Holtec International Announces Completion of Primary System Passivation

COVERT TOWNSHIP, MI — Holtec International has announced a significant milestone in its effort to restart the Palisades Nuclear Power Plant in Southwest Michigan. The company completed passivation of the plant's primary system, bringing the reactor back to operating temperature and pressure for the first time since the facility shut down in May 2022.

What Passivation Means

According to the International Atomic Energy Agency, passivation is the process of making metal tubes and fittings less reactive and more resistant to corrosion from the nuclear plant's fuel. At Palisades, crews brought the main reactor system up to its normal operating temperature and pressure, then used an electrolyte mix to restore the metal's protective properties.

Visible steam rose from the plant during the testing phase — marking the first time in nearly four years that the system has operated under those conditions. Holtec officials say this milestone demonstrates the technical rigor and diligence they are bringing to position the plant for safe, reliable operation.

Major Progress on the Road to Restart

The passivation work builds on nearly two years of repairs, inspections, and upgrades at the Covert Township site. Among the major projects already completed include:

  • Repairs to thousands of steam generator tubes
  • Restoration of critical welds within the reactor system
  • A comprehensive cleaning of the primary system — the first of its kind at the plant — which reduced radiation exposure levels in key work areas
  • More than 300 inspections of piping and welds
  • Reinstallation of the main turbine generator

Holtec President Kelly Trice stated, "The completion of primary system passivation reflects the diligence and technical rigor our team is bringing to position the plant for safe, reliable operation for decades. Ensuring long-term safety and reliability remains the central focus of our restart mission, and we continue to execute this work with the care and precision it warrants."

Next Steps

With this phase now complete, the system will be cooled again as crews move into the next round of testing and final preparations. That includes additional equipment upgrades, continued inspections, and eventual preparations for loading nuclear fuel — one of the final steps before restart.

A Historic Restart

Holtec is working toward restarting Palisades in 2026. If successful, it would mark the first time in U.S. history that a nuclear power plant has been brought back into operation after being shut down for decommissioning.

Originally opened in 1971, Palisades operated for more than 50 years before its closure under previous owner Entergy. Today, the plant is expected to produce more than 800 megawatts of carbon-free electricity once it returns to service — enough to power hundreds of thousands of homes while supporting grid reliability across Michigan.

Small Modular Reactors Planned for Site Expansion

At the same time, Holtec is continuing to push forward with plans to expand the site beyond the existing reactor. The company is pursuing construction of two small modular reactors, or SMRs, at Palisades — a newer generation of nuclear technology designed to be smaller, more flexible, and faster to build.

Holtec says the two planned units — known as Pioneer 1 and Pioneer 2 — would generate a combined 680 megawatts of electricity, complementing the output of the existing plant. The project received a major boost in late 2025, when it was selected for a $400 million matching grant from the U.S. Department of Energy.

The company is also moving through the federal permitting process with the U.S. Nuclear Regulatory Commission, which has already accepted the first portion of its construction application for review. If approved, the new reactors could come online in the early 2030s.

State and Federal Support

The restart of Palisades has received the support of state and federal officials. The facility has secured a $1.52 billion loan from the Department of Energy to help fund the restart process.

For Southwest Michigan, the restart of Palisades — and the potential addition of next-generation reactors — would solidify the lakeshore as a key player in the future of nuclear energy and long-term power generation in the Midwest.

Timeline Remains on Track

Despite the technical challenges and regulatory hurdles, Holtec maintains the restart remains on track. The company has completed inspections of more than 300 pipes and welds, plus the restoration of the main turbine generator.

The next milestone will involve allowing the plant to cool down before more tests and maintenance procedures are carried out. Crews are still preparing to load nuclear fuel into the system, which will be one of the final steps before the plant can begin generating power again.

Economic and Environmental Impact

Once operational, the Palisades Nuclear Plant will provide clean, carbon-free electricity to Michigan without the emissions associated with fossil fuel generation. The plant's output of more than 800 megawatts would support hundreds of thousands of homes while helping Michigan meet its climate goals.

The potential addition of small modular reactors could further enhance Michigan's clean energy portfolio. SMRs represent a promising technology that could provide additional carbon-free power while being smaller, more flexible, and potentially faster to construct than traditional nuclear reactors.

As Holtec continues its work at Palisades, the company remains focused on safety and reliability. The successful restart of this historic facility would mark a significant achievement in nuclear energy and provide Michigan with a reliable source of clean energy for decades to come.