Photovoltaic cooling systems review integrating technical, economic, and environmental dimensions encompassing life cycle assessment

Abstract

The switch to renewable energies is of key importance for both reducing global CO₂ emissions and offering long-term energy security. In both regards, photovoltaic systems occupy the central position in this paradigm shift. However, heating usually reduces the efficiency of a photovoltaic system hence making cooling measures paramount. This paper reviews the recent developments in cooling techniques used with solar panels within the last five years, necessarily focused on economic and environmental studies included in an entire life cycle assessment (LCA). The cooling techniques have been reviewed: air-based, liquid-based, phase-change material (PCM), radiative sky cooling, thermoelectric generators, Peltier effect evaporative cooling, and hybrid systems. This article, unlike prior studies, investigates all known studies, integrating the life cycle approach. It goes beyond benefits in thermal performance to consider the economic and environmental implications of each cooling strategy. For instance, the combined thermoelectric generators with PCM increased electrical power generation by 20 to 30 % in sunny conditions. A more interesting development is that hybrid techniques using PCM in conjunction with water-cooling techniques, have achieved an overall improvement of 22.8 % in electrical efficiency. The evaporative cooling systems had the potential to drop temperature by 22.7 % and increase the generated output power by 16.3 W for a polycrystalline 50 W module in a dry region. The nanofluid cooling techniques decreased the PV surface temperature by 23.14 %, increasing their efficiency to 20.2 %. However, there still significant gaps in thorough economic, environmental, and LCA assessments necessitating further investigation into feasibility and long-term impacts of cooling systems.