A unit of Pennsylvania's Three Mile Island nuclear plant will be restarted as part of a new energy-sharing agreement with Microsoft, which plans to use it to power the data centers it operates as part of its push into artificial intelligence.

As tech companies scramble to secure new sources of energy, Microsoft on Friday announced a 20-year deal to restart a nuclear reactor at Pennsylvania’s Three Mile Island — a facility made infamous by a partial meltdown in 1979.

Environmental and health campaign groups led by Clean Wisconsin have signed an open letter criticizing the decision by Microsoft to use methane gas from We Energies at the site in Racine County. The cloud giant has permission to develop up to 1,000 acres of land in Mount Pleasant, Racine County, into a data center campus.

Microsoft isn't the only tech company looking to nuclear power to fuel its AI ambitions. Earlier this year, Amazon.com Inc.'s cloud computing division agreed to spend $650 million to acquire a data center campus connected to Talen Energy Corp.’s 40-year-old nuclear power plant on the Susquehanna River in Pennsylvania.

The owner of the shuttered Three Mile Island nuclear power plant says it plans to restart the reactor under a 20-year agreement that calls for tech giant Microsoft to buy the power to supply its data

Microsoft is in the midst of a deal that would bring the infamous Three Mile Island nuclear power plant back to life, according to reporting by The Washington Post. If the name sounds familiar, it’s because the Pennsylvania plant was home to a partial meltdown of one of its reactors back in 1979.