From low-carbon ethanol to dairy biogas and other advanced biofuels, our integrated facilities are providing quality fuels from today’s lowest carbon sources.
Keyes Low Carbon Ethanol
Aemetis owns and operates a 65 million gallon per year low carbon ethanol production facility located in Keyes, California. In addition to renewable fuel ethanol, the Keyes plant produces wet distillers grains, distillers corn oil, and condensed distillers solubles, all of which Aemetis sells to local dairies and feedlots as animal feed. Aemetis supplies 80 local dairies and approximately 100,000 cows with over 400,000 tons of animal feed annually. Through a partnership with Messer Gas, Aemetis also supplies over 140,000 tons of liquified CO2 to the beverage, food, and industrial sectors.
Current and planned upgrades include a [1.5 Mw size] solar microgrid with battery storage, Zebrex(C) ethanol dehydration unit, mechanical vapor recompression (MVR), and high-efficiency heat exchangers.
By converting the major processing equipment to renewable electricity, Aemetis expects to reduce the use of petroleum natural gas at the Keyes by 90% by 2025. Located above massive shale deposits, the Keyes facility is the future home to our carbon capture and sequestration facility.
Aemetis Biogas constructs biomethane anaerobic digesters at local dairies near the Keyes Plant. The digesters are connected via our private pipeline to flow dairy biogas to a gas cleanup and compression located at our ethanol plant. We completed Phase I construction in 2020, which included the first two dairy digesters and four miles of pipeline. Phase II extends this pipeline to an additional 17 dairies and adds 32 miles of private pipeline. Over 50 local dairies have signed 25-year off-take agreements and can eventually be connected by our private pipeline.
Once the biomethane from the dairies is received, we remove the impurities and convert the methane to renewable natural gas. Then we inject it into the local gas utility pipeline to service local trucking fleets or use it to power the plant.
The carbon intensity of this RNG is – 426, providing some of the lowest carbon-negative RNG available. When Phases I-III are complete, we expect to produce 450,000 MMBTU of RNG per year. When the entire network is fully built-out, we expect to produce over 1.5 million MMBTU annually.