Experimental study on passive cooling of photovoltaic panel by harvesting atmospheric water using hygroscopic salt

The electrical performance of solar photovoltaic panel can be enhanced by reducing its operating temperature at daytime. An experimental investigation is carried out in the local region where humidity is very high with relative humidity of about 90 %. A passive cooling system with CaCl 2 hygroscopic salt with additive is considered. The salt compound facilitates water supply for panel cooling by convection and evaporative cooling method. The performance of panel with desorption cooling method is compared against the panel without any cooling. Further, the study is extended to find the influence of additive and its weight percentage on power output of solar panels. The observation revealed that the panel temperature reduced about 3.1 % thus increased power output by 17.38 %. From the experimentation, it is concluded that reducing the temperature not results into increased power output always because some shortcomings in cooling method affects solar irradiation. The sedimentation of salt reduces solar irradiation and cleaning of panel surface becomes mandatory.