Valar Atomics is first US firm to power an advanced reactor
Valar Atomics has become the first U.S. startup to produce power from an advanced reactor, with its Ward 250 unit in Utah now generating electricity after reaching criticality on June 18, 2026. The breakthrough matters because it connects small modular nuclear to Nvidia's plan for a nearly waterless 30-megawatt AI data center. The California-founded company staged a live demonstration on July 1, 2026, powering an Nvidia RTX Spark desktop PC directly from reactor output.
Key Takeaways
- Valar Atomics' Ward 250 reactor in Emery County, Utah, is the first startup-built advanced reactor in the U.S. to produce nuclear power.
- On July 1, Valar Atomics and Nvidia announced a collaboration to explore a 30MW, closed-loop AI factory that uses almost no local water.
- The live demo powered an Nvidia RTX Spark PC from the reactor, marking what the firms describe as the first time advanced nuclear energy ran an AI chip.
- Commercial operation still requires Nuclear Regulatory Commission licensing, though the NRC aims to shorten review times.
- Ward 250 is the second reactor to go critical under the Department of Energy's pilot program tied to a July 4, 2026 federal deadline.
What Did Valar Atomics Achieve in Utah?
Founded in 2023, Valar Atomics broke ground in Orangeville, Utah, last September and brought its Ward 250 reactor to criticality on June 18, 2026, at the Utah San Rafael Energy Lab in Emery County. According to Deseret News, the unit is now generating 100 kilowatts of electricity, making Valar Atomics the first startup in history to produce nuclear power.
The achievement came under the U.S. Department of Energy's Reactor Pilot Program and President Trump's executive order calling for at least three advanced reactors to reach criticality by July 4, 2026. Ward 250 was the second to hit that mark, after Antares Nuclear's Mark-0 reactor at Idaho National Laboratory earlier in June. It was also the first DOE-authorized reactor built and operated outside a national laboratory.
Why Is Valar Atomics Partnering With Nvidia?
On July 1, Valar Atomics announced a collaboration with Nvidia to explore AI data centers in Utah powered directly by advanced nuclear energy. If the project moves forward, the companies say it would be the first time advanced nuclear directly powers artificial intelligence workloads.
The firms are studying a 30-megawatt facility that would pair Valar's helium-cooled Ward 250 design with Nvidia's DSX data center architecture, which uses a highly water-efficient direct liquid cooling system. Tom's Hardware reported that the proposed site would be roughly 300 times smaller than the approved Stratos data center in Box Elder County, Utah.
At a live event, Valar Atomics activated its microreactor on stage and used reactor-generated electricity to power an Nvidia RTX Spark desktop PC built on Blackwell architecture. The demonstration offered a proof of concept for nuclear-backed AI compute at a time when data centers face rising power and water demands.
What Happens Next for Valar Atomics?
Before Valar Atomics can sell electricity commercially, the Nuclear Regulatory Commission must license the Ward 250 reactor. NRC Chairman Ho Nieh told the Deseret News editorial board that the commission hopes to cut federal licensing review times to less than 18 months.
Valar CEO Isaiah Taylor, who launched the company at age 24, has framed Ward 250 as a reactor built to make power—not just demonstrate criticality. As this story breaks, readers tracking celebrity breaking news will hear more about whether Utah becomes the template for water-light, nuclear-powered AI factories across the United States.