Experimental Evaluation of Energy Conversion Characteristics in Composite Photovoltaic/Thermal System with Phase Change Material

The output power of photovoltaic modules (PV) is easily affected by high temperature. To address this issue, a PV/T-PCM composite system integrating phase change material (PCM), metal fins, and heat exchange tubes was proposed, designed, and tested. The performance of four photovoltaic cooling systems, namely PV, PV/T, PV-PCM, and PV/T-PCM, was compared and studied. The results indicate that the average temperature of the PV/T and PV-PCM systems dropped by 8.49 °C and 11.65 °C, respectively, in comparison to the reference PV system, and the output power rose by 12.77% and 14.45%, respectively. Additionally, the heat storage in the PV-PCM system was 8446.49 kJ. However, both the PV/T and PV-PCM systems endure overheating under long-term operation. The average temperature of the PV module of the PV/T-PCM system is 44.96 °C, which is 14.49 °C lower than that of the PV system, and the peak temperature is delayed by 72 min. The average daily output power of the PV/T-PCM system is 386.77 Wh, which is 35.54% higher than that of the PV system, and the total heat storage capacity is 14494 kJ. Compared with the PV-PCM system, its thermal storage efficiency is increased by 71.6%.