SoCalGas moves forward with dairy biomethane projects

By Southern California Gas Co. | May 17, 2019

Southern California Gas Co. (SoCalGas) announced May 16 the utility received approval from the California Public Utilities Commission to begin the next phase in construction of four new dairy biomethane projects in California.  Last week, the CPUC approved the contracts signed between SoCalGas and the developers of the four projects for the construction of infrastructure that will connect each biomethane facility to the SoCalGas pipeline system. This approval now allows SoCalGas to move forward, starting with the design and engineering phase. When completed, biogas from anaerobic digesters at 35 dairies will be collected and then cleaned to produce pipeline-quality renewable natural gas.  The new projects represent four of six pilot projects in the San Joaquinand Sacramento Valleys selected by the CPUC, the Air Resources Board and the Department of Food and Agriculture in December 2018.  These new dairy biomethane facilities will significantly reduce greenhouse gas emissions by harnessing methane emissions from dairy digesters and converting that energy into renewable natural gas (RNG) which can be used to heat homes and businesses, for cooking and to fuel trucks and buses. 

The facilities are targeted to be completed by December 2020 and combined, will have the ability to produce enough renewable natural gas to fuel close to 40,000 homes each year.   Today, there are about 37 dairy methane capture projects either operating or in development, and experts estimate there could be as many as 120 projects funded and operating in the next five years.  In addition, as the state seeks to divert organic waste from landfills and capture emissions from wastewater treatment plants, more locally produced RNG will become available.

"In the last year we began injecting RNG into the SoCalGas system through a project at an anaerobic digester in Perris and a dairy digester pipeline cluster in Pixley," said Sharon Tomkins, vice president of strategy and engagement for SoCalGas.  "We look forward to bringing these four dairy biomethane projects online as we all work to help achieve California's ambitious environmental goals."

Earlier this year, SoCalGas announced plans to offer RNG to its 21 million customers in Central and Southern California.  The program is part of the SoCalGas' overall vision to be the cleanest natural gas utility in North America.  As part of this plan, the utility committed to displacing 20 percent of its traditional natural gas supply with RNG by 2030 and replacing five percent of the traditional gas supply with RNG by 2022.

State law requires 40 percent of methane from California's dairies and other waste sectors to be captured, with provisions to deliver that energy to customers. This will bolster the supply of RNG that is already growing rapidly as cities and towns across the country look to divert organic waste from landfills. In California, scientists at the University of California, Davis estimate that the state's existing organic waste could produce enough RNG to meet the needs of 2.3 million homes.

Research shows that replacing about 20 percent of California's traditional natural gas supply with RNG would lower emissions equal to retrofitting every building in the state to run on electric only energy and at a fraction of the cost. Using RNG in buildings can be two to three times less expensive than any all-electric strategy and does not require families or businesses to purchase new appliances or take on costly construction projects.

SoCalGas recently released a broad, inclusive and integrated plan to help achieve California's ambitious environmental goals in a paper titled California's Clean Energy Future: Imagine the Possibilities. The plan embraces an all-of-the-above approach to fight climate change, keeps energy affordability as a key focus, calls for developing long-term renewable energy storage using existing infrastructure, and can aid in promoting rapid consumer adoption.  RNG is one of many tools California will need to achieve its environmental goals.

You can read SoCalGas' plan at