Promus Energy LLC
April 17, 2019

Washington Dairy Launching Renewable Natural Gas Project with Digester

 |  By: Wyatt Bechtel

A dairy in central Washington is partnering with several energy companies in an effort to turn dairy waste into renewable natural gas that can be used for transportation.

San Francisco-based waste and energy development company, Brightmark Energy, announced the project on April 5th 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. The amount of natural gas would be equivalent to 1.4 million gallons of gasoline.

Manure will come from DeRuyter Dairies in Yakima County, Washington. The project is allowing the dairy to upgrade its 12-year-old manure collection system and digester, increasing its capacity and conserving more water.

“On day one after the digester upgrades were complete, we were out there emptying manure ponds to turn that waste back into useful products and to recycle nutrients,” said Dan DeRuyter, co-owner of DeRuyter Dairies. “We’re glad for the opportunity to lead the way for others in the industry in this arena.”

The project is expected to save DeRuyter Dairies more than $500,000 each year in operating and environmental compliance costs.

The project is being called Augean Renewable Natural Gas. Also partnering in the initiative is Promus Energy, a Washington and New Mexico based company that specializes in converting dairy waste into renewable natural gas.

The Augean project includes new pipeline infrastructure that will be constructed and also has the potential to open up the project to other dairies in the area.

As currently planned, biogas will be collected from the dairies’ anaerobic digester. The biogas would then be cleaned and upgraded before being compressed pipeline quality renewable natural gas. The gas is then transferred to the new pipeline system and injected into the nearby Williams NW regional gas transmission line for sale as vehicle fuel.

Other by-products from the Augean project include biofertilizer, digested dairy fiber for use as cow bedding or as a peat moss substitute, and reclaimed irrigation water.

“Brightmark specializes in energy technologies that turn waste into productive, sustainable energy solutions,” says CEO Bob Powell. “We are working to develop similar projects across the country to help dairy farmers mitigate the regulatory and environmental concerns associated with waste management, while transforming manure management from a cost center to a profit center.”

The project is helping reduce the carbon footprint of dairies by taking methane that might expel from a manure lagoon into a renewable natural gas. It is also helping recover nitrogen that can be utilized for fertilizer. Another advantage is the reduction in pathogens and water that would be found in lagoon water.

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 are helping support the Augean project.

“After years of working with Promus and the dairies, Yakima County is pleased to provide a matching grant for the pipeline system, which sets the stage for dairy digester projects that convert waste into value-added renewable products that improve environmental, economic, and community health,” says Mike Leita, chair of the Yakima County Board of Commissioners.

Brightmark is also working on similar biogas projects in New York, Wisconsin, Florida and Minnesota.