Sustainable Aviation Fuels
The commercial aviation sector is expected to grow significantly through 2050. The sector, which is committed to carbon neutral growth, will continue to need energy-dense, liquid transportation fuels for the foreseeable future . Sustainable aviation fuels (SAF) derived from renewable and waste carbon resources have the potential to satisfy this demand while reducing the life-cycle greenhouse gas emissions (GHG) compared to fossil-derived jet fuel. The International Civil Aviation Organization (ICAO) defines SAF as alternative aviation fuels that (i) achieve net GHG emissions reduction on a life cycle basis; (ii) respect the areas of high importance for biodiversity, conservation and benefits for people from ecosystems, in accordance with international and national regulations; and (iii) contribute to local social and economic development, and competition with food and water should be avoided. These fuels can be utilized in existing jet engines, some at blends of up to 50%, with no changes in fuel storage, distribution, and engine systems.
Sustainable Aviation Fuel Research at the U.S. Department of Energy (DOE)
DOE’s Office of Energy Efficiency and Renewable Energy (EERE) Bioenergy Technologies Office (BETO) is conducting research, development and scale-up activities on renewable feedstocks and innovative conversion technologies that can produce low carbon intensity SAF. Feedstocks of interest include terrestrial biomass (agricultural residues, forestry residues, energy crops), micro-algae, urban wood waste, municipal solid waste, wet wastes (sewage sludge, animal manures, food waste), gaseous wastes (steel manufacturing and refinery off-gases), and carbon dioxide. A variety of feedstock pre-processing and conversion technologies are being investigated including biochemical, thermochemical, electrochemical, and hybrid approaches. BETO is focused on drop-in renewable jet fuel that can integrate into existing fuel storage, transport, airport hydrant, and jet engine systems with minimal disruption.
BETO is currently funding several industry-led projects selected through competitive funding opportunities. Projects include:
- Applied Research Associates, Inc.’s (ARA) efforts to develop a developing a new production pathway for Catalytic Hydrothermolysis Jet
- Fulcrum Bioenergy’s Sierra BioFuels Project
- Lanzatech’s work to produce jet fuel from recycled waste carbon, resulting in the world’s first commercial flight using SAF
BETO is also funding a multi-laboratory consortium that is developing conversion technologies at laboratory scales. Jet consortium members include, Sandia and Pacific Northwest National Laboratories (SNL and PNNL), the National Renewable Energy Laboratory (NREL). work includes the following activities:
- Sandia to develop JP-10
- NREL developing waste-based feedstocks ketonization of volatile fatty acids followed by catalytic upgrading to renewable jet
- PNNL developing alcohol-to-jet process with Lanzatech
- Hydrothermal liquefaction of wet wastes with biocrude upgrading to jet
BETO coordinates SAF activities across the Federal government through participation in a SAF Interagency Working Group, established under the Biomass R&D Board. The SAF Interagency Working Group comprises FAA, USDA, DoD, NASA, EPA, and other Federal government agencies.
Select Sustainable Aviation Fuel Reports
- U.S. Airport Infrastructure and Sustainable Aviation Fuel, 2021, The National Renewable Energy Laboratory
- Sustainable Aviation Fuels: Review of Technical Pathways, 2020, U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy
- U.S. Alternative Jet Fuel Deployment Scenario Analyses Identifying Key Drivers and Geospatial Patterns for the First Billion Gallons, 2018, Biofuels, Bioproducts, and Biorefining
- Alternative Aviation Fuels: Overview of Challenges, Opportunities, and Next Steps, 2017, U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy
- Potential Avenues for Significant Biofuels Penetration in the U.S. Aviation Market, 2017, The National Renewable Energy Laboratory
- Well-to-wake Analysis of Ethanol-to-jet and Sugar-to-jet Pathways, 2017, Biotechnology for Biofuels
- Bio-jet Fuel Conversion Technologies, 2016, Renewable and Sustainable Energy Reviews
- An Overview of Aviation Fuel Markets for Biofuels Stakeholders, 2014, The National Renewable Energy Laboratory