Theoretical and experimental investigation of the performance of a desiccant air-conditioning system

Solid desiccant air-conditioning systems present an interesting alternative solution with regard to the conventional vapour compression systems, in the sense that they do not use any refrigerants and they present the opportunity to exploit thermal energy, and more specifically solar thermal energy, instead of electrical energy. In the present work a theoretical model is presented for the operation of a desiccant air-conditioning system, developed on the basis of existing approaches for the modelling of the main subsystems of such a device. The model is experimentally validated on a real scale system, through the exploitation of a significant number of measurements, which correspond to a typical range of operation conditions for these systems. The proposed model is used for the investigation of the performance of a system with a typical set-up, examining the influence of parameters such as the weather conditions, the level of the imposed cooling load, the efficiency level of the main subsystems of the set-up, the air flow rate and the regeneration temperature. The results confirm the potential of the examined technology to satisfy actual cooling loads, and at the same time they lead to specific conclusions for the operation of these systems.