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The deadline arrives: Checking in on the Reactor Pilot Program
On May 23, 2025, President Trump signed Executive Order 14301, “Reforming Nuclear Reactor Testing at the DOE,” which instructed the Department of Energy to create a Reactor Pilot Program (RPP)—a new system in which companies could pursue DOE authorization to build and test their first-of-a-kind nuclear technologies. EO 14301 set an ambitious goal for that program: three reactors achieving criticality by July 4, 2026.
Hangbok Choi
Nuclear Science and Engineering | Volume 137 | Number 1 | January 2001 | Pages 38-51
Technical Paper | doi.org/10.13182/NSE01-A2174
Articles are hosted by Taylor and Francis Online.
The fuel composition heterogeneity effect on reactor performance parameters was assessed by refueling simulations for three DUPIC fuel options of fuel composition heterogeneity control: fissile content adjustment, reactivity control by slightly enriched and depleted uranium, and reactivity control by natural uranium. For each DUPIC fuel option, the simulations were performed using 30 heterogeneous fuel types, which were determined by the agglomerative hierarchical clustering method. The heterogeneity effect was considered during the refueling simulation by randomly selecting fuel types for the refueling operation. The refueling simulations of the heterogeneous core have shown that the key performance parameters, such as the maximum channel power (MCP), maximum bundle power (MBP), and channel power peaking factor (CPPF), are close to those of the core that has a single fuel type. For the three DUPIC fuel options, the uncertainties of MCP, MBP, and CPPF due to the fuel composition heterogeneity are <0.6, 1.5, and 0.8%, respectively. This study has shown that the three DUPIC fuel options reduce the composition heterogeneity effectively, and the zone power control system has a sufficient margin to adjust the perturbations caused by fuel composition heterogeneity.