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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.
Harald Zänker
Nuclear Technology | Volume 86 | Number 3 | September 1989 | Pages 239-247
Technical Paper | Fission Reactor | doi.org/10.13182/NT89-A34292
Articles are hosted by Taylor and Francis Online.
Periods of continuously decreasing levels of fuel rod integrity due to debris-induced cladding damage, vibration-induced fretting wear of the cladding, etc., cause difficulties in the assessment of fuel rod performance from coolant activity data. The calculational models currently in use for this purpose in nuclear power plants are not sufficiently capable of indicating cases in which they are invalid. This can mislead reactor operators by misinterpretation of the coolant activity data, especially in situations where fast reactions are necessary. A quick test of validity is suggested to check the applicability of the currently available calculational models for estimating the number and average size of fuel rod defects. The criteria of applicability are the fission product total activity, the slope tanα in the relationship Ig(Ri/Bi) = tanαlg λi for the volatile fission product isotopes, and the activity of nonvolatile nuclides such as 239Np and the isotopes of ruthenium and cerium. The objective is to recognize immediately periods of continuously decreasing levels of fuel rod integrity in order to prevent complications in routine power plant maintenance as well as accident situations caused by more severe fuel rod degradation.
