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

Rhea-AI Summary

Constellation (CEG) business unit Calpine completed a 25 MW expansion at The Geysers geothermal complex in Sonoma County, California, enhancing baseload renewable capacity and grid reliability.

Of the added capacity, 18 MW serves Clean Power Alliance and 7 MW supplies MCE customers.

Positive

• Added 25 MW of baseload geothermal capacity at The Geysers
• 18 MW of new capacity contracted to Clean Power Alliance in Southern California
• 7 MW of new capacity supplying MCE customers in the Bay Area
• Expansion follows completion of a 38 MW energy storage system in 2024
• Project completed under a Project Labor Agreement with local skilled labor

Negative

• None.

News Market Reaction – CEG

-1.63%

-1.63% Session close to close

In the Jun 8 session, CEG declined 1.63%, reflecting a mild negative market reaction.

Data tracked by StockTitan Argus on the day of publication.

Market Context

This announcement highlights the completion of a 25 MW geothermal expansion at The Geysers, adding e...

Analysis

This announcement highlights the completion of a 25 MW geothermal expansion at The Geysers, adding enough power for over 25,000 homes and building on a 38 MW storage system finished in 2024. It reinforces Constellation’s post-Calpine focus on clean, around-the-clock generation. Investors may watch how this fits alongside recent secondary share activity, ongoing integration of acquired assets, and future project additions under the existing growth and financing framework.

Key Figures

Geothermal expansion: 25 MW Energy storage system: 38 MW Homes powered: over 25,000 homes +3 more

6 metrics

Geothermal expansion 25 MW Capacity added at The Geysers geothermal complex

Energy storage system 38 MW Energy storage system completed at The Geysers in 2024

Homes powered over 25,000 homes Annual electricity from new 25 MW capacity

Capacity to CPA 18 MW Portion of expansion directed to Clean Power Alliance

Capacity to MCE 7 MW Portion of expansion supplied to MCE

Operating history over 65 years The Geysers providing geothermal energy across California

Historical Context

5 past events · Latest: Jun 01 (Negative)

Pattern 5 events

Date	Event	Sentiment	24h Move	Catalyst
Jun 01	Secondary offering priced	Negative	-7.7%	Pricing of 11,000,000-share secondary at $281.00 by selling shareholders.
Jun 01	Secondary offering announced	Negative	-7.7%	Announcement of 11,000,000-share secondary and planned 2,000,000-share buyback.
May 14	RNG equity investment	Positive	+0.1%	Minority equity purchase in five Pine Creek RNG facilities and growth framework.
May 11	Q1 2026 earnings	Positive	-1.3%	Strong EPS growth and affirmed 2026 guidance with several new projects.
May 07	Board nomination news	Neutral	-3.6%	ONE Nuclear Energy announced director nominees tied to a business combination.

24h Move is the share-price change in the day after each event; other market factors may also have contributed.

Pattern Detected

Recent negative reactions followed secondary offering headlines, while strong earnings and strategic growth news have sometimes seen muted or negative price responses.

Recent Company History

In the last month, Constellation announced a large secondary offering of 11,000,000 existing shares with a $281.00 offer price, which coincided with a -7.66% move, and later filed related 8-K and 424B4 documents. Earlier, the company reported sharply higher Q1 2026 earnings, affirmed $11.00–$12.00 guidance, and highlighted major generation additions, yet the stock fell 1.3%. Smaller strategic deals like the Pine Creek RNG equity purchase saw flat price impact. Against this backdrop, today’s geothermal expansion extends the post-Calpine growth narrative.

Key Terms

geothermal energy, energy storage system, project labor agreement, baseload

4 terms

geothermal energy technical

"The Geysers has provided clean, geothermal energy across California."

Geothermal energy is heat drawn from beneath the Earth’s surface and converted into electricity or used directly for heating, like tapping a giant, naturally heated underground oven to run a power plant or warm buildings. It matters to investors because geothermal projects are capital-intensive up front but can deliver steady, low-cost power and long-lived income streams with low fuel risk; however, they carry exploration, drilling and permitting risks that affect returns.

energy storage system technical

"follows the completion of a 38 MW energy storage system at the site in 2024."

An energy storage system is a setup that captures electricity when supply is abundant and stores it for later use, using batteries, pumped water, compressed air, or other methods. It matters to investors because it helps smooth power supply like a home battery preventing outages, lets renewable generation be sold when prices are high, can lower system costs and create new revenue streams, and therefore influences a company’s profitability, growth prospects and regulatory exposure.

project labor agreement technical

"The recent expansion was completed under a Project Labor Agreement (PLA) with local labor unions"

A project labor agreement is a pre-arranged contract between a project owner and labor unions that sets the wages, benefits, hiring rules, work schedules and dispute processes for a specific construction project. It acts like a rulebook for the workforce, aiming to prevent strikes and ensure predictable staffing. Investors care because it makes labor costs and timing more predictable, can limit contractor choice, and therefore affects project budget, pace and risk.

baseload technical

"making it a critical source of baseload clean energy."

Baseload is the minimum, steady level of electricity demand or supply that exists over a typical day or season, like the baseline heartbeat of the power grid. Investors care because assets that reliably meet baseload — such as certain power plants or long-term contracts — provide predictable revenue and lower risk, while shortfalls or oversupply at this level can drive price swings and affect valuations.

AI-generated analysis. How Rhea-AI works. Not financial advice.

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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 

View original content:https://www.prnewswire.com/news-releases/the-geysers-geothermal-complex-completes-25-megawatt-expansion-project-strengthening-california-grid-reliability-302793766.html

SOURCE Constellation

FAQ

What did Constellation (CEG) announce about The Geysers on June 8, 2026?

Constellation announced Calpine completed a 25 MW expansion at The Geysers geothermal complex, boosting renewable baseload capacity. According to Constellation, the project supports California’s clean energy goals and strengthens grid reliability as electricity demand grows across the state.

How much new power will The Geysers 25 MW expansion provide for California customers of CEG?

The 25 MW expansion will generate enough electricity to power over 25,000 homes each year. According to Constellation, 18 MW serves Clean Power Alliance customers and 7 MW supports MCE customers in the Bay Area with around-the-clock renewable energy.

Which utilities benefit from Constellation’s 25 MW geothermal expansion at The Geysers?

Clean Power Alliance receives 18 MW and MCE receives 7 MW from the 25 MW expansion. According to Constellation, these deliveries provide reliable, around-the-clock geothermal power to Southern California and Bay Area customers as demand for clean electricity continues to grow.

How does The Geysers expansion support grid reliability for Constellation (CEG) and California?

The expansion adds continuous, weather-independent geothermal baseload capacity to the California grid. According to Constellation, geothermal power at The Geysers operates around the clock, helping meet rising demand while advancing the state’s renewable and clean air goals.

What construction approach was used for Constellation’s new geothermal capacity at The Geysers?

The expansion was built under a Project Labor Agreement with local labor unions. According to Constellation, this ensured critical piping infrastructure was installed by a highly skilled craft workforce working under strong labor standards for the geothermal complex.

How does The Geysers geothermal complex fit into Constellation’s clean energy portfolio?

The Geysers is described as the world’s largest operating geothermal complex and has supplied clean power for over 65 years. According to Constellation, it provides inherent environmental advantages and critical baseload clean energy regardless of weather or time of day.