Photovoltaic panel cooling with new composite of phase change materials and hierarchical nanoparticles

In this research, the use of a new type of phase change materials (PCM) and hierarchical nanoparticles is discussed to improve the electrical and thermal efficiency of PV panels. TiO2/CuO hierarchical nanoparticles are synthesized by hydrothermal method, and PCMs containing nanoparticles (2.5–10%wt) are prepared, and then experiments are performed in indoor conditions under solar simulator light. The PV panel with a maximum nominal power of 30W is used. The new PCM is made from a mixture of lauryl alcohol and beeswax (LABW). A spiral heat exchanger is placed in the PCM container, in which the flow rate of cool water is variable (m˙ = 0.002–0.01 kg s−1). Firstly, the temperature and voltage-current changes of the PV panel with time are investigated without using PCMs as a reference case, and in steady-state conditions, the temperature and output power values are 67.34 °C and 22.33W. The use of LABW compared to pure beeswax leads to a significant decrease in the PV panel temperature and as a result, an increase in its electrical and thermal efficiency. Also, adding nanoparticles to PCMs from 2.5 % to 7.5 %wt due to the improvement of their thermal conductivity and increasing the heat storage rate of the PV panel leads to an increase in its electrical and thermal efficiency. There is no significant change to decrease the temperature and increase the production capacity of PV panels by increasing the percentage of nanoparticles from 7.5 % to 10%wt. The maximum production power, electrical and thermal efficiency of the PV panel at a flow rate of 0.01 kg s−1, 10%wt of nanoparticles, and a radiation intensity of 1000 W m−2 are 28.92 W, 12.55 %, and 76.67 %, respectively.