The integration of heat pipe technology into photovoltaic panels to increase the operational efficiency

Abstract

The Sultanate of Oman growth in population and infrastructure expansion in recent years resulted in increased energy consumption. As a solution to meet the increasing energy demand, energy management strategies and renewable energy-driven technologies are the most viable alternatives. Among these technologies solar photovoltaics (PV) are the most promising technology due to the strong support from the Omani government. This study introduces a Heat Pipe Heat Exchanger (HPHE) technology as a passive cooling mechanism to be integrated within PV terminals. The aim of this research is to increase the energy capacity of rooftop PV modules in hot and arid climates like the Sultanate of Oman. The performance of the existing grid photovoltaic system was benchmarked using a thermal collector and data loggers which monitored the PV modules temperature. The experimental investigation resulted in the establishment of the site solar irradiation of 911.11 ± 143.43 W/m2 and the Nominal Operating Cell Temperature (NOCT) of 61.4 ℃ which produced the Peak PV Power efficiency of 54.8 %. The recorded findings of 63.8 ℃ in the NOCT had reduced the PV Power efficiency by 2.19%. The Computational Fluid Dynamics (CFD) modelling of the HPHE using a single independent PV panel and its analysis was made using different methodology of investigation to specify the optimum configuration. The CFD modelling results were used to identify that the efficient physical set up is made of PV-HPHE-DSCD (Double Sided Condenser) orientation with screen mesh wick. The optimum configuration was made of 20 units HPHE arranged on 50 mm on centers at an angle of inclination of 3 degree in the middle installation of the PV back surface. Water was used as a refrigerant with a fill ratio of 65% which equates to 59 ml loaded into the evaporator section. The results of the final stage of the experimental set up had an average PV-HPHE power performance of 29.03 ± 0.047 % and an average power generation of 71.94 ± 2.41 W that comprised of 23.98 % of the rated PV power capacity. The validation of the CFD model using experimental testing was carried out by determining the error which was found to be within the accepted range with a mass flow rate of 2.07e-05 kg/s equivalent to an average flow rate of 8.13 e-05 m/s (Al-Mabsali et al., 2021) in the evaporator to condenser flow direction. The significance of the research data indicates that if the heat pipe technology is incorporated in typical outdoor conditions and the power efficiency of the device can be improved to a maximum of 7.94% from an average power efficiency of 5.09%.