The United States is preparing for a significant shift in nuclear energy production, aiming to deploy small, advanced reactors by 2026 as part of a broader effort to revitalize the sector. This move comes after decades of stagnation, where regulatory hurdles, public skepticism, and cheaper alternatives led to plant closures and limited investment in new nuclear technologies. However, surging electricity demand – particularly from data centers – is driving a renewed interest in nuclear power as a reliable, high-output energy source.
The Department of Energy’s Reactor Pilot Program
The Department of Energy (DOE) is spearheading this revival through its Reactor Pilot Program, which seeks to quadruple nuclear energy output by 2050. The program has fast-tracked the testing of innovative reactor designs, with a key milestone set for mid-2026: achieving criticality – a self-sustaining nuclear fission reaction – in at least three advanced reactor concepts.
This ambitious timeline is deliberate. According to nuclear engineer Leslie Dewan, the pilot’s purpose is to identify which designs are viable under real-world constraints. The selected companies are working on a range of technologies, including molten salt reactors, high-temperature gas reactors, fast reactors, and sodium-cooled systems.
Leading the Charge: Valar Atomics and Natura Resources
Among the frontrunners is Valar Atomics, based in California, which is developing a high-temperature gas reactor (HTGR) called the Ward 250. HTGRs utilize tiny uranium particles coated in carbon and ceramic layers, creating a built-in safety mechanism that prevents radioactive leakage even at extreme temperatures. Fuel particles are loaded into graphite blocks, and helium gas flows through them, heating up to generate steam and electricity. Valar has already broken ground on the Ward 250 and achieved cold criticality in a government test facility, validating its core physics.
Texas-based Natura Resources is pursuing molten salt reactors, another inherently safe design. In this approach, uranium is mixed into molten salt, which heats up with fission and transfers heat through a pump-driven heat exchanger. An emergency freeze plug ensures a safe shutdown if the salt overheats, draining the fuel into a containment tank. Natura has secured a construction permit for a 1-megawatt research reactor and recently acquired Shepherd Power to bolster its supply chain and regulatory expertise.
Challenges and Next Steps
Despite progress, significant hurdles remain. Meeting the 2026 criticality deadline requires unprecedented acceleration. Beyond that, proving long-term reliability is critical. Companies must demonstrate controlled operation at design temperatures, material stability, and consistent performance to gain trust from regulators and future customers.
“I view this 2026 date as the start of the interesting data-gathering period, by no means the finish line,” says Leslie Dewan, underscoring that this milestone is just the beginning of rigorous testing and validation.
The revival of US nuclear power isn’t just about new reactors; it’s a strategic response to growing energy demands and a recognition of nuclear energy’s potential as a stable, high-capacity power source. The next few years will be pivotal in determining whether these advanced designs can deliver on their promise and reshape the future of electricity generation.
