Biomass as a transportable biogenic carbon carrier for e-methanol production: Techno-economic comparison with CO2 transport and direct air capture

The increasing role of e-fuels in defossilising hard-to-electrify sectors and the growing importance of carbon capture and utilisation require a reliable carbon supply. This study presents a comparative techno-economic assessment of four carbon supply pathways for e-methanol production in Finland, Germany, and Spain for 2030-2050: transport of captured biogenic CO 2 , transport of biomass as a carbon carrier, local biomass utilisation with carbon capture, and direct air capture. Aspen HYSYS and Aspen Process Economic Analyzer were used for CO 2 conditioning and transport, combined with literature-based cost modelling for CO 2 and biomass logistics, biomass power (PP) and combined heat and power (CHP) plants, cement sector biomass use, direct air capture, and e-methanol synthesis. In cement cases, only biogenic CO 2 is allocated to methanol. Results indicate that the cement scenarios with imported biomass have the lowest e-methanol production costs under the stated cost allocation, at 54.6-75.4 €/MWh MeOH,LHV in 2050 in Germany and Spain. The local biomass PP and CHP scenarios cost 73.8-96.0 €/MWh MeOH,LHV . The imported biomass PP can be the least attractive options, costing 92.5-110.8 €/MWh MeOH,LHV . e-Methanol production with DAC remains expensive in 2030 but becomes competitive by 2050 due to technology improvement. Although transporting biomass is considerably cheaper than CO 2 , the latter results in lower total e-methanol costs due to the absence of downstream biomass conversion. Results demonstrate that carbon supply should be treated as a system-level question rather than only a transport problem. Furthermore, beyond acting as a renewable fuel, biomass can serve as a strategic carbon carrier for e-fuel systems.