Newsroom: Press Release

Major upgrades at Constellation nuclear stations ensure carbon-free electricity for 15 million this summer

Over 13,000 workers supported maintenance projects during spring refueling outages to keep power supplied 24/7 during hot summer months and beyond


WARRENVILLE, Ill. (June 10, 2022) — Over 13,000 workers performed technology upgrades and equipment maintenance during six refueling outages at Constellation nuclear plants this spring, investments that will prepare the plants for the hot summer months ahead. The cutting-edge upgrades and preventive maintenance will ensure Constellation’s nuclear fleet, which serves 15 million American homes and businesses, will have access to safe, affordable, carbon-free electricity this summer to help combat any periods of high heat or humidity.

During the refueling outages, workers replaced or refurbished dozens of pumps and motors, performed quality assurance inspections on reactor and fuel components, and completed tens of thousands of other technical tasks to ensure the power plants provide uninterrupted carbon-free electricity for up to 24 straight months.

“Constellation is helping accelerate this country’s transition to a carbon-free future and it begins with our zero emissions nuclear fleet running nonstop through the summer,” said Joe Dominguez, CEO of Constellation. “We met our commitment to operational excellence last winter by keeping our plants running throughout the cold months despite challenging weather conditions. Our investments in the plants this spring will help us maintain that level of performance during the upcoming summer months, as the climate crisis continues to produce extremely hot weather.”

This summer, nuclear reliability could be especially helpful in moderating electricity prices for Illinois customers. Constellation’s 24/7 carbon-free baseload nuclear power displaces generation from fossil-fuel plants that may experience further spikes in gas and oil costs. This is in addition to the $1 billion credit Constellation’s nuclear plants are projected to deliver for northern Illinois ratepayers as a result of the Climate & Equitable Jobs Act passed last year.

The refueling outages would not be possible without support from thousands of skilled electricians, pipefitters, welders, carpenters, laborers, steamfitters and other trades people on site performing thousands of inspections, tests and maintenance activities that cannot be done while the unit is online. Along with replacing about one-third of the fuel in each reactor, workers completed other major projects during the nuclear outages this spring, including:

  • In Illinois, workers at Quad Cities Unit 2 performed an overhaul and inspection of the turbine on one of the redundant core cooling systems; a full technical inspection of the Byron Station Unit 2 main generator; and a comprehensive inspection of two reactor recirculation flow control valves at LaSalle County Generating Station.
  • In the east, workers at Calvert Cliffs Station in Maryland replaced the Unit 1 main generator connections. At Limerick Station in southeastern Pennsylvania, technical experts performed a full inspection of the main turbine. At Nine Mile Point in upstate New York, workers replaced all four of the Unit 2 main power transformers, improving the station’s ability to maintain safe, reliable, carbon-free power for the upstate New York area.

“We carefully schedule these important upgrades, maintenance activities and technical inspections during periods of lower power demand to ensure our carbon-free nuclear units remain online 24/7 through the blistering summer months ahead,” said Tim Hanley, chief operating officer at Constellation.

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About Constellation

A Fortune 200 company headquartered in Baltimore, Constellation Energy Corporation (Nasdaq: CEG) is the nation’s largest producer of clean, carbon-free energy and a leading supplier of energy products and services to businesses, homes, community aggregations and public sector customers across the continental United States, 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 further accelerating the nation’s transition to a carbon-free future by helping our customers reach their sustainability goals, setting our own ambitious goal of achieving 100% carbon-free generation by 2040, and by investing in promising emerging technologies to eliminate carbon emissions across all sectors of the economy. Follow Constellation on LinkedIn and Twitter.

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