San Diego Gas and Electric and Southern California Gas Co. announced Monday the first demonstration project in California to blend hydrogen with natural gas to help reduce carbon emissions.

"Blending hydrogen with natural gas is part of a multi-pronged strategy both utilities — subsidiaries of Sempra Energy — are undertaking to decarbonize their natural gas grid," according to a joint statement. "The vision is to leverage surplus renewable electricity generated in the middle of the day to produce green hydrogen, which then can be injected into the natural gas grid for storage and use."

SoCalGas, which is working in partnership with the National Fuel Cell Research Center and UC Irvine to develop the technology, launched the first power-to-gas demonstration project in the United States in 2015.

"This hydrogen blending program is a key milestone in our efforts to decarbonize our energy system, while delivering affordable and reliable energy to 22 million California customers," said Kevin Sagara, president of Sempra Energy and chairman of SoCalGas and SDG&E.

The two subsidiaries are planning multiple hydrogen blending projects in their respective service territories. The first proposed project will blend hydrogen into an isolated section of a primarily polyethylene plastic distribution system in SoCalGas' service territory.

SoCalGas, headquartered in Los Angeles, expects to choose the location of the initial project in early 2021.

Subsequent projects are scheduled in SDG&E's service territory and will build upon the knowledge learned in the first demonstration, including blending hydrogen into an isolated section of a mixed plastic and steel natural gas distribution system, and an isolated steel pipeline demonstration.

In addition to the hydrogen blending projects, SDG&E announced in October that it intends to pilot two hydrogen projects by 2022 as part its sustainability strategy to advance carbon neutrality. Those projects would use a combination of technologies such as renewable resources, electrolysis and fuel cells to demonstrate increased system resiliency, long-duration storage, power-to-gas hydrogen fuel blending and vehicle hydrogen fueling, among other applications.

The Hydrogen Blending Demonstration Program is part of a joint application by SoCalGas, SDG&E, Pacific Gas and Electric and Southwest Gas filed with the California Public Utilities Commission.

"Green hydrogen is a game-changer, not only for our power and energy needs, but also for our industrial and transportation sectors," said state Sen. Nancy Skinner, D-Berkeley. "And green hydrogen can support existing, good- paying jobs as our state and communities take steps to transition to a zero-carbon economy."

If adopted by the CPUC, the demonstration program would provide an understanding of how to safely incorporate hydrogen, a zero-emission fuel, into the gas grid, a first step toward the establishment of a statewide hydrogen injection standard, according to the utility companies.

"Today's announcement is an exciting development for California's emerging renewable hydrogen market," said Bill Zobel, executive director of the California Hydrogen Business Council. "The Hydrogen Blending Demonstration Program will help the public understand that renewable hydrogen is important and a valuable tool for our carbon-neutral future."