Experimental investigation of solar driven desiccant air conditioning system based on silica gel coated heat exchanger

• A silica gel coated heat exchanger based solar powered desiccant cooling/heating system has been proposed.
• The pre-cooling and post-cooling are advantageous to the performance of the system.
• The system was not able to attain the comfort conditions.

A silica gel coated heat exchanger based air conditioning system driven by the evacuated tube solar water heater has been experimentally investigated. The system has been operated for two different modes namely cooling with dehumidification mode and heating with humidification mode in summer and winter season respectively. The system performance is analyzed in terms of regeneration rate, dehumidification rate and thermal coefficient of performance (COPth). Experimental results demonstrated that, for cooling and dehumidification mode, the process air is cooled by an average temperature of 8.5 °C. A better dehumidification rate can be achieved by using pre-cooling before dehumidification process. Post-cooling after dehumidification process is found to be advantageous for cooling capacity and COPth. For heating with humidification mode, the process air is heated by an average temperature of 13.3 °C with an average increment in humidity ratio of 1.9 g/kg. It is found that the average COPth of the system is 0.45 and 0.87 for cooling and heating mode respectively.