Nuclear heat storage and recovery for the APR1400

Abstract

Detailed here is the proposed design of the tertiary side of a Thermal Energy Storage (TES) System to be interfaced with the steam cycle of a Light Water Reactor (LWR) plant. This study extends the understanding provided by many previous investigations (i.e., beyond thermodynamic considerations) by specifically addressing real world constraints associated with the backfit of such a system to an operating LWR. These constraints relate to the feasibility of design modifications during an extended refueling outage, and to licensing, operational, and maintenance considerations. The Korean designed and built APR1400 plant is selected for integration with the TES tertiary system, resulting in a design which can be readily be adapted to most LWR plant. Heat transfer and transport from and to the nuclear steam cycle is by synthetic oil with high temperature capabilities. Heat storage is in the form of packed beds consisting of crushed rock. While the rates of storage and recovery are constrained by the design of the nuclear reactor and steam plant (i.e., 20% of reactor thermal power during storage, and ~11% during recovery) the total stored energy component of the system can be readily and economically scaled to any desired capacity (at the marginal cost of carbon steel vessels filled with rock). Finally, it is proposed that any nuclear installation with water access could employ bulk thermal energy storage built into an Ultra Large Barge for turnkey delivery with a concomitant reduction in installed cost and risk.