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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.
Ung-Soo Kim, Poong-Hyun Seong
Nuclear Technology | Volume 141 | Number 2 | February 2003 | Pages 157-166
Technical Paper | Nuclear Plant Operations and Control | doi.org/10.13182/NT03-A3357
Articles are hosted by Taylor and Francis Online.
In this research, lower shifted worth control rods (LSWCRs) are suggested to mitigate problems related to variation of axial power distribution during the power maneuvering of pressurized water reactors. These rods are classified into two types. The first type is "multipurpose control rod," and the other type is "regulating control rod." Two multipurpose control rod banks (LSWCR1, LSWCR2) and three regulating control rod banks (LSWCR5, LSWCR4, LSWCR3) are suggested and developed. The moving characteristics of LSWCRs, related to variation of reactivity and the axial offset (AO), are analyzed, and the operation strategy for LSWCRs is established. Then, an application of LSWCRs for the power maneuvering is performed using the developed strategy, and the reference daily load pattern is 100-50-100%, 2-6-2-14h pattern that is appropriate for operation of the electric grid in Korea. From the results, it is shown that the combinative use of multipurpose control rods (LSWCR1, LSWCR2) makes it possible to control the AO within the target band during the power maneuvering. Also, the results show that the power maneuvering without reactivity compensation by change of boron concentration is accomplished, and consequently the minimization of boron concentration change is possible.