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The U.S. Army has selected five companies to develop and deploy nuclear microreactors at military installations across the United States in a program aimed at giving bases a more reliable power source during conflicts and reducing dependence on vulnerable civilian electricity grids and fuel supplies.

The Army and the Defense Innovation Unit announced agreements worth up to $2.2 billion combined for the five companies under the Janus program. The contracts will support the design, construction and initial operation of the reactors, with payments tied to technical milestones.

The Army expects the program to eventually support more than 20 microreactors at military installations, although officials said the five companies are still developing and testing their designs, and not all are expected to have reactors operating by 2028.

The initial sites are Fort Bragg in North Carolina, Fort Campbell in Kentucky, Fort Hood in Texas, Fort Benning in Georgia, and Fort Drum in New York.

Five Companies Selected

The five companies selected by the Army are Antares Nuclear, BWXT Advanced Technologies, General Atomics Electromagnetic Systems, Radiant Industries, and Westinghouse Government Services.

Antares will develop a reactor for Fort Bragg, while BWXT will work on a system for Fort Campbell. General Atomics will bring its Tactical Energy System to Fort Hood, Radiant will develop its system for Fort Benning, and Westinghouse will work on a reactor for Fort Drum.

The Army said the companies will own and operate the reactors rather than transferring ownership to the service. Each company will receive funding according to milestones, meaning future payments can be reduced or stopped if a project fails to meet expectations.

The agreements are expected to run from fiscal 2027 through 2031 and will cover development, construction, and the first year of operations.

The Army did not disclose the individual value of each company’s agreement. However, Radiant has said it could receive up to $750 million under the Janus program to develop and deploy 15 of its Kaleidos microreactors.

Radiant’s reactor is designed to produce 1 megawatt of electricity and is described by the company as transportable and ready to be connected to existing infrastructure. The reactors are undergoing testing at the Idaho National Laboratory’s DOME facility.

General Atomics is developing its Tactical Energy System, known as GA-TES. The system has a baseline output of 5 megawatts and can be scaled to as much as 20 megawatts. It is designed to be transported by truck or rail.

The Army’s main objective is to make military installations less vulnerable to disruptions in the civilian power grid and fuel supply chains.

Jeff Waksman, the Army’s principal deputy assistant secretary for installations, energy and environment, said the military now faces a different energy environment than it did in previous conflicts.

“Unlike in prior conflicts, we now know that our domestic electric grid is potentially at risk in a conflict. We also know that we will not necessarily be able to move fossil fuels easily wherever we need them to go,” Waksman said.

He added that Army infrastructure currently depends heavily on liquid fossil fuels, particularly diesel, for backup power. “That makes nuclear energy just a natural game changer for the Army,” Waksman said.

The concern extends beyond the continental United States. Waksman pointed to U.S. military facilities in the Pacific, where energy supplies can depend on fuel transported by foreign-flagged vessels.

The Army believes nuclear microreactors could provide a more stable source of power for critical infrastructure and reduce the risks associated with long fuel supply chains.

Army officials said the five installations were selected after an assessment that considered their missions, power-grid conditions, environmental issues and safety requirements.

Brandon Cockrell, the Army’s deputy assistant secretary for Energy & Sustainability, said the locations also reflected the military’s need to maintain its ability to deploy forces.

“It’s really difficult to look across the five and not draw the immediate conclusion that this is a direct link to power projection,” Cockrell said.

Reactors Will Not Replace Power Grid

The microreactors are not intended to completely disconnect the bases from commercial electricity. Army officials said the installations will remain connected to the civilian power grid, while the reactors will provide an additional source of electricity for critical infrastructure.

The approach is intended to give military installations greater resilience if the commercial grid is disrupted. The reactors will also not use highly enriched, weapons-grade uranium. The Army said none of the planned systems will rely on that type of fuel.

Several of the designs instead use high-assay low-enriched uranium, or HALEU. Radiant and Antares are developing reactors that use HALEU-based TRISO fuel, while General Atomics’ Tactical Energy System uses uranium zirconium hydride fuel.

The Army also said nuclear waste will not be stored permanently at the military installations. Officials are working with the Energy Department on arrangements for removing radioactive waste.

The reactors will be subject to Army licensing rather than the licensing system used by the Nuclear Regulatory Commission for commercial nuclear facilities. Army officials said safety will remain a requirement before any reactor is placed into operation.

2028 Target

The Janus program was launched after the Trump administration issued executive orders in 2025 calling for faster development and deployment of advanced nuclear technologies for national security.

The Army’s target is to have at least one nuclear microreactor operating at a U.S. military installation by September 30, 2028.

Officials acknowledge that achieving that goal will be difficult. The United States does not currently have an operational commercial nuclear microreactor providing electricity to the power grid, and the five companies are still developing their systems.

Waksman said the Army does not expect all five companies to have operating reactors by 2028. “We don’t expect all five of these companies to turn on a reactor in 2028. In fact, they definitely will not,” he said. “But we do believe we have a very practical pathway to delivering at least one of these reactors on/by September 30, 2028.”

The Army initially identified nine potential locations for the Janus program. Fort Wainwright in Alaska, Holston Army Ammunition Plant in Tennessee, Joint Base Lewis-McChord in Washington and Redstone Arsenal in Alabama were later removed from the final list.

Waksman said the Army paired companies and installations based partly on technical considerations and relationships with nearby utility providers.

The service also wants to demonstrate the technology on U.S. soil before considering possible deployments overseas.

“The intent here is to choose the lowest-hanging fruit; we want to choose sites that we think are going to be the cheapest and fastest to deploy and the easiest,” Waksman said.

He added that deploying the technology at a U.S. installation first would allow the Army to determine whether the systems can work before considering more difficult locations such as remote overseas bases or islands.

Fuel Supply Challenges

The Army’s nuclear ambitions also face a major supply-chain challenge. The United States currently produces only a small share of the world’s enriched uranium, while the Energy Department and National Nuclear Security Administration are working to expand domestic enrichment capacity and production of HALEU.

Waksman acknowledged that the Janus program could put additional pressure on the country’s existing uranium supplies. “We expect sufficient prioritization to ensure that we have the uranium that we need for our fastest-moving reactors,” he said.

“This is really an all-of-government effort. We are tied in very closely with the folks at DOE and NNSA, trying to stand up new enrichment capability.”

The Army expects private investment to provide a significant portion of the financing needed to advance the reactor designs. Waksman said government funding from the Janus contracts is expected to represent only a fraction of the total investment required.

The milestone-based structure gives the Army flexibility to stop future payments if companies fail to meet technical requirements.

“These contractual milestones are very flexible,” Waksman said. “So if a company is not performing, if they are just disappointing, not delivering what we’re expecting, we can pull future milestones. There are no termination fees.”

Part of Wider Military Nuclear Effort

Janus builds on earlier Pentagon efforts to develop mobile nuclear power systems. The Army has taken lessons from Project Pele, a Defense Department initiative announced in 2022 to develop a transportable nuclear reactor weighing about 40 tons and capable of producing between 1 and 5 megawatts of electricity.

The Air Force is also pursuing a separate effort to develop a nuclear microreactor at Eielson Air Force Base in Alaska.

The Army’s latest initiative comes as the service looks more broadly at how to improve energy resilience for military operations. That includes efforts to develop mobile power systems capable of supporting counter-drone equipment, electronic warfare systems and directed-energy weapons.

The Army has also reconsidered some conventional approaches to supplying electricity at its installations. Earlier this month, officials said an agreement with the Tennessee Valley Authority on the use of green energy had been scrapped as the Army examines other options, including greater use of natural gas.

For now, however, the Janus program represents one of the Army’s most ambitious attempts to introduce nuclear power directly into its military infrastructure.

If the program succeeds, the service expects small nuclear reactors to provide a long-term source of electricity that can operate independently of vulnerable external power and fuel networks. The immediate goal is to prove that the technology can work safely and reliably at U.S. military bases before considering wider deployment.