Sep 19, 2025 8:00 AM Eastern Daylight Time
In PJM alone, Constellation has invested more than $5.5 billion over the past 10 years, enhancing grid reliability and adding new, clean megawatts to the grid
BALTIMORE–(BUSINESS WIRE)–During a summer of extended heatwaves and record-breaking humidity, Constellation’s emissions-free clean energy centers ran at nearly full power, further proof that nuclear is the most reliable and cost-effective energy source on the grid at a time of rising demand and increasingly volatile weather. The company’s 21 nuclear reactors at 12 sites from the Midwest to the Mid-Atlantic and Northeast collectively operated 98.8% of the time during the months of June, July and August, keeping the lights on and air conditioners humming for the equivalent of 16 million homes and businesses. Ongoing investments in these plants preserve and extend the immense and irreplaceable value they provide to the grid and society via reliable, affordable, and clean generation.
“Constellation has reinvested billions of dollars to upgrade and enhance our U.S. nuclear fleet with state-of-the-art equipment and controls, and that investment is paying huge dividends for families and businesses in the PJM, NYISO and MISO service territories,” said Joe Dominguez, Constellation President and CEO. “Like the well-known phrase about the postal service, neither snow nor rain nor heat or gloom of night will keep our team from powering America 24 hours a day 365 days a year. That is our promise; that is our commitment.”
Capacity factors are used throughout the nuclear industry to measure a reactor’s reliability and operational performance. Constellation has led the nation in capacity factors for more than a decade, producing 4% more than the industry average, which is the equivalent of having another reactor’s worth of power. In fact, all of Constellation’s 21 nuclear reactors operate at a higher capacity factor today than the year they came online.
Reliability is critical for powering the data economy, onshoring of manufacturing and electrification of transportation. In addition, Constellation is pursuing investments in equipment and technology to increase the output from its existing nuclear plants and restarting the Crane Clean Energy Center in Pennsylvania. Together, this could add up to 2,000 megawatts of new, clean and reliable baseload capacity to the grid.
Technical experts at Constellation’s nuclear facilities prepared for the extreme summer heat by performing tens of thousands of preventative maintenance tasks during spring refueling and maintenance outages designed to help all reactors run uninterrupted during the hot summer months. Each year, Constellation performs technology upgrades and installs new and enhanced equipment to ensure reliability during periods of severe weather. Unlike any other energy source, a typical nuclear plant can operate uninterrupted for up to two years without refueling, regardless of weather. These tasks are beginning anew for the fall maintenance season in preparation for increased winter demand.
Constellation’s fleet of clean energy centers in the mid-Atlantic and Northeast U.S. includes Calvert Cliffs in Calvert County, Maryland; Pennsylvania facilities Limerick and Peach Bottom in Montgomery and York counties; and New York facilities Fitzpatrick and Nine Mile Point in Oswego County and Ginna in Wayne County. Its Illinois fleet includes Braidwood in Will County, Byron in Ogle County, Clinton in DeWitt County, Dresden in Grundy County, LaSalle in LaSalle County, and Quad Cities in Rock Island County.
About Constellation
Constellation Energy Corporation (Nasdaq: CEG), a Fortune 200 company headquartered in Baltimore, is the nation’s largest producer of reliable, emissions-free energy and a leading energy supplier to businesses, homes and public sector customers nationwide, including three-fourths of Fortune 100 companies. With annual output that is nearly 90% carbon-free, our hydro, wind and solar facilities paired with the nation’s largest nuclear fleet have the generating capacity to power the equivalent of 16 million homes, providing about 10% of the nation’s clean energy. We are committed to investing in innovative technologies to drive the transition to a reliable, sustainable and secure energy future. Follow Constellation on LinkedIn and X.
Contacts
Alvin Jordan
Constellation Communications
(202) 897-9011
[email protected]