Solar · Analysis

Ivanpah's solar towers lit the Mojave. They are going dark early.

Ivanpah's mirrors and towers were California's big bet on concentrating solar. Cheap flat panels won on price, and the plant is closing years ahead of schedule.

BY THE RENEWABLE ENERGY LA EDITORS · FILED NOVEMBER 5, 2026 · 6 MIN READ ·

How the mirrors and towers actually work

Ivanpah runs on concentrating solar power (a method that uses mirrors to focus sunlight into heat, rather than converting light straight into electricity the way panels do). About 170,000 computer-aimed mirrors, called heliostats, track the sun across the sky and bounce it onto boilers set atop three towers, each roughly 450 feet tall. The concentrated light heats water into steam, and the steam spins a turbine, the same basic machine you would find in a gas or nuclear plant.

Built by BrightSource Energy and operated by NRG, the plant opened in 2014, with Google among the early investors and a federal loan guarantee of about $1.6 billion behind it. At full output it is rated at roughly 390 megawatts, enough on a strong afternoon to register on the regional grid run by the California Independent System Operator (CAISO), which balances supply for most of the state, the LA basin included. One quirk worth knowing: it burns a modest amount of natural gas each morning to warm the boilers before the sun takes over.

Why flat panels won on price

When Ivanpah was designed in the late 2000s, concentrating solar looked like the serious way to deliver utility-scale sun. Photovoltaic panels, the flat kind that turn light directly into current, were still expensive then. Over the decade that followed, panel prices fell sharply, by something on the order of 80 percent or more at last public report, while concentrating plants stayed costly and complicated.

Mirrors have to be washed, aimed, and kept in service across square miles of desert, and the steam machinery is finicky. Ivanpah also generated less than its early projections in its first years, by most public accounts. A field of cheap panels, increasingly paired with batteries that store afternoon sun for the evening peak, now does much the same job for less money and with fewer moving parts.

What an early retirement says

The power contracts that paid for Ivanpah were long, running roughly 25 years from 2014 toward the late 2030s. In early 2025, Pacific Gas and Electric and the plant's owners said they had agreed to end two of those contracts years early, a move that needed review by the California Public Utilities Commission (CPUC), the state body that approves utility deals. Southern California Edison holds the contract for the third unit, and its plans have been quieter in public at last public report.

Retiring a plant barely a decade into a 25-year deal is unusual, and it is a plain lesson about betting everything on one way of catching the sun. The mirrors still work; the method simply lost a price race it did not expect to run. What happens next to the site, whether it is repowered with panels, left idle, or something else, is genuinely unsettled, and anyone who tells you they know for certain is guessing.

Worth watching this month

1. Watch the CPUC for any decision on PG&E's request to end its Ivanpah contracts early, which would set the real retirement timeline (this is the one that actually matters).

2. On CAISO's public supply data, see how little or how much a roughly 390-megawatt plant is missed on a hot afternoon as the units go offline.

3. Any filing about the roughly $1.6 billion federal loan is worth a look, since an early closure raises routine questions about how the debt is settled.

4. Southern California Edison has said less in public about the third unit than PG&E has about its two, so its next word there is worth catching, likely routine.

5. A proposal to reuse the Ivanpah land for photovoltaic panels or storage would be the clearest sign of which method won.

Where this dispatch reads

U.S. Energy Information Administration (EIA), www.eia.gov/electricity, Federal energy records, including plant-level generation data you can check for Ivanpah; government source.
California Public Utilities Commission (CPUC), www.cpuc.ca.gov, The state body reviewing the early end of PG&E's Ivanpah contracts; search its proceedings for the filings.
U.S. Department of Energy, Loan Programs Office, www.energy.gov/lpo/loan-programs-office, The federal office behind Ivanpah's roughly $1.6 billion loan guarantee; government source.
California Independent System Operator (CAISO), www.caiso.com, The grid operator that balances supply for most of California; public data on generation and demand.
NRG Energy, www.nrg.com, The plant's operator; company pages describe Ivanpah and its status.

Questions readers have asked

Is Ivanpah the same as the solar panels I could put on my roof?

No. Your roof panels are photovoltaic, turning light straight into electricity, while Ivanpah uses mirrors to make heat and then steam. They are two different ways of using the same sunlight.

Will this change my LADWP bill?

Almost certainly not in any direct way. Ivanpah's power was sold mainly to PG&E and Southern California Edison, not to the LA Department of Water and Power, so Los Angeles ratepayers were not paying for it directly.

Does a solar plant really burn natural gas?

Ivanpah does, in small amounts, to warm its boilers in the morning before sunlight can do the work. It is still overwhelmingly a solar plant, but it is not gas-free.

Is concentrating solar power finished for good?

Not necessarily. Newer designs store heat in molten salt to deliver power after dark, something panels cannot do on their own, so the method may still find a narrower role. For now, cheap panels and batteries have the upper hand.