Integration of carbon capture in the production of sustainable aviation fuels (SAF) as a strategy for the decarbonization of the sector

Abstract

The aviation sector contributes to approximately 3% of global CO2 emissions, and this share is expected to rise with the continued growth of air travel. Since electrifying aircraft remains challenging, sustainable aviation fuels (SAF) have emerged as a crucial long-term solution for reducing emissions without requiring changes in aircraft design or global mobility. This thesis aims to assess the feasibility of integrating carbon capture technologies into SAF production, with a specific focus on Power-to-Liquid (PtL) and Biomass-to-Liquid (BtL) pathways. Two main CO2 removal strategies are studied. The first one is Direct Air Capture (DAC), which removes CO2 directly from the atmosphere and will serve as a feedstock for PtL processes, and Biomass Carbon Removal and Storage (BiCRS), which captures CO2 during biomass processing as a feedstock for BtL. Both routes utilize the FischerTropsch synthesis, which is a mature conversion process that enables the production of certified drop-in jet fuel. The findings show that, while PtL offers long-term scalability and deep decarbonization potential, its viability is currently limited by high energy demand and cost but may become attractive in the coming years. BtL appears to be more cost-effective in the short term but comes with significant environmental trade-offs, like land and water use. The Minimum Jet Selling Price (MJSP) results reveal costs of 2–4 €/kg for BtL and 5–7 €/kg for PtL fuels, which is well above fossil jet fuel prices, and the sensitivity analyses highlight the strong influence of electricity, hydrogen, and feedstock prices on overall production cost. From an environmental point of view, PtL pathways powered by renewable energy can reduce life cycle CO2 emissions by up to 88.9% compared to fossil jet fuel, while BtL performance varies significantly based on feedstock sustainability. This thesis demonstrates that integrating carbon capture into SAF production presents a promising pathway for long-term decarbonization of aviation. Although BiCRS may serve as a transitional solution, PtL has the potential to become increasingly viable as renewable energy costs drop and policies such as the ReFuelEU Aviation regulations take effect, mandating minimum e-fuel usage in the coming years.