EU rules designed to scale up renewable jet fuel risk locking the forestry sector into production routes 46 per cent more expensive than the cheapest available pathway, new peer-reviewed Swedish research has found. That is according to a new analysis by Johanna Beiron, Simon Harvey and Henrik Thunman at Chalmers University of Technology, published in the Fuel journal, which compares three production routes for making synthetic aviation fuel from forest industry residues and renewable hydrogen.
The Chalmers team modelled three routes for producing synthetic methanol — the chemical building block converted into sustainable aviation fuel — using carbon from forest residues and renewable hydrogen. Two of the routes burn the wood biomass first to capture its carbon dioxide for use in fuel synthesis, while the third heats the biomass into a carbon-monoxide-and-hydrogen synthesis gas that feeds directly into methanol production.
At 820 euros per tonne, the gasification pathway produces synthetic methanol at the lowest cost of the three routes, with the analysis listing electricity consumption of 1.2 megawatts per megawatt of methanol and energy efficiency of approximately 46 per cent. The same modelling lists 1,055 euros per tonne for combustion with carbon capture and 1,495 euros per tonne for combustion with capture and simultaneous energy production, both running at roughly 37 per cent efficiency.
Across both combustion alternatives, the gasification pathway records up to 46 per cent lower production cost and 30 per cent lower electricity demand, the analysis states. Yet only 55 per cent of gasification output qualifies under the EU’s Renewable Fuel of Non-Biological Origin (RFNBO) framework, with the authors writing in Fuel that “the regulation stipulates that biofuel cannot be counted towards the drop-in quotas.”
Under the ReFuelEU Aviation regulation in force since 2025, EU airports must offer a rising minimum share of sustainable aviation fuel — from 2 per cent now to at least 70 per cent by 2050 — with half of the 2050 volume required to come from RFNBO electrofuels produced from renewable hydrogen and captured carbon dioxide. The framework counts combustion-based routes in full but excludes the biomass-derived share of gasification output, because RFNBO fuels may not be produced using energy and carbon atoms directly derived from biomass.
With RFNBOs projected to expand from close to zero today to 35 per cent of all EU aviation fuel by 2050, the Chalmers paper finds that the eligibility definitions favour combustion-and-capture routes that source biogenic carbon dioxide from wood-biomass flue gases over the direct gasification of the same feedstock. The paper points to “regulatory inconsistencies that increase risk related to investment decisions” across the long-lived synthetic aviation fuel capacity Europe will commit to through the next two decades.
The modelling comes as European oil-market attention returns to energy security following the Iran war, with the Chalmers team warning that capturing carbon dioxide from combustion plants tied to district heating networks could entrench less efficient utility systems precisely when direct electrification of those networks would deliver better energy returns.
For more information: Johanna Beiron, Simon Harvey, Henrik Thunman,
Locked in on RFNBOs – Will EU mandates for drop-in synthetic aviation fuels lead to decreased energy- and cost-efficiency?, Fuel, Volume 406, Part D, 2026, 137181, ISSN 0016-2361, https://doi.org/10.1016/j.fuel.2025.137181.
