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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.
J. A. Mowrey, S. I. Abdel-Khalik, K. W. Ross
Nuclear Technology | Volume 111 | Number 2 | August 1995 | Pages 283-302
Technical Paper | Nuclear Criticality Safety Special / Reactor Operation | doi.org/10.13182/NT95-A35138
Articles are hosted by Taylor and Francis Online.
A RELAP5/MOD3.1 model of a boiling water reactor and an interface are developed as a real-time test platform for a physical feedwater control system and turbine governors. The reactor plant modeled is Browns Ferry unit 2. The model is used to test and tune the new digital reactor feedwater control system (RFWCS) for units 2 and 3. The set of modeled components, trips, and controls is determined based on the testing requirements for the RFWCS. The work is performed in two phases. In the first phase, the existing plant is modeled, including the previously existing analog feedwater control system and governor. The resulting RELAP5 model is benchmarked against existing plant data. Benchmarking results are presented along with data on initialization to steady state. Once the benchmarking effort is completed, the control systems in the model are altered to allow testing of the digital RFWCS in real time. An interface is developed to allow communications with the digital RFWCS and operator interaction, which allows the test platform to be used to determine control system response to various transients. Descriptions of the RELAP5 model and hardware and software for the interface are provided.