Enhancing the efficiency of solar photovoltaic systems via smart cooling in arid environments

Abstract

Arid regions offer significant potential for photovoltaic (PV) energy generation due to their consistently high solar irradiance. However, the elevated operating temperatures common in such environments substantially reduce electrical efficiency and accelerate module degradation. This study presents an experimental investigation of a novel water-spray cooling system for active front-surface cooling of PV panels, with an emphasis on optimizing both thermal dissipation and water consumption. The system consists of a top-mounted manifold with fine nozzles, powered by a pump and controlled by an Arduino-based unit that activates spraying only when module temperature exceeds a predefined threshold—an approach termed “smart cooling”. A comparative outdoor experiment was conducted in Ouargla, Algeria, from June 9 to July 4, 2024, using two identical 390 W monocrystalline silicon panels: one equipped with the cooling system and one serving as an uncooled reference. Under peak irradiance (979 W/m2) and an ambient temperature of 40.4 °C, the cooled panel generated 350.5 W, compared with 272.1 W from the reference panel. This corresponds to a maximum efficiency gain of 28.8%, achieved as the surface temperature dropped from 58.6 °C to 36.7 °C. Continuous cooling improved average efficiency by 15.4%, whereas smart cooling delivered a comparable 15.5% improvement while using 84% less water. Additionally, the periodic spraying helped mitigate dust accumulation on the panel surface. An economic analysis revealed that smart cooling lowers the annual levelized cost of power production to 0.07020 €/W, compared with 0.07514 €/W for continuous cooling and 0.07135 €/W for an uncooled module. These results demonstrate that adaptive water spraying can effectively enhance PV performance in arid climates while significantly conserving water resources.