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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.
Gabriel Kooreman, Farzad Rahnema
Nuclear Technology | Volume 192 | Number 3 | December 2015 | Pages 264-277
Technical Paper | Radiation Transport and Protection | doi.org/10.13182/NT14-150
Articles are hosted by Taylor and Francis Online.
The hybrid Diffusion-Transport Homogenization (DTH) method has been improved by replacing the assembly-level fixed-source calculation step with a fixed number of whole-core transport sweeps following each homogenization step. Like the unmodified DTH method, the Enhanced hybrid Diffusion-Transport Homogenization (EDTH) method adds an “auxiliary cross-section” term to the right side of the transport equation in order to maintain consistency with the heterogeneous equation. As an improvement to the DTH method, the on-the-fly rehomogenization step of the EDTH method utilizes a fixed number of full-core transport sweeps in lieu of assembly-level fixed-source heterogeneous transport calculations. The EDTH method has been tested in one-dimensional reactor core benchmark problems typical of a boiling water reactor core, a gas-cooled thermal reactor [High Temperature Test Reactor (HTTR)] core, and a pressurized water reactor core with mixed-oxide fuel. The method has been shown to reproduce the heterogeneous transport flux profile with 0 to 46 pcm eigenvalue error and 0.1% to 1.8% mean relative flux error with a speedup factor of 1.4 to 4.5 times faster than the DTH method. This represents a speedup of 3.0 to 12.5 times compared to fine-mesh transport.