Assessing biogas valorization from municipal organic waste in India: Integrated environmental-economic analysis

Addressing a major literature gap, this study provides the first integrated environmental-economic evaluation of five biogas utilization pathways from organic fraction of municipal solid waste (OFMSW) in India: flaring, electricity generation, direct cooking use, upgraded biomethane for cooking, and vehicle fuel. The life cycle assessment (ReCiPe 2016) and techno-economic analysis of 25-500 tonnes per day (TPD) bio-CNG plants reveal that energy recovery options offer major environmental benefits, with electricity generation achieving the highest global warming reduction (-123 kg CO₂-eq/ton), followed by direct biogas use for cooking (-108 kg CO₂-eq/ton). Upgradation-intensive routes showed lower benefits due to methane losses (-12 to -11 kg CO₂-eq/ton). Economically, plants below 120 TPD were unviable (for 25 TPD payback is >20 years), while larger units (with and without subsidy), especially 500 TPD plants, achieved payback <5 years with digestate valorization. The findings provide actionable guidance for India's waste-to-energy and bio-CNG policies by demonstrating how optimal plant scale, process efficiency, and byproduct utilization can accelerate national circular-economy and low-carbon goals.