en.Wedoany.com Reported - The first fuel for Radiant's Kaleidos microreactor technology, intended for full-power, full-temperature testing, has arrived at the Demonstration of Microreactor Experiments (DOME) facility at the National Reactor Innovation Center (NRIC) at the Idaho National Laboratory (INL) in the United States.
This batch of tristructural isotropic (TRISO) fuel was manufactured by Standard Nuclear according to Radiant's specifications and delivered earlier in 2026. The company stated that the fuel will be used to power the Kaleidos reactor, with full-power, full-temperature testing planned for the summer of 2026, followed by several months of rigorous testing and validation. With the fuel now on site, the company is ready to proceed with starting up the Kaleidos reactor.
Radiant will implement a five-phase reactor development test program at the DOME facility to collect critical reactor and fuel performance data. The company says this data will help accelerate the commercial licensing process with the U.S. Nuclear Regulatory Commission (NRC). The test program will sequentially progress through zero-power criticality, 1 MWt thermal power, and full-power phases, with the ultimate goal of operating at full power for at least 150 hours without operator intervention—a key milestone for demonstrating commercial maturity.
The DOME test bed is a 100-foot-tall (approximately 30 meters), 80-foot-diameter (approximately 24 meters) facility that utilizes the containment structure of the Experimental Breeder Reactor-II (EBR-II), which operated from 1964 to 1994. The facility provides a safe environment for testing experimental reactor concepts and collecting performance data that can support future commercial license applications, thereby accelerating development timelines, saving costs, and reducing project risk.
Radiant's Chief Nuclear Officer, Rita Baranwal, stated that the company is de-risking a commercial product that will be manufactured and delivered within 18 months. Receiving newly manufactured, custom fuel using modern processes is a key milestone in achieving this goal. Radiant is strictly adhering to specifications in the DOME test program, testing prototype fuel, coolant, and power levels to validate product performance and ensure successful delivery to customers by 2028.
Data collected from DOME will also play a critical role in supporting Radiant's application for a Part 70 license under Title 10 of the U.S. Code of Federal Regulations for its R-50 manufacturing facility in Tennessee, which is currently under accelerated review by the NRC. Once approved, this license will enable Radiant to handle and load fuel for its Kaleidos reactors, which will then be shipped to customers across the United States, enabling standardized batch production.
Kaleidos is a high-temperature gas-cooled reactor that uses TRISO fuel, helium coolant, and prismatic graphite blocks. This transportable microreactor will be fully contained within a standard shipping container, designed for a thermal power of 3 MWt and an electrical power of approximately 1 MWe. Since 2022, the NRC has been engaged in pre-application activities with Radiant regarding this reactor. Kaleidos was one of three microreactor designs selected in 2023 to receive U.S. federal funding support for front-end engineering and experiment design at DOME.
