The full report is available at Appendices - Individual Studies LBL Study Summary of Exploration of Resource and Transmission Expansion Decisions in the Western Renewable Energy Zone (WREZ) Initiative Lawrence Berkeley National Laboratory February 2010 Overview This LBL study uses an Excel-based model, developed as part of the WREZ initiative, to evaluate the relative economic attractiveness of renewable resources to the major load zones of the WECC. The primary metric is delivered cost” (ADC) and the model uses a least-cost algorithm to identify which resources and “adjusted transmission are needed to meet varying levels of RPS requirements while respecting the limited quantities of high quality resources that are attractive to multiple load centers. The comparison of relative economic attractiveness between various load centers can uncover potential for collaboration (on common transmission needs, for example) or competition to secure attractive resources. It is important to note that this is a high-level screening model driven by very broad (but reasonable) simplifying assumptions. The study points out rational patterns of renewable resource and transmission development and the importance of various changes in assumptions and policies. However, it is of limited value in looking at the issues of renewable integration, operational feasibility or reliability. For example, the design is to meet annual, RPS energy requirements up to 33% RPS levels. While the ADC method incorporates factors to reflect “value to the electricity system”, the annual energy approach precludes consideration of seasonal or diurnal variations, operational feasibility, reliability or such issues as local market disruptions at high penetration levels of a single renewable technology. Assumptions and Design The following are some of the key assumptions and methods of the study: Test year of 2029 RPS requirements are WECC-wide and are tested at 12%, 25% and 33% Resources are WREZ-identified resource hubs only. Hubs are discrete geographic concentrations of environmentally preferred renewable resources that might justify a new 1,500 MW transmission line. Adjusted Delivered Cost is defined as: Bus-Bar Cost PLUS Transmission costs (including losses) PLUS Integration cost LESS Capacity LESS Time of day energy Solar assumed financed with 25-year debt, all others 15-year New transmission assumed to be required between resource and load, costs assigned on a pro-rata share (lumpiness ignored)
The full report is available at Appendices - Individual Studies LBL Study Summary of Exploration of Resource and Transmission Expansion Decisions in the Western Renewable Energy Zone (WREZ) Initiative Lawrence Berkeley National Laboratory February 2010 Overview This LBL study uses an Excel-based model, developed as part of the WREZ initiative, to evaluate the relative economic attractiveness of renewable resources to the major load zones of the WECC. The primary metric is “adjusted delivered cost” (ADC) and the model uses a least-cost algorithm to identify which resources and transmission are needed to meet varying levels of RPS requirements while respecting the limited quantities of high quality resources that are attractive to multiple load centers. The comparison of relative economic attractiveness between various load centers can uncover potential for collaboration (on common transmission needs, for example) or competition to secure attractive resources. It is important to note that this is a high-level screening model driven by very broad (but reasonable) simplifying assumptions. The study points out rational patterns of renewable resource and transmission development and the importance of various changes in assumptions and policies. However, it is of limited value in looking at the issues of renewable integration, operational feasibility or reliability. For example, the design is to meet annual, RPS energy requirements up to 33% RPS levels. While the ADC method incorporates factors to reflect “value to the electricity system”, the annual energy approach precludes consideration of seasonal or diurnal variations, operational feasibility, reliability or such issues as local market disruptions at high penetration levels of a single renewable technology. Assumptions and Design The following are some of the key assumptions and methods of the study: Test year of 2029 RPS requirements are WECC-wide and are tested at 12%, 25% and 33% Resources are WREZ-identified resource hubs only. Hubs are discrete geographic concentrations of environmentally preferred renewable resources that might justify a new 1,500 MW transmission line. Adjusted Delivered Cost is defined as: Bus-Bar Cost PLUS Transmission costs (including losses) PLUS Integration cost LESS Capacity LESS Time of day energy Solar assumed financed with 25-year debt, all others 15-year New transmission assumed to be required between resource and load, costs assigned on a pro-rata share (lumpiness ignored)
PEFA_WIST_WISTReportFinalJanuary2011-1-.docx