Constellation Energy is gearing up to restart the infamous Three Mile Island nuclear plant in Pennsylvania, which witnessed the worst nuclear disaster in U.S. history. This move aims to support Microsoft’s soaring energy needs for its artificial intelligence operations.
On Friday, the Baltimore-based company announced plans to revive the Unit 1 reactor, which has been offline for five years. This reopening represents a bold step in the energy sector to address the skyrocketing power demand from AI-focused data centers built by tech giants like Microsoft, Meta, and Google.
The deal spells good news for Microsoft. Constellation plans to sell the electricity generated by the plant to the tech giant under a 20-year agreement, pending regulatory approval. This partnership helps Microsoft strive for its goal of powering data centers with carbon-free energy.
The plant is set to resume operations in 2028 and will operate until at least 2054, rebranded as the Crane Clean Energy Center in honor of the company’s former CEO, Chris Crane.
Constellation Energy estimates that the reopening will create over 3,000 jobs and contribute more than 800 megawatts of carbon-free electricity to the grid. The economic impact on Pennsylvania could be significant, with projections showing a $16 billion boost to the state’s GDP and more than $3 billion in state and federal tax revenues.
According to Bobby Hollis, vice president of energy at Microsoft, “this agreement is a big leap in our journey to decarbonize the grid.” Our goal is to improve grid dependability by developing carbon-free sources in close collaboration with energy providers.
Located near Middletown, Pennsylvania, the Three Mile Island plant has been shuttered since 2019. Its Unit 2 reactor suffered a partial meltdown in March 1979, an incident that remains the worst nuclear accident in the nation’s history. According to the U.S. Nuclear Regulatory Commission, the event “had no detectable health effects” on workers or nearby residents.
“The symbolism is huge,” Constellation Energy CEO Joseph Dominguez told the New York Times. “This site is a symbol of the biggest failure in the industry, but it’s starting to come back to life.”
While no U.S. nuclear plant has resumed service after being decommissioned, Three Mile Island could change that narrative if the plan gets the green light. The Palisades plant in Michigan is also on track to restart by the end of 2025.
If all goes well, Three Mile Island will provide Microsoft with about 835 megawatts of energy—enough to power roughly 800,000 homes.
This move marks a significant step toward meeting the growing electricity demands of AI data centers. Earlier this year, the Electric Power Research Institute projected that these facilities could account for over 9% of electricity consumption by 2030—more than double current usage. To alleviate pressure on the grid, tech companies are advocating for co-locating data centers near nuclear plants.
Amazon has also recently made waves by entering an agreement to acquire the aging Susquehanna nuclear plant in Pennsylvania. Yet, this deal has faced criticism from utility companies, warning it could limit power availability, negatively impacting consumers.
Opposition to reopening Three Mile Island has surfaced, with protesters gathering outside the site in August. Nonetheless, recent polls indicate that about 57% of Pennsylvania voters support bringing the plant back online, provided it doesn’t lead to new taxes or increased electricity rates.
