Sustainable aviation fuels (SAF) are low carbon fuels derived from a variety of biogenic and non-biogenic sources. Each version of SAF must meet international standards regulated by the American Society of Testing and Materials (ASTM) and for use in commercial flights, must be certified under a sustainability certification scheme.
SAF, once blended with conventional aviation fuel in accordance with relevant specifications, is a drop-in replacement fuel, requiring no changes to aircraft, airport infrastructure or jet fuel supply chains. As a result, SAF offers the single largest opportunity to reduce emissions for airlines in the medium term while ensuring long-term fuel security for the sector.
SAF contributes lower levels of carbon emissions compared to traditional fossil jet fuel on a lifecycle basis and can be derived from sustainable sources. When fully replacing conventional jet fuel, SAF derived from sustainable feedstocks can achieve lifecyle emissions savings of over 70 per cent. SAF has undergone rigorous safety certification testing and is now used at major foreign international airports. Over 450,000 commercial flights have used SAF, and this number is growing.
Australia is an existing and significant SAF feedstock producer, but SAF is not yet in commercial production here. The current cost of SAF is much higher than conventional jet fuel and for SAF to scale, prices need to be reduced. The main cost drivers are feedstock costs, yields, and plant capital recovery.
SAF can be produced from biomass from plants, trees, algae, waste and other organic matter but can also be produced synthetically via a process that captures carbon from the air. To date, SAF produced from oils and fats through a process that uses hydrogen (HEFA) has produced 95 per cent of the world’s SAF. Synthetic SAF, although holding great promise of providing the most emissions saving potential, needs much more investment in technologies and production pathways.