The aviation industry in the United States, responsible for about 2% of the nation’s annual carbon emissions, is a focal point for decarbonisation efforts. Among the emerging solutions is the production of sustainable aviation fuel (SAF) from waste, which offers a promising avenue to reduce the sector’s carbon footprint. Researchers are now showing that the U.S. generates enough waste to produce a commercially viable amount of SAF, signalling a transformative shift for the future of aviation fuel.
The Pacific Northwest National Laboratory (PNNL) has been at the forefront of exploring waste-to-fuel technologies. By converting household garbage, sewage sludge, and agricultural plant residues into biocrude oil, these materials can be refined into SAF. In a recent study funded by the U.S. Department of Energy’s Bioenergy Technologies Office, researchers at PNNL have begun identifying the optimal sites for waste-to-fuel SAF production facilities across the country.
The study, Cost-Effective Opportunities to Produce Sustainable Aviation Fuel from Low-Cost Wastes in the U.S., focused on co-locating SAF production facilities near significant waste sources and major airports, which are heavy consumers of jet fuel. Wet waste, such as manure and sludge, and dry waste, like food scraps and yard debris, tend to accumulate in densely populated areas. Coincidentally, large airports near these population centres consume enormous volumes of jet fuel. For instance, the top five airports in the U.S. each burn through more than a billion gallons of jet fuel annually.
By producing SAF closer to where both waste and jet fuel demand are highest, researchers believe the cost of transportation can be reduced, further improving the economic viability of SAF. For example, a SAF facility near Los Angeles, a city with lower usable waste levels, could replace 7% of the fuel used at Los Angeles International Airport (LAX). Conversely, a facility near Chicago’s O’Hare International Airport, where more waste is available, could replace up to 22% of the airport’s annual jet fuel with SAF.
The PNNL study suggests that with fewer than 100 waste-based SAF refineries located at or near airports, the U.S. could replace between 15% and 25% of its annual jet fuel supply. Despite this promising outlook, scaling the production of SAF remains a challenge. Cost-competitiveness with traditional fuels is a hurdle, and the limited availability of usable waste constrains the extent to which SAF can replace conventional jet fuel. Moreover, researchers are working to ensure that waste-to-fuel facilities do not negatively impact surrounding communities.
Still, the move toward SAF derived from waste marks a significant step forward in the aviation industry’s decarbonisation efforts. With continued research and technological advancements, waste-to-fuel SAF could become a key contributor to a more sustainable future for aviation, diverting waste from landfills and reducing the carbon intensity of air travel.
For further insights into the study on waste-to-fuel SAF production, see the full report published in ACS Sustainable Chemistry & Engineering
Dr. Karthikeyan K. Ramasamy: A Key Contributor
Dr. Karthikeyan K. Ramasamy, Chief Chemical Engineer at PNNL, has been instrumental in advancing the development of renewable chemicals, marine fuels, and SAF. His work is focused on creating heterogeneous catalysts for converting various biomass sources into sustainable fuels. Dr. Ramasamy also serves as the Laboratory Relationship Manager for the U.S. Department of Energy Bioenergy Technologies Office, overseeing research on the sustainable use of biomass for fuel production.
