Three beginnings to provide fireworks for the Department of Energy’s Fourth of July celebration of meeting a major nuclear milestone. They opened the new reactors as part of a test program aimed at starting what Energy Secretary Chris Wright called “America’s nuclear renaissance” to develop and use the next generation of atomic energy.
Some companies in the test program have indicated they may reach criticality—the term used to describe a nuclear reactor that sustains a chain reaction, a critical step in providing power—as soon as July 4, following a deadline set by President Donald Trump for the executive order last year. But experts say that while the pilot is good PR for the industry, there is still a long way to go before the new reactor designs become commercial realities.
“These examples mean everything and nothing,” said Adam Stein, director of the Nuclear Energy Innovation program at the Breakthrough Institute. “They do a lot for companies that reach critical mass, but even for those companies, they’re not commercial products. They’re experimental machines.”
For decades, America’s nuclear power plant has been dominated by large, light-water reactors, which use water to transfer heat and support nuclear reactions. The dream of building small reactors with different, more innovative designs has long been out of reach, thanks in part to the slow regulatory environment and large upfront costs required for small companies to develop new reactor designs.
“For a long time this industry was considered stagnant—a nuclear power plant was 10 years away,” Stein said. The pilot program “shows that’s not true, if you’re being intentional. It changes the narrative, and it changes the perception. That means a lot to the investment community.”
A growing number of investors and tech figures in Silicon Valley see small nuclear reactors, which could provide 24/7 carbon-free energy to power data centers and other operations, as part of a new golden age of technology. The tech world is leaning heavily on the Trump administration to ease regulations and speed up the development of small nuclear projects. The administration responded with a series of actions, including creating a screening program by executive order last year. In classic Trumpian fashion, the executive order, issued in May 2025, set an ambitious timeline for acquiring at least three critical reactors, coinciding with the nation’s 250-year celebrations on July 4.
In February, the Department of Energy quietly overturned many environmental and safety regulations for reactors operating under that department, including those being built as part of the pilot program. (Similar regulatory cuts are now being made to the Nuclear Regulatory Commission, which approves reactors to be sold commercially.) Stein says processes to shorten requirements such as environmental impact statements, which can take years, have created “huge time savings” for companies in the program.
Reactor designs in the pilot program do not only benefit from cutting red tape. Many companies also have assistance from federally funded national laboratories. Valar Atomics reached critical mass late last year at the Los Alamos National Laboratory using a core that carries launch fuel and key structural components provided by the lab. (The company also reached critical mass with a second reactor at a state-funded lab in Utah earlier this month.) Antares Nuclear and Deployable Energy—other startups in test programs that met the executive order’s July 4 deadline—also reached national lab importance.
Matt Loszak, founder and CEO of Aalo Atomics, thanks the government for prioritizing the development of the new reactor at the speed his company has been able to move. His company is part of a pilot program and has not yet reached a critical stage, although it expects to do so soon.
