US-based portable nuclear microreactor manufacturer Radiant has received its first shipment of custom-made tri-structural ISOtropic nuclear fuel at the Idaho National Laboratory to prepare for an upcoming 150-hour continuous endurance trial.
The material, which is delivered to the National Reactor Innovation Center’s Demonstration of Microreactor Experiments facility, is designated for the company’s 1-megawatt Kaleidos microreactor.
“It will be used to power Radiant’s Kaleidos reactor to conduct a full-power, full-temperature test this summer – kicking-off months of rigorous testing and validation, to support manufacturing and customer delivery by 2028,” said the company in a press release.
Radiant, as the exclusive company authorized to use the Idaho testing facility, is utilizing this space to initiate a structured evaluation process. This experimental sequence is designed to gather comprehensive documentation regarding how the reactor core and fuel behave under operational stress. The physical presence of the fuel at the laboratory enables the engineering team to begin the initial steps of the evaluation.
Validating product for customer deployment
“We are de-risking a commercial product that will be manufactured and delivered within 18 months,” said Dr. Rita Baranwal, chief nuclear officer at Radiant. “Receipt of our freshly fabricated, modern-pedigree, custom-made fuel is a key milestone toward that goal.”
“Radiant has been very disciplined with our testing program at the DOME; we are testing our prototypic fuel, coolant, and power levels to validate our product and ensure success for our customer deployment by 2028,” she added.
The technical logs and observations generated during these summer trials will serve as foundational data for Radiant’s regulatory filings. The company needs this information to advance its Part 70 license application with the US Nuclear Regulatory Commission.
This particular license governs the proposed R-50 manufacturing site located in Tennessee, which is currently undergoing an expedited federal review.
Securing the license will grant the company legal authority to load nuclear fuel into the microreactors directly inside the factory prior to distribution. Management intends for this centralized assembly method to establish a standardized production system for future units.
Adhering to projected manufacturing window
This testing phase follows a sequence of regulatory and financial steps completed over the past year. In February, the US Department of Energy approved the safety framework for the project through the Authorization Request for Kaleidos documentation. This formal safety clearance gave the company the legal mandate required to plan the high-temperature trials.
The Kaleidos unit itself produces electrical power alongside 1.9 megawatts of thermal energy. The secondary thermal output can be diverted to heat industrial buildings or run desalination equipment.
To operate in arid environments, the physical architecture eliminates the need for external water cooling. Instead, the design uses integrated fans and an outer air jacket to dissipate core heat through natural air convection.
The corporate timeline projects that the resulting data will validate the design sufficiently to allow commercial units to ship to customers within the projected manufacturing window.