Production of fuels and fuel additives from biogas: Technical and environmental assessment

The decarbonisation of the transport sector requires integrated assessments of renewable fuel production pathways that simultaneously address process performance and environmental impacts. The current study develops and compares five integrated biogas valorisation routes for the production of Methanol (MeOH), Dimethyl Ether (DME), Methyl Tert-Butyl Ether (MTBE), Dimethyl Carbonate (DMC), and 2-Methoxy-2-Methyl-Heptane (MMH). Process simulations were performed in CHEMCAD, v7.1.2, incorporating heat integration and on-site power generation. The systems were scaled for a production of 100 kmol/h, for each distinctive desired product, and evaluated using key technical performance indicators. A cradle-to-gate Life Cycle Assessment (LCA) was conducted using Sphera®’s LCA for Experts, version 10.8, and the ReCiPe 2016 method to quantify impacts across ten midpoint categories. All pathways were assessed under harmonised system boundaries and compared with conventional natural gas-based production routes. The results indicate that biogas-based production reduces global warming potential (GWP) by 73 – 78% relative to fossil-based references for MeOH and DME, with greenhouse gas emissions ranging from 0.25 to 0.29 kg CO2 eq./kg (product). Among the evaluated pathways, DME and MeOH exhibit the most favourable combined performance, achieving cumulative energy efficiencies of up to 60.33% and the lowest fossil depletion impacts. In contrast, MTBE, DMC, and MMH display higher environmental burdens due to the requirement for petrochemical intermediates, highlighting the critical role of upstream feedstock selection. Overall, this study provides a systematic and harmonised techno-environmental comparison of biogas-derived fuels and fuel additives, offering quantitative decision-support insights for prioritising renewable fuel integration in the transport sector.