Strategic assessment of sustainable aviation fuel production technologies: Yield improvement and cost reduction opportunities

Abstract

The aviation industry has been studying strategies to produce sustainable aviation fuels (SAF) for over ten years. Our objective is to conduct detailed techno-economic analyses (TEA) of six SAF production technologies and to develop a simplified cost estimation method. Triglyceride based Hydroprocessed esters and fatty acids (HEFA) was compared against five lignocellulose-based technologies using standardized criteria. TEA was conducted to determine minimum fuel selling price (MFSP). The base case annual product capacity was fixed at 60 million liters of total fuel, for which SAF MFSPs ranged from 0.88 to 3.86 $ L−1 of fuel. Triglyceride-based HEFA had the best economic performance. Although triglycerides are more expensive than lignocellulose, HEFA is still a very competitive technology due to its high fuel yield (86–91% of feedstock) and low MFSP. Lignocellulosic-based technologies have lower fuel yields (9–23% of feedstock) due to high oxygen content of initial feedstock, resulting in higher fuel cost per unit of fuel. In order to reach a market fuel price, SAF yields from lignocellulosic materials needs to achieve an estimated value of 60%. Such yields are only possible if carbon efficiencies are close to 100%. Therefore, efforts are needed to avoid the removal of oxygen as CO2. Based on these considerations, a new scheme is proposed for SAF production that could result in yields near those needed to achieve cost targets. This proposed integrated biomass/natural gas hybridized concepts to produce inexpensive SAFs should be thoroughly investigated in future work.