A stakeholders' participatory approach to multi-criteria assessment of sustainable aviation fuels production pathways

Sustainable aviation fuels (SAF) provide a viable option to decarbonise global aviation. Unlike conventional jetfuel, SAFs can be produced in several production pathways making their selection a complex multi-criteria decision making (MCDM) problem with conflicting objectives. In this paper, we propose a multicriteria based framework for evaluating SAF production pathways, which is a sequential decision-making process with feedback adjustment mechanisms. Given the early stage of SAF technologies' development and the scarcity of data on such technologies, in this research, we involved a variety of aviation industry stakeholders to assist with data and preference gathering. Our MCDM framework is designed to be generic to provide flexibilities to potential users in choosing the appropriate implementation decisions for the relevant stakeholders. The strength of the proposed framework lays in its flexibility to accommodate various stakeholders' subjective judgements, choice of ranking method, and robustness of results. We used our MCDM framework within a stakeholders' participatory approach to rank order 11 SAF production pathways against 24 criteria grouped under social, environmental, economic, and technical impact categories. Our analysis revealed that the environmental and the economic impact categories are the most important ones followed by the technical and the social criteria; the gasification/FischerTropsch (F-T) based production processes are preferred over fermentation and oil-based ones; and waste gases are the preferred feedstock along with wood-residue. These findings provide decision-makers with guidelines on the selection of SAF production pathways.