Bill Gates’ TeraPower receives approval to build new nuclear reactor

The Nuclear Regulatory Commission (NRC) this week granted TerraPower a permit to build a new nuclear reactor in the shadow of an aging coal-fired power plant in Wyoming.

TerraPower’s permit is the first issued by the NRC in nearly a decade. Founded in 2015 by Bill Gates and backed by Nvidia, the startup has been working with GE Vernova Hitachi to design a sodium reactor. The final power plant will generate 345 megawatts, about two-thirds smaller than modern full-size reactors but several times larger than many small modular reactor designs favored by other startups.

Sodium reactors differ from other reactors not only in scale but also in design details. Most nuclear reactors built in the past 50 years have been cooled by water, but sodium is cooled by molten sodium, which TerraPower claims should be safer. This is the first commercial nuclear reactor not cooled by conventional water to be approved by the NRC in more than 40 years.

The reactor operates on excess molten sodium, which is stored in large insulated tanks. This allows atoms to continue splitting when demand is low, allowing the hot sodium to conserve that energy and use it to fill gaps in wind and solar power generation. Nuclear power plants operate optimally at near full capacity, so storing excess energy as heat should help reduce power generation costs.

The NRC’s approval is notable because it gives TerraPower permission to build on private land, following a long-established permitting process. The Department of Energy recently relaxed safety rules, but these rules only apply to land owned by the Department.

TerraPower is one of nearly half a dozen nuclear power startups backed by technology companies or their founders. As demand for electricity from data centers increases, the Trump administration is under pressure to increase power generation capacity through measures such as building new nuclear reactors.

Investors have taken note of these two trends, pouring well over $1 billion into nuclear startups in recent months. TerraPower alone has raised a total of $1.7 billion, including a $650 million round that closed in June, according to PitchBook.

Despite the momentum, nuclear power still faces an uphill battle. To date, nuclear power remains one of the most expensive forms of new power generation capacity. Part of this is due to cost overruns at large power plants, but it also reflects the huge strides solar, wind and batteries have made over the years in lowering costs.

Nuclear startups hope to leverage mass production to curb capital spending, but the theory remains unproven. And while manufacturing can help reduce costs, savings often take at least a decade to materialize.