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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.
Bela Toth, Klaus Mueller, Jon Birchley, Hozumi Wada, Claude Jamond, Klaus Trambauer
Nuclear Technology | Volume 157 | Number 2 | February 2007 | Pages 132-142
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT07-A3808
Articles are hosted by Taylor and Francis Online.
This paper presents the results of pretest calculations of the Phebus fission product release experiment FPT3. The test scenario with the appropriate initial and boundary conditions was provided by the Institut de Radioprotection et de Sûreté Nucléaire. For the analyses, three severe accident codes were used: ATHLET-CD, ICARE2, and MELCOR. The calculations were focused on the main phenomena occurring in the bundle, such as the thermal behavior, the hydrogen production mainly due to cladding oxidation, the massive degradation of spent fuel and the release of fission products and control rod and structure materials. Using the predefined boundary and initial conditions, relatively small deviations between the code results were obtained, which demonstrates that the dominant processes occurring during a severe accident in the core of pressurized water reactors can be adequately simulated. By applying these codes to a large spectrum of integral tests as well as to plant analyses, one will obtain reliable results on the fuel bundle behavior. However, the spread in the calculated oxidized boron carbide masses indicates that modeling efforts are still necessary in all the codes in this respect.