The Economic and Environmental Case for Cattle Manure and Prairie Grass-Derived Sustainable Aviation Fuel

The aviation sector faces a significant challenge in reducing its greenhouse gas (GHG) emissions to achieve net-zero global CO2 emissions by 2050. Sustainable aviation fuels (SAF) derived from various pathways offer a promising alternative to conventional fossil-based jet fuels. While several SAF pathways are approaching commercialization, cost reduction and long-term sustainability remain critical hurdles. Recent research has highlighted the potential of anaerobic digestion (AD) for SAF production, aligning with a circular economy by repurposing waste materials into valuable energy products. Nonetheless, significant challenges related to scalability, feedstock availability, and refining technologies hinder the widespread adoption of AD-derived SAF. This study addresses these challenges by conducting a techno-economic analysis (TEA) of SAF production using AD, encompassing a multistep process involving feedstock selection, biogas production, biogas refinement, biomethane catalytic conversion into hydrocarbons, and final fuel refinement to meet the stringent specifications required for aviation fuels. The BioSTEAM modeling tool was utilized to establish the minimum fuel selling price (MFSP) of SAF, which is $2.70/L ($10.22/gal). A life cycle assessment (LCA) is also conducted to evaluate the overall environmental impact of the entire process, considering factors such as feedstock sourcing, energy consumption, emissions, and waste management. The global warming potential (GWP) is −260 g of CO2e/MJ. Additionally, sensitivity and uncertainty analyses were applied to evaluate how variations in process adaptations affect both the MFSP and GHG emissions associated with SAF production. This comprehensive assessment highlights the potential of AD-derived SAF in contributing to a sustainable and circular aviation economy, offering valuable insights into its economic and environmental viability for future development and commercialization.