Simultaneous use of porous medium and phase change material as coolant of photovoltaic modules; thermodynamic analysis

摘要

Conversion of light into electricity is possible by means of photovoltaic (PV) technology. The negative impact of increasing the temperature of PV cells on their output power is one of the most important weaknesses of this technology. In this experimental study, a porous medium integrated with phase change material (PCM) as two passive cooling methods of PV modules are employed and their effects on cooling the PV panel are investigated, either separately or simultaneously. Two thickness values of the aluminum porous medium were mounted at the back side of PV module. The results show that a 2 cm thick porous medium reduces the module temperature by 14.5 degrees C, while when PCM is added, the temperature drop reaches 21.5 degrees C compared to a conventional PV module. Moreover, adding PCM, downgrades the rate of temperature rise. Increasing the output power due to the use of PCM and porous media, causes 18.6 less PV modules to run a 10-kW photovoltaic power plant. The entropy generation of the system was also calculated and 4 difference between the mentioned cases was calculated. An important concern about the thermal exergy assessment is discussed in details.