An experimental observations of an air-tight thermal storage tank in particle-based concentrated solar power systems

During commissioning of the CSP test facility at King Saud University, a large temperature drop was noted when charging the thermal energy storage (TES) bin. Heat loss can be mitigated by using an airtight TES bin. In this paper, we present a small-scale TES bin, which can be isolated and sealed from its surroundings, i.e., the TES bin can be confined, isolated and sealed from its environment. There were two operational scenarios simulated, namely the start-up and steady-state scenarios. In the start-up scenario, the bin’s centerline temperature was almost the same as the particle inlet temperature. Thus, the bin’s wall was the sole cause of heat loss. Entrained air did not contribute to heat loss. Based on the results of the steady-state scenario, an air-tight bin can reduce the charging/discharging loss sufficiently. Additionally, no "significant" build-up of pressure was detected during bin charging.