Three Mile Island is Back, Thanks to Microsoft AI

Three Mile Island, the sight of the worst nuclear disaster in U.S. history, will reopen to power Microsoft’s AI data center needs as part of a new 20-year contract. Constellation, it’s owner, shut down the facility in 2019 because it was economically unviable as a business.

“The energy industry cannot be the reason China or Russia beats us in AI,” Constellation CEO Joseph Dominguez said. “This plant never should have been allowed to shut down. It will produce as much clean energy as all of the renewable [energy producers] built in Pennsylvania over the last 30 years.”

As Constellation puts it, Three Mile Island “operated at industry-leading levels of safety and reliability for decades before being shut down” five years ago. The issue, the company says, isn’t the Level 5 nuclear meltdown that occurred in 1979 at its Unit 2 reactor, but rather that the Unit 1 reactor it’s now reopening for Microsoft suffered from unfair perception issues when nuclear power is, in fact, safe and clean.

Microsoft agrees with that assessment, of course.

“This agreement is a major milestone in Microsoft’s efforts to help decarbonize the grid in support of our commitment to become carbon negative,” a Microsoft statement notes.

No shuttered U.S. nuclear power plant has ever reopened, and there are regulatory hurdles to clear. But Constellation says it’s been in talks with Microsoft since 2023 and its inspection of the facility revealed it to be in extraordinarily good shape. The firm will invest $1.6 billion restarting Three Mile Island, and it will help offset those costs with federal subsidies and other tax breaks tied to the 2022 Inflation Recovery Act. The reopening could lead to between 600 and 3,400 new jobs in the area and generate $3 billion in state and federal taxes.

If Three Mile Island does return, it will generate 835 megawatts of power, enough to power over 700,000 homes. It will also be renamed to Crane Clean Energy Center, an obvious move given the facility’s history. And it may not be alone: Decommissioned nuclear power plants in Michigan and Iowa could also see new life in this AI era, assuming they can be restarted safely.