Constellation Energy

Operates America's largest fleet of carbon-free nuclear plants and leads industry modernization efforts. - Nation's largest electricity producer pursuing digital modernization across expanded fleet following Calpine acquisition

The NRC approved something unprecedented in January 2026: replacing the analog safety controls at an operating nuclear reactor with fully digital systems. Constellation's $167 million upgrade at Limerick transforms control rooms built in the 1980s into modern digital command centers—the first time regulators have greenlit swapping multiple analog safety systems for a single digital platform while fuel rods are still running. The industry has been trying to make this leap for 30 years, blocked by regulatory caution and the stakes of getting it wrong. Just days after securing this approval, Constellation completed its acquisition of Calpine Corporation on January 7, 2026, creating the nation's largest electricity producer with over 55,000 megawatts of generating capacity across nuclear, natural gas, and geothermal assets.

Updated Feb 5

The nation's largest producer of carbon-free electricity, now also the largest overall power generator with nearly 60 GW of nuclear, gas, and renewable capacity. - Largest U.S. power generator following Calpine acquisition

West Virginia has no base-load natural gas power plants online. That's about to change. Governor Patrick Morrisey announced that Calpine, a Constellation Energy subsidiary, will build a $1 billion, 500-megawatt gas plant in Marshall County—part of $4.2 billion in energy investments the state has attracted in just four weeks. The goal: transform a coal-dependent economy into what Morrisey calls 'the battery of the East Coast.'

Updated Jan 24