Nigeria's Sustainable Aviation Fuel

Using non-petroleum feedstocks as the basis for sustainable aviation fuel (SAF), air transportation emissions are reduced. Based on the feedstock used and the way the fuel is produced, SAF can be blended at different levels with limits ranging from 10% to 50%. Over 360,000 commercial flights have been operated with SAF at 46 airports in 46 countries, mostly in the United States and Europe, according to the International Civil Aviation Organization (ICAO).

Globally, aviation contributes 2% of total carbon dioxide (CO2) emissions and 12% of those from transportation. To limit the net CO2 emissions from aviation to 2020 levels until 2035, ICAO has implemented the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA). In an effort to achieve carbon neutrality by 2050, the international aviation sector has set a target to reach net zero carbon. Sustainable Aviation Fuel (SAF) is currently the most viable option for meeting these objectives in the near future. In line with this, a Sustainable Aviation Fuel Grand Challenge was launched in 2021, bringing together various federal agencies with the aim of increasing domestic consumption to 3 billion gallons by 2030 and 35 billion gallons by 2050, while also reducing lifecycle greenhouse gas emissions by at least 50%.

The benefits

The benefits of renewable hydrocarbon biofuels include:

Using SAF blended with conventional Jet A in existing aircraft and infrastructure is possible.

With 100% SAF, greenhouse gas emissions can be reduced by up to 94% compared to conventional jet fuel.

SAF allows for the production of multiple products using a variety of feedstocks and production technologies as an alternative to conventional jet fuel.

The production process

Non-petroleum-based renewable feedstocks that can be used to produce SAF include, but are not limited to, food and yard waste from municipal solid waste, woody biomass, fats/greases/oils, and others. The production of SAF is in its infancy, with three commercial producers currently known:

In 2016, World Energy began producing SAF at its Paramount, California, facility and initially supplied fuel to Los Angeles International Airport.

Neste began supplying SAF to the San Francisco International Airport in 2020, before expanding to other California airports in 2021 and 2022, and to Aspen/Pitkin County Airport and Telluride Regional Airport in Colorado.

In 2023, Montana Renewables LLC began providing fuel to several airline partners in partnership with Shell.

New domestic plants are expected to be constructed. Many airlines have signed contracts with existing and future SAF producers to utilize the entire output. As part of the Renewable Fuel Standard, the U.S. Environmental Protection Agency (EPA) collects information about renewable fuel consumption, including SAF. According to the EPA, approximately 5 million gallons of SAF were consumed in 2021, 15.84 million gallons in 2022, and 24.5 million gallons in 2023.

There are various technology options for producing fuels that adhere to ASTM standards and blending limitations. The ASTM D7566 Standard Specification regulates the quality of non-petroleum jet fuel and specifies permissible levels of SAF-based blends with Jet A. The established plants currently utilize the hydroprocessed esters and fatty acids method, as indicated in the table below. However, upcoming domestic facilities are projected to adopt the alcohol-to-jet pathway, using ethanol as a main ingredient. Additionally, according to ASTM D1655 Standard Specification for Aviation Turbine Fuels, biomass feedstocks can be co-processed with petroleum at a refinery with blends limited to 5%.

Various SAF production pathways are reviewed in DOE's Sustainable Aviation Fuel Review of Technical Pathways, which provides details on the various ASTM approved methods. Both ASTM standards are continuously updated in order to keep up with advances in technology. Currently, ASTM has approved other feedstocks, fuel molecules, and blending limits, and as these are evaluated, the types of approved fuels will increase.