Kern County, California – At the bottom of the San Joaquin Valley, a low midcentury building nestled among green-gold hills is the beating heart of California’s impressive water distribution system. For more than five decades, the Edmonston Pumping Plant has lifted water nearly 2,000 feet up the towering Tehachapi Mountains, providing water to 27 million people from Northern California to the southern part of the state.
The plant has 14 rumbling pumps in two football field-sized wings and is one of the most powerful water lifting systems in the world. But it could require more than 800 megawatts of power to run, making it one of the largest single power users in the state.
Now the equation is changing. On a recent weekday morning, dozens of state officials and energy industry representatives gathered at Tejon Ranch, across the street from Edmonston, to celebrate a shiny new solar plant that will help power the pumps. Calpine’s 105-MW Pastoria Solar Project, part of Constellation Energy Corporation, represents the largest renewable energy project contracted by the California Department of Water Resources and a major step forward in its planning. Fully decarbonized operations by 2035, In accordance with state law.
“The majority of Californians – as many as 1 in 12 Americans – get their water from the state water project,” said DWR Director Carla Nemeth. “To make that system carbon neutral by 2035, we need efforts like the Pastoria Solar Project. When we achieve our clean-energy goal while continuing to supply water without interruption, we will set a standard for other public agencies across America.”
The pumping plant receives its power from California’s main electrical grid, and will continue to do so. But the Water Department has signed a contract to take solar power produced by the plant, which is a common and recognized way for agencies and companies to clean up their electricity supplies.
Employees inspect the battery storage system during a tour of Pastoria facilities.
The new Pastoria project is about two miles from the pumps. Its 226,000 solar panels are mounted on a 500-acre parcel and feed into a substation on the property. Although the electricity does not choose its path, officials said the electricity generated nearby meets the demand in the neighborhood.
The solar plant is located next to a soon-to-be-built 80-MW/320-MWh battery storage bank and Calpine’s existing 750-MW natural gas-fired combined-cycle generation plant, which company officials have described as a “trifecta” of energy reliability. A four-hour battery will help bridge the gap during hours when the sun doesn’t shine, while the gas-and-steam plant will make up the rest.
“By co-locating solar, battery storage and a highly efficient natural gas combined cycle plant, we are able to provide critical services at a key point on the transmission system while supporting California’s long-term energy goals,” said Andrew Novotny, Calpine president and chief executive.
The Water Department has signed a 20-year power purchase agreement for the solar plant at the rate of $1 per megawatt hour. Pacific Gas & Electric signed a 15-year agreement for the battery bank at a rate that was not disclosed.
The project comes as California and the nation grapple with rising energy demand due to the rise of artificial intelligence data centers, increasing pressure on a grid already burdened by extreme heat and aging infrastructure.
It also comes as the Trump administration moves to roll back federal climate regulations and accelerate fossil fuel production. The President made an announcement last year end of federal tax credits for commercial solar projects, which he described as “expensive and unreliable”. Pastoria is slipping right under the wire, as construction on the projects should begin by July or be up and running by the end of next year.
But officials said projects like Pastoria offer a path for California to rapidly add more power while staying on track with clean energy goals: About half of the State Water Project’s energy needs can be met by its own hydropower, but the other half will have to come from Pastoria and similar efforts, said John Yarbrough, deputy director of the State Water Project. This also includes another Kern County solar project, 100 MW, coming online next year Kyan Solar Project.
Pastoria Tiburius Substation at the facilities in Arvin.
“We have a front row seat to seeing the impacts of our changing climate,” Yarbrough said. “It really gives us a vested interest in doing whatever we can to protect the state and mitigate the causes of climate change.”
Yarbrough said the primary benefit of the Pastoria solar project is not monetary savings, but decarbonization, as climate change resulting from fossil fuel emissions is already creating greater unpredictability for California’s hydropower. In fact, the project is likely to increase water costs for contractors purchasing water from the State Water Project.
That has caused some unease among agencies, according to Jonathan Young, energy manager for State Water Contractors, a nonprofit that represents 27 water agencies in California, including the vast Metropolitan Water District that serves Los Angeles.
Young said, “Generally, we support the direction DWR is going, but there are concerns that there will be an impact on costs.” The group estimates that DWR’s decarbonization efforts will cost its members $1.5 billion by 2045.
He said these costs would fall heavily on ratepayers, although it was not yet clear how much the Pastoria project alone would add to people’s water bills.
The Pastoria Energy Facility is located beneath the Arvin Hills in Kern County.
(Eric Thayer/Los Angeles Times)
But Young said water agencies also recognize the need to address climate change — and building these projects now may be the last opportunity to take advantage of cost savings before the federal tax credit expires.
“Ultimately, this is an additional cost on our members, and it creates many other affordability challenges,” he said. But they care most about reliable water delivery, so “if it means our members can still get and deliver water to producers and cities, so be it.”
Others, including Molly Sterkel, director of electric supply, planning and cost at the California Public Utility Commission, were optimistic about the project. He said projects like Pastoria show that the state’s clean energy plans are achievable and “aren’t just on paper.”
“These are really important – they’re demonstrating that these targets are credible,” she said. “Every year, as we’re reducing our greenhouse gas emissions, we’re improving our air quality.”
Sterkel told the crowd in front of gleaming solar panels that California has brought 31,000 megawatts of new clean energy resources online by 2020, and is set to bring 22,000 megawatts of newly contracted resources online by 2030.
“This project is real,” she said, “and it is part of a wave of historic clean energy development in California.”
