From landfilling to waste incineration: Implications on GHG emissions of different actors

Abstract Concern over climate change has increased the efforts for climate change mitigation in cities and companies. At the same time, the EU policies promote material and energy recovery from waste, and the production of energy from renewable sources. In the energy system, the replacement of another energy production plant with a waste to energy plant (WTE) may either increase or decrease the total emissions. Cities and companies calculate their greenhouse gas emissions or carbon footprints using various calculation protocols, and a change from landfilling to waste incineration affects the emissions of these actors in various ways depending on the system boundaries. In this contribution, impact of a change from landfilling to WTE on the emissions of different actors is calculated for the case in which WTE replaces separate production of district heat (DH) by natural gas and electricity by coal. In the case of a waste management company, emissions decreased from about 51 kt CO2-eq in 2009 (before introduction of the WTE) to −33 kt CO2-eq in 2030. Emissions of DH company decreased by 40%, whereas at the city-level the combined emissions of waste management and district heat consumption decreased 60% between 2009 and 2030. The significance of the energy source to be replaced by energy from WTE on the potential GHG emission reductions was also calculated for different options. The emissions of electricity and district heat produced by WTE were 35–60% smaller than emissions from separate production of district heat by oil or natural gas and production of electricity by natural gas or coal. When electricity and DH produced by the WTE replaced those produced by alternative CHP plants, the impact varied from increase of emissions by 50% to decrease of emissions by 40% depending on the fuel of the CHP plant and electricity source used to cover the smaller electricity generation by the WTE. However, in all the cases, when the avoided emissions from landfilling were taken into account, the emissions of WTE were smaller than those of alternative waste management and energy generation options over time.