How to bring a dead nuclear power plant back to life

The US nuclear industry has been struggling to hold its ground for decades as it contends with rising costs, an aging fleet, a shrinking workforce, and stiff competition from natural gas and renewable power. 

The most recent US nuclear reactors to come online, units 3 and 4 at Plant Vogtle in Georgia, started up in 2023. It was years behind schedule and billions of dollars over budget. Meanwhile, more than a dozen reactors have shut down since 2013. Several companies developing advanced reactors and small modular reactors, promising greater safety and lower costs, have seen their projects and their businesses collapse.

But in the past year, some big tech companies have taken steps toward a revival. 

Amazon has signed a $500 million deal with X-energy to deploy 5 gigawatts worth of small modular reactors (SMRs) in Washington state. The company is also investigating new nuclear projects in Virginia. Google and nuclear startup Kairos Power agreed to develop molten salt-cooled nuclear reactors, an approach that promises greater efficiency and lower costs. Microsoft has made advanced nuclear energy, including technologies like SMRs and fusion, a part of its energy strategy. These tech firms are looking to meet their climate goals while sating energy appetites that have exploded with the push for artificial intelligence. Last year, new data center power demand grew 26 percent to more than 5 gigawatts in North America.   

The case to lean into nuclear power at this moment is compelling. It could generate massive quantities of electricity, day or night, rain or shine, without emitting greenhouse gasses into the atmosphere. Nuclear fission is also one of the safest energy sources. Coal kills more than 32 people per terawatt-hour of electricity produced while nuclear kills about 0.03. But building a new nuclear power plant from scratch, especially a new design, is an arduous, expensive process that can span decades. 

At the same time, old, carbon dioxide- and soot-spewing coal power plants are also shutting down. Many states are looking to fill the void while also trying to meet their goals to decarbonize their power grids.

That’s why tech companies are also looking to revive shuttered nuclear plants. Progress is underway to resurrect reactors at three nuclear power plants that were slated for dismantling and could restart as soon as next year. It’s a stunning and unprecedented development for the nuclear industry. 

“If you told me we would’ve been talking about this 10 years ago, I would’ve laughed at you,” said Patrick O’Brien, head of government affairs and communications at Holtec International, a nuclear services company that until recently specialized in shutting nuclear plants down. 

Three plants are on the resuscitation list. The 800-megawatt reactor at the Palisades Nuclear Power Plant in Michigan, which shut down in 2022, is slated to revive by the end of 2025; Holtec bought the Palisades plant in 2022 and is now leading its restart. Microsoft signed a deal with Constellation to resuscitate the 835-megawatt Unit 1 reactor at Three Mile Island in Pennsylvania, which initially turned off in 2019 and could power up by 2028. NextEra Energy is mulling breathing life back into the 600-megawatt Duane Arnold nuclear power plant in Iowa. The plant closed in 2020 after sustaining damage during a derecho, a fast, powerful thunderstorm. 

Restarting these plants is a critical test for nuclear power in the US, and how they fare will bolster or erode confidence in broader ambitions for a new generation of nuclear deployment.

But whether they will help keep global warming in check depends on how much they will displace dirtier energy sources as opposed to merely enabling new demand. 

How to restart a nuclear reactor

Alas, restarting a nuclear power plant doesn’t involve flipping a comically large circuit breaker. The reality is much more tedious. 

For a would-be nuclear resurrectionist, the main tasks are appeasing the regulators and reinvigorating the hardware. 

The Nuclear Regulatory Commission (NRC), the federal agency in charge of commercial nuclear reactors, says the reason these power plants — Palisades, Three Mile Island, Duane Arnold — are eligible to be restarted is that, from the regulator’s perspective, they’re only mostly dead. 

When a reactor first gains approval from the NRC, its initial operating license runs for 40 years. At the end of the first license, the operator can then seek a 20-year extension. “The key to all of these restart efforts is the fact that the licenses that are involved have not yet hit their expiration date,” said Scott Burnell, a spokesman for the NRC. 

These reactors were shut down ahead of schedule not for technical problems but because the business wasn’t panning out. 

After shutting down a plant, operators remove fuel from the reactors and place it in spent fuel pools. They disassemble pipes and machinery. They drain coolants and lubricants to prevent contamination. A complete decommissioning can cost up to $2 billion and take 20 years. 

But the three plants under restart consideration haven’t gotten far along in the disassembly process. Until recently, no one has sought to bring back a plant already slated for retirement, so there isn’t an established rulebook for how to go about it. “There’s never been a case up to this point where a company has come back and said, ‘Well, I’ve changed my mind,’” Burnell said. The first thing someone seeking to resuscitate a nuclear reactor must do is seek an exemption from the current rules that make shutting down a one-way street, which requires an enormous amount of paperwork. 

The operator then has to put a safety plan in place and bring the plant back up to the original requirements under its operating license. Therein lies the next undertaking. 

Palisades, Three Mile Island, and Duane Arnold shut down relatively recently, but they’ve still been offline for years. Imagine letting a car sit in your driveway unused for a couple of years and then trying to fire it up. Odds are, it won’t start on the first try. The motor may have seized, the fuel may have separated, the battery may have discharged completely. Even sitting unused, components like rubber hoses, gaskets, and tires can oxidize and turn brittle with time. Metal parts can rust. A shuttered nuclear power plant faces similar concerns, albeit with significantly higher consequences. 

Nuclear operators have to first meticulously investigate all the parts of their offline facilities before they get the thumbs-up to power up again. 

However, this shutdown, inspection, and resuscitation process can also be an opportunity. Holtec’s O’Brien noted that operating nuclear power plants have regularly scheduled downtime lasting a month or so to conduct maintenance and refuel. But a longer outage gives the operator more time to do more extensive upgrades and restoration. 

“We have parts of the turbine that have been sent out to North Carolina for refurbishment that’ll be gone for a year with the work being done,” O’Brien said. “You couldn’t have done that when you’re an [actively] operating plant.”

The other challenge is the workforce. Running a nuclear power plant requires highly specialized personnel, and since the US has been so slow in building reactors, many veteran staffers have retired or left the industry while fewer new graduates are rising to replace them. Palisades employed 600 workers when operating and brought in 1,000 more during refueling and maintenance periods.

When a plant is slated for shutdown, many of those workers leave the area or retire. So to restart a nuclear facility, operators need to get their teams back together, sometimes bringing workers out of retirement while recruiting and training new ones.  

Nuclear revivals still have to prove their economics

The biggest challenge for nuclear restarts may not be the hardware or the regulations, but competition. According to a 2021 report from the Congressional Research Service, “The US nuclear power industry in recent years has been facing economic and financial challenges, particularly plants located in competitive power markets where natural gas and renewable power generators influence wholesale electricity prices.”

The reactor revivers say they can overcome what killed these power plants in the first place. With Palisades, Holtec is securing a power purchasing agreement with Wolverine Power Cooperative, a nonprofit that provides electricity to 280,000 homes and businesses in rural Michigan. Rather than competing head-to-head with other generators, this guarantees the plant can sell a given amount of electricity at a fixed rate. 

O’Brien said Holtec is putting up $500 million of its own money. The company also received $300 million in grants from the state of Michigan and a $1.52 billion loan guarantee from the US Department of Energy for its effort.  

Holtec is also aiming to use the Palisades site to deploy two 300-megawatt small modular reactors, essentially becoming its own first customer for these reactors and demonstrating them for future clients. Since the site is already certified to be a nuclear power plant, it cuts out a lot of the development costs that come with building a plant on fresh soil. Holtec is aiming to have its first SMR up by 2030. 

While a lot of the recent activity around nuclear power has been fueled by the energy-hungry tech industry, Michigan has set its own ambitious climate goals that make Palisades an even more attractive option. The state is aiming to phase out all of its coal-fired power plants by 2030. Coal currently provides more than 22 percent of the state’s electricity. That’s a big hole to fill in over the next six years. 

Like many states, Michigan is experiencing growing electricity demand, particularly as hotter summers increase cooling needs. The rise of electric cars and switching from natural gas heating to electric heat pumps is increasing energy appetites as well. The state also sees an opportunity to get a piece of the AI action and is instituting tax breaks for new data centers.

Revived plants like Palisades can’t keep running forever though. In a car, regular oil changes, tire replacements, and inspections can keep it on the road for a long time. But if the engine block starts to wear down, it’s usually not worth the time or money to replace it. Similarly, with a nuclear power plant, ongoing fueling and maintenance can keep it operational, but if its equivalent of an engine block — the reactor pressure vessel around the reactor core — becomes brittle over time as neutrons from nuclear fission bombard it, that can be expensive and difficult to replace. Its integrity is often the main determinant of the overall lifespan of a nuclear plant. 

Palisades was already 50 years old when it went offline, and the NRC’s current regulations are set up to allow for two 20-year renewals after an initial 40-year license for a nuclear power plant. “We’ve had several plants that have come in for a second renewal, which would allow them to run essentially for 80 years,” Burnell said. A plant could theoretically push that further, but no one has tried yet. 

And all nuclear plants have to deal with rising costs. Maintaining a nuclear workforce is getting more expensive, and safety regulations continue to ratchet up. Inflation is making materials more pricey and higher interest rates are increasing financing expenses. At the same time, photovoltaic solar panels and wind turbines have experienced extraordinary price drops and explosive growth around the world.

The nuclear industry’s challenges remain immense, but concerns about climate change might end up being the most compelling driver for new nuclear power. When it comes to ample, around-the-clock, zero-emissions power, nuclear is a strong contender in the competition. 

But nuclear energy is now facing another curveball. Donald Trump’s reelection to the White House likely means that addressing climate change will become a lower priority, as it did during his first term. How much the federal government will continue backing nuclear restarts and new companies is unclear, and the industry might need to figure out a new pitch for more public investment.