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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.
Ana C. Fernandes, Isabel C. Gonçalves, Nuno P. Barradas, António J. Ramalho
Nuclear Technology | Volume 143 | Number 3 | September 2003 | Pages 358-363
Technical Note | Fission Reactors | doi.org/10.13182/NT03-A3423
Articles are hosted by Taylor and Francis Online.
The Monte Carlo code MCNP-4C was used to calculate the effective multiplication coefficient of a core configuration of the Portuguese Research Reactor (RPI) and the neutron fluxes in the core and in the reflector region.A comparison of the results obtained with MCNP and with the deterministic codes WIMSD-5 and CITATION was made. Consistent deviations of 2% for the effective multiplication constant and 8 to 28% for the neutron flux, depending on the energy range, were observed.Thermal, epithermal, and fast neutron flux measurements were performed using activation detectors. The calculations agree with experimental values within <15%; therefore, the Monte Carlo results can be used to predict the neutron field in other locations and irradiation facilities of the RPI.