Holistic Methodology to Guide the Evolution of Sustainable Aviation Fuel Production Technologies

Sustainable aviation fuel (SAF) production is an area of intense research, with many production pathways competing for commercialization in a rapidly changing policy environment. Current techno-economic methods to discern minimum selling price (MSP) can require extensive research and be difficult to generalize to the guidance of emerging technologies. There is a need for more flexible methods to guide the evolution of SAF production toward economically and environmentally viable pathways. We present the following technology-neutral heuristic to approximate MSP, then demonstrate its use to evaluate strategies to minimize the cost of CO2 abatement for a given SAF process. We first apply it to stoichiometric cases based on the method of oxygen removal (in the form of H2O, CO2, or O2), which serves as paradigm targets for technological evolution. Our analysis indicates that in a favorable green hydrogen market (prices below 2.50 $/kg), oxygen removal as H2O is preferable, while removal as CO2 is preferable at current hydrogen prices. Carbon supplements from lower-oxygen-content sources (such as plastic) and sequestration (such as char) were also shown to potentially reduce production and abatement costs for stoichiometric models. These findings held true when applying this heuristic to model a fast pyrolysis process with waste plastic supplements reducing abatement costs while still meeting CI reduction criteria. The heuristic was also used to evaluate potential evolution paths for gasification/Fischer–Tropsch technologies. A similar trend to the stoichiometric models emerged, with a significant reduction in hydrogen cost and CI required to justify supplementing the process. In this way, we demonstrate a novel approach to the screening and evolution of SAF processes toward viability and efficiency.