A Solar Assisted Spherical Capsule-type Latent Heat Thermal Energy Storage/heat Pump System

A unique latent heat thermal energy storage/heat pump(LHTES/HP) system using spherical capsules was proposed, and the experimental and the simulated results were presented when this system is operated as a solar system. In this paper, it shown that the supercooling of the phase change material(PCM), which has been one of the most serious problem in using many salt hydrates, can be resolved by introduction of a heat pump, since the stored heat during the supercooling period can be utilized through the aid of the heat pump. Furthermore, the variation of the coefficient of performance(COP) of the heat pump, the effects of the flow rate of the working fluid, the collector area, the ambient temperature, the capsule diameter, etc. on the thermal performance are examined via the prototype experiments and the computer simulation.