Greenhouse Gas Emission Factors for Municipal Waste Combustion and Other Practices

Waste management practices can impact greenhouse gas (GHG) emissions by affecting energy consumption, methane generation, carbon sequestration, and non-energy-related manufacturing emissions. This paper examines GHG emissions and sinks, from a life-cycle perspective, for selected paper, glass, metal, and plastic materials comprising about one-third of municipal solid waste (MSW) generated in the US; it also provides information on mixed MSW. Some key methodologic considerations for estimating GHG emissions associated with combustion are briefly described. Manufacturers, solid waste decision-makers, and others interested in the GHG implications of MSW management may use this information for voluntary reporting of GHG emission reductions associated with waste management practices and to develop strategies to reduce GHG emissions. Each of the waste management options provides opportunities for GHG reductions for one or more materials. The relative advantages of combustion versus landfilling depend on several factors, chiefly the extent to which landfill methane releases are controlled, the extent of long-term carbon storage in landfills, and the magnitude of utility fossil fuels displaced by electricity generation at the combustion facility.