Constellation Energy orders $100m transformer for Three Mile Island reactor revival

Constellation Energy has placed a $100 million order for a main power transformer, marking a critical step in the revival of the Three Mile Island nuclear reactor in Pennsylvania, according to Reuters. The transformer is the largest single piece of equipment needed for the reactor’s restart. Constellation has committed to investing $1.6 billion by 2028 to bring the plant back online.

Following a detailed survey of the site, which assessed essential infrastructure and equipment, Constellation decided to move forward with the restart. In September 2024, the company secured a 20-year power contract with Microsoft to support the initiative. The revived reactor, located on an island in the Susquehanna River, will supply 835 MW of power, aiding in offsetting Microsoft’s data centre electricity usage. Unit 1, the focus of Constellation’s reactivation efforts, had ceased operations in 2019 due to economic challenges.

Constellation aims to have Unit 1 operational by 2028, though this timeline depends on meeting physical and regulatory requirements, including compliance with US and local regulations. The company is also investing in refurbishing critical components such as the turbine, generator, and cooling systems to ensure the plant’s operational readiness.

In July 2024, Constellation held discussions with Pennsylvania’s governor’s office and state legislators to secure funding for the reactor’s potential restart. These actions demonstrate Constellation’s commitment to reactivating the facility, which originally operated from 1974 until its closure in 2019.