Abstract

This work investigates the use of phase change materials (PCMs) as a passive cooling system to increase the electric power generation of photovoltaic panels (PV) by a reduction of the temperature of the panels. This study aims to evaluate different configurations of PV-PCM cooling systems, by changing the phase change material, to achieve a high efficiency in a silicon PV. Each configuration is studied for three day-night cycles under seasonal variable atmospheric conditions. Two Chilean cities with a semi-arid climate and arid climate - Vicuna and Calama, respectively - were selected as the study locations. The development of the PV-PCM improved system is carried out by solving the unsteady thermal energy equation with computational simulations using the finite volume method (FVM). An Enhanced Conduction Model (ECM) was used to include the convective heat transfer in the melted PCM. The ECM was validated against numerical values of a PV-PCM system finding a maximum deviation for the PV frontal temperature of 1.23 degrees C. The numerical model was validated with experimental and numerical results of a PV-PCM system during a 24-hour cycle with time -varying atmospheric conditions. The results obtained indicate that the use of phase change materials as a cooling system decreases up to 17.5 degrees C the temperature at the PV, diminishing the losses of efficiency and increasing the generation of electricity. The electrical production in one year increases by 5.8% for Vicuna and 4.5% for Calama when a layer of CaCl2-6H2O with a thickness of 40 mm is used.