Energy, freshwater, and the environment are interrelated factors that permeate all our activities on the earth. They have become the most important and popular topics in research fields nowadays. This paper studies improving the performance of the adsorption desalination system by improving a commercial silica gel as an adsorbent. Acid treatment has been used to activation for the silica gel. Then, a composite adsorbent is prepared chemically using silica gel as a host matrix and impregnated in CaCl₂ salt hydrate. Water vapor adsorption isotherm and kinetics are investigated for raw, treated, and composite silica gel. The Dubinin-Astakhov (D-A) and linear driving force models (LDF) have fitted experimental isotherm and kinetic results. The system is driven by renewable energy such as solar energy. The results illustrated that the silica gel/CaCl₂ achieved water uptake (0.95 kg_H2O/kg). It is also observed that the composite silica gel based-adsorption desalination cycle provides specific daily water production of 70 % higher than the raw silica gel-based adsorption desalination cycle.