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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.
A. R. Wazzan, A. Villalobos, D. Okrent
Nuclear Technology | Volume 70 | Number 2 | August 1985 | Pages 285-289
Technical Note | Fission Reactor | doi.org/10.13182/NT85-A33654
Articles are hosted by Taylor and Francis Online.
A computer code developed earlier by Villalobos et al. to predict fission gas behavior in uranium oxide fuel under steady-state irradiation conditions and where bubble gas resolution is represented with the single knock-on model (SKO) is modified to replace the SKO model with the complete bubble destruction model (CBD). The CBD model required that bubble nucleation be included in the present analysis. The revised code is used to compute gas release and total swelling. Both are found to be insensitive to whether they are obtained with the CBD or the SKO option. This is mainly because at low atomic percent of burnup, total swelling is dominated by the grain-edge bubble gas contribution, and release is dependent on the formation of a complete grainface/grain-edge tunnel network—factors that are not much affected by either the SKO or CBD models. At higher atomic percent of burnup, intragranular swelling, which can be sensitive to the resolution model, contributes more to swelling. But even then, computations at 1.0 at.% burnup suggest total swelling will continue to be dominated by grain-edge gas. These results suggest that in modeling swelling and release in irradiated uranium dioxide fuel, the simpler SKO resolution model is satisfactory.