Hybrid heat-pump-driven liquid-desiccant system: Experimental performance analysis for residential air-conditioning applications

A compact heat-pump-driven liquid-desiccant air-conditioning unit for residential buildings is proposed and constructed to validate its energy and air-conditioning performance experimentally. By composing the system with one set of providing the decoupled control of annual sensible and latent loads, the proposed system would contribute to the residential applicability as a packaged multi-functional air-conditioning system. The proposed system consists of a liquid-desiccant dehumidifier to accommodate the latent load and a heat-pump to meet the sensible load of the conditioned zone. The heat-pump also simultaneously accommodates the desiccant-solution cooling and heating demands required in the operation of the liquid-desiccant system. The operating and energy performances of the proposed system for representative summer and winter modes are monitored through a fullsize test mock-up in a laboratory. The measurement data reveals that the proposed system can consistently maintain the target supply-air temperature and humidity in each operation mode. In terms of energy efficiencies, the proposed system exhibits an energy efficiency ratio of 7.72 for the summer and a coefficient of performance of 2.51 for the winter operating conditions, which satisfy the approved minimum efficiency requirements. In conclusion, the proposed system has a great application potential for residences in terms of operating and energy performances.