Autonomous Evaporative Cooling of Solar Photovoltaics Panels Achieved by a Bio‐Inspired Fog‐Harvesting Composite for Arid Regions

ABSTRACT

Solar photovoltaics (PV) are pivotal in the global shift toward sustainable energy, especially in sun‐drenched arid regions. Nevertheless, PV panel efficiency and lifespan are compromised by overheating from intense solar irradiation. Although evaporative cooling is an attractive passive approach due to energy‐saving and maintenance‐free traits, conventional hygroscopic materials perform poorly in arid climates due to dependence on ambient humidity. Inspired by the fog‐harvesting adaptation of the Namib Desert beetle, this work presents an integrated, self‐sustaining cooling system that operates independently of external water. The design includes two synergistic components: a biomimetic fog collector with a hydrophilic–hydrophobic patterned surface (CuO@PTFE mesh) for atmospheric water capture, and a temperature‐sensitive hydrogel loaded with LiCl crystals for on‐demand water storage and thermally regulated release. In lab simulations of a desert environment, the system achieved a peak temperature reduction of 20.4°C and a consistent power output improvement of 7.58%. Subsequent ten‐day field tests in arid zones of China—Turpan, Ordos, and Chifeng—confirmed operational reliability, with an average daytime temperature drop over 8.0°C. This bio‐inspired autonomous configuration offers a viable and sustainable route to boosting energy generation and prolonging the service life of PV installations in water‐scarce regions.