US Startup Converts Cow Manure Into Jet Fuel in World-First Aviation Breakthrough

Image Courtesy: Circularity Fuels

A California clean-energy startup has successfully converted raw biogas from cow manure into sustainable aviation fuel (SAF), marking what it describes as the world’s first end-to-end demonstration of the process and potentially creating a lower-cost pathway for reducing airline emissions.

Circularity Fuels announced that it completed a six-month pilot project at a dairy farm near Madera, California, where methane-rich biogas generated from cattle manure was transformed into jet fuel that meets ASTM standards for commercial aviation. The fuel can be blended with conventional Jet-A fuel at concentrations of up to 50 percent. The milestone could significantly alter the economics of SAF production.

The pilot was conducted at a dairy operation housing more than 5,000 cattle. Using untreated biogas consisting of roughly 65 percent methane and 35 percent carbon dioxide, the system operated continuously for thousands of hours. Circularity said its technology converts farm waste directly into aviation fuel on-site, eliminating the need for extensive gas-cleaning infrastructure.

The process relies on two modular reactors. An electrified bi-reforming unit converts raw biogas into synthesis gas, while a compact Fischer-Tropsch reactor transforms that gas into liquid hydrocarbons suitable for aviation use. During testing, the company reported methane conversion rates above 98 percent and carbon dioxide conversion rates exceeding 90 percent.

The development comes as airlines and governments seek new sources of sustainable aviation fuel. Current SAF production accounts for less than one percent of global aviation fuel demand, with most supplies derived from used cooking oil. Industry experts have warned that limited feedstock availability could constrain future growth.

Circularity believes agricultural biogas offers a more scalable solution. The company estimates that commercial facilities using its technology could be built at roughly one-fifth the cost of comparable projects currently under development in Europe. It also projects installation costs below $100,000 per barrel per day of production capacity.

Founder and CEO Dr. Stephen Beaton said the key challenge was proving the technology could operate continuously using real-world farm waste rather than laboratory feedstocks. The company also claims the fuel could achieve a carbon intensity score of negative 350.7 grams of CO2 equivalent per megajoule by capturing methane that would otherwise enter the atmosphere.

Following the successful pilot, Circularity plans to begin construction of its first commercial facility in 2027, targeting agricultural regions across the United States and expanding into international markets.