Experimental study in a compound parabolic solar concentrator with different configurations of thermal energy storage system

This study explores the integration of thermal energy storage (TES) systems with solar water heating systems to increase their utilization time. While solar water heating systems are effective for low-temperature applications, they become less efficient at higher heat transfer fluid (HTF) temperatures. To solve this problem, the study suggests combining a compound parabolic concentrator (CPC) solar collector with a TES system to improve heat transfer rates and minimize heat loss. The study examines the effect of different mass flow rates and HTF inlet temperatures on the integrated system's performance, evaluating energy efficiency, exergy efficiency, and overall loss coefficient. The results reveal that the six-phase change materials (PCMs) configuration achieves the highest intercept line efficiency of 72%, with a heat transfer rate 1.7 times higher than that of the single PCM configuration. Moreover, the exergy analysis shows superior performance compared to commonly used flat collectors. Overall, the proposed CPC solar collector integrated with a TES system is suitable for low-temperature applications with an inlet HTF temperature not exceeding 65 degrees C.