PV power stations are installed outdoors. Under strong summer sunlight, the metal roofs, cable trays, and supporting components beneath the PV panels accumulate heat rapidly, forming a high-temperature thermal field that bakes the backsheets of PV modules from below. PV modules have a high-temperature derating characteristic: the higher the ambient temperature, the lower the photoelectric conversion efficiency. High temperatures also accelerate aging of cables on the trays, backsheets, and inverters, increasing station O&M costs and risks of failure and self-ignition. The electricity-free cooling coating requires no coating on PV glass panels; it acts only on the supporting metal structures of the power station, providing passive, power-free cooling, reducing bottom thermal radiation, optimizing module operating temperature, improving generation efficiency, and extending equipment service life.