Nuclear plant could be back online in 2027 to supply power to Microsoft
US power utility Constellation Energy has secured a $1bn (€862m) loan from the US Department of Energy (DOE) to support the restart of Unit 1 at the Three Mile Island nuclear station – now renamed the Crane Clean Energy Center – in Pennsylvania.
The plant is set to supply Microsoft with power via a long-term power purchase agreement (PPA) and could now generate electricity into the 2050s.
The DOE said the announcement marks the first project to receive a concurrent conditional commitment and financial close under the Trump administration, which is pushing to add more nuclear power to the grid.
The 819-MW pressurised water reactor unit was shut down in 2019 over economic concerns and after failing to secure the subsidies needed to compete with cheaper alternatives. It was first connected to the grid in 1974.
Constellation said earlier this year it would accelerate the restart and the reactor is now expected to return to service in 2027, about a year ahead of schedule.
The loan is expected to cover most of the estimated project startup costs, which are set at around $1.6bn. The first advance is due in Q1 of 2026. The loan would be provided through the DOE’s Loan Programs Office and comes with a guarantee from Constellation that it will protect taxpayer money.
According to Greg Beard, senior advisor to the Loan Programs Office, Constellation could have completed the project without federal funding. However, the loan will reduce electricity prices for consumers across the PJM Interconnection grid.
PJM Interconnection is the largest regional transmission organisation in North America, managing the power grid for 13 states and Washington DC.
“What’s important for the administration is to show support for affordable, reliable, secure energy in the US,” Beard said. “This loan to Constellation will lower the cost of capital and make power cheaper for those PJM ratepayers.”
Constellation runs the largest nuclear fleet in the US, with a fleet of 21 nuclear power plants at 15 sites. The 15 sites are Braidwood, Byron, Calvert Cliffs, Clinton, Crane (formerly Three Mile Island), Dresden, FitzPatrick, LaSalle, Limerick, Nine Mile Point, Peach Bottom, Quad Cities, Ginna, Salem and South Texas.
Unit 2 at the Three Mile Island site is the reactor that suffered a partial nuclear meltdown in March 1979, due to a combination of equipment malfunctions and human error. It is being decommissioned and will not be returning to service.
Constellation said Unit 1 is a “a fully independent facility” and its long-term operation was never impacted by the Unit 2 accident.
The Energy To Win The AI Race
Energy secretary Chris Wright said: “Constellation’s restart of a nuclear power plant in Pennsylvania will provide affordable, reliable, and secure energy to Americans across the Mid-Atlantic region. It will also help ensure America has the energy it needs to grow its domestic manufacturing base and win the AI race.”
He said financing for the project is needed to help address surging electricity prices and add more around-the-clock power to the grid.
Over recent years, big tech companies have increasingly signed PPAs with nuclear plants in a bid to guarantee their supply of reliable power.
In June Constellation signed it second major PPA with a big tech company, confirming a 20-year deal with Meta to supply it with 1,100 MW of power from its Clinton, Illinois, nuclear power plant. The contract, which will begin in June 2027, will see Meta offtake the entire output of the Constellation-owned single-unit facility.
Also in June, Amazon Web Services signed a 17-year PPA with Talen Energy for 1.92 GW of energy from the two-unit Susquehanna nuclear power plant in Pennsylvania.
