Pixley Biogas built an aerobic digester facility to process dairy manure and food waste to create biogas for the Calgren Renewable Fuels ethanol refinery in Pixley, CA. The project met its primary goal of providing biogas to offset natural gas consumption at the ethanol refinery, thus reducing the carbon intensity of the ethanol produced. The project creates additional greenhouse gas reductions due to improved manure management.
The high score of the project application made it eligible for partial funding from the Energy Commission April 7, 2010 under grant ARV-10-053. Construction was delayed due to California Environmental Quality Act concerns raised by private parties, which were eventually satisfied. By the beginning of 2015 the facility was operating continuously and producing biogas at 131,403 standard cubic feet per day, approximately 26 percent of production capacity.
The Pixley Biogas anaerobic digester project has an exceptionally high AB-8 Benefit-Cost Score of 1,449 gCO2e for 6 months/grant dollar. It demonstrated other co-benefits such as diverting food processing wastes from the waste stream to fuel and agricultural use, and use of lower temp8erature "waste heat" from the refinery's combined heat and power plant to supply process heat for the digester. Including the Energy Commission grant funding, the project will achieve simple payback in 9.72 years.
The biogas facility constructed consists of a manure collection and transport system, a 1,400,000-gallon anaerobic digester vessel, a biogas utilization system, and a post-digester manure separation system.
