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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.
Kazuya Takano, Masahiro Fukushima, Taira Hazama, Takayuki Suzuki
Nuclear Technology | Volume 179 | Number 2 | August 2012 | Pages 266-285
Technical Paper | Fission Reactors | doi.org/10.13182/NT12-A14098
Articles are hosted by Taylor and Francis Online.
The present paper describes the evaluation of the control rod worth data obtained in the Monju restart core. The best-estimate value and its uncertainty are evaluated in detail. As in the criticality evaluation, data obtained in the previous test are evaluated in the same level of detail.Evaluated results of control rod worth are consistent among control rods at symmetrical positions for a random uncertainty. The experimental uncertainty is ±2%, where the dominant uncertainty originates from the delayed neutron parameters used in the period method.The correlation in the uncertainties is also evaluated among different control rods and tests. One can discuss a difference in worth among different control rods and cores without a detailed knowledge of the original uncertainty evaluation.Based on the evaluated data, calculation accuracy is investigated with JENDL-3.3 and JENDL-4.0. It is confirmed that the calculation accuracy is within an experimental uncertainty of ±2% for each layer and 10B content.