Fueling a green future: unlocking the environmental potential of CO2-derived power-to-X liquid fuels via life cycle assessment

Abstract

Decarbonizing the transport sector requires integrating renewable energy with carbon capture technologies to produce sustainable fuels. This study evaluates four wind-powered Power-to-X (P2X) fuel systems, each using a different CO₂ source: biogas, cement production, direct air capture (DAC), and steel manufacturing. Life cycle assessment (LCA) across seven environmental impact categories shows that all P2X pathways result in substantially lower environmental impacts compared to conventional fossil- and biomass-based fuels, with global warming potentials of 2480 and 1710 kg CO₂ eq. per t_fuel, respectively. The P2X systems achieved a global warming potential (GWP) of 81.3–97.9 kg CO₂ eq. per t_fuel, corresponding to 98% greenhouse gas savings relative to the RED III fossil fuel benchmark. The cement-derived CO₂ scenario offers the lowest impacts due to reduced energy and material demands in CO₂ capture, while DAC incurred the highest burdens due to elevated energy and material requirements. Under Finnish conditions, utilization of excess heat from the P2X processes could supply 555–595 households, displacing 1191.6–2456.4 t CO₂ per year from light fuel oil and 1709.9–1832.8 t CO₂ per year from natural gas, while generating €827k–886k in annual revenue. These findings highlight the potential of strategically sourced CO₂ and renewable energy integration to deliver low-carbon fuels with significant environmental and socio-economic co-benefits in regions with comparable renewable and district heating infrastructures.