Bill Gates wants to build advanced nuclear at an old Wyoming coal plant. It’s a long shot

The Bill Gates–funded nuclear science think tank TerraPower and Warren Buffett’s PacifiCorp announced plans on June 2 to build an operable 345-megawatt sodium-cooled fast nuclear reactor demonstration project at a retiring coal plant in Wyoming.

Gates said that TerraPower will use the coal plant’s infrastructure and workforce to construct and operate a Natrium reactor, a design developed in collaboration with GE Hitachi Nuclear Energy.

Chris Levesque, CEO of TerraPower, said that its Natrium design is ​“on track to provide clean energy later this decade.”

Depending on your perspective, that view is either hugely ambitious or highly delusional.

Gates bullish on nuclear power

The week after making that announcement, Gates spoke at a Nuclear Energy Institute event, saying, ​“We need more nuclear power to zero out emissions in America and to prevent a climate disaster.”

“While America’s current nuclear capacity serves the country well, there are far more reactors slated for retirement than there are new reactors under construction,” Gates said. He called for keeping ​“safe reactors operating” as well as building new ones.

TerraPower was spun out of Intellectual Ventures, the think tank created by ex-Microsoft CTO Nathan Myhrvold, to develop nuclear reactors that run primarily on depleted uranium. Initial investors included Gates, Charles River Ventures and Khosla Ventures.

TerraPower’s original design, the traveling-wave reactor, apparently has been abandoned in favor of the sodium-cooled fast breeder reactor.

The new reactor works in tandem with a long-duration energy storage system using molten nitrate salt that is ​“an order of magnitude larger than the biggest lithium-ion battery storage system currently in existence,” according to Gates. (For now, that titleholder appears to be the 300-megawatt/1,200-megawatt-hour Moss Landing Energy Storage Facility in Monterey County, California.)

Plenty of hurdles

The Natrium fast reactor uses high-temperature liquid sodium as its reactor coolant instead of water and employs high-assay low-enriched uranium (HALEU) as its nuclear fuel. HALEU is enriched 5 percent to 20 percent in the isotope uranium-235. By comparison, the world’s fleet of light-water reactors uses fuel enriched to less than 5 percent uranium-235.

Here’s one big hurdle for TerraPower: There is no current supply of HALEU, according to Power Magazine. It reports that establishing a commercial supply would require more demand and ​“a minimum of seven years to develop fuel cycle infrastructure.”

Safety is another issue. The sodium coolant is under high levels of pressure and is explosive in the event of a breach, which requires the use of more expensive components and construction.

The ability for a fast reactor to reuse spent nuclear fuel in a closed fuel cycle does open a potential path to dispose of the more than 77,000 metric tons of spent fuel now temporarily stored in pools and casks at sites in 35 states.

Still, fast breeder reactors like the Natrium design engender undue national security risks, two nuclear proliferation opponents argue in a recent essay in The National Interest. This is especially true if TerraPower wants to export its technology around the world, they contend.

Market and regulatory headwinds

The Biden administration is supportive of nuclear power, and the DOE is backing TerraPower specifically.

The DOE’s Advanced Reactor Demonstration Program was launched last year and awarded $80 million each to TerraPower’s Natrium design and X-energy’s Xe-100 design for a high-temperature, gas-cooled small modular reactor. The department intends to invest a total of $3.2 billion in this program over seven years, with industry partners providing matching funds.

To meet its 2030 decarbonization goals, the Biden administration is counting on existing nuclear plants to be part of the energy mix. With more than 90 nuclear reactors operating at 55 power plants across the U.S., nuclear energy currently generates about 20 percent of America’s electricity each year.

But nuclear reactors are closing down due to economics, risk and competition from cheap natural gas, wind and solar power. New York’s Indian Point nuclear plant was permanently closed last month. Canary reported on what the imminent shutdown of the Diablo Canyon nuclear plant means for the California grid. And Exelon plans to close two reactors in Illinois with a total capacity of about 4 gigawatts this year.

Meanwhile, new nuclear power is stalled out in the U.S. No new plant with an application submitted since the formation of the Nuclear Regulatory Commission in 1975 has yet begun operation. The only nuclear power plant under construction in the U.S. is facing ongoing delays and wild budget overruns: The price tag of Georgia’s two Vogtle reactors now tops $27 billion — more than twice the 2008 estimates.

Worldwide, just 2.4 gigawatts’ worth of new nuclear plants were installed in 2020 (in Russia, China and South Korea), compared to about 100 gigawatts of solar and 60 gigawatts of wind. Nuclear power remains the most expensive form of generation except for gas peaking plants, according to the World Nuclear Industry Status Report.

TerraPower is betting that its Natrium design can buck those trends with lower costs and faster construction times, but the odds are long.

Even NuScale’s design, a small modular reactor that bears some resemblance to existing light-water reactors, poses challenges to the testing and approval processes of the Nuclear Regulatory Commission.

Introducing a completely new reactor design like the Natrium model, which operates on radically different principles than a light-water reactor, is a deep technological challenge that will face profound market and regulatory headwinds.

The billionaire class is enamored with fission, fusion and space travel, but they have yet to make any of them economically viable.

(Image credit: Nicolas Hippert)