Solar Photovoltaics Integrated With Hydrated Salt-Based Phase Change Material

Abstract

Maintaining the temperature of the photovoltaic (PV) panel within the described standard helps in achieving higher power conversion efficiency. To regulate the PV temperature, phase change material (PCM)-based cooling techniques have been proposed in several literature. However, most of the studies utilize organic PCMs whose low thermal conductivity confines their potential. Thus, in the proposed work, the rear side of the 20 Wp PV panel is coated with hydrated salt-based PCM and is integrated with an aluminum sheet (PV–PCM–Al) to increase the thermal conductivity of the system. The effect of the PV–PCM–Al panel in enhancing the PV efficiency is realized by comparing it with a standard uncooled PV panel. This concept was experimented under direct sunlight for about a week in Chennai, the southern part of India. To perceive the performance enhancement, thermal images were taken for both the cooled and uncooled PV panels. In addition, open-circuit voltage, short-circuit current, and power output were measured. The experimentation is also backed up by numerical simulations to understand the heat transfer characteristic features of the designed integrated PCM and aluminum cooling system. The experimentation results highlight that a maximum increase of about 7.67% in the PV efficiency was obtained using a cooled PV panel when compared to an uncooled PV panel. A maximum increase of 7.34% in the open-circuit voltage and a maximum drop of 4.6 °C in the PV temperature were obtained.