Study of dynamic performance of radiation collector and thermocline system under time-varying radiation environment

The dynamic processes of coworking between thermocline thermal storage single (TES) tank and solar collector is studied for their application in solar concentrated power (CSP) plant. The TES tank uses packed-bed ore as heat storage material. Both experimental and numeric methods are conducted to build its theoretical model, which is used in the simulation of the whole CSP system. The theoretical model of the CSP system mainly composes of three parts: solar radiation, solar collector, and TES tank. It is simulated in the location of city Nanjing, China, to study its dynamic performance in the corresponding solar radiation environment in 4 seasons. The result of simulation shows that the CSP system with TES has stable performance while the solar radiation input varies with hour and season. According to the local solar environmental parameters, (the solar radiation energy density within one day of about 28 MJ/m2, and daytime of about 12 h), the solar system with solar collector and thermocline TES tank of proper capacity is designed. In the absence of sunshine during night, the system could supply heat of 225 kW for 12 h continuously, with an efficiency around 51%. With the similar research methods, it is feasible to assess the performance of thermocline TES single tank in CSP system.