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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.
Jason Chao, William H. Layman, Gary Vine
Nuclear Technology | Volume 76 | Number 1 | January 1987 | Pages 113-125
Fourth International Retran Meeting | Heat Transfer and Fluid Flow | doi.org/10.13182/NT87-A33903
Articles are hosted by Taylor and Francis Online.
Several scram setpoints were analyzed for the purpose of reducing scram frequency in a Westinghouse four-loop plant. The results showed that the low-low steam generator (SG) level setpoint can be eliminated when reactor power is 50% or less during a loss of heat sink (LOHS) event. (The LOHS is the basis of this setpoint.) Without this setpoint, the reactor can still scram safely on either high pressurizer pressure or high pressurizer level without lifting the safety valves. The scram signal on the low SG level in coincidence with the signal from a mismatch of steam flow and feedwater flow can also be removed with no adverse effect on safety. This setpoint has never been included in the safety analysis. The results also showed that the power level above which the reactor should be scrammed when there is a turbine trip can be raised from its current value of 10% power to 50% when the condenser is available.