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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.
Atul A. Karve, Chae Han, Rizwan-uddin
Nuclear Technology | Volume 123 | Number 2 | August 1998 | Pages 121-129
Technical Paper | Fission Reactors | doi.org/10.13182/NT98-A2886
Articles are hosted by Taylor and Francis Online.
Axial power shapes that develop during power-maneuvering simulations in pressurized water reactors must be analyzed to ensure that an adequate margin to avoid departure from nucleate boiling (DNB) is maintained during these transients. To reduce the number of flux shapes that need to be analyzed in detail to determine the DNB ratio (DNBR), often generic axial flux shapes are analyzed and maximum-allowable-peaking (MAP) limits are determined to conservatively filter those actual axial power shapes that are clearly safe. Current generic MAP limits, obtained for axial flux shapes generated by a two-parameter-based axial flux shape generator, are overly conservative for some power shapes and are nonconservative for others, leading to unnecessary operational restrictions on conservative cases. A penalty is imposed on nonconservative cases. To reduce the number of overly conservative and nonconservative cases, a new generic axial power shape generator that is based on three parameters is developed. Generic MAP limits have been developed for the new axial flux shape generator and tested using real flux shapes by plotting the percent deviation of MAP limits for generic flux shapes from the corresponding value for actual flux shapes. A new axial flux shape generator, which is clearly superior because it leads to a significantly lower percent deviation, will lead to reduced man-hours for detailed DNBR analyses and remove some of the unnecessary operational restrictions imposed by the old flux shape generator.