Simulation and performance analysis of solar adsorption cooling systems

This study investigates the technical and economic feasibility of solar-powered adsorption cooling systems in Saudi Arabia, a region with high solar irradiance and growing energy demands for cooling. Given Saudi Arabia's reliance on energy-intensive cooling and its abundant solar resources, this study hypothesizes that solar adsorption systems can offer a sustainable solution to alleviate electricity demand for cooling in regions with rising energy needs. Using Polysun® 5.9 simulation software and real-world climate data from four major cities including Riyadh, Jeddah, Dammam, and Abha for the performance of two adsorption chillers, silica gel-water (ACS15) and zeolite-water (HTC11), was evaluated. The simulations reveal that a system utilizing 45 m² flat-plate solar collectors and an 8 m³ hot water storage tank can effectively reduce grid electricity consumption by up to 16,000 kWh annually, depending on the configuration and recooler type. The study highlights the superior performance of wet recoolers, particularly in arid climates like Riyadh, where the thermal coefficient of performance (COP th ) increases from 0.35 to 0.43, while the electrical coefficient of performance (COP el ) nearly doubles compared to dry recoolers. Economically, the system yields annual electricity savings of up to $1280, with a payback period of 22–26 years, which could be reduced to 15–18 years with government subsidies. Furthermore, the system contributes to sustainability by saving up to 9.41 barrels of oil equivalent annually. These findings demonstrate that solar-powered adsorption cooling systems offer a viable, energy-efficient, and environmentally friendly alternative to conventional vapor compression systems, especially in regions with abundant solar energy. Despite its technical promise, adsorption cooling remains limited in implementation due to high initial capital costs, complex system integration challenges, and relatively lower performance under extreme climatic conditions compared to conventional systems. However, the high initial investment costs require further reduction through technological improvements and government support to encourage broader adoption.