Brightmark Energy, a San Francisco, California-based waste and energy development company, recently launched a biogas project in Yakima County, Washington, that will convert 150,000 gallons per day of dairy waste from up to 7,000 cows into 160,000 MMBtu of renewable natural gas (RNG) – the equivalent of 1.4 million gallons of gasoline – and other products each year.
Courtesy of Brightmark Energy
Collaborating as Augean Renewable Natural Gas (RNG), Brightmark Energy, Promus Energy, and DeRuyter Dairies developed the project. Brightmark Energy will manage the joint venture and Promus Energy, the original developer, will serve as the project manager.
A key component of the Augean project is the construction of new pipeline infrastructure by Yakima County and Augean that sets the table for RNG projects for other dairies in the area. The Augean project will collect biogas from DeRuyter’s anaerobic digester fueled exclusively by manure. The raw biogas will be cleaned, upgraded, and compressed into pipeline quality RNG, which will be transported through the new pipeline system and injected into the nearby Williams NW regional gas transmission line for sale as vehicle fuel. In addition to RNG, other renewable products generated by Augean’s anaerobic digestion process include biofertilizer, digested dairy fiber for use as cow bedding or as a peat moss substitute, and reclaimed irrigation water.
Brightmark’s investment in the Augean project enables DeRuyter to upgrade its 12-year-old manure collection system and digester to increase its capacity and conserve water. DeRuyter anticipates that the project will save the dairies more than $500,000 each year in operating and environmental compliance costs.
Dairy-derived RNG is a low carbon intensity transportation fuel that benefits the local environment by processing and recovering much of the nitrogen in manure as a value-added biofertilizer. The biofertilizer can be efficiently transported to crop fields that need the nitrogen and other nutrients, displacing chemical fertilizers and creating a sustainable cycling of nutrients that prevents water and air pollution. Other advantages include the drastic reduction of pathogens and odor in the process water and products recovered from the system.
The Augean biogas project is also supported by a $1.4 million grant from Yakima County and a $500,000 Rural Energy for American Program (REAP) grant from the U.S. Department of Agriculture