The Effect of SiO2 Nanoparticle on the Performance of Photovoltaic Thermal System: Experimental and Theoretical Approach

The low conversion efficiency of solar cells produces large amounts of thermal energy to the cells, and with an increase in the temperature of solar cells, their electrical efficiency decreases. Therefore, a hybrid photovoltaic thermal (PVT) system ameliorates the total performance of the system by adding thermo equipment to the solar cell and removing excessive heat from these cells. In this paper, we inspect SiO2/water nanofluids effect on the electrical and thermal efficiency of domestic photovoltaic thermal systems (DPVT) theoretically and experimentally. In the theoretical part, as a result of the control-volume finite-difference (CVFD) method, an explicit dynamic model was extended for a flat-plate collector, which is added to the photovoltaic panel with a closed-loop cooling system with withdrawing urban water from the storage tank. The model accuracy was verified in comparison with the measured experimental data. Experimental results indicate that by increasing the concentrations of nanofluid, the thermal and electrical performance has improved, and overall efficiency decreased by increasing the diameter of the nanoparticles. The overall efficiency of the DPVT for 0 and 3 weight percent of SiO2/ water nanofluids with a diameter of 11-14 nanometers enhanced to 5.4% and 7.76% compared to the base fluid, respectively.