Optimal design, sizing and operation of heat-pump liquid desiccant air conditioning systems

Heat-pump liquid desiccant air conditioning (heat-pump LDAC) systems can provide effective control over indoor air humidity and provide healthy environments for occupants. Although several studies have been recently conducted on heat-pump LDAC systems, no information is available in the scientific literature about how to design, size, and operate these systems to optimize energy efficiency. A novel thermodynamic analysis for heat-pump LDAC systems is developed and presented in this paper. The thermodynamic analysis is aimed to guide engineers and researchers to identify optimal operating points for the design, sizing, and operation of heat-pump LDAC systems. This thermodynamic analysis reveals a new fundamental capacity matching index for heat-pump LDAC systems that optimizes energy efficiency (increasing COP by 50%). The proposed thermodynamic analysis is demonstrated in this study on a heat-pump membrane LDAC system, which uses two liquid-to-air membrane energy exchangers (LAMEEs) as the dehumidifier and regenerator.