U.S. Bets on Small Nuclear Reactors to Help Fix a Huge Climate Problem

Towering over the Savannah River in Georgia, the first nuclear reactors built from scratch in the United States in more than 30 years illustrate the enormous promise of nuclear power — and its most glaring weakness.

The two new reactors at the Vogtle nuclear power plant will join two older units to create enough electricity to power two million homes, 24 hours a day, without emitting any of the carbon dioxide that is dangerously heating the planet.

But those colossal reactors cost $35 billion, more than double the original estimates, and arrived seven years behind schedule. That’s why no one else is planning to build large reactors in the United States.

Instead, the great hope for the future of nuclear power is to go small.

Nearly a dozen companies are developing reactors that are a fraction of the size of those at Vogtle, betting that they will be quicker and cheaper to build. As the United States looks to transition away from fossil fuels that have underpinned its economy for 150 years, nuclear power is getting renewed interest, billions of dollars from the Biden administration and support from Republicans.

One reason is that nuclear plants can run at all hours, in any season. To those looking to replace coal and gas with wind and solar energy, nuclear power can provide a vital backstop when the air is calm or the sky is cloudy.

“The United States is now committed to trying to accelerate the deployment of nuclear energy,” John Kerry, President Biden’s climate envoy, said in September. “It’s what we believe we absolutely need in order to win this battle.”

But the push to expand nuclear power, which today supplies 18 percent of electricity, faces enormous hurdles.

In a major setback last week, the first serious effort to build small reactors in the United States was abruptly canceled amid soaring costs. While other projects are still moving forward, the industry has consistently struggled to build plants on time and on budget. The Nuclear Regulatory Commission, which oversees the safety of the nation’s nuclear fleet, is less experienced with novel reactor technologies. And the problem remains of how to dispose of radioactive waste.

The clock is ticking. Governments, companies and utilities want to slash their carbon emissions to near-zero within a few decades.

“This is the best period of support I’ve ever seen for nuclear power in my 20-year career,” said Jacopo Buongiorno, a professor of nuclear engineering at the Massachusetts Institute of Technology. “But the industry has to deliver. If they can’t, there’s a real risk that this moment of opportunity could slip away.”

A country warms to nuclear

American opinion about nuclear power has shifted since 1979, when a partial reactor meltdown at Three Mile Island horrified a nation and rock stars like Bruce Springsteen headlined “No Nukes” concerts at Madison Square Garden.

One recent Pew survey found that 57 percent of Americans favor more nuclear plants, up from 43 percent in 2016. Republicans have traditionally backed atomic energy, but the survey found rising support among Democrats.

While many environmental groups still oppose nuclear power, some skeptics are softening.

As a young lawyer with the Natural Resources Defense Council, Dan Reicher sued the federal government over nuclear waste at power plants and weapons sites, which he called “one of the most dangerous industrial operations in our nation.” But today, he says, the threat of global warming has made him “more comfortable” with nuclear power.

California Gov. Gavin Newsom, a Democrat, pushed to keep open Diablo Canyon, a nuclear plant he once sought to close. Five states have reversed decades-old bans on building reactors. Texas and Virginia are exploring investments in new plants.

“We need everything we can put our hands on in terms of low-carbon resources,” said Mr. Reicher, a former assistant secretary of energy during the Clinton administration. “We have to put the longer-term risk of nuclear waste against the imminent impacts of climate change.”

The struggle to build plants

Anyone looking to build a reactor today has to keep costs under control, a problem that doomed past projects.

When most existing reactors were built in the 1960s and ’70s, regulators frequently ratcheted up safety rules, creating expensive delays. Some projects were poorly managed, or faced legal challenges. By the 1980s, utilities had stopped ordering new reactors, scared off by ballooning costs.

“The economics just didn’t work,” said Arnie Gundersen, chief engineer at Fairewinds Associates and a critic of nuclear power.

The reactors at Vogtle were supposed to be different. In 2008, utilities in Georgia and South Carolina sought approval to build two large reactors apiece, using a novel design with advanced safety features.

Nothing went as planned.

Construction began before designs were finalized and major changes had to be made partway through. Components arrived late. Workers installed 1,200 tons of rebar in a way that differed slightly from the design, triggering a seven-and-a-half month regulatory delay. In 2017, South Carolina’s utilities abandoned their project after spending $9 billion with nothing to show except higher consumer bills. One utility went bankrupt and two executives pleaded guilty to fraud.

Only Georgia pushed ahead. Southern Company, the project’s largest owner, says the reactors will displace coal, which makes up one-fifth of its electricity mix.

“It hasn’t always been easy,” said John Williams, vice president of business operations for the reactors. “But it’s going to be a great asset for the people of Georgia for a very long time.”

Still, the typical Georgia Power customer has already been charged more than $900 for the reactors and could soon pay an additional $9 per month in higher electricity bills. “It’s going to harm ratepayers,” said Patty Durand, a former candidate for the Georgia Public Service Commission.

No other utility wants to risk following in Georgia’s footsteps.

“The real tragedy with Vogtle is that we stopped after two units,” said Julie Kozeracki, a nuclear expert and senior adviser at the Energy Department. “Three of the biggest issues were starting with an incomplete design and construction plan, an untrained work force and an immature supply chain. We solved all three and then stopped.”

Enter small reactors

To control costs, developers of next-generation reactors want to create smaller, standardized designs that require a lower upfront investment and can be easily duplicated.

“These nuclear megaprojects had just gotten way too complex,” said Jay Wileman, president of GE-Hitachi Nuclear Energy, which is designing a slimmed-down version of its boiling-water reactor that is only 300 megawatts — one-quarter the size of the 1,117-megawatt units at Vogtle.

Ontario Power Generation plans to deploy four of them in Canada, hoping to bring down costs as it builds the same design again and again. The Tennessee Valley Authority is considering at least one.

Other companies are exploring radically new reactor designs that, in theory, can’t melt down and don’t require big containment domes or other expensive equipment. Some might be manufactured in factories and assembled on-site, potentially lowering costs.

Today, every American nuclear plant uses light water reactors, in which water is pumped into a reactor core and heated by atomic fission, producing steam to create electricity.

But visit Argonne National Laboratory, outside Chicago, which helped create the civilian nuclear power industry, and you’ll find a drawing of a genealogical tree with three dozen apples, each representing a different reactor design developed by the lab since World War II.

Among them is a reactor that was cooled by sodium instead of water and operated for 30 years in Idaho. Sodium allows the reactor to operate at lower pressures, potentially reducing the need for the thick shielding used by light-water reactors.

Two companies are developing variations on Argonne’s design. TerraPower, backed by Bill Gates, plans to build a sodium-cooled reactor to replace a retiring coal plant in Wyoming. Oklo, based in California, wants to build tiny 15-megawatt reactors that might power remote communities in Alaska or electric-truck charging stations.

Other ideas are popping up. X-Energy, a start-up in Maryland, is developing a pebble-bed reactor cooled by gas that produces not just electricity but also heat — something wind and solar plants can’t do. Dow wants to install four at a chemical plant in Texas to replace natural-gas turbines that create steam for industrial processes.

Argonne’s expertise in alternative nuclear technologies is suddenly in high demand.

“A lot of these reactor start-ups are seizing the opportunity of this foregone innovation over the last six decades,” said Roger Blomquist, a principal nuclear engineer at Argonne. “This is the wave of the future.”

Hurdles ahead

For nearly five decades, the Nuclear Regulatory Commission has regulated large light-water reactors. Now it has to consider a dizzying array of new technologies and their safety characteristics.

The approval process can be slow. To date, the N.R.C. has certified only one small reactor design, developed by NuScale Power. NuScale’s light-water technology is similar to existing plants, but the company argued that smaller reactors required different safety rules, such as smaller evacuation zones in case of accidents. Securing approval took a decade and cost $500 million.

“It’s a pretty big barrier to entry,” said Jose Reyes, NuScale’s chief executive. “And this was for a technology that regulators are already familiar with.”

At a recent House hearing, Republicans and Democrats alike complained that a draft rule meant to help license advanced reactors was 1,173 pages long and largely unworkable.

“Everyone agrees that reactors need to be safe,” said Adam Stein, director of nuclear innovation at the Breakthrough Institute, a pronuclear research organization. “But it’s also possible for a regulator to be too conservative and too risk-averse.”

Some sympathize with the N.R.C. “The agency has limited resources, and suddenly they’re asked to build up technical capacity to look at all these different technologies in a short amount of time,” said Ahmed Abdulla, an engineering professor at Carleton University.

The N.R.C. says it is improving and recently greenlit a novel test reactor by Kairos, a start-up, in just 18 months.

“If you look at how we were doing reviews 10 years ago, we’re a different agency today,” said Robert Taylor, deputy director for new reactors.

The ultimate test, however, will be whether any new reactors get built. Here, there are warning signs.

Last week, NuScale announced it was canceling plans to deploy six 77-megawatt reactors in Idaho by 2030, which would have been the nation’s first small nuclear plant.

The problem was that it couldn’t sign up enough customers. Soaring costs didn’t help: In January, NuScale said the price of building the reactors had jumped from $5.3 billion to $9.3 billion, citing higher interest rates and materials costs. On a per-megawatt basis, the project had become as expensive as Vogtle.

“The small reactors being hyped by the nuclear industry and its allies are simply too late, too expensive, too uncertain and too risky,” said David Schlissel, an analyst for the Institute for Energy Economics and Financial Analysis, who has urged utilities to pursue alternatives like solar and geothermal power.

Others say NuScale faced unique risks in going first, from navigating regulators to finding new business models.

“You see this a lot with emerging technologies,” said Joshua Freed, who leads the climate and energy program at Third Way, a center-left think tank. “Most of the early electric vehicle start-ups didn’t succeed, apart from Tesla. But electric cars are very much here today.”

Other challenges loom. The United States isn’t yet producing enough of the specialized fuel for advanced reactors. There’s no long-term plan for nuclear waste. Siting new plants can be contentious: Last year, officials in Pueblo County, Colo., withdrew plans to replace a retiring coal plant with a reactor after local backlash.

But at a time when wind and solar are facing their own challenges, supporters say nuclear power is too important to abandon.

“The demand for clean energy is almost unprecedented,” said Maria Korsnick, president of the Nuclear Energy Institute, an industry group. “There’s no real solution that does not involve nuclear.”