THE GEYSERS GEOTHERMAL COMPLEX COMPLETES 25-MEGAWATT EXPANSION PROJECT, STRENGTHENING CALIFORNIA GRID RELIABILITY

MIDDLETOWN, Calif., June 8, 2026 /PRNewswire/ -- Calpine, a business unit of Constellation, has announced the completion of a 25-megawatt (MW) expansion project at The Geysers geothermal complex located in Sonoma County, California. The addition builds on Calpine's continued investments in The Geysers to support California's renewable energy goals and follows the completion of a 38 MW energy storage system at the site in 2024. The new capacity will generate enough electricity to power over 25,000 homes each year.

"As California's electricity demand continues to grow, investments in reliable, around-the-clock renewable energy are more important than ever," said Aimee Blaine, senior vice president of Calpine's geothermal region. "The Geysers is one of the nation's most important geothermal resources, and this expansion reflects our commitment to strengthening grid reliability while advancing California's clean energy goals."

For over 65 years, The Geysers has provided clean, geothermal energy across California. Of the 25 MW expansion, 18 MW will be directed to Clean Power Alliance (CPA), which serves customers across Southern California, providing reliable, around-the-clock renewable power as demand for clean electricity continues to grow. The remaining 7 MW, which were brought online last year, are being supplied to MCE to support Bay Area residents and businesses.

"Clean Power Alliance is committed to delivering dependable clean energy to our customers, and geothermal power plays an important role in providing around-the-clock renewable electricity," said Matthew Langer, chief operating officer, Clean Power Alliance. "Partnerships like this strengthen California's clean energy future while supporting a more resilient and sustainable grid."

The recent expansion was completed under a Project Labor Agreement (PLA) with local labor unions to build critical piping infrastructure, ensuring the work was completed by a highly skilled craft workforce under strong labor standards.

The Geysers is the world's largest operating geothermal complex, generating electricity by tapping natural steam reservoirs deep beneath the earth's surface. Geothermal energy provides an inherent environmental advantage and helps meet California's clean air goals. Geothermal power operates continuously regardless of weather or time of day, making it a critical source of baseload clean energy.

About Constellation

Constellation Energy Corporation (Nasdaq: CEG), a Fortune 200 company headquartered in Baltimore, is the largest private-sector power producer in the world and the nation's largest producer of clean and reliable energy. With 55 gigawatts of capacity from nuclear, natural gas, oil, geothermal, hydro, wind and solar facilities, our fleet has the generating capacity to power the equivalent of 27 million homes, providing about 10% of the nation's clean energy and delivering the around-the-clock reliability needed to power America's growing economy. We are also the largest nuclear energy company in the U.S. and a leading competitive retail supplier, serving approximately 2.5 million customer accounts nationwide, including 80% of the Fortune 100. We are committed to investing in innovation and new technologies to drive the transition to a reliable, sustainable and secure energy future. Follow Constellation on LinkedIn and X.

About Clean Power Alliance

Clean Power Alliance is the locally operated, not-for-profit electricity provider serving 38 communities across Los Angeles and Ventura counties. CPA is the fourth largest electricity provider in California and the number one green power provider in the United States. CPA provides clean renewable energy at competitive rates for approximately three million residents and businesses, along with innovative programs that promote resiliency, electrification and customer bill savings. CPA has an investment-grade credit rating of A from S&P Global Ratings

Contact:

Linsey Wisniewski

Constellation Communications

667-218-7700

linsey.wisniewski@constellation.com 

SOURCE Constellation