg−1 of corn—due to the farm-level inventory, while the production-weighted average CI for all surveyed farms was 210 g CO2e kg−1, comparable to the national average CI of 204 g CO2e kg−1. The nitrogen fertilizer type applied and rate were identified as key factors contributing most to CI variations at the farm level. The estimated N2O emissions from fertilizer and biomass nitrogen inputs to soil accounted for 51% of the overall farm-level CI and therefore need to be better monitored at farm level with high resolution. We concluded that this feedstock-specific, farm-level CI evaluation has the potential to be used to incentivize low-carbon feedstock for biofuel production.
Energy, greenhouse gas, and water life cycle analysis of lithium carbonate and lithium hydroxide monohydrate from brine and ore resources and their use in lithium ion battery cathodes and lithium ion batteries
J. Kelly, M. Wang, Q. Dai, O. Winjobi
http://greet.es.anl.gov/publication-lca_li2co3_liohh2o
Life cycle analyses (LCAs) were conducted for battery-grade lithium carbonate (Li2CO3) and lithium hydroxide monohydrate (LiOH•H2O) produced from Chilean brines (Salar de Atacama) and Australian spodumene ores. The LCA was also extended beyond the production of Li2CO3 and LiOH•H2O to include battery cathode materials as well as full automotive traction batteries to observe the effect that the lithium production pathways had on these end products. The LCA here covers material, water, and energy flows associated with lithium acquisition; lithium concentration; production of lithium chemicals, battery cathode powders, and batteries; and associated transportation activities along the supply chain. Based on battery cathode material, the difference in lithium source represents a difference of up to 20% for NMC811 cathode greenhouse gases (GHGs) and up to 45% for NMC622 cathode GHGs. For full batteries, this represents a difference of up to 9% for NMC811 batteries and 20% for NMC622 batteries. Production of Li2CO3 from brine-based resources had less life cycle GHG emissions and freshwater consumption per tonne of Li2CO3 than Li2CO3 from ore-based resources. And LiOH•H2O produced from brine-based lithium also had less life cycle GHG emissions and freshwater consumption per tonne of LiOH•H2O than LiOH•H2O from ore-based resources.
Challenges and opportunities for alternative fuels in the maritime sector
A. Foretich, G. Zaimes, T. Hawkins, E. Newes
https://www.sciencedirect.com/science/article/pii/S2666822X21000241?via%3Dihub
http://greet.es.anl.gov/publication-alt_maritime_fuel
Amidst a period of historic transformation, the marine shipping sector faces uncertainty regarding its ability to reliably fuel while remaining compliant with new international environmental regulations and targets. Increasingly stringent environmental standards, and heightened regulatory focus on maritime decarbonization are driving infrastructural and technical development for alternative fuels and mixtures, engine concepts, and operating practices. However, the transition to alternative fueling is highly complex and requires both a global outlook that spans diverse stakeholder demographics and coordination with multiple actors across the value chain. To aid stakeholders involved in decision making and research related to the transition, a scoping study was conducted with the goal of outlining the barriers, uncertainties, and possibilities in the short and long term for the transition. Synthesis of these results provides strategic decision support, technical direction, and a set of R&D priorities for maritime stakeholders and the scientific community.
Greenhouse gas mitigation strategies and opportunities for agriculture
H. Kwon, X. Liu, H. Xu, M. Wang
https://doi.org/10.1002/agj2.20844
http://greet.es.anl.gov/publication-agri_ghg_mitigation
To cope with increasing demands for food, feed, and energy along with environmental challenges due to climate change, the agricultural sector has a unique opportunity to meet sustainable development goals set by the United Nations through innovative and regenerative agriculture practices that enhance agricultural productivity, ecosystem services, and human well-being simultaneously. Among many sustainability metrics to measure agriculture's impacts on sustainability and contribution to its improvements, we focus on the greenhouse gas (GHG) emissions from the agricultural sector as a key environmental indicator to assess several GHG mitigation practices from the perspective of life-cycle analysis applied to agriculture. We first analyze the key factors contributing to farming GHG emissions and then identify a range of GHG mitigation strategies, such as optimizing farm fertilizer/chemical inputs, manufacturing low-carbon fertilizer/chemical, reducing on-farm energy/fuel consumption, and increasing soil carbon stocks. Furthermore, we elaborate on how these strategies can be successfully implemented to different scales of farming through policies and incentives and better quantification and verification schemes for effective policies and incentives. Finally, we present the holistic evaluation of agricultural GHG emissions in terms of landscape management approaches and provide ecosystem services to address social and economic issues.
CORSIA: The first internationally adopted approach to calculate life-cycle GHG emissions for aviation fuels
M. Prussi, U. Lee, M. Wang, R. Malina, H. Valin, F. Taheripour, C. Velarde, M. Staples, L. Lonza, J. Hileman
http://greet.es.anl.gov/publication-corsia_ghg_aviation
The aviation sector has grown at a significant pace in recent years, and despite improvements in aircraft efficiency, the sector's impact on climate change is a growing concern. To address this concern, the International Civil Aviation Organization (ICAO) established the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) to help reduce aviation greenhouse gas (GHG) emissions. This paper presents a methodology agreed by the 193 ICAO member states to evaluate the life-cycle GHG emissions of sustainable aviation fuels (SAFs), in the CORSIA system. The core life-cycle assessment and induced land use change values of SAFs are presented to determine the GHG savings of certified pathways. The paper aims to present that a number of SAFs can yield significant life-cycle emission reductions compared to petroleum-derived jet fuel. This implies the potentially major role of SAFs in reducing aviation's carbon footprint.
Environmental Assessment of Alternative Fuels for Maritime Shipping
G Zaimes, J. Stuhr, E. Tan, K. Ramasamy, J. Askander, M. Kass, B. Kaul, T. Hawkins
http://greet.es.anl.gov/publication-alt_maritime_fuel_issst2021
Maritime shipping is undergoing a historic transformation period, catalyzed by recently promulgated restrictions on marine fuel sulfur content and a heightened regulatory focus on maritime decarbonization. The International Maritime Organization (IMO), the governing body of international shipping, has set aggressive targets aimed at reducing the carbon intensity of marine vessels, with an overall goal of 50% reduction in greenhouse gas emissions (GHG) from international shipping by 2050, relative to 2008 levels, and pursing efforts to phase out GHG emissions by the end of this century. In 2020, IMO set new regulations that restricted marine fuel sulfur content to 0.5% by weight, and issued a carriage ban on all non-compliant fuel. These regulations are reshaping the marine sector's energy landscape and driving the deployment of low-carbon and low-sulfur alternative fuels for marine transport. Among alternatives, biofuels are a promising option due to their low sulfur content, high energy density, compatibility with existing fuel infrastructure, and low carbon intensity. Holistic environmental systems analysis is critical for quantifying the broad-based environmental impacts of alternative fuels for marine applications and their capacity to meet long-term IMO GHG reduction targets. Thus, it is essential for guiding the sustainable development of the maritime sector. In this work, life cycle assessment (LCA) is performed to quantify the environmental performance of several novel marine biofuels systems including: (1) hydrothermal liquefaction (HTL) biocrude from waste sludge, (2) catalytic fast pyrolysis bio-oil, (3) biogas-to-liquids via Fischer Tropsch, (4) renewable fuels derived from the heavy cut of the aviation biofuel pool, and (5) lignin ethanol oil (LEO). These systems are conceptually appealing in the context of marine applications due to their capacity to produce minimally processed fuels (e.g., HTL biocrude, bio-oil). They can be blended with existing maritime fuels or further upgraded to be fungible with existing marine infrastructure and vessels. In this work, Argonne's Greenhouse Gases, Regulated Emissions, and Energy Use in Technology (GREET) model is used to characterize the life cycle environmental impacts of marine biofuels across multiple environmental metrics and benchmark the results against conventional Heavy Fuel Oil (HFO) as well as leading alternative marine fuels. LCA results are also coupled with Argonne's Maritime AGE model and used to track the life cycle environmental impacts of alternative marine fuel deployment at scale, based on projected global maritime fuel consumption reported in IEA's Sustainable Development Scenario for international shipping. This 'macro-level' perspective is complementary to traditional LCA results which are presented on a per unit energy basis. Preliminary LCA results indicate that biofuels can achieve up to 86% reduction in life cycle GHG emissions relative to HFO, and thus show technical merit for meeting IMO's long-term GHG reduction targets. Moreover, biofuels demonstrate reduced life cycle sulfur oxide emissions relative to HFO but exhibit several environmental tradeoffs such as higher water-footprint. Synthesis of these results provides a broad-based understanding of the environmental benefits and challenges of alternative fuels for maritime shipping and technical direction to guide research and development in next-generation marine fuels.
H. Cai, L. Ou, M. Wang, R. Davis, A. Dutta, K. Harris, M. Wiatrowski, E. Tan, A. Bartling, B. Klein, D. Hartley, Y. Lin, M. Roni, D. Thompson, L. Snowden-swan, Y. Zhu
http://greet.es.anl.gov/publication-2020_update_renewable_hc_fuel
The Department of Energy's (DOE) Bioenergy Technologies Office (BETO) aims to develop and deploy technologies to transform renewable biomass resources into commercially viable, high-performance biofuels, bioproducts, and biopower through public and private partnerships (U.S. Department of Energy, 2016). BETO and its national laboratory teams conduct in-depth techno-economic assessments (TEA) of biomass feedstock supply and logistics and conversion technologies to produce biofuels. There are two general types of TEAs: A design case outlines a target case (future projection) for a particular biofuel pathway. It enables identification of data gaps and research and development needs, and provides goals and benchmarks against which technology progress is assessed. A state of technology (SOT) analysis assesses progress within and across relevant technology areas based on actual results at current experimental scales relative to technical targets and cost goals from design cases, and includes technical, economic, and environmental criteria as available.
Building Life-Cycle Analysis with the GREET Building Module: A User Guide
H. Cai, T. Sykora, M. Wang
http://greet.es.anl.gov/publication-greet_building_guide_2021
This User Guide provides instructions about how to conduct both the building material-level LCA and whole building LCA with the GREET Building Module. We have developed the GREET Building Module on the GREET Excel platform to leverage extensive background data available in GREET1, GREET2, and those newly generated within the Module. All the background data are fully accessible, editable, and expandable to maintain transparency, consistency, and capability to address different building systems that encompass individual building materials, components, technology solutions, as well as whole buildings and building designs.
Updated Natural Gas Pathways in GREET 2021
Argonne National Laboratory researchers have been analyzing the environmental impacts of natural gas (NG) production and use for more than 20 years. With the rapid development of shale gas production in the past few years, significant efforts have been made to examine various stages of natural gas pathways to estimate their life-cycle impacts. In GREET 2021, we changed the default CH4 emissions to be based on a hybrid bottom-up and top-down approach.
MOVES3 Vehicle Operation Emission Factors
http://greet.es.anl.gov/publication-update_moves3
Vehicle operation air pollutant emission factors from gasoline and diesel vehicles are needed to construct baseline emission scenarios for well-to-wheels (WTW) analyses of both conventional and advanced vehicle technologies. Air pollutant emission factors vary over time with advances in engine technologies, changes in fuel specification regulations, deterioration due to vehicle age and mileage accumulation, implementation of tighter on-road emission controls such as inspection and maintenance (I/M) programs, and adoption of advanced emission control technologies, such as second-generation onboard diagnostics (OBD II), selective catalytic reduction, diesel particulate filters, and diesel oxidation catalysts. Therefore, up-to-date emission factors operations that reflect the latest vehicle technologies and emission control regulations are needed to understand pump-to-wheels emissions and to evaluate emission reduction potentials of alternative vehicle technologies. GREET has historically used Unites States Environmental Protection Agency (EPA) modeling, beginning with MOBILE and then the Motor Vehicle Emission Simulator (MOVES), to estimate vehicle operation air pollutant emission factors of gasoline and diesel vehicles (Wang, 1999; Brinkman et al., 2005; Cai et al. 2013; Cai et al., 2015). Cai et al. (2013) documents emission factors from the first MOVES model, MOVES2010, while Cai et al. (2015) documents the second version MOVES2014 with a focus on trucks and buses. This document presents model year (MY)-based air pollutant emission factors from vehicle operation activities for light-duty, medium-duty, and heavy-duty vehicles using gasoline and diesel fuels. The data was generated using latest version of EPA's mobile source emission modeling, MOVES3, and implemented into the GREET 2021 model (EPA, 2021).
Building Life-Cycle Analysis with the GREET Building Module: Methodology, Data, and Case Studies
H. Cai, X. Wang, J. Kelly, M. Wang
http://greet.es.anl.gov/publication-greet_building_method_2021
To holistically address building sustainability, Argonne National Laboratory has expanded its Greenhouse gases, Regulated Emissions, and Energy use in Technologies (GREET) life-cycle model with a new GREET Building Module. This report documents life-cycle analysis (LCA) methodology and foreground data that Argonne National Laboratory compiles and develops to address embodied greenhouse gas (GHG) emissions and energy impacts of a wide range of envelope and structural building materials for new construction and retrofits. The methodology and data form the backbone of the GREET Building Module. This research effort focuses on developing consistent LCA methodology that conforms to building LCA standards such as the EN 15978 to address embodied GHG emissions and energy impacts of building materials/technologies. We document detailed foreground data for selected building materials and building components that are common for building construction. To test the LCA methodology and the GREET Building Module, this report includes case studies of insulation materials and wall panels for residential building retrofit. We have developed a separate document as a User Guide for understanding and applying the GREET Building Module to conduct detailed, process-level LCA of embodied carbon and energy impacts of emerging building materials and technology solutions that of interest to the Building Technologies Office (BTO) of the US Department of Energy, researchers, and industry stakeholders.
Feedstock Carbon Intensity Calculator (FD-CIC) - Users' Manual and Technical Documentation
The carbon intensities (CIs) of biofuels are determined with the life cycle analysis (LCA) technique, which accounts for the energy/material uses and emissions during the complete supply chain of a biofuel including feedstock production and fuel conversion stages. Regulatory agencies such as California Air Resources Board (CARB) adopts LCA to calculate biofuel CIs. The Low Carbon Fuel Standard (LCFS) program developed by CARB allows individual biofuel conversion facilities to submit their own biofuel CIs with their facility input data and incentivizes the reduction in the CI specific to that particular facility compared to a reference fuel's CI (Liu, Kwon, et al., 2020). Such an incentive program has driven innovations in biorefineries to reduce their greenhouse gas (GHG) emissions by linking the plant's revenue directly to its CI score through LCFS credit trading. Besides biofuel conversion stage, different farming practices for feedstock growth can result in significant CI variations for feedstocks, thus for biofuels. To provide evidence-based research findings, the U.S. Department of Energy's Advanced Research Projects Agency–Energy (ARPA-E) has supported the Systems Assessment Center of the Energy Systems Division at Argonne National Laboratory to examine CI variations of different farming practices to grow agricultural crops for biofuel production. Meanwhile, the ARPA-E has launched the Systems for Monitoring and Analytics for Renewable Transportation Fuels from Agricultural Resources and Management (SMARTFARM) program to develop technologies and data platforms that enable an accurate measurement of key farming parameters that can help robust accounting of the GHG benefits of sustainable, low-carbon agronomic practices at farm level. A transparent and easy-to-use tool for feedstock-specific, farm-level CI calculation of feedstocks is especially helpful. With the ARPA-E support, we have developed a tool - the Feedstock Carbon Intensity Calculator (FD-CIC). The first version of FD-CIC was released with the GREET® model in 2020 (Wang et al., 2020) so that corn feedstock producers can use this publicly available tool (https://greet.es.anl.gov/tool_fd_cic) to quantify corn grain CIs with farm-level input data and management practices. In the 2021 version, we expand the tool's capabilities by including additional feedstocks such as soybeans, sorghum, and rice. Similar to corn, it calculates the farm-level CI for these feedstocks by allowing user-defined farm-level farming inputs and incorporating the GHG emission intensities of these inputs from GREET (in particular, GREET1, the fuel cycle model of GREET).
Update of the Manganese pathway in GREET® 2021
http://greet.es.anl.gov/publication-mn_update_2021
This memo documents updates in the GREET® model for the manganese pathway.
Vehicle-Cycle Inventory for Medium- and Heavy-Duty Vehicles
R. Iyer, J. Kelly
http://greet.es.anl.gov/publication-mhdv_vc
This report documents the new inventory incorporated in the GREET® model for vehicle-cycle of medium-duty and heavy-duty vehicles.
Update of the Carbon Fiber pathway in GREET 2021
http://greet.es.anl.gov/publication-carbon_fiber_2021_update
This memo documents updates in the GREET® model for the carbon fiber pathway and the weight-ratio of constituents (resin and fiber) in carbon fiber-reinforced plastic.
M. Wang, A. Elgowainy, U. Lee, A. Bafana, S. Banerjee, P. Benavides, P. Bobba, A. Burnham, H. Cai, U. Gracida-Alvarez, T. Hawkins, R. Iyer, J. Kelly, T. Kim, K. Kingsbury, H. Kwon, Y. Li, X. Liu, Z. Lu, L. Ou, N. Siddique, P. Sun, P. Vyawahare, O. Winjobi, M. Wu, H. Xu, E. Yoo, G. Zaimes, G. Zang
The GREET® (Greenhouse gases, Regulated Emissions, and Energy use in Technologies) model has been developed by Argonne National Laboratory (Argonne) with the support of the U.S. Department of Energy (DOE). GREET is a life-cycle analysis (LCA) tool, structured to systematically examine the energy and environmental effects of a wide variety of transportation fuels and vehicle technologies in major transportation sectors (i.e., road, air, marine, and rail) and other end-use sectors, and energy systems. Within the transportation sector, GREET covers road, air, water, and rail transportation sub-sectors. Recently, GREET was expanded to cover the building sector. Historically, GREET includes LCA of various materials such as steel, aluminum, cement, and different plastic types. Argonne has expanded and updated the model in various sectors in GREET 2021, and this report provides a summary of the release.
The Carbon Calculator for Land Use and Land Management Change from Biofuels Production (CCLUB) has been developed as an integral part of Argonne National Laboratory's Greenhouse Gases, Regulated Emissions, and Energy use in Technologies (GREET) model to analyze greenhouse gas emissions from land use change and land management change in the context of overall biofuel life-cycle analysis. This document discusses the latest version of CCLUB released October, 2021
Regional Emissions Analysis of Light-Duty Battery Electric Vehicles
A. Burnham, Z. Lu, M. Wang, A. Elgowainy
https://www.mdpi.com/2073-4433/12/11/1482
http://greet.es.anl.gov/publication-regional_ld_bev
Light-duty battery electric vehicles (BEVs) can reduce both greenhouse gas (GHG) and criteria air pollutant (CAPs) emissions, when compared to gasoline vehicles. However, research has found that while today's BEVs typically reduce GHGs, they can increase certain CAPs, though with significant regional variability based on the electric grid mix. In addition, the environmental performance of electric and gasoline vehicles is not static, as key factors driving emissions have undergone significant changes recently and are expected to continue to evolve. In this study, we perform a cradle-to-grave life cycle analysis using state-level generation mix and vehicle operation emission data. We generated state-level emission factors using a projection from 2020 to 2050 for three light-duty vehicle types. We found that BEVs currently provide GHG benefits in nearly every state, with the median state's benefit being between approximately 50% to 60% lower than gasoline counterparts. However, gasoline vehicles currently have lower total NOx, urban NOx, total PM2.5, and urban PM2.5 in 33%; 15%; 70%; and 10% of states, respectively. BEV emissions will decrease in 2050 due to a cleaner grid, but the relative benefits when compared to gasoline vehicles do not change significantly, as gasoline vehicles are also improving over this time.