X-energy wins NRC permit for four commercial Texas reactors

By Olivia Hart

The Nuclear Regulatory Commission approved X-energy’s application to build four Xe-100 reactors at a Dow chemical plant in Texas, the nuclear startup said Monday. X-energy says each reactor can generate 80 megawatts of electricity and 200 megawatts of heat.

X-energy called the decision the first approval for an advanced nuclear reactor at a U.S. industrial site. The company also set a long timeline: Dow’s reactors will not operate until the early 2030s.

What did the NRC approve?

The construction permit covers X-energy’s first four commercial reactors at the Dow site. It authorizes construction, but it does not make the reactors operational or prove their economics. As of Monday’s decision, no small modular reactor was operating in the United States.

X-energy’s investment case rests on making a smaller reactor faster and cheaper to build. Proponents of small modular reactors, or SMRs, say size reductions can shorten construction and lower costs, though those advantages have yet to be proven. The permit advances construction, but leaves commercial performance several years away.

What remains disputed about reactor safety?

X-energy’s design sends helium gas over uranium-containing fuel pellets. The company claims the design is “safer than many existing reactors.” The Union of Concerned Scientists disputes that comparison and the speed with which X-energy received the permit.

Edwin Lyman, the group’s director of nuclear power safety, issued the Union’s statement. He said: “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.”

Lyman did not identify a specific technical defect in the Xe-100 design in the statement. His objection concerned the NRC’s sequence, arguing that construction should not precede full resolution of the critical safety questions. The permit therefore advances construction without settling the Union’s broader objection.

Why does Big Tech matter?

X-energy has benefited from strong interest from hyperscalers and data center developers seeking additional electricity. Amazon’s Climate Pledge Fund led the company’s $500 million Series C-1, while Amazon committed to buy 5 gigawatts of capacity from the startup.

The 5-gigawatt commitment equals 5,000 megawatts. That is more than 15 times the 320 megawatts of electrical capacity designed for the four Dow reactors, whose combined thermal capacity is 800 megawatts.

Amazon’s commitment therefore exceeds the Dow project’s electrical capacity by a wide margin. The announcement did not allocate the order to these four units or say they alone would fulfill it.

Nuclear power plants are expensive to build and can take years to complete. X-energy hopes eventually to reduce both construction time and cost, but its first reactors are likely to be pricey. Amazon supplies capital and a demand signal, but neither proves the first build will be cheap or fast.

What are investors paying for?

X-energy’s April initial public offering raised $1 billion amid strong investor enthusiasm for nuclear power. Since then, investors have tempered their optimism, and the shares trade at less than half their initial offering price.

The permit approval produced only a small jolt yesterday, enough to recover the previous week’s losses. That price action suggests the regulatory milestone did not settle doubts about execution, cost or the long wait until operations begin.

X-energy still must demonstrate that construction can proceed on schedule, that the first reactors can operate within its broad early-2030s window, and that costs can fall after a likely expensive debut. Until then, the permit advances the project but leaves the business case untested. The market’s more-than-50% discount to the IPO price captures the gap between regulatory progress and commercial proof.