Constellation's Three Mile Island Nuclear Plant Could Restart in 2027

Researched by Industrial Info Resources (Sugar Land, Texas)--Constellation Energy Corporation (Baltimore, Maryland) said Wednesday its former Three Mile Island nuclear power plant in Pennsylvania, which will reopen as the Crane Clean Energy Center, could restart in 2027, about a year ahead of schedule. However, the Nuclear Regulatory Commission (NRC) has yet to officially approve the effort.

The company is looking to restart the plant's 835-megawatt (MW) Unit 1--which was retired in 2019 primarily due to economic reasons--and now is one step closer to making that happen. Unit 2 was closed in 1979 after a partial meltdown and is now owned by a decommissioning company.

"The plant could restart as early as 2027, with the approval of an early interconnection request by grid operator PJM and significant progress made on hiring, reactor operator training and major equipment purchases," Constellation said in a press release.

The company noted the facility is now 64% staffed, and technical milestones reached include the successful inspection of the plant's diesel generator, steam generator, main generator, turbines and other major systems.

Subscribers to Industrial Info's Global Market Intelligence (GMI) Power Project and Plant databases can learn more by viewing the project report and related plant profile.

Constellation executives celebrated the latest development at the Crane Clean Energy Center alongside local officials, executives from Microsoft Corporation (Redmond, Washington)--which has a power purchase agreement (PPA) in place to offtake output from the new unit--and Pennsylvania Governor Josh Shapiro (D).

For more information on Microsoft's agreement and another Constellation PPA (with Meta Platforms Incorporated (Menlo Park, California)) for the output from another nuclear plant, see June 4, 2025, article - Meta to Buy Nuclear Power from Illinois Constellation Plant.

Constellation in February said it had filed a request to connect the Crane project to the grid. Regarding the NRC approval process, the company said on Wednesday it "remains on track with its regulatory filings and recently submitted key licensing amendments." In May, the NRC approved a license request to rename Unit 1 to the Crane Clean Energy Center.

But Governor Shapiro was the first one to implore the PJM to approve the project's interconnection, in a 2024 letter to the grid operator. "Projects sited at locations of a dormant interconnection, where a generating facility shut down in the past, present an excellent opportunity to meet our shared goals of supplying reliable power to the grid and encouraging economic growth ... Given the lengthy review process for new projects, it is imperative that shovel-ready resources like the crane Clean Energy Center be allowed to come online as quickly as possible rather than waiting in the queue."

The Pennsylvania governor is not the only one looking to strengthen the electricity grid, as the Trump administration, Congress and grid managers are exploring ways to do so--in part by reforming the process for approving new transmission projects as well as those in the interconnection queue. For more information, see May 12, 2025, article - Fixing the Grid: Diverse Federal Activities May Point to Progress.

Industrial Info Resources (IIR) is the leading provider of industrial market intelligence. Since 1983, IIR has provided comprehensive research, news and analysis on the industrial process, manufacturing and energy related industries. IIR's Global Market Intelligence (GMI) helps companies identify and pursue trends across multiple markets with access to real, qualified and validated plant and project opportunities. Across the world, IIR is tracking over 200,000 current and future projects worth $17.8 Trillion (USD).