Three Mile Island nuclear power plant reopens and sells electricity to Microsoft

A decommissioned nuclear power plant in Pennsylvania could soon be restarted to meet some of Microsoft's growing energy needs.

On Friday, Constellation Energy and Microsoft announced the signing of a 20-year power purchase agreement that will bring one of the reactors at the Three Mile Island nuclear power plant back online to exclusively meet the energy needs of the tech giant's massive data centers that support artificial intelligence.

Neither Constellation Energy nor Microsoft disclosed financial terms of the deal.

The restart of reactor unit 1 in Three Mile Island, which was shut down in 2019, requires approval from the US Nuclear Regulatory Commission. If this is granted, the power plant is expected to start operating again in 2028.

A first for nuclear energy

“Powering industries critical to our nation's global economic and technological competitiveness, such as data centers, requires an abundance of energy that is carbon-free and reliable 24/7. Nuclear power plants are the only energy sources that can consistently deliver on that promise,” Joe Dominguez, president and CEO of Constellation Energy, said in a statement Friday.