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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.
Ki-Yong Ra, Byong-Whi Lee, Soon-Heung Chang
Nuclear Technology | Volume 101 | Number 2 | February 1993 | Pages 149-158
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT93-A34776
Articles are hosted by Taylor and Francis Online.
With most of the current probabilistic safety criteria (PSCs), it is difficult to select a unanimously acceptable single-point safety goal and to evaluate the uncertainties in the results of a probabilistic safety assessment (PSA). A new PSC is proposed, in which the distribution of the public’s safety goals (DPSG) is used as a benchmark for evaluating the results of a PSA rather than a single-point safety goal. With this approach, the DPSG and the uncertainties in the results of a PSA can be handled properly so as to give a clear answer of “how much of the public feels a nuclear reactor is safe” to the question of “How safe is safe enough?” The proposed PSC is compared with the current PSCs and the expected utility model. If the actual DPSG is unavailable or difficult to obtain directly, a lognormal distribution is recommended as an appropriate DPSG for core melt frequencies in terms of maximizing entropy and minimizing total social cost. The proposed DPSG and PSC for core melt frequency are applied to the results of NUREG-1150.