Application of solar driven two-stage desiccant cooling/heating system

A solar driven two-stage desiccant cooling/heating system has been installed and operated for the Electronic Workplace at Himin Solar in China. It consists primarily of a 20kW desiccant cooling system and 120m² of solar air collectors. The outlet temperature of solar air collectors is about 60-100 °C and the thermal efficiency can reach to 50%. In addition, the effect of connection modes on the performance of solar air collectors is studied using the thermal efficiency. Solar desiccant system can realize cooling in summer and heating in winter. For the solar driven two-stage desiccant cooling system, the moisture removal can reach 9-12g/kg and supply air condition is about 16 °C and 60% RH. Experimental results indicated that the average thermal COP in cooling cycle is 0.97 and the cooling capacity is in the range of 16.3-25.6 kW in hot and humid climate conditions. Comparing with direct heating, heating with humidification can reach more comfort state. The solar COP of system is about 0.45 when thermal efficiency of collector is 50%. This suggested that the system could convert more than 40% of the received solar radiant intensity to cooling power in sunny days.