Integrated thermohydraulic transient testing of steam extraction loop system to support joint electricity-hydrogen production using generic boiling water reactor

The economic competitiveness of the current fleet of light water reactors may be improved by coupling nuclear reactors to industrial facilities. This will allow flexible use high-quality steam or electric power from the reactor when the cost of electricity is low compared to the generation cost. One promising application is hydrogen production. Understanding the nuclear plant response to steam offtake is important for safe operation of the reactor facility. Conceptual analysis has been performed for coupling pressurized water reactors (PWRs) to high temperature steam electrolysis hydrogen production; however, corresponding work done for boiling water reactors (BWRs) has not been published, even though BWRs make up 30% of the US operating fleet. This paper demonstrates the feasibility of coupling a generic BWR to a hydrogen production facility. The system response is analyzed for a 15% reduction in the electrical power output. This work shows that when steam is extracted from the main steam header without appropriate controls modifications, reactor power will increase beyond 100% rated power. We present addition analysis to maintain power below rated conditions by varying feedwater recirculation pump speeds.