Sustainable Aviation Fuel 2.0: Carbon- and Contrail-Intensity Managed Refineries for Climate-Smart Aviation

Abstract

Sustainable aviation fuel (SAF) is entering the mandate era while still representing a sub-percent share of global aviation fuel. This Perspective argues that the next bottleneck is not only production capacity, but climate allocation: which carbon sources, hydrogen, renewable electrons and molecular structures should become jet fuel, and where that fuel should be deployed to deliver the greatest avoided climate impact. SAF 2.0 is proposed as a carbon- and contrail-intensity managed refinery–airport architecture that links certified HEFA, Fischer–Tropsch, alcohol-to-jet, power-to-liquid/e-SAF and co-processing modules with molecular finishing, digital monitoring, reporting and verification, and targeted fuel dispatch. In this framework, hydrogen content, sulfur, naphthalene, aromatics and cycloparaffins are treated as design variables affecting soot, non-volatile particulate emissions and contrail-forming potential, rather than as secondary specification details. A Climate Yield Factor is introduced as a screening metric to compare pathways and deployment options by avoided climate impact per unit of scarce carbon, hydrogen, electricity, feedstock and cost. The Perspective closes with an R&D agenda for refinery–airport demonstration hubs able to accelerate SAF scale-up while avoiding first-generation feedstock bottlenecks and volume-only compliance logic.