Evaluation of GHG reduction potentials from municipal solid waste management in Seoul toward carbon neutrality

Seoul, a densely populated megacity, generates a significant amount of municipal solid waste (MSW) and contributes to greenhouse gas (GHG) emissions. Enhancing waste sector strategies has become a critical component of national climate action plans to achieve net-zero carbon emissions by 2050. This study aims to estimate the potential reduction in GHG emissions under current and alternative MSW management systems in Seoul using the Waste Reduction Model (WARM). Scenario-based analysis was employed to compare the business-as-usual (BAU) with three alternative scenarios. Seoul’s MSW generation is expected to keep rising, reaching approximately 4,412 kt/yr by 2040. Scenario analysis showed the GHG reduction in 2040 under BAU scenario is estimated at -3,554 kt CO2 eq/yr. However, Scenario 3 (S3), which reflects ambitious efforts on MSW management, could achieve GHG reduction up to 76% higher than BAU. This study highlights that source reductions and recycling are the most effective methods for reducing GHG emissions, particularly from high-impact materials such as mixed paper and food waste. The results of this study provide a data-driven foundation for designing future solid waste policies and setting targets to support Seoul’s carbon neutrality goals.