What is sustainable aviation fuel?

ASTM International, a global standards and testing body, has approved eight technical pathways for the production of SAF. Three of the most common methods of SAF production are:

• HEFA (Hydrotreated Esters and Fatty Acids): The HEFA process refines vegetable oils, waste oils, or fats into SAF through hydrotreating and hydroprocessing. 
• Alcohol-to-Jet: Alcohol-to-Jet (AtJ) converts alcohols such as ethanol and iso-butanol into SAF by removing the oxygen and linking the molecules together. 
• eFuels: SAF can be produced using hydrogen, capturing carbon dioxide, and using renewable electricity to create synthetic fuels. This type of SAF is sometimes referred to as eFuel or Power-to-Liquid (PtL).

Not all production methods and feedstocks are created equal and some SAF feedstocks unlock greater emissions savings across the lifecycle than others. Nonetheless, exploring different methods will help the SAF industry to scale, improving SAF availability and supply.
 

The main challenge remains the emergence of a market to generalise the use of SAF. There is both a demand and supply challenge.

• Cost of SAF: Even though the quantity of SAF available has increased in recent years, demand remains suppressed due to the higher cost of SAF compared to kerosene. The industry has to address this disparity and reduce the price gap with traditional fuel. 
• Policies and regulatory frameworks needed: SAF development and adoption is hindered by a lack of consistent and supportive policies, as well as clear and stable.
• Availability of SAF: SAF production has dramatically increased in recent years but SAF still accounts for a very small portion of globally consumed jet fuel. In the long term, significant investments in new facilities are needed to scale up production. 
• Availability of SAF feedstocks: Securing sustainable and scalable feedstocks from which to produce SAF is a major challenge. Ensuring that these feedstocks do not compete with food production or negatively impact ecosystems is a key consideration which further limits availability of viable feedstocks. 
• Technological maturity: While several SAF production pathways exist, some are more nascent than others. Continuous innovation is needed to improve production efficiency and reduce costs. The certification process can also take time. 

SAF is considered by the leading aviation authorities and regulatory bodies as a key contributor to reach the industry’s target of net-zero carbon emissions by 2050, as set by ICAO, ATAG and IATA. Airbus agrees that SAF represents a crucial pathway to reducing the aviation sector’s greenhouse gas emissions and is committed to advancing SAF use across the industry.

Airbus is acting as a catalyst to encourage the uptake of SAF and to promote increased use of SAF. From deploying SAF in its own operations to making strategic partnerships and investments, Airbus is acting in a number of ways to foster the growth of the SAF ecosystem.