Effect of excess-heat recycling on the performance of solar regenerator

Requirement of energy has caused the great progresses of research on solar energy. As an important branch, solar desiccant cooling system has many advantages, but it could not be used widely as a mature technology because of some obstacles. This paper released that the regenerator in the system was usually less effective than expected. In order to enhance the performance, an air-air heat exchanger (AAHE) as excess-heat recycling device was installed in the regenerator to capture excess heat of hot-air. Two prototypes of regenerator were developed, regenerator installed with AAHE (WAAHE) and not installed with AAHE (NAAHE). The performance of two regenerators was measured, tested and evaluated. The results showed that dehumidification increments and regeneration efficiencies of regenerator both increased with the growth of water temperature. Dehumidification increment of WAAHE could be 40-55g/kg, which was more 30g/kg than that of NAAHE. The regeneration efficiency of WAAHE could reach 50-60% at 90°C of hot water, which was 30-50% higher than that of NAAHE. So the key performance of regenerator was effectively improved by the addition of air-air heat exchanger. It can be concluded that the addition of air-air heat exchanger to the solar regenerator could utilize solar energy effectively and improve the regeneration efficiency. It implied that excess-heat recycling was necessary for solar regenerator.