
WASHINGTON—The U.S. Department of Energy celebrates yet another win for the American nuclear energy renaissance. Early Saturday, as part of the U.S. Department of Energy (DOE) Reactor Pilot Program, Aalo Atomics’ test reactor, Aalo-X, successfully completed a zero-power fueled criticality demonstration. The experiment took place at Idaho National Laboratory and is the fourth DOE-authorized advanced reactor to achieve the criticality milestone, exceeding the July 4th goal outlined by President Trump in his May 2025 executive order.
“Last month I toured the Aalo facility at Idaho National Laboratory and was impressed by the company’s determination to successfully demonstrate their technology by the Fourth of July,” said U.S. Energy Secretary Chris Wright. “President Trump asked for three advanced reactors to be authorized and achieve criticality by the 250th anniversary of our great country. I’m pleased to share that through the dedication and hard work of Aalo, INL and DOE, we have surpassed that ask and delivered four!”
Aalo-X joins a growing list of successful advanced reactor designs and spotlights the continued progress and momentum of participants in DOE’s Reactor Pilot Program and the Nuclear Energy Launch Pad initiative. In June, Antares Nuclear’s Mark-0 reactor, Valar Atomics’ Ward 250, and Deployable Energy’s Unity achieved criticality.
“The hardest problem in nuclear was never the physics, our country simply forgot how to build. The success of the Department of Energy Reactor Pilot Program is proof America can execute again,” said Yasir Arafat, President and CTO, Aalo Atomics. “We are proud to play a major role in America’s nuclear renaissance, going from breaking ground to a sustained chain reaction in just eight months, one of the fastest reactor builds in modern American history.”
The fourth criticality of a DOE authorized reactor design surpasses what many skeptics thought American reactor developers could achieve in response to President Trump’s precedent-setting directive. The Reactor Pilot Program leverages DOE authorization to expeditiously certify and construct first-of-a-kind advanced reactor designs for demonstration. The new authorization pathway is a shining example of how regulatory reform can accelerate innovation and help usher in a golden age for the nuclear energy industry and advancement of President Trump’s Energy Dominance agenda.
Learn more about the Reactor Pilot Program.
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