2026-05-14 チャルマース工科大学
＜関連情報＞
- https://news.cision.com/chalmers/r/eu-rules-could-make-fossil-free-aviation-fuels-unnecessarily-expensive-and-energy-intensive,c4348579
- https://www.sciencedirect.com/science/article/pii/S0016236125029060
RFNBOに固執する――EUが義務付けるドロップイン型合成航空燃料は、エネルギー効率とコスト効率の低下につながるのか？ Locked in on RFNBOs – Will EU mandates for drop-in synthetic aviation fuels lead to decreased energy- and cost-efficiency?
Johanna Beiron, Simon Harvey, Henrik Thunman
Fuel Available online: 21 October 2025
DOI:https://doi.org/10.1016/j.fuel.2025.137181
Highlights
- Comparison of methanol synthesis based on combustion or gasification of biomass.
- Gasification outperforms combustion options in terms of cost and energy efficiency.
- Policies requiring CO2-based fuel synthesis create lock-in in sub-optimal system.
- RFNBO rules are in conflict with energy efficiency directive and waste hierarchy.
- Regulatory inconsistency increases investment risk that could slow down deployment.
Abstract
Decarbonization of the transportation sector implies that fossil fuels must be substituted with sustainable alternatives. Current EU policies incentivize large-scale deployment of synthetic aviation fuel production that can be classified as Renewable Fuel of Non-Biological Origin (RFNBO). Synthetic aviation fuel can be produced from methanol and this work presents a techno-economic assessment of three pathways (two combustion-based and one gasification-based) to produce synthetic methanol from biomass residues and renewable hydrogen. The results show that the gasification-based pathway can produce methanol at a lower cost (820 €/t methanol) and higher energy efficiency (46 %, for conversion of biomass, electricity and heat inputs to methanol) compared to combustion-based options (1,050–1,500 €/t methanol and ∼37 % efficiency). The gasifier route requires less renewable hydrogen, resulting in a 30 % lower electricity demand. However, only 55 % of the gasification-based methanol is compliant with the RFNBO definition, since the regulation stipulates that biofuel cannot be counted towards the drop-in quotas. Furthermore, the findings indicate that RFNBO policies that favor production using CO2 from combustion processes that supply energy to utility systems (e.g., district heating) risk leading to lock-in in inefficient systems, as electrification of heat supply could be a more efficient option. This work identifies such regulatory inconsistencies that increase risk related to investment decisions.
