Experimental investigation of using the evaporative air cooling technique to enhance the performance of the photovoltaic module

Abstract In this experimental study, two techniques of photovoltaic thermal (PVT) collector with active cooling were used to enhance the performance of the photovoltaic (PV) module. The first technique was prepared by integrating the PV module with a forced air duct (PVTFC). At the same time, the second technique was the PV module integrated with a forced air duct including a direct evaporative cooling unit (PVTDEC). In these two techniques, the air was forced by an electrical centrifugal fan with variable speeds (1.5, 2.5 and 3.5 m/s) placed at the end of the duct. The output electrical characteristics of the PVTFC and PVTDEC modules were compared with the reference PV module. The obtained results showed a significant decrease in the temperature of the PV module, where the reduction in the temperature of the PV module was achieved between 5°C and 16°C and 21°C and 25°C in PVTFC and PVTDEC techniques, respectively. Accordingly, the voltage was dropped to 15.1 and 15.8 V in PVTFC and PVTDEC, respectively, as compared with the sharp decline of voltage for the reference PV module, which recorded 14.2 V at a maximum PV module temperature of 69°C. In addition, the maximum enhancement percentage of PV efficiency was achieved at a maximum airflow rate of 0.22 kg/s, where it was recorded between 3.5% and 6.2% in the case of PVTFC and 7% and 9.3% in the case of PVTDEC.