Once a home of the Manhattan Project, the fields surrounded by forested valleys and rolling hills in Oak Ridge, Tennessee, US, could soon yield another nuclear first.
Concrete foundations and pilings are rising here for what is expected to be one of the first of a new generation of nuclear power plants, known as small modular reactors. The company behind it — Kairos Power — has been developing its technology for almost a decade and is now deep in the throes of construction.
Many companies are racing to build reactors that experts say could, over time, be cheaper than the kind of large nuclear power plants that have been in use for decades. To hear corporate executives and US government officials tell it, the world is at the dawn of a new nuclear age that will provide cheap energy and satiate artificial intelligence technology’s staggering appetite for electricity.
At the centre of this promise is the idea of shrinking the vessels where nuclear reactions heat water to produce steam used to spin turbines. The components of these smaller reactors, the thinking goes, can be mass-produced and assembled more easily than conventional designs built by a small army of highly skilled workers.
Almost all nuclear power plants in operation in the US started generating power decades ago, most of them before Bill Clinton became President. In recent decades, steep costs and long delays, coupled with concerns about safety, have stymied nuclear energy.
“I think a lot of people recognise the value of what nuclear can bring but are still a little bit nervous about whether it can actually be done,” said Mike Laufer, co-founder and CEO of Kairos Power, which is based in the San Francisco Bay Area in the US. “Credibility can be very hard to earn, but it can be lost very quickly.”
America has more nuclear power reactors than any country, but it badly trails in building new ones. In the past decade, China has built more than three dozen reactors while the US completed just two.
President Donald Trump wants new reactors to be a signature achievement of his term. The US Energy Department has awarded $800 million for new reactor technologies.
Nine years ago, the three founders of Kairos Power began developing their designs, pinning their hopes on a new approach. The three men all studied nuclear and mechanical engineering at the University of California, Berkeley, US, where J. Robert Oppenheimer, the leader of the Manhattan Project, once taught.
Kairos executives said they had opted to test each phase of the plant’s development as it progressed, rather than take the approach more common in this line of work — design, construct and hope for the best.
Unlike conventional nuclear plants, Kairos’ reactor will not have large, domed buildings made of concrete and metal. And steam will not billow from huge water towers. Instead of water, the Kairos reactor will heat salt.
The reactor will rise a bit over about 9.8 metres. The full commercial design includes two reactor buildings and a turbine with an overall footprint of 24 hectares.
The company, which has 540 full-time employees, designs and produces its own components. It makes many of the parts in Albuquerque, New Mexico, about 96 kilometres from Los Alamos, the ultimate headquarters of the Manhattan Project.
At its site in Oak Ridge, Kairos is working on a test reactor expected to be complete in 2028; a demonstration unit, capable of producing electricity, is planned for 2030. The company has a contract to supply 500 megawatts of energy capacity — about half the capacity of the typical large-scale nuclear plant — to Google by 2035.
Google’s involvement could make a huge difference. Technology companies investing in AI bring the kinds of money and interest that were missing in the early 2000s when delays and soaring costs last scuppered ambitions for a nuclear renaissance.
The nuclear reactors being built by Kairos and others will run on something called TRI-structural ISOtropic particle fuel, or TRISO, that was developed by the US Department of Energy. The TRISO particles are actually enriched uranium kernels coated with multiple layers of carbon and ceramic.
Thousands of the poppy-seed-size particles are embedded in a graphite matrix to form pebbles the size of golf balls. The TRISO shell confines radioactive material from the uranium as it breaks down and produces heat. With the fuel’s built-in containment system and the molten salt coolant, the reactors won’t need the same costly reinforced containment buildings used in conventional plants, proponents say.
But some scientists are not confident that this new fuel allays all safety concerns. Edwin Lyman, a physicist and the director of nuclear power safety at the Union of Concerned Scientists, said the TRISO particles can generate very high heat, which warrants the use of containment buildings.
“In my view, the claims that are being made about TRISO are way oversold,” Lyman said. “We’re really headed toward a very dangerous experiment on the American people.”
NYTNS