What is SAF (Sustainable Aviation Fuels) ?
SAFs are a collection of fuels with two common denominators: they are drop-in fuels by design and are made from renewable feedstock. SAF is chemically equivalent to conventional jet fuel and can be blended with, or “dropped in” to, conventional fuel.
For these reasons, SAFs require no manipulation of plane engines, can be distributed and stored in existing infrastructure, and can be handled by airports with no additional complexity. These properties give SAF tremendous appeal for airlines and other aviation stakeholders. According to IATA, SAF has the potential to replace 65% of conventional jet fuel by 2050, but with this 30-year perspective, really the sky is the limit.
SAFs can be divided in two groups based on feedstock, and these are bio- and synthetic fuels. Bio-derived fuels use organic matter, for example used cooking oil, animal fats, household waste, and energy crops, as feedstock, while synthetic alternatives are created from CO2 captured from the air or from industry emissions. The latter fuels are currently in experimental development while the HEFA-production process of using biomass such as cooking oil is a mature technology and can be industrialized. However, other organically based approaches are still technologically immature, and processes such as gasification, turning household waste into fuel, alcohol-to-jet production, and converting wood-based waste, such as used pallets and forestry residue, into SAF will be established over the coming decade.