This paper is one of the first to propose seawater for cooling PV panels. It presents and describes a novel experimental investigation for cooling solar panels using saturated activated alumina with saline water. Six different water salinities of (0, 5, 10, 35, 80, and 337) particles per thousands (PPT) saltwater were used at different radiation intensities. Additionally, new internal and external configuration of materials’ containers are suggested. Two radiation intensities of 800 W/m2 and 1000 W/m2 were selected and applied for the complete test period of 6 h. Experiments were repeated for a periodic cycle of four months to monitor the salt effect on the activated alumina tablets; This was done by using an optical microscope to look at the microscopical state. Results showed that saturated activated alumina tablets with saline water gives the same cooling performance as using pure water. At salinities higher than 35 PPT …