Comparative life cycle assessment of landfill gas utilization in South Korea with parametric uncertainties

Landfill gas, a major contributor to global CH4 emissions, which have a much greater impact on global warming than CO2 does, is inevitable as a waste derivative. Upcycling landfill gas into value-added products is a powerful strategy to reduce greenhouse gas emissions and to use materials in a circular system. This study presents a full life cycle assessment of electricity produced using landfill gas at the Sudokwon landfill site, the largest case of landfill gas upcycling in South Korea. To ensure the representativeness of the results, we used statistical data to capture the technical and regional characteristics of the national market share as primary data. In addition, a parametric uncertainty analysis integrated with data quality assessment was conducted to reflect the temporal dynamics of landfills and enhance the reliability of this study. Our findings demonstrate that upcycling landfill gas into electricity is environmentally beneficial across sixteen impact categories compared with two baseline scenarios that do not involve landfill gas upcycling. The methodological approaches presented herein can address multifunctional challenges in waste treatment systems and improve the reliability of life cycle inventories.