Northern California Utility Draws on Renewable Natural Gas

April 2, 2008

Burning natural gas is not normally seen as a use of renewable energy, but a project underway in northern California is adding a renewable dimension to this traditional fossil fuel. In early March, Pacific Gas and Electric Company (PG&E) began injecting biogas from manure into its natural gas pipeline in Fresno County. The 5,000-cow Vintage Dairy, located near the town of Riverdale, is flushing the manure from its cows into a covered lagoon that is more than three stories deep, with an area of nearly five football fields. Microbes in the oxygen-free environment of the lagoon convert the manure to methane through a process called anaerobic digestion. Methane from the lagoon is scrubbed and pressurized by BioEnergy Solutions and then injected into the PG&E pipeline. Under a long-term contract, BioEnergy Solutions plans to deliver up to 3 billion cubic feet of renewable natural gas to PG&E each year. PG&E is also investigating its own methods of generating biogas. See the PG&E press release and the BioEnergy Solutions Web site.

Aerial photo of a facility consisting of eight tall tanks, each about 40 or 50 feet in diameter and about 80 feet high, surrounded by a variety of lower tanks.

The Huckabay Ridge facility began full commercial production of pipeline-quality biogas in January.
Credit: Environmental Power Corp.

PG&E will soon be increasing its supply of renewable natural gas, according to Environmental Power Corp. (EPC). EPC is using anaerobic digestion to create renewable natural gas from manure and agricultural wastes at its Huckabay Ridge facility in Stephenville, Texas. The facility began full commercial operation in January and is expected to produce 635 billion Btu of natural gas per year, which is equal to about 616 million cubic feet. The natural gas is currently being delivered to the Lower Colorado River Authority, but as of October, it will be delivered to PG&E under a 10-year contract. See the EPC press releases on reaching commercial operation and on the PG&E contract.

While natural gas pipelines in the West are starting to carry a small amount of biogas, a proposed new pipeline in the Midwest would carry ethanol. Two petroleum pipeline companies are looking into a dedicated pipeline to carry ethanol from the Midwest to distribution centers in Ohio, Pennsylvania, and New Jersey. Magellan Midstream Partners, L.P. and Buckeye Partners, L.P. are teaming up to assess the pipeline, which could transport more than 10 million gallons of ethanol per day. See the Magellan press release and a map of the proposed pipeline (PDF 305 KB). Download Adobe Reader.