X-energy gets green light to build its first small modular nuclear reactors

The US Nuclear Regulatory Commission has approved a construction permit for X-energy’s first four commercial small modular reactors, planned for a Dow chemical plant in Texas. It is the first approval for an advanced nuclear reactor at a US industrial site, but the project also highlights the gap between the promise of smaller reactors and their still unproven cost and construction advantages.

Each Xe-100 reactor is designed to produce 80 megawatts of electricity and 200 megawatts of heat. X-energy expects the plant to operate in the early 2030s; its helium-cooled design uses uranium-containing fuel pellets, though safety questions remain under scrutiny. Amazon has led a $500 million investment round and agreed to buy 5 gigawatts of capacity from the company, whose shares are now trading below half their initial public offering price.