US Regulator Approves Construction Permit for X-Energy's First Industrial-Scale Small Modular Reactors

Nuclear startup X-energy announced that the U.S. Nuclear Regulatory Commission (NRC) has granted a construction permit for its first four commercial Xe-100 small modular reactors (SMRs). The reactors will be built at a Dow chemical plant in Texas, with each unit capable of generating 80 megawatts of electricity and 200 megawatts of heat. X-energy stated that this approval represents the first time an advanced nuclear reactor has been permitted for construction at an industrial site in the United States.

Small modular reactors are seen as a key solution to the surging energy demands of AI data centers. Proponents argue that shrinking the reactor size will speed up construction and reduce costs, though these advantages remain unproven. No SMR is currently operational in the U.S., and X-energy expects the Dow reactors to become operational in the early 2030s.

The approval has drawn criticism from safety advocates. Edwin Lyman, director of nuclear power safety at the Union of Concerned Scientists, argued that the NRC achieved this rapid approval by pushing critical safety questions to a later date, rather than resolving them before greenlighting construction.

Despite these concerns, hyperscalers have shown strong interest in nuclear power. Amazon’s Climate Pledge Fund led X-energy’s $500 million Series C-1 round, and the tech giant has committed to buying 5 gigawatts of capacity from the nuclear startup. X-energy went public in April 2026, raising $1 billion, but investor optimism has tempered due to the high costs and long timelines associated with nuclear projects. The company's shares are currently trading at less than half their initial offering price. The recent permit approval provided a slight boost to the stock, recovering some of last week's losses.