The base case environmental results indicate that the activities associated with collection, transport and disposal of domestic have a global warming potential (GWP) of 38,993t CO2,eq, out of a system total of 41,790t CO2,eq. As a consequence of the high organic content of the municipal waste, and a predominantly landfill-based system, this is expected as it leads to a significant potential for methane production potential. Table 2 below shows a full breakdown of GWP by activity. The overall system as illustrated in Figure 3 earlier shows that the biggest contributors to global warming are (i) domestic waste collection and disposal and (ii) the composting (Stellenbosch University). Composting organic waste naturally results in the formation of CO2, with a global warming potential (GWP) approximately 21 times less than the methane (CH4) that would have been generated from landfill anaerobic processes. However the large GWP for waste collection and disposal is also associated with the relative volume of waste going to landfill 47% of domestic waste is organic – waste on average, and domestic waste is roughly 15 times the amount of recycled waste in Stellenbosch (Appendix 5). The negative numbers for recycling (both municipal and private) indicate that there is a net reduction in CO2 in the aggregated recycling value chains, despite some of the large distances travelled. Although the processes for conversion of e.g. paper to cardboard still result in an increase CO2 emissions, the results below show that the net savings associated with avoiding the production of the substituted product is much bigger than the CO2 emissions from recycling. : Global warming potential of the different activities Activity GWP - tonnes CO2,eq Domestic waste collection and disposal 38,993 Stellenbosch University organic composting 3,112 Municipal recycling -157 Private recycling -158
The base case environmental results indicate that the activities associated with collection, transport and disposal of domestic have a global warming potential (GWP) of 38,993t CO2,eq, out of a system total of 41,790t CO2,eq. As a consequence of the high organic content of the municipal waste, and a predominantly landfill-based system, this is expected as it leads to a significant potential for methane production potential. Table 2 below shows a full breakdown of GWP by activity. The overall system as illustrated in Figure 3 earlier shows that the biggest contributors to global warming are (i) domestic waste collection and disposal and (ii) the composting (Stellenbosch University). Composting organic waste naturally results in the formation of CO2, with a global warming potential (GWP) approximately 21 times less than the methane (CH4) that would have been generated from landfill anaerobic processes. However the large GWP for waste collection and disposal is also associated with the relative volume of waste going to landfill – 47% of domestic waste is organic waste on average, and domestic waste is roughly 15 times the amount of recycled waste in Stellenbosch (Appendix 5). The negative numbers for recycling (both municipal and private) indicate that there is a net reduction in CO2 in the aggregated recycling value chains, despite some of the large distances travelled. Although the processes for conversion of e.g. paper to cardboard still result in an increase CO2 emissions, the results below show that the net savings associated with avoiding the production of the substituted product is much bigger than the CO2 emissions from recycling. : Global warming potential of the different activities Activity GWP - tonnes CO2,eq Domestic waste collection and disposal 38,993 Stellenbosch University organic composting 3,112 Municipal recycling -157 Private recycling -158
Case-Study-report-Stellenbosch-Final.docx