ASSURED PEAK NUCLEAR GENERATING CAPACITY WITH HEAT STORAGE AND AUXILIARY COMBUSTIBLE FUELS

摘要

In a low-carbon world (nuclear, wind, solar, and hydro) there is the need for assured generating capacity-dispatchable electricity. Base-load reactors can provide variable electricity to the grid by (1) sending some of their output (steam) to storage at times of low electricity prices and (2) using stored heat to produce peak electricity at times of high electricity prices. Heat storage [steam accumulators, sensible heat, etc.] is less expensive than electricity storage [batteries, hydro pumped storage, etc.]. However energy storage systems (heat or electricity) can't provide assured capacity for extreme events, be it supply side (extended low-wind or low solar conditions in systems with high wind or solar capacity) or demand side (long periods of cold or hot weather). With heat storage systems there is the option to provide peak electricity output even if heat storage is depleted by heat addition using natural gas, biofuels, or ultimately hydrogen. The fuel consumption for assured capacity is small because most of the time the heat storage system meets peak electricity demands. If a heat storage system has been built, the incremental capital cost of assured peak electric generating capacity (water tube boiler for LWRs) is low because the peak power system associated with heat storage paid for the oversized generators, turbines, and condensers. Heat storage and assured peak generating capacity can result in large increases in plant revenue. Heat storage options and how auxiliary fuel can be used to assure peak generating capacity are described for steam cycles coupled to water-cooled reactors. There are a parallel set of options for other power cycles and reactor types. The heat storage and assured capacity systems also enable reliable low-cost heat to industry.