The U.S. Army has mobilized up to $2.2 billion for a five-year effort to build and operate more than 20 commercial nuclear microreactors across military installations, selecting five reactor developers and five initial sites for a program designed to push advanced nuclear systems beyond federal test programs and into sustained operation.
On Aug. 26, the Army selected Antares Nuclear for Fort Bragg in North Carolina, BWXT Advanced Technologies for Fort Campbell in Kentucky, General Atomics Electromagnetic Systems for Fort Hood in Texas, Radiant Industries for Fort Benning in Georgia, and Westinghouse Government Services for Fort Drum in New York.
Radiant disclosed the largest agreement so far—up to $750 million to deploy 15 factory-built, 1-MWe Kaleidos microreactors by 2030, beginning with a three-unit installation at Fort Benning. Antares will also deploy reactors in three-unit groups, beginning with its 100-kWe-to-1-MWe R1 at Fort Bragg. Both companies are advancing reactor designs that use tri-structural isotropic (TRISO) particle fuel and will leverage testing underway at Idaho National Laboratory (INL).
The other three selections are larger, single-microreactor installations. BWXT plans a 20-MWe version of its 75-MWth BWXT Advanced Nuclear Reactor (BANR) at Fort Campbell, where it is targeting construction in late 2028 and operation in the early 2030s. General Atomics plans to advance its liquid-metal-cooled General Atomics Tactical Energy System (GA-TES), which has a baseline output of about 5 MWe and can scale to about 20 MWe, through development, testing, and site-planning work at Fort Hood “toward potential deployment.” Westinghouse Government Services will deploy its eVinci heat-pipe microreactor at Fort Drum, though the company did not disclose the specific output, schedule, or contract value.
The five companies will own, build, and operate the reactors under fixed-price, milestone-based Other Transaction Authority agreements negotiated through the Department of War Innovation Unit (DIU), the Pentagon organization charged with accelerating military adoption of commercial technology. The agreements implement directives from a series of presidential executive orders issued in May 2025, which designated the Army as the Pentagon’s executive agent for installation nuclear energy and required it to have at least one Army-regulated reactor operating at a military installation by Sept. 30, 2028.
A key objective is to use military demand and operating experience to establish reactor products that vendors can later sell to customers beyond the military, said Dr. Jeff Waksman, principal deputy assistant secretary of the Army for Installations, Energy and Environment. “What we’re trying to transition is from experiments and prototypes to actual commercial products. That is the transition that we are trying to affect here.”
“To be clear, these companies have negotiated significantly different numbers of reactors. They have different amounts of money,” Waksman explained during an Aug. 26 media roundtable. “We have not divided the money evenly five ways, but again, this is about the flexibility that we have to do what we think is most beneficial to the government. We don’t expect all five of these companies are going to turn on a reactor in 2028. In fact, they definitely will not. But we do believe we have a very practical pathway to delivering at least one of these reactors on by September 30, 2028, which was the date set in the executive orders.”
The milestone agreements collectively span fiscal years 2027 through 2031, and each company has fixed-price milestones extending through at least one completed, operating reactor. Government payments are conditioned on successful completion of agreed technical goals, and the Army may remove future milestones from companies that fall behind, redirect funding to stronger performers, or add another vendor later, officials said. The structure does not require a fixed government-to-private cost share, but Waksman said the Army expects billions of dollars in private financing, which it anticipates will account for most of the total investment in the reactor programs.
Ultimately, the first reactor must provide useful, reliable electricity to an Army installation. “You can just say, ‘Oh, turn a reactor on,’ and then build a little criticality experiment to claim that that’s success,” Waksman said. “That is not success for us. The intent here is that these reactors have to provide useful, reliable power to these installations.”
Five Companies, Five Initial Installations
The selections followed a competition that narrowed a larger group of bidders to 10 finalists. Experts from the Department of Energy (DOE), national laboratories, academia, the private sector, and the military services then subjected each finalist to four hours of questioning, Waksman said.
The Army declined to disclose an exact breakdown of the aggregate $2.2 billion, noting that the totals may change over time and that its milestone-based OTA contracts allow funds to be reallocated among vendors as the program progresses. However, several companies provided additional details to POWER.
Radiant Secures Up to $750M to Deliver 15 Kaleidos Units
Radiant Industries secured a binding Janus agreement worth up to $750 million to develop and deploy 15 Kaleidos microreactors across U.S. military installations by 2030. The company described it as the largest Janus award and one of the largest contracts ever issued through the DIU. The first three-unit deployment is planned for Fort Benning, Georgia, while additional reactors will go to other military sites. Radiant told POWER that its first Janus units are expected to begin supplying resilient power in 2028.
“The U.S. Army is a savvy customer. They have the world’s top nuclear experts and know what to look for in a partner,” said Tori Shivanandan, Radiant’s president and chief operating officer. “The numbers tell the story. This award shows confidence in Radiant’s product and ability to manufacture, deploy, and safely operate nuclear microreactors for the American military.”
The 1-MWe Kaleidos is factory-built and designed to arrive as a sealed, fueled unit. It can travel by land, sea, or air, requires no cooling water, and has a 20-year operating life. Radiant says each unit can operate for up to five years before refueling, and additional reactors can be added or relocated as power requirements change.
Radiant is building its 300,000-square-foot R-50 manufacturing, fueling, and storage campus in Oak Ridge, Tennessee. The company plans to manage fueling, refueling, and spent-fuel storage away from customer installations, which will not host spent fuel. Radiant says an installation can return to greenfield condition within two years after a reactor is removed.
Kaleidos has shipped to Idaho National Laboratory’s Demonstration of Microreactor Experiments (DOME) facility, where it is being prepared for testing. DOE granted Radiant exclusive access to DOME for one year to conduct a full-scale, full-power, extended-duration test using the reactor design and fuel specifications planned for customer deployments.
Radiant’s fuel pathway separates enriched uranium supply from reactor-ready fuel fabrication. DOE-allocated high-assay low-enriched uranium (HALEU) will support Kaleidos deployments under both Janus and ANPI, and Standard Nuclear will fabricate that material into TRISO particle fuel under a binding, multi-metric-ton agreement announced Aug. 20 and extending through 2031. Radiant said the Standard Nuclear agreement addresses a separate risk from access to enriched uranium. “Having access to HALEU does not by itself give you reactor-ready fuel; you also need the specialized fabrication capability to turn that material into qualified TRISO fuel at the specifications and volumes the reactor requires,” the company said. “By putting a long-term fabrication agreement in place, Radiant has secured that downstream capability for its planned deployments through the early 2030s, including for both government and commercial customers.”
The Janus agreement substantially expands Radiant’s military deployment program beyond its earlier Air Force Advanced Nuclear Power for Installations (ANPI) selection at Buckley Space Force Base in Colorado, and it feeds directly into the same product Radiant is building for commercial customers, including a signed agreement with Equinix for 20 Kaleidos units.
“What Janus changes for Radiant is the scale,” the company told POWER. “Every additional reactor in operation generates operating experience across different sites, operating environments and use cases, allowing Radiant to build an operational track record that all customers need to see to procure any product at scale. Essentially, we are able to collect one year of operational data for each reactor—when 15 are running, that means we have 15 years’ worth of operational data after one calendar year. This is not a long-term R&D program. It’s an accelerated program to deliver a capability that the military can then buy at tremendous scale.”
Antares Wins Fort Bragg for Its R1 Three-Pack
Antares Nuclear, founded in 2023 and based in Torrance, California, will own, build, and operate a three-unit R1 microreactor deployment at Fort Bragg, home of the 18th Airborne Corps. The company declined to disclose its Janus contract value directly but confirmed that its combined book across the Janus program, the Air Force ANPI initiative at Joint Base San Antonio, and Space Force nuclear work is now “on the order of $1 billion,” according to Chief Executive Jordan Bramble.
R1 is a sodium heat-pipe-cooled microreactor fueled by TRISO particle fuel, rated at 100 kWe to 1 MWe per unit, and designed for years of operation between refuelings. The company said R1 requires no connection to the commercial grid or specialized infrastructure to deploy—a design posture consistent with the Janus program’s remote-installation resilience use case. R1 draws directly on Antares’ Mark-0 test reactor at INL, which achieved criticality on June 4, 2026, the first advanced reactor to reach criticality under the DOE Reactor Pilot Program. Antares said it remains on track to generate electricity from a test reactor in 2027 and to deploy initial production units to U.S. military installations beginning in 2028.
Fuel supply is dual-sourced. The company said it anticipates sourcing TRISO from Standard Nuclear and BWXT, an architecture that may bolster both U.S. industrial-scale TRISO fabrication lines and hedge Antares against a single-supplier bottleneck. Antares did not name a utility partner for Fort Bragg or subcontractors on the R1 system. The company operates additional facilities in Idaho Falls, Idaho, and Aiken, South Carolina.
“We’re grateful and proud to partner with the U.S. Army and the Defense Innovation Unit on the Janus Program. Energy scarcity is constraining America’s most critical defense systems,” Bramble said. “Through Janus, Antares will deliver clean, firm, resilient power for the warfighter.”
BWXT Takes Fort Campbell With a 20-MWe BANR
BWX Technologies subsidiary BWXT Advanced Technologies will deploy the BWXT Advanced Nuclear Reactor (BANR) at Fort Campbell, Kentucky, straddling the Kentucky-Tennessee line and home to the 101st Airborne Division. The Janus BANR is a 20-MWe unit, scaled up from the 1.5-MWe Project Pele microreactor that BWXT has been building for the Department of War since 2020. It represents the commercialization arm of a two-track microreactor program the company has run in parallel with Pele under DOE’s Advanced Reactor Demonstration Program (ARDP), Joe Miller, president of Government Operations, told POWER.
BWXT did not disclose the value of its Janus agreement, but the company confirmed a phased contracting structure. Phase 1 covers final site selection within Fort Campbell, starting Army-owned nuclear regulatory work, kicking off TRISO fuel fabrication at existing BWXT facilities, operating-company structuring, site characterization, and long-lead procurement. Groundbreaking is targeted for late 2028 and reactor operations for the early 2030s. Miller told POWER BWXT expects to deliver within roughly five years of the start.
BANR is a high-temperature gas-cooled reactor using TRISO fuel and a nitrogen primary coolant, with a thermal rating of 75 MWth and core outlet temperatures near 600C. Its fuel is uranium oxycarbide TRISO enriched to 19.75%, and it requires a roughly four-year refueling cycle. Unlike Pele, BANR is designed as a steam-cycle plant on the non-reactor side, giving it more efficient conversion and broader use cases while retaining the HTGR primary loop, Miller said. The design supports cogeneration or all-electric operation and is factory-built for road- and rail-shippable modules. At multi-unit scale, BWXT markets 100 MWe on under 15 acres, and a single reactor can be located on less than five acres. Once sited, a BANR is not transportable in the Pele sense—”you wouldn’t move it like you would a Pele reactor,” Miller noted. At Fort Campbell, BWXT is prioritizing behind-the-meter service but plans to design in the option to export power to surrounding communities, Miller said.
BWXT, notably, is the only Janus vendor that self-supplies its TRISO fuel. Its NRC-licensed Lynchburg, Virginia, facility fabricated the roughly 40,000 TRISO compacts delivered to INL for Project Pele in November 2025. The company has also authorized more than $25 million to more than double Lynchburg output as a near-term bridge, and it is negotiating a several-hundred-million-dollar commercial TRISO facility in Wyoming’s Trona Patch that would add roughly tenfold operational output relative to Lynchburg’s current capacity, Miller said. BWXT has also produced TRISO fuel for Antares and Radiant in the past, and Miller said BWXT expects to continue supplying Antares and Westinghouse under commercial agreements.
Northrop Grumman and Rolls-Royce are subcontractors on system delivery, which will give BWXT a prime role that extends past the reactor and fuel to the balance of plant, Miller said. Notably, the Fort Campbell team also includes a utility partner that BWXT declined to identify, though Miller described the company as “one of the aggressive type utilities out there that are taking new nuclear extremely seriously.” Burns & McDonnell has performed site and infrastructure work on BANR deployment configurations, including cost-shared studies with the state of Wyoming, he noted.
Beyond Janus, BWXT has signaled a commercial pipeline that includes a letter of intent from Tata Chemicals Soda Ash to explore up to eight BANR units in Wyoming. The company is also preparing an NRC manufacturing license (ML) application, which it says would target under 24 months of review and low-$10-million per-customer review costs by shifting more design review into the factory—a filing BWXT argues can build on Army-owned qualification work performed under Janus.
“Our long-standing strengths in reactor engineering innovation, TRISO fuel development, and advanced nuclear manufacturing are the foundation of our BANR technology,” said BWXT President and Chief Executive Officer Rex D. Geveden. “As we commence work on the Janus program, we are delivering the nation’s most credible and reliable path to deployable nuclear power. BANR is purpose-built for mission success.”
General Atomics Advances GA-TES at Fort Hood
General Atomics Electromagnetic Systems (GA-EMS), the San Diego-based General Atomics subsidiary, will advance its General Atomics Tactical Energy System (GA-TES) at Fort Hood, Texas, home of III Armored Corps, through development, testing, and site-planning milestones toward potential deployment. Contract value was not disclosed.
GA-TES is the only announced Janus reactor that does not use TRISO particle fuel. The design uses uranium-zirconium hydride (UZrH) fuel, drawn directly from General Atomics’ TRIGA research reactor heritage—68 TRIGA reactors have been deployed globally over more than 70 years, with a documented history of self-regulating negative temperature reactivity behavior. GA-TES is liquid-metal-cooled by natural circulation, requires no large cooling-water infrastructure, is rated at approximately 5 MWe baseline and scalable to approximately 20 MWe, and is designed for a 40-year operating life. Its modular architecture supports transport by truck or rail and targets remote, austere, off-grid, and extreme-environment applications, as well as on-site power during grid disruptions, according to the company.
The company did not disclose a fuel supplier, though General Atomics has in-house UZrH fabrication capability tied to its TRIGA program. The company did not name a utility partner for Fort Hood, which is located in the ERCOT footprint.
“General Atomics draws on more than 70 years of nuclear innovation and reactor expertise to deliver microreactor technologies that provide safe, dependable and independent power for military installations,” said Scott Forney, president of GA-EMS. “Our experience designing and deploying 68 reactors worldwide and supporting reactor technologies throughout their lifecycles positions us to deliver assured energy solutions that enhance operational resilience and strengthen mission readiness.”
“Passive safety and operational simplicity are fundamental to our Tactical Energy System design,” added Christina Back, GA-EMS vice president for nuclear technologies and materials. “Self-protecting UZrH fuel and pump-free natural-circulation cooling reduce reliance on active systems and operator intervention.”
Westinghouse Brings eVinci to Fort Drum
The Army selected Westinghouse Government Services to deploy the eVinci microreactor at Fort Drum, New York, home of the 10th Mountain Division. Westinghouse confirmed the selection to POWER, though it did not disclose reactor output, schedule, or contract value.
eVinci is a heat-pipe microreactor designed to deliver electricity 24 hours a day, 7 days a week for eight years without refueling, Westinghouse said. Notably, the design achieved zero-power criticality at the National Criticality Experiments Research Center, a National Nuclear Security Administration facility at the Nevada National Security Site, on Aug. 24 at 10:39 a.m. PT—two days before the Janus announcement. The company completed the test in partnership with Los Alamos National Laboratory and INL. Westinghouse is also an ANPI selectee at Malmstrom Air Force Base, Montana. The Fort Drum selection follows a mid-August letter from Sen. Chuck Schumer (D-N.Y.) to Secretary of the Army Dan Driscoll urging that the installation be prioritized.
“Reliable energy is fundamental to mission assurance, operational readiness and national security,” said Rich Rademacher, president of Westinghouse Government Services. “The selection of the eVinci microreactor for the Janus Project highlights the important role advanced nuclear technology can play in providing resilient, long-duration power to the warfighter. Westinghouse is proud to support the Army’s efforts to strengthen energy security and deliver innovative capabilities.”
—Sonal Patel is a POWER senior editor (@sonalcpatel, @POWERmagazine).
This is a developing story. POWER will update with additional detail on contract values, schedules, and reactor configurations as vendors and the Army disclose them.