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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.
Alisha Kasam-Griffith, Milos Atz, Tingzhou Fei, Zhaopeng Zhong, Michael Jarrett, Florent Heidet
Nuclear Science and Engineering | Volume 196 | Number 1 | October 2022 | Pages S38-S49
Technical Paper | doi.org/10.1080/00295639.2022.2031712
Articles are hosted by Taylor and Francis Online.
Successful operation of the Versatile Test Reactor (VTR) relies on satisfying stakeholder requirements and guaranteeing customer timelines. Although the VTR leverages proven sodium fast reactor technology, its mission as a test reactor introduces unique design and operational requirements. This paper covers the preliminary analysis and methodology development for two areas of the VTR core design related to the operational flexibility necessary for the testing mission. The first of these introduces a framework for assessing the feasibility of storing used driver fuel in the VTR shield region, which offers potential benefits to operations but may affect core reactivity and increased cooling time. A methodology to assess these impacts using neutronics and depletion calculations is demonstrated on three in-shield storage configurations. The second focus area highlights operational considerations and maximum residence time of the VTR control assemblies, which are critical to maintaining the irradiation environment necessary to deliver on the VTR mission. A preliminary methodology that assesses B-10 depletion and absorber rod swelling is demonstrated with the goal of informing future development. Together, these research activities illustrate how the early-stage VTR design is guided by anticipation of operating objectives.