Constellation Energy, the current owner of the Three Mile Island nuclear plant in Pennsylvania, has announced plans to restart one of the site’s reactors following an agreement with Microsoft to supply power to its growing artificial intelligence operations. The reactor, which will be reactivated for the first time in five years, was shut down in 2019 due to economic reasons.
The plant is known for being the site of the worst commercial nuclear accident in U.S. history, which occurred in March 1979 when a valve malfunction resulted in the overheating of the Unit 2 reactor, which is still undergoing decommissioning.
Constellation shut down Unit 1, an adjacent reactor, in 2019, but will now reactivate it based on a 20-year contract to supply electricity to Microsoft’s data centers, whose energy demand is rapidly expanding. According to the company, this reactivation will add 835 megawatts to Pennsylvania’s power grid, create about 3,400 jobs, and inject at least 16 billion dollars into the local economy.
The plant will be renamed the Crane Clean Energy Center, in honor of Chris Crane, former CEO of Constellation’s parent company.
“Before its premature closure due to financial challenges, this plant was one of the safest and most reliable in the power grid. We are excited to reactivate it with a new name and a renewed mission,” said Joe Dominguez, CEO of Constellation Energy.
For the plant to return to operation, a significant investment in infrastructure renewal will be required, including replacing or upgrading critical components such as turbines, generators, transformers, and cooling and control systems. The reopening is still dependent on a thorough safety and environmental review by the U.S. Nuclear Regulatory Commission, expected in 2028. Additionally, Constellation will seek licenses that would allow the plant to operate until at least 2054.
The growing energy demand driven by tech giants like Microsoft, Google, Amazon, Meta, and Apple is putting pressure on the power sector. Goldman Sachs estimates that the energy consumption of these data centers will increase by 160% by 2030, potentially accounting for 8% of the total energy generated in the U.S. However, the rise in demand also raises environmental concerns.
A recent study by the British newspaper The Guardian revealed that carbon emissions from data centers of companies like Google, Microsoft, Meta, and Apple could be up to 662% higher than the officially reported figures.
