Review of photovoltaic cooling methods to improve electrical efficiency

Photovoltaic (PV) modules experience substantial electrical efficiency losses under elevated operating temperatures, driving increasing interest in active and passive cooling strategies. This review synthesizes the state of the art in PV cooling methods, categorizing them into passive techniques (heat sinks, fins, phase change materials, radiative coatings, and natural convection enhancements) and active approaches (air cooling, liquid cooling, jet impingement, sprays, and hybrid PVT systems). For each method, underlying thermal mechanisms, reported temperature reductions, and corresponding electrical performance gains are compared. The review highlights that active liquid-based cooling and hybrid PV-thermal configurations generally achieve the highest heat extraction rates but face challenges in pumping power, system complexity, and economic viability. In contrast, passive solutions offer lower maintenance and energy overhead but provide modest cooling effects and limited controllability. Emerging concepts, including nanofluids, spectral-selective surfaces, microchannel devices, and PCM-integrated designs, show promise but require further validation for durability, scalability, and outdoor deployment. Environmental and techno-economic considerations, including water use, lifecycle impacts, and cost–benefit factors, are also examined. The review concludes by identifying performance benchmarks, research gaps, and pathways for advancing deployment-ready PV cooling technologies that can reliably improve electrical efficiency under real-world conditions.