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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.
R. G. Gonzalez, F. D'Auria, O. Mazzantini
Nuclear Technology | Volume 194 | Number 1 | April 2016 | Pages 61-72
Technical Paper | doi.org/10.13182/NT14-155
Articles are hosted by Taylor and Francis Online.
Atucha-2 is a Siemens-designed pressurized heavy water reactor located in Argentina. Its geometrical complexity and peculiarity [e.g., oblique control rods (CRs) and positive void coefficient] required a developed and validated complex three-dimensional (3-D) neutron kinetics (NK) model. In the framework of the agreement between NA-SA (Nucleo-electrica Argentina Sociedad Anonima) and the University of Pisa, a detailed NESTLE (3-D NK code) model of the Atucha-2 nuclear power plant (NPP) was developed. This document summarizes the procedures for implementing oblique CRs into the RELAP5/NESTLE model: A particular arrangement of the RELAP5/NESTLE CR insertion mode for oblique CRs and an implementation into the homogenized two-group cross sections of ad hoc calculated correction factors (these parameters were obtained by previously executed Monte Carlo calculations) were developed. Some applications, among the scenarios selected to perform safety analysis (Final Safety Analysis Report) of the Atucha-2 NPP (CNA-II), are also reported: preliminary scram rod worth, analysis of a CR ejection accident, and a CR faulty withdrawal.