Tracking the life-cycle greenhouse gas emissions of municipal solid waste incineration power plant: A case study in Shanghai

Municipal solid waste incineration (MSWI) has become the predominant waste-to-energy technology in China. The present work addresses an onsite greenhouse gas (GHG) emissions accounting approach for MSWI plants. A comprehensive life-cycle GHG emissions assessment model was developed and applied to a case study in Shanghai. Different methods (Method 1: CO₂ concentration measurement-based method; Method 2: O₂ concentration measurement-based method; and Method 3: Intergovernmental Panel on Climate Change (IPCC) 2006 guidelines-based method) were compared for calculating the fossil CO₂ emissions (FCO₂E) originating from waste incineration. The results indicate that the deviations of FCO₂E among different methods could be effectively reduced by modifying the dry matter (DM) content since the waste in China is commonly featured by high moisture content. Moreover, the life-cycle GHG emissions of MSWI in each month ranged from 11.2 to 622.4 kg CO₂-eq/t MSW, in which FCO₂E yielded the most significant impact. The seasonal characteristics of GHG emissions were directly related to variations in the waste components. In particular, a high plastics fraction in the waste streams after source separation contributed to high levels of GHG emissions originating from Chinese MSWI plants. It was demonstrated that GHG emissions increased by approximately 12.1 kg CO₂-eq/t MSW with a 1% increase in the plastics fraction. Therefore, properly increasing the recycling rate of plastics and improving the power generation efficiency could effectively reduce the GHG emissions associated with MSWI.