NEW YORK, Sept 25 (Reuters) - Fully decarbonizing California's electrical grid will require more firm clean power sources, including advanced geothermal and natural gas with carbon capture, Edison International (EIX.N) , opens new tab chief executive officer told Reuters on Wednesday.

The most populous U.S. state has set a goal to produce zero net emissions from its electrical grid by 2045, with renewable energy sources solar and wind playing the starring role in California's power generation plans.

"We need not just clean power, we need power that can meet demand every single minute of the day," said Pedro Pizarro, head of the major power company whose largest subsidiary is Southern California Edison, an electric utility covering about 15 million people.

Using entirely solar, which California uses more than any other U.S. state, and wind alone wouldn't provide enough around-the-clock power or be logistically realistic, he said.

In order to hit its goals, the state would need to add 120 gigawatts of renewables with storage between now and its target date.

"The challenge is that if we were to meet all of California's needs with just solar and storage, we would need to blanket an area the size of the entire Los Angeles metropolitan area with solar," Pizarro said.

Southern California Edison this year entered into a 320 megawatt power purchase agreement with geothermal provider Fervo in a largest-of-its kind contract for geothermal. The contract enables Fervo to finance its power generation build-out, with the electricity to be phased in starting in 2026 and ramp up through 2028.

In the time between adding enough clean power in California, Pizarro called for the state's natural gas-fired power plants to be preserved to keep power flowing.

"We have an insurance policy in California that's our existing gas generation fleet," Pizarro said, adding that Southern California Edison doesn't sell natural gas, which release global warming carbon emissions.

Multiple natural gas-fired power plants along the California coast were slated to shut in 2020 under climate plans, but state officials extended their lifespan until 2026 to avoid power shortfalls that could cause blackouts.

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https://www.reuters.com/business/energy/more-firm-clean-power-needed-hit-california-climate-goals-edison-intl-ceo-says-2024-09-25/