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NRC approves TerraPower construction permit
Today, the Nuclear Regulatory Commission announced that it has approved TerraPower’s construction permit application for Kemmerer Unit 1, the company’s first deployment of Natrium, its flagship sodium fast reactor.
This approval is a significant milestone on three fronts. For TerraPower, it represents another step forward in demonstrating its technology. For the Department of Energy, it reflects progress (despite delays) for the Advanced Reactor Demonstration Program (ARDP). For the NRC, it is the first approval granted to a commercial reactor in nearly a decade—and the first approval of a commercial non–light water reactor in more than 40 years.
Joseph A. Christensen, R. A. Borrelli
Nuclear Science and Engineering | Volume 196 | Number 11 | November 2022 | Pages 1333-1348
Technical Paper | doi.org/10.1080/00295639.2022.2087832
Articles are hosted by Taylor and Francis Online.
This work uses evaluated criticality safety benchmarks to examine the effect of heterogeneity in high-assay low-enriched uranium (HALEU) systems. A subset of benchmarks selected based on their composition parameters is slightly modified to artificially introduce heterogeneity, and the difference in the effective multiplication factor between the homogeneous benchmark and the modified model is determined. The difference in the multiplication factor is evaluated for correlations against both the moderator ratio and the enrichment of the benchmarks, and the correlations are examined using established statistical methods. In several cases, statistically significant correlations are observed and discussed, and the lack of expected correlations is also discussed.