Biogas-To-Jet Fuel: Circularity Fuels announces success of world’s first of its kind SAF project

American renewable fuels company Circularity Fuels has completed the world’s first end-to-end conversion of raw agricultural biogas into sustainable aviation fuel (SAF).

Over a six-month pilot run on biogas drawn straight from a California dairy farm’s manure digester, Circularity produced drop-in jet fuel meeting ASTM D7566 Annex A1 specifications. The pilot puts commercial SAF within reach at <$100,000 per barrel-per-day of installed capacity at commercial scale, about one-fifth the capital cost of SAF plants currently under construction in Europe.

The reduction in plant cost will make Circularity’s biogas-derived SAF cost-competitive with fossil jet fuel.

SAF offers a domestically produced alternative, but today’s global SAF production still meets less than 1% of demand. Agricultural biogas is one of the lowest-cost feedstocks available for SAF because almost all of it goes to waste. The world’s waste biogas resource is also vast, large enough to supply the entire global jet fuel market.

The pilot host, a dairy of over 5,000 head near Madera, California, currently vents nearly all of its biogas to the atmosphere despite sitting in the heart of the country’s largest dairy region. Circularity’s system lets operators like this one monetize that methane on-site, without the cost of removing carbon dioxide.

Over thousands of operating hours, Circularity’s two-reactor system ran on raw biogas (about 65% methane and 35% CO₂) drawn straight from the dairy’s digester and produced finished jet fuel.

The stack pairs the electrified Ouro bi-reforming reactor with the compact Aion Fischer-Tropsch synthesis reactor. Both are modular, low-cost, skid-mounted reactors, so the system is sized for the small, distributed scales at which biogas is actually produced.

“The hard part of this industry was never designing a theoretical plant that could make SAF. It was proving you could do it continuously, from real biogas, at a cost that pencils,” said Dr. Stephen Beaton, Founder and CEO of Circularity Fuels. “We’ve now done that. The full stack works end-to-end on real feedstock from a real dairy farm, and the economics put commercial SAF from dairy waste within reach of fossil jet fuel.”

Craig Hartman of Hartman Engineering, said, “Circularity is the first team I’ve seen take raw biogas straight from a digester and turn it into finished jet fuel on-site. That changes the conversation for every dairy operator we work with.”

The fuel qualifies for federal and state biofuel incentives, including the EPA’s Renewable Fuel Standard and California’s carbon-negative LCFS pathway.

With the integrated technology stack now validated in the field, Circularity Fuels is preparing for its first commercial-scale deployment. The company expects to break ground on its first commercial site in 2027, targeting agricultural biogas resources across the United States, Latin America and Europe.