Performance investigation of a solar cascade liquid desiccant regeneration system for hot and humid climates

A new solar cascade regeneration system was developed with the goal of producing a reliable and energy-efficient liquid desiccant regeneration process. This process is specifically designed for liquid desiccant air-conditioning systems in severely hot and humid climates. The regeneration characteristic of this new system is researched and compared with the conventional hollow fiber membrane thermal regeneration system. Results show that the increase of desiccant concentration difference between regenerate and dilute solutions in electrodialysis regenerator will decrease the required heating temperature and energy consumption of the new system, which means the new system can conveniently control the required heating temperature to meet the variable environment condition. With the same environment condition, the new system has lower required heating temperature and energy consumption than the conventional hollow fiber membrane thermal regeneration system. Among all simulation conditions, compared with the conventional hollow fiber membrane thermal regeneration system, the largest heating temperature drop of 7 degrees C and the highest energy-saving of 14% can be achieved when the new system is applied. It can be concluded that the new solar cascade regeneration system can work stably and reliably under the severe hot and humid climate as its low heating temperature requirement and energy-saving potential.