Circularity Fuels has completed what it claims is the world's first end-to-end conversion of raw agricultural biogas into sustainable aviation fuel (SAF), following a six-month pilot at a dairy farm near Madera, California.
The pilot drew biogas directly from the farm's manure digester — without prior CO2 removal — and produced drop-in jet fuel meeting ASTM D7566 Annex A1 specifications.
The system pairs Circularity's Ouro bi-reforming reactor with its Aion Fischer-Tropsch synthesis reactor, both modular and skid-mounted to suit the distributed scale at which agricultural biogas is typically produced.
The Ouro reactor achieved more than 98% methane conversion and over 90% CO2 conversion in a single electrified step.
The company says projected commercial capital costs would come in at under $100,000 per barrel-per-day of installed capacity — roughly one-fifth the capital cost of SAF plants currently under construction in Europe — putting the fuel on a potential cost-competitive footing with fossil jet fuel without subsidy stacking.
The fuel qualifies for both the EPA's Renewable Fuel Standard and California's Low Carbon Fuel Standard. Internal lifecycle modelling puts its carbon intensity at -350.7 gCO2e/MJ, reflecting the climate benefit of capturing methane that would otherwise be vented or flared.
"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. "The full stack works end-to-end on real feedstock from a real dairy farm."
Circularity Fuels says it intends to break ground on its first commercial-scale site in 2027, targeting agricultural biogas resources across the US, Latin America and Europe.
California startup completes first end-to-end conversion of dairy biogas to jet fuel
