Thermal regulation of photovoltaics using various nano-enhanced phase change materials: An experimental study

Abstract

Photovoltaics thermal (PV/T) management has attracted much attention in research, with a particular focus on improving its performance in the current globalized market. As the continuous elevation of PV surface temperature due to direct sun rays degrades PV/T performance, effective cooling of PV panels has been identified as a way of improving efficiency. Thermal regulation strategies have suggested that water, nanofluids, air, phase change materials (PCM), and nano-enhanced PCMs can be varied for cooling purposes. The current study considers silica and carbon black nanoparticles dispersed in phase change materials for two purposes: firstly, to increase the speed of storing and releasing thermal energy of nano-enhanced PCM; and secondly, for improving the thermal conductivity of PCM. The experimentation of this study was conducted in outdoor conditions of Taxila, Pakistan during the month of March 2020. To construct the nano-enhanced PCM, Silica (SiO2) and Carbon Black (CB) NPs were added to PT-58 at concentrations of 0.25 wt % and 0.5 wt %. NPs at 0.5 wt % concentration in CB/PT-58 as a nano-enhanced PCM showed the topmost performance in cooling of a PV panel. The experimentation depicted a maximum decrease in temperature of the system using CB/PT-58 and SiO2/PT-58, at approximately 9.74 °C and 8.92 °C respectively, where the electrical efficiency of the systems improved to 12.07% and 12.00% respectively, at a concentration of 0.5 wt %. The maximum percentage increment in electrical power was 30.45 % and 30.23 % respectively, in the case of CB/PT-58 and silica/PT-58 nano-PCM at 0.5 wt % of NPs in base PCM. The results elucidate that the performance of the system using the CB/PT-58 nano-PCM as a cooling method was higher than the silica/PT-58 nano-PCM.