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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.
Man-Sung Yim, John M. Christenson
Nuclear Technology | Volume 100 | Number 3 | December 1992 | Pages 361-377
Technical Paper | Reactor Operation | doi.org/10.13182/NT92-A34731
Articles are hosted by Taylor and Francis Online.
The control characteristics of a load-following pressurized water reactor are investigated through the application of a nonlinear optimization method to a simplified plant simulator. A model describing the power level control and power distribution control is developed and used to formulate an optimal control problem. In the optimal control problem formulation, all of the safety and system operating limits are included as hard constraints, and the multiple objective functionals are combined into a single performance index. The differences in the calculated optimal load-following control strategies are investigated for the cases of steady-state Tavg (coolant average temperature) program operation and variable Tavg operation at both beginning-of-cycle and near end-of-cycle conditions. The results show that the amount of boron control action for the demanded load variations can be significantly reduced when variable Tavg operation is incorporated into the control policy.