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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.
Mohamed S. El-Genk, Huimin Xue, Dmitry Paramonov
Nuclear Technology | Volume 105 | Number 1 | January 1994 | Pages 70-86
Technical Paper | Special on Nuclear Criticality Safety / Nuclear Reactor Safety | doi.org/10.13182/NT94-A34912
Articles are hosted by Taylor and Francis Online.
The thermionic transient analysis model is used to simulate the startup of the TOPAZ-II space nuclear power system in orbit. The simulated startup procedures are assumed for the purpose of demonstrating the capabilities of the model and may not represent an accurate account of the actual startup procedures of the TOPAZ-II system. The temperature reactivity feedback effects of the moderator, UO2 fuel, electrodes, coolant, and other components in the core are calculated, and their effects on the thermal and criticality conditions of the reactor are investigated. Also, estimates of the time constants of the temperature reactivity feedback for the UO2fuel and the ZrH moderator during startup, as well as of the total temperature reactivity feedback as a function of the reactor steady-state thermal power, are obtained.