The Department of War’s (DOW) Project Pele has reached a significant milestone with the delivery of its tri-structural isotropic (TRISO) particle fuel to Idaho National Laboratory (INL), setting the stage for formal system testing as early as 2027. This first-of-its-kind transportable nuclear microreactor prototype, developed under a DOD Strategic Capabilities Office (SCO) initiative, aims to demonstrate a high-temperature gas-cooled (HTGR) mobile microreactor manufactured by BWXT Advanced Technologies. The fuel, manufactured by BWXT Technologies and shipped from its Lynchburg, Virginia, facility, represents a culmination of over two decades of TRISO fuel development and qualification work.
The delivery of 40,000 TRISO fuel compacts to INL’s Transient Reactor Test Facility (TREAT) on Nov. 5, 2025, marks a substantial step forward for Project Pele. “This is real nuclear microreactor fuel delivered at its final destination, rather than some letter or memorandum promising to make fuel at a later date,” noted Dr. Jeff Waksman, principal deputy assistant secretary of the Army for Installations, Energy and Environment. The fuel’s arrival at INL is a critical prerequisite for the forthcoming demonstration phase, with site construction already underway since September 2025.
Project Pele is designed to produce 1 MWe to 5 MWe for INL’s Critical Infrastructure Test Range Complex (CITRC) electrical test grid for about three years. The completed transportable system, housed in four standard-sized shipping containers, is scheduled to be transported to INL in 2026. The project’s immediate payoff is expected to be for the Army’s Janus Program, announced in October 2025, which aims to deliver affordable, reliable, commercial nuclear power to ensure critical infrastructure has power even if the electric grid is disrupted.
The Janus program, launched under Executive Order 14299, directs the DOW to commence operation of an Army-regulated reactor at a domestic installation by Sept. 30, 2028. It will use a milestone-based contracting model, in partnership with the Defense Innovation Unit, to build commercially owned and operated microreactors. Waksman has pledged to personally oversee the program, emphasizing that Janus “is going to deliver real hardware, not PowerPoint slides” as the Army moves “at lightning speed to make next-generation nuclear power a reality.”
Project Pele’s journey from concept to demonstration reactor began in 2016, following a Defense Science Board study that identified the need for a mobile, reliable, resilient power source. The SCO moved forward with a full-scale HTGR mobile microreactor concept after a two-year reactor design competition. In April 2022, the DOW formally opted to proceed with Project Pele, and in June 2022, the SCO picked BWX Technologies’ HTGR-based design for the prototype.
The milestone is also significant for TRISO development, validating decades of U.S. government investment in TRISO qualification. The DOE’s Advanced Gas Reactor (AGR) Fuel Development and Qualification Program, initiated in 2002, established the technical basis for licensing TRISO fuel in new reactor designs. However, TRISO’s uptake has been constrained by fuel cycle economics and market uncertainty. BWXT’s Senior Director of Advanced Nuclear Fuels Joshua Parker explained that suppliers have long been stuck in a “chicken-and-egg” bind, requiring steady demand at ton-per-year levels to justify a purpose-built Category II TRISO plant.
As Project Pele moves forward, it is poised to shape the development of mobile nuclear energy, potentially revolutionizing power generation for both military and civilian applications. The successful demonstration of this technology could pave the way for broader adoption of advanced nuclear reactors, offering a reliable and resilient power source for critical infrastructure and remote locations. The lessons learned from Project Pele will be instrumental in the Janus Program and future nuclear energy initiatives, driving innovation and advancements in the sector.