Ivanpah Solar Power Facility

The Ivanpah Solar Electric Generating System is a concentrated solar thermal plant located in the Mojave Desert at the base of Clark Mountain in California, across the state line from Primm, Nevada. It was slated to close in 2026, but that decision has been reversed by the California Public Utilities Commission. The facility derives its name from its proximity to Ivanpah, California, which lies within the Mojave National Preserve in San Bernardino County and which derives its name from the Chemehuevi word for "clean water".

The plant has a gross capacity of 392 megawatts (MW). It uses 173,500 heliostats, each with two mirrors focusing solar energy on boilers located on three 459-foot-tall (140 m) solar power towers. The first unit of the system was connected to the electrical grid in September 2013 for an initial synchronization test. The facility formally opened on February 13, 2014. At that time, it was the world's largest solar thermal power station.

The $2.2 billion facility was developed by BrightSource Energy and Bechtel. The largest investor in the project was NRG Energy which contributed $300 million. Google contributed $168 million. The United States government provided a $1.6 billion loan guarantee and the plant is built on federal land. In 2010, the project was scaled back from its original 440 MW design to avoid disturbing the habitat of the desert tortoise.

In January 2025, the plant’s co-owner NRG Energy announced it was unwinding power purchase agreements with Pacific Gas & Electric Company and Southern California Edison and, subject to regulatory approval, would begin closing the plant in early 2026, readying the site to potentially be repurposed for a different type of solar energy. The facility, though cost effective at the time it was planned (2009), is now twice as expensive to run as solar photovoltaic technology, which has decreased in price much more rapidly than was expected in the 15 years since Ivanpah's construction began. The power companies purchasing electricity from Ivanpah said that they expect the closure will save their ratepayers money. NRG declined to say how much of the $1.6bn loans guaranteed by the government remained unpaid as of 2025. In December 2025, the closure agreement was unanimously rejected by the CPUC.