Enhancing Solar Photovoltaic System Efficiency: Recent Progress on Its Cooling Techniques

Abstract

There is a paradox involved in the operation of photovoltaic (PV) systems; although sunlight is critical for PV systems to produce electricity, it also elevates the operating temperature of the panels. This excess heat reduces both the lifespan and efficiency of the system. The temperature rise of the PV system can be curbed by the implementation of various cooling strategies. These strategies fall under three categories: passive, active, and hybrid cooling, with similar objectives of regulating excess heat generation. Employing heat pipes can be an example of the passive method, while the use of forced circulation of water flow can represent an active method. A combination of energy storage and forced convection represents an example of hybrid cooling. Most of the research has two objectives, one to obtain higher PV efficiency and another to enhance the life span of the system. This review explores various cooling strategies employed by the researchers i.e., heat pipes, heat sink, air or water channels, water spray, use of phase change material, microchannel for coolant passage, thermoelectric (Peltier) modules. In general, for passive cooling techniques, efficiency enhancement of up to 44.12 % was obtained due to the temperature reduction of around 11 °C. In the case of active cooling techniques reported better performance with PV temperature reduction as high as 55 °C. Hybrid cooling also leads to some promising performance improvements. Characteristics and performance of various cooling methods are explained in this review to provide future researchers with valuable insight and direction. This could lead to much better improvements in these cooling techniques in the near future.