Abstract: To further improve the cooling power generation performance of photovoltaic panels, the porous vermiculite was selected as carriers of CaCl2salt and water, and the effects of three cooling methods namely moisture absorption/desorption, water storage evaporation, intermittent spray, on the upper and lower surface temperatures and power generation performance of photovoltaic panels were investigated in this paper. It is found that porous vermiculite carried CaCl2salt can increase photovoltaic power generation, but its cooling effect is limited due to lower evaporation moisture content and large thermal resistance for heat dissipation of photovoltaic panel back. The water storage evaporation of porous vermiculite can effectively reduce the temperature of photovoltaic panels; once water storage in a day can meet the water evaporation demand for a day; the power generation efficiency can increase by 2.5% compared with that of photovoltaic panels without cooling. The combination of intermittent spray and water storage in porous vermiculite can further increase the power generation efficiency up to 8.2%, compared with the evaporation cooling of water storage in porous vermiculite.