Nuclear unit at Three Mile Island to be restarted to supply Microsoft with electricity

US energy supplier Constellation announced on Friday that it was restarting the Three Mile Island plant in Pennsylvania, the scene of the worst nuclear accident in US history, in order to supply Microsoft with electricity.

According to a press release, the agreement signed with the American computer giant covers 20 years and will allow the restart of unit 1, which was not affected by the 1979 accident.

Before its premature shutdown for economic reasons in 2019, the plant had a production capacity of 837 megawatts, enough to power more than 800,000 homes, the press release recalls.

Powering the industries critical to our nation’s global economic and technological competitiveness, including data centers, requires an abundance of reliable, carbon-free energy every hour of the day, and nuclear power plants are the only energy sources that can consistently deliver on that promise.

Constellation specifies that significant investments will be made to restore the reactor, in particular the turbine, the generator and the cooling systems.

Restarting a nuclear reactor requires prior approval from the U.S. Nuclear Regulatory Commission, after a comprehensive safety and environmental review.

The site, which is expected to create 3,400 direct and indirect jobs, should be operational in 2028.

This agreement represents a major step in Microsoft’s efforts to help decarbonize the gridsaid Bobby Hollis, head of energy for the American giant, quoted in the press release.

In June 2023, Constellation had already signed an agreement with Microsoft to bring nuclear power to one of its data centers in Boydton, Virginia.

The development of artificial intelligence requires enormous computing capacities, provided by legions of computer servers housed in data centers.

The power consumption of these servers is colossal and threatens to saturate the American electrical grid if its capacities are not extended by the addition of new resources.

On Wednesday, Microsoft also announced that it was partnering with asset manager BlackRock to invest $100 billion in infrastructure dedicated to the development of artificial intelligence.

These funds will be used to create or expand data centers and to build electricity production infrastructure to power them.

Having fallen out of favor after the disaster at the Japanese Fukushima plant in 2011, nuclear power, a low-CO2 emitting energy source like wind and solar, is experiencing a resurgence of interest worldwide, driven by climate and energy security imperatives.

According to the International Energy Agency, the world’s nuclear capacity will need to more than double by 2050.

In 2023, only five new reactors representing a total capacity of 5 GW have been commissioned worldwide, while five units have been shut down, according to a report on the state of the nuclear industry released Thursday.

Last year, another nuclear plant reopening project was announced, this time by the American company Holtec, which plans to restart its closed Palisades plant in 2022.