Efficiency enhancement of PV panels with passive thermal management using PCM: An exhaustive review on materials, designs and effective techniques

Maximizing power production in photovoltaic (PV) technology is a key strategy in the energy transition paradigm. Therefore, it is essential to consider the potential factors that influence PV efficiency. One of the primary factors is solar irradiation which is inherently variable and beyond human control. While higher irradiation levels can boost PV power output to some extent, they also lead to higher operating temperatures, which can negatively impact the efficiency of the PV panel. As a result, passive cooling emerges as a key solution to mitigate the efficiency drop caused by rising operating temperatures. This study aims to provide a comprehensive review of phase change materials (PCMs)-based passive cooling techniques, which hold significant potential for enhancing the efficiency of PV panels. The review begins by characterizing the ideal phase change material (PCM) and identifying various PCMs, along with their thermophysical properties, that have potential applications in PV panel cooling. An in-depth investigation is then conducted on several PV-PCM research studies, focusing on key aspects such as the design parameters of PCM containers and PV capacity, variations in PCM mediums, the impact of environmental conditions, and the integration of other passive cooling approaches with the PV-PCM system. This review is conducted by exploring the impact of various influencing factors on heat transfer modes, such as convection and conduction, and their effects on the performance of the PV-PCM system. To further improve the thermal performance of PCMs, a holistic overview of approaches to enhancing their thermophysical properties is provided. This includes the integration of PCMs with extended surfaces, heat pipes, and metal and non-metal foams. Additionally, the review explores the potential of doping PCMs with high thermal conductivity materials and discusses the benefits of PCM encapsulation. Based on key observations derived from experimental and simulation studies of PV-PCM research and thermal performance enhancement, a conceptual framework for selecting suitable PCMs for PV cooling applications is proposed. Furthermore, the review extends its contribution by offering research directions, suggestions, and design recommendations to guide prospective studies in PV-PCM systems.