X-energy wins permit for four reactors at Texas Dow plant

Each Xe-100 reactor is designed to generate 80 megawatts of electricity and 200 megawatts of heat. X-energy says the reactors will not be operational until the early 2030s. No small modular reactor is currently operating in the United States.

The industry has backed small modular reactors, or SMRs, on the premise that smaller units can be built faster and at lower cost. Those advantages have not yet been proven. X-energy says its design, which circulates helium gas over uranium-containing fuel pellets, is safer than many existing reactors. The Union of Concerned Scientists has challenged both that claim and the pace of the permit review.

“The NRC only accomplished this feat by pushing consideration of critical safety questions to a later date—issues the NRC should’ve fully resolved before green lighting construction,” Edwin Lyman, the organization’s director of nuclear power safety, said in a statement.

Interest from hyperscalers and data center developers seeking electricity has helped the nuclear sector. Amazon’s Climate Pledge Fund led X-energy’s $500 million Series C-1, and Amazon has committed to buying 5 gigawatts of capacity from the startup. X-energy raised $1 billion in an initial public offering in April, but investor optimism has since cooled. Nuclear plants are expensive and can take years to build; the company’s first reactors are likely to be costly. The permit approval lifted X-energy shares, recovering last week’s losses, but they remain below half their initial offering price.