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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.
Hirokazu Ohta, Takanari Ogata, Dimitrios Papaioannou, Vincenzo V. Rondinell, Marc Masson, Jean-Luc Paul
Nuclear Technology | Volume 190 | Number 1 | April 2015 | Pages 36-51
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT14-50
Articles are hosted by Taylor and Francis Online.
An irradiation experiment on minor actinide (MA)-bearing uranium-plutonium-zirconium (U-Pu-Zr) alloys, in which contamination by rare earth (RE) elements was considered, was performed up to ~2.5 at. %, ~7 at. %, and ~10 at. % burnups in the Phenix fast reactor. All the irradiated metal fuel pins were subjected to nondestructive tests such as cladding profilometry and gamma spectroscopy. Then, cross-sectional metallography of the low-burnup and medium-burnup fuel alloys was performed, and the redistribution of the fuel matrix constituents—U, Pu, and Zr—in the low-burnup fuels was analyzed by energy dispersive X-ray spectroscopy. As a result, the irradiation growth of MA-rich and RE-rich precipitates was observed by comparing the low-burnup and medium-burnup fuels. From the postirradiation examinations carried out so far, it was confirmed that the irradiation swelling, the cross-sectional structures, and the migration of matrix constituent in metal fuels containing 5 wt% or less MAs and REs are almost the same as those in conventional U-Pu-Zr fuels.