Bio-inspired fractal vein-like structure coupled with hygroscopic hydrogel for high-efficient thermal management of photovoltaic systems

Amidst the growing global emphasis on energy conservation, environmental protection, and climate change mitigation, solar photovoltaic panels have garnered widespread recognition as a sustainable energy solution. However, prolonged exposure to sunlight inevitably raises the temperature of photovoltaic panels, resulting in a reduction in their efficiency and service life. To tackle these challenges, there is a pressing need to develop advanced photovoltaic thermal management technologies. This article introduces a novel bio-inspired fractal vein-like structure integrated with hygroscopic salts for efficient thermal management of photovoltaic (PV) systems. By incorporating hygroscopic salts into the hydrogel, a cyclic process of water molecule adsorption and desorption is realized by mimicking sweat cooling. The 3D-printed aluminum alloy bio-inspired leaf vein serves as heat transfer skeleton, fast transferring the heat to the hydrogel with large enthalpy, effectively reduces the temperature of the photovoltaic cell and enhances its photoelectric conversion efficiency. Experimental results demonstrate that this thermal management system could reduce the maximum temperature of the photovoltaic cell surface by 18.41 °C under laboratory conditions and by 9.02 °C in outdoor applications, increasing the maximum output power by 38.09 %. This thermal management strategy offers a reliable, efficient, and environmentally friendly solution for the photovoltaic cells cooling.