Biogas utilisation – Life cycle assessment of enabling technology for transport biomethane - UK case study, Bore Hill farm Biodigester

Policies, implemented and being considered in the UK, promote the use of biogas from anaerobic digestion (AD); however, small-medium scale AD plants, the majority of the UK's AD plants, have little access to energy distribution networks. The opportunity for using biomethane (upgraded biogas) for transportation, is rewarded in the Renewable Transport Fuels Obligation (RTFO), offering the AD plants the lowest cost route to achieving the targets set out in the Biomass Strategy for biomethane. In this study, Life Cycle Assessment is used to demonstrate the environmental benefits of using biomethane for transportation (considering global warming potential and fossil fuel scarcity impacts), compared to a biogas-to-electricity scenario, where the gas grid is not accessible. The results show that biomethane scenarios have significant environmental advantages in selected impact categories, evidencing that biomethane for transportation can decarbonise AD industries and contribute to the Net Zero target in the UK. Biomethane scenarios show greater potential for capturing biogenic CO 2 . However, biogas upgrading technologies, evolving technically and economically, should be studied further through techno-economic assessments for the appropriate scale and application in AD operations. This study contributes to the UK AD industry and policy makers concerned with the decarbonisation of biogas-to-biomethane routes for the future. • Key Highlights. • Biomethane used for transportation in the UK was assessed with LCA. • Environmental benefits by biomethane are identified. • Biogas composition and types of upgrading technology are sensitive to the impacts. • Potentials for CO 2 captured from biomethane uses are recognised.