Experimental investigation of a solar adsorption chiller used for grain depot cooling

The solar cooling technology is attractive since cooling load of building is roughly in phase with solar energy availability. In this study, a solar adsorption chiller was built and tested with aim of developing an alternative refrigeration system used for grain cooling storage. This solar adsorption chiller consists of four subsystems, namely, a solar water heating unit with 49.4 m2 solar collecting area, a silica gel–water adsorption chiller, a cooling tower and a fan coil unit. In order to achieve continuous refrigeration, two adsorption units are operated out-of-phase with mass recovery cycle in the adsorption chiller. Field test results show that, under the climatic conditions of daily solar radiation being about 16–21 MJ/m2, this solar adsorption chiller can furnish 14–22 °C chilled air with an average cooling output ranging from about 3.2–4.4 kW, its daily solar cooling COP (coefficient of performance) is about 0.1–0.13.