Numerical analysis of photovoltaic solar panel cooling by a flat plate closed-loop pulsating heat pipe

Photovoltaic (PV) panels provide a suitable way for the direct conversion of solar energy into electricity. The electrical output and efficiency of PV modules are dependent on working temperature. The present study contributes to investigate the efficiency of utilizing a flat plate closed-loop pulsating heat pipe (CLPHP) to cool down a PV panel in both thermal and economic aspects. Accordingly, a numerical investigation is employed to obtain the surface temperature and electrical gain of the PV panel through four scenarios, including natural cooling without additional equipment, CLPHP-based passive cooling, CLPHP-based active cooling, and a conventional flat plate cooling methods. The efficiency of the cooling approaches is investigated in three different solar radiations and ambient temperatures according to the climatic condition of the considered location, Kerman, Iran. The improvement rate function is established to elaborate on the electrical gain efficiency of each scenario. Furthermore, each scenario is economically compared in terms of the payback period of the different cooling approaches. It is concluded that applying CLPHP-based passive, and active cooling approaches increase the improvement rate by 23% and 35% at the solar radiation of 1235 W/m(2), respectively. In addition, the results demonstrated that while the 4th scenario, conventional approach, induces higher improvement rate, it requires more operational cost, so increases the payback period by about 10% compared to the 3rd scenario. Accordingly, it is concluded that utilizing CLPHP for cooling the PV panel is an appropriate and cost-effective approach to increase the efficiency of the PV panel.