Three Mile Island Restart Faces Grid Delays to 2031

Constellation Energy's plans to restart a nuclear reactor at the former Three Mile Island site in Pennsylvania have encountered significant delays from regional grid operators, potentially pushing full operations to 2031 despite the company's target of 2027.

The utility, the largest operator of nuclear plants in the United States, aims to revive Unit 1 at the facility, which shut down in 2019 after more than four decades of service. Under a long-term agreement, the reactor would supply about 835 megawatts of clean power to data centers operated by Microsoft. Constellation has renamed the site the Crane Clean Energy Center and secured a $1 billion federal loan to support the $1.6 billion project. However, PJM Interconnection, the grid operator serving 13 states including Pennsylvania, has indicated that necessary transmission upgrades could delay full grid connectivity until 2031.

Company executives maintain that the restart remains on track for the second half of 2027. "We still expect to meet our 2027 target," Chief Executive Officer Joseph Dominguez said, noting ongoing negotiations with PJM and local utilities to accelerate the process. Constellation described the 2031...