Geysers geothermal field – Enviro Updates

New 25-megawatt Geysers geothermal plant comes fully online

June 22, 2026

Jeff Quackenbush, NORTH BAY BUSINESS JOURNAL

“Despite rapidly rising demand for renewable energy and the abundance of geothermal resources in California, geothermal power generation is declining,” the [CEC] report said.

Calpine Corp. has completed a 25-megawatt expansion at The Geysers geothermal area in the North Coast, increasing the amount of around-the-clock renewable electricity available to California communities and supporting growing demand for reliable clean energy.

The project adds enough generating capacity to power more than 25,000 homes annually and follows Calpine’s completion of a 38-megawatt energy storage system at the underground steam field in 2024.

The Geysers, which spans Sonoma and Lake counties, is the world’s largest operating geothermal complex and has supplied energy to California for more than 65 years. Houston-based Calpine, now part of Constellation Energy, is the largest operator at The Geysers, with 13 power plants there. Output from all plants in the field averages more than 700 megawatts.

Constellation Energy completes $26 billion acquisition of Calpine, major operator at The Geysers

January 26, 2026

Jeff Quackenbush, NORTH BAY BUSINESS JOURNAL

But Earthjustice, together with Public Citizen, PennFuture and Clean Air Council, petitioned federal regulators to block the combination, claiming it would increase electricity costs by reducing competition and it would increase pollution via the natural gas plants.

The biggest operator of geothermal power plants at The Geysers field straddling Sonoma and Lake counties is now under new ownership.

Constellation Energy Corp. (Nasdaq: CEG) has finished its $26.6 billion acquisition of Calpine Corp., which has been involved with The Geysers 36 years ago and expanded its holdings to become its top producer a decade later.

The transaction, originally announced a year ago and completed early this year, finalizes one of the largest power-generation deals in U.S. history and creates what the company describes as the nation’s top producer of electricity.

It brings together Baltimore-based Constellation’s zero-emission nuclear fleet with Houston-based Calpine’s natural gas and geothermal assets, positioning the combined company to meet rapidly rising power demand driven by data centers, artificial intelligence, advanced manufacturing and electrification. They collectively serve about 2.5 million customers nationwide and operate 55 gigawatts of capacity across nuclear, natural gas and geothermal resources.

Climate Change & EnergyCalpine, Constellation Energy, geothermal, Geysers geothermal field

Next-gen geothermal power sees early results at The Geysers

June 14, 2025

Jeff Quackenbush, NORTH BAY BUSINESS JOURNAL

“This is a breakthrough — not just for our team, but for the future of geothermal,” said Rob Klenner, president of GreenFire Energy..”

California’s goal of producing more round-the-clock power from The Geysers may be in reach, as a demonstration there of next-generation geothermal energy technology has become operational and is said to be generating promising early results.

The project is part of a multipronged effort to increase electrical output for the North Bay and throughout California from what’s still the world’s largest geothermal energy field despite declining steam production at the plants in the Mayacamas range between Sonoma and Lake counties.

Oklahoma City-based GreenFire Energy last month announced that its first commercial demonstration system, installed in a low-output well at The Geysers, is now fully operational. The well, previously nearing idle status, is producing sustained flow rates of 300–350 gallons per minute with unexpectedly high-output temperatures of 310 degrees Fahrenheit, all within a closed-loop system.

GreenFire’s patented “GreenLoop” system relies on pipe-enclosed fluid that goes down into the well cool, gets heated then comes back up to release the heat into a electricity-generation system. This fluid has a lower boiling point than water, requiring less heat to produce steam.

Climate Change & Energygeothermal, Geysers geothermal field

Op-Ed: Looking locally for renewable energy

May 13, 2025

Geof Syphers, PRESS DEMOCRAT

As the new federal administration’s policies begin to unfold, it’s clear that real climate solutions will primarily be driven at the local level. It’s also clear that shifting from fossil fuels toward renewable electricity is made more difficult in California because of our sky-high electric rates. Community-owned power providers like Sonoma Clean Power are tackling both challenges — climate change and cost.

One way Sonoma Clean Power works to keep electric bills in check is by advocating at the California Public Utilities Commission for more effective wildfire prevention expenditures. We believe PG&E should focus on the most critical repairs first, not the easiest or most lucrative. We also believe PG&E needs to better justify any new rate increases, which is why we’ve started carefully checking their math. By advancing solutions to make rates reasonable, we can help everyone afford the switch to electric appliances and vehicles.

Los Angeles Times columnist Sammy Roth suggested shifting the expense of undergrounding power lines from electric bills to the state’s general fund. Such a move could lower overall costs for both low-income and most middle-income customers, making electric appliances more appealing and helping us reduce fossil fuel use faster. Sonoma Clean Power is studying how to make this approach viable, because affordable rates are essential for speeding up climate progress.

Climate Change & Energyemissions reduction, geothermal, Geysers geothermal field, renewable energy

Geothermal expansion effort at The Geysers seeks help from California lawmakers on speeding up permits

March 17, 2025

Jeff Quackenbush, NORTH BAY BUSINESS JOURNAL

California’s effort to generate much more round-the-clock clean energy from geothermal resources such as The Geyers area straddling Sonoma and Lake counties seems to be running out of steam because of the state’s permitting system.

One of the three initial partners in the geothermal opportunity zone (GeoZone) effort promoted by Sonoma Clean Power has acquired its first parcel of land, known as Pocket Ranch.

However, the permitting process in California is proving to be a significant obstacle for Chevron New Energies to move forward with finding out what potential there is for next-generation geothermal technologies that aim to generate more energy using far less water.

“They are putting that into a slow-moving process, because they’re finding that California’s permitting process for the exploratory phase is adding too much cost and risk relative to all the other western states,” said Geof Syphers, CEO of Sonoma Clean Power, the public electricity supplier for Sonoma and Mendocino counties, that draws a portion of its renewable power from The Geysers.

Climate Change & Energygeothermal, Geysers geothermal field, legislation, permitting

Constellation Energy nears $30 billion deal for Calpine, major player in Geysers geothermal

January 9, 2025

Ryan Gould, Dinesh Nair, Matthew Monks and David Carnevalli, BLOOMBERG

Constellation Energy Corp. is nearing an acquisition of Calpine Corp., people familiar with the matter said, in what would be one of the biggest ever deals in the power generation sector.

Baltimore-based Constellation is in discussions with Calpine’s private equity owners about the terms of a transaction that could value the company at about $30 billion including debt, according to the people. A deal may be announced in the coming weeks, they said.

Calpine operates the majority of power plants in The Geysers geothermal field straddling Sonoma and Lake counties in the Mayacamas mountains.

Climate Change & EnergyCalpine, Constellation Energy, electricity, Geysers geothermal field, renewable energy