Three Mile Island, Site of Worst Nuclear Accident in U.S. History, Plans to Reopen Under New Microsoft Deal

Mar. 15, 2025

Three Mile Island.Photo:ANDREW CABALLERO-REYNOLDS/AFP via Getty

ANDREW CABALLERO-REYNOLDS/AFP via Getty

A newly-announced Microsoft deal would reopen a retired reactor on the site of the worst nuclear power plant accident in U.S. history.

Constellation Energyannounced the agreement on Friday, Sept. 20, in a news release that they plan to restart Pennsylvania’s Three Mile Island’s Unit 1 reactor. Under the 20-year deal, Microsoft “will purchase energy from the renewed plant as part of its goal to help match the power its data centers in PJM use with carbon-free energy.”

The Unit 1 reactor is adjacent to the Unit 2 reactor, which partially melted down on March 28, 1979, in an event that theUnited States Nuclear Regulatory Commissiondescribed as “the most serious accident in U.S. commercial nuclear power plant operating history.”

According to the agency, however, the “small radioactive releases had no detectable health effects on plant workers or the public.” The agency also noted that the incident led to changes in nuclear plant operations, as well as regulatory oversight and reactor safety.

A plaque about the Three Mile Island accident from 1979.ANDREW CABALLERO-REYNOLDS/AFP via Getty

According to Constellation, which is based in Baltimore, the Unit 1 reactor shuttered in 2019 for “economic reasons.” Before it was retired, the plant generated a capacity of 837 megawatts — “enough to power more than 800,000 average homes."

The new deal with Microsoft will launch a new plant, Crane Clean Energy Center, according to Constellation Energy.

In a statement announcing the restart, ​​Joe Dominguez, the company’s president and CEO, said: “Before it was prematurely shuttered due to poor economics, this plant was among the safest and most reliable nuclear plants on the grid, and we look forward to bringing it back with a new name and a renewed mission to serve as an economic engine for Pennsylvania.”

The company added that the new plant is expected to go online in 2028. The restart of the nuclear reactor, said Constellation, will require “U.S. Nuclear Regulatory Commission approval following a comprehensive safety and environmental review, as well as permits from relevant state and local agencies.”

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TheNew York Timesreported that tech businesses have been eyeing nuclear power in order to meet the increasing amount of energy required for artificial intelligence (AI). Mark Nelson of Radiant Energy Group, a consultancy firm, told the newspaper: “Only a few short years ago, tech companies scoffed at buying nuclear electricity. The return of Three Mile Island is the return of hard reality.”

In a statement shared with PEOPLE on Sept. 20, Pennsylvania Gov. Josh Shapiro said: “Pennsylvania’s nuclear energy industry plays a critical role in providing safe, reliable, carbon-free electricity that helps reduce emissions and grow Pennsylvania’s economy. Under the careful watch of state and federal authorities, the Crane Clean Energy Center will safely utilize existing infrastructure to sustain and expand nuclear power in the Commonwealth while creating thousands of energy jobs and strengthening Pennsylvania’s legacy as a national energy leader.”

“My Administration will continue to work to cut energy costs and ensure the reliability of our energy grid so that Pennsylvanians can have access to affordable power made right here in Pennsylvania for years to come – and the Crane Clean Energy Center will help us achieve those goals,” Shapiro’s statement concluded.

source: people.com