L.A. Kicks Coal As It Fires Up The World’s Largest Green Hydrogen Power Plant

December 4, 2025

Los Angeles has officially stopped using electricity generated from coal and is about to fire up the first large-scale plant making power from both green hydrogen and natural gas as the second-largest U.S. city works to get all of its energy from carbon-free sources by 2035.

“I can officially say that Los Angeles is no longer powered by coal-fueled energy,” Mayor Karen Bass said at a briefing on Thursday, joined by the head of LADWP, the country’s biggest municipal utility, and other officials. “Last week, the Intermountain Power Project in Utah delivered the last coal-fueled energy to our city.”

Starting in January, that same facility in Delta, Utah, will instead send electricity to Los Angeles generated from turbines powered by combusting a blend of natural gas and hydrogen. Initially, the goal is to run a mix of 70% gas and 30% hydrogen. But over time, the city-owned utility plans to transition to 100% hydrogen, made from water and renewable power on site and stored in a vast underground salt cavern adjacent to the plant, said David Hanson, who manages power projects for the Los Angeles Department of Water and Power.

“We’ve used the Intermountain Power Project since the 1980s. It’s built on top of a salt cavern. They knew it all along, but no one really cared,” Hanson told Forbes. The utility’s partners in the project are already making hydrogen and storing it in the cavern, which Hanson said is about the size of the Empire State Building. “It makes an excellent, leak-proof storage place for hydrogen.”

The Intermountain Power Project, which previously generated electricity for Los Angeles from coal, has been modified to make it from hydrogen and natural gas.

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It’s the single largest green hydrogen project “in the world, and it’s operational now,” he said.

L.A.’s power experiment comes at a time when the outlook for carbon-free green hydrogen, at least in the U.S., has dimmed. It’s more expensive to produce compared to making industrial hydrogen by splitting natural gas, which is cheap but produces large amounts of byproduct carbon pollution. The Trump administration also hasn’t been supportive, cancelling federal funding for so-called hydrogen hubs in California and the Pacific Northwest that were intended to improve large-scale production and use of clean hydrogen.

Still, L.A.’s project has been in the works since 2022, when it won a $504 million loan guarantee from Biden’s Energy Department for the Utah facility, with its equipment already installed and running. Its electrolyzers which split water, a process that releases only oxygen as a byproduct, were supplied by the U.S. arm of Mitsubishi Power and sourced from China, said Kevin Peng, an LADWP project director.

“At the scale we were building – 220 megawatts – there was no facility anywhere in the United States that could supply them,” he said. When the first phase is fully operational, the system will produce 21 million kilograms of hydrogen a year.

When hydrogen is used in a fuel cell to make carbon-free electricity, such as in spacecraft or cars like Toyota’s Mirai sedan, water is the only byproduct. When burned, however, it produces water as well as nitrogen oxides (NOx), an air pollutant. But LADWP is convinced that conventional pollution-filtering systems already used at natural gas power plants can handle it.

“There’s a misconception around how much emissions actually come out of hydrogen,” Peng said. The Utah plant will use the latest selective catalytic reduction systems to keep NOx and all the other emissions “way below permitting limits. Plus, we get the added benefit of zero CO2,” he said.

And that’s the city’s ultimate goal, Bass said. “In 2003, L.A.’s energy supply was 3% renewable energy and over 50% coal,” she said. “Today, just over 20 years later, our city is powered by 60% carbon-free energy and again, 0% coal.”