Three Nuclear Startups Achieve Criticality in Pilot Program: Implications and Challenges

Three nuclear startups have reached a significant milestone by achieving criticality in a pilot program aimed at advancing America’s nuclear energy capabilities. This achievement comes just before the Fourth of July celebrations, as noted by Energy Secretary Chris Wright, who describes it as a part of “America’s nuclear renaissance.” The startups, including Valar Atomics, Antares Nuclear, and Deployable Energy, met the criticality deadline set by President Donald Trump last year.

Significance of Reaching Criticality

Reaching criticality is a pivotal step in nuclear energy development, representing the moment a reactor sustains a chain reaction. Adam Stein, director of the Nuclear Energy Innovation program at the Breakthrough Institute, highlighted that while these prototypes are significant, they are still not commercial products. “These prototypes mean everything and nothing,” he stated, emphasizing the gap between achieving criticality and actual market deployment.

The pilot program is seen as a catalyst for change in the nuclear industry, which has been historically slow due to regulatory challenges and high development costs. Stein remarked, “The industry has long been viewed as stuck—a nuclear reactor was always 10 years away.” This pilot initiative aims to alter that perception, fostering a more favorable investment climate.

Regulatory Changes and Industry Response

The Trump administration has implemented several regulatory changes to expedite the development of smaller nuclear reactor designs. These changes include slashing environmental and safety regulations, which have historically delayed progress. For instance, the Department of Energy has streamlined processes for environmental impact statements, allowing startups to move forward more quickly.

Matt Loszak, cofounder and CEO of Aalo Atomics, noted the positive impact of government prioritization on their progress. “Now, it’s like, done the next day, because it’s a priority for the nation,” he explained, reflecting the accelerated pace of approvals compared to previous years.

Challenges Ahead for Nuclear Startups

Despite these advancements, significant hurdles remain for these startups. Reaching criticality does not equate to generating electricity. For example, Aalo’s reactor still requires additional components to function as a commercial product. Moreover, the path to commercialization involves navigating the Nuclear Regulatory Commission’s licensing process, which can take years.

Moreover, supply chain issues, particularly regarding fuel sourcing, pose additional challenges. Brett Rampal, senior director of nuclear and power strategy at Veriten, cautioned against over-optimism, stating, “some in the industry may be over-romanticizing the idea of a new golden age for nuclear energy without fully acknowledging the financial realities.”

• Valar Atomics reached criticality at Los Alamos National Laboratory.
• Antares Nuclear and Deployable Energy also achieved criticality at national labs.
• The pilot program was initiated via an executive order in May 2025.
• Regulatory changes aim to shorten the licensing process for new reactors.