American nuclear plant Palisades reaches another milestone ahead of restart

The Palisades nuclear plant, shut down four years ago, has reached a major milestone ahead of its return to service. After extensive repairs and inspections, technicians brought the unit to operating temperature and pressure for the first time. Palisades' original operating licence is valid until 2031, but the operator believes it can be extended by another 20 years. The United States is betting heavily on restarts, power uprates and upgrades to its existing facilities — over the next three years, the Department of Energy plans to add 5 GW of nuclear capacity this way.

U.S. company Holtec International announced that it had reached another milestone in restoring the Palisades nuclear plant, which had been shut down. Technicians completed the passivation of the primary circuit, during which the unit reached operating temperature and pressure for the first time since it was shut down in 2022. The passivation process creates a protective layer on the surface of the circuit's metal components, preventing corrosion. Nuclear units typically undergo this process during hot functional testing before entering service.

“Completing primary circuit passivation reflects the care and technical rigour our team is bringing to preparing the plant for safe and reliable operation for decades to come,” said Kelly Trice, president of Holtec International.

As part of preparations to restart the 805 MW nuclear unit, technicians repaired the steam generators and primary circuit welds and carried out a comprehensive cleaning of the systems. Holtec says the unit has already undergone more than 300 inspections, and the main turbine generator has been put back in place. The unit is expected to restart later this year.

5 GW of additional capacity from existing facilities

The restarts of the U.S. Palisades and Crane Clean Energy Center plants (formerly Three Mile Island) will return 1.6 GW of nuclear capacity to the country's energy mix. However, under the UPRISE programme (Utility Power Reactor Incremental Scaling Effort), the U.S. Department of Energy is targeting 2.5 GW by 2027 and a further 2.5 GW by 2029.

“Ensuring long-term safety and reliability remains central to our restart mission, and we continue this work with the care and precision it deserves,” Trice added.

Holtec also plans to use the Palisades site to build small modular reactors. Preparatory work is under way on a pair of reactors with a total capacity of 680 MW as part of the Pioneer project. Holtec plans to bring the new units online in the early 2030s, making them among the first modular reactors in the United States.