How to reopen a closed nuclear plant

The problem: The U.S. aims to reach net-zero emissions by 2050. But to do that, it’ll need cleaner sources of energy. In 2023, about 60 percent of U.S. electricity generation came from fossil fuels, according to the Energy Information Administration.

The fix: Two companies, Constellation Energy and Holtec International, are currently working on restarting shuttered plants that could be test cases for the somewhat retro future of nuclear power in the U.S.

Constellation recently announced plans to restart one of two nuclear reactors at Three Mile Island, the Pennsylvania nuclear plant that it shut down in 2019. Three Mile Island partly melted down in 1979, in the worst nuclear reactor accident in U.S. history.

And in Michigan, Holtec is working on restarting the Palisades nuclear plant, which shut down in 2022.

The Biden administration is working “in a very concrete way” to restart nuclear plants, Ali Zaidi, the White House climate adviser, told Reuters this week. The White House did not respond to a request for comment about what this might entail.

How it might work: Restarting a nuclear plant takes more than just flipping a switch. First, there’s hiring. Holtec’s work force fell from 600 to 220 when it shut down, but Nick Culp, Holtec’s senior manager of government affairs and communications, said the company intended to be fully staffed by spring. Holtec requalified more than two dozen workers to operate the Palisades plant who will also need to be licensed by the Nuclear Regulatory Commission, he said.

Then, there’s inspection work. Holtec said in August that the plant’s primary coolant system had been cleaned. The company is working on inspecting the plant’s main turbine and transformers, among other parts, and on moving some of its spent fuel to an on-site storage facility, it said. Holtec aims to have the plant up and running again by the fourth quarter of 2025.

Constellation spent more than a year and a half inspecting the reactor it’s working to restart at Three Mile Island, which will be renamed the Crane Clean Energy Center. The company said it planned to spend $1.6 billion to get the reactor operating again and hoped it would reopen in 2028.

Last month, the Biden administration approved a $1.52 billion loan guarantee to help Holtec reopen the plant. Constellation is also reportedly seeking a federal loan guarantee.

The obstacles: Restarting mothballed nuclear reactors takes a lot of time, investment and regulatory approvals. And it would reverse a trend: More than a dozen reactors shut down in the U.S. between 2012 and 2022.

“A lot of people are watching to see how this goes for us,” said Culp, the Holtec senior manager. “When we restart, I think it’s going to change the conversation a bit.”

Public opinion on nuclear energy has also been changing. More than half of Americans in 2023 said they were either strongly or somewhat in favor of nuclear energy — the highest level of public support for the industry in a decade, according to Gallup.

What’s next: The Energy Department said, the country will need 200 gigawatts of added nuclear capacity by midcentury to meet increasing electricity demand while reaching net-zero emissions.

But, as Brad Plumer reported, only one other dormant nuclear plant in the U.S. could plausibly be restarted: the Duane Arnold plant in Iowa. Other reactors that have recently shut down are already being dismantled. — Allison Prang