Experimental investigation of energy and exergy performance of short term adsorption heat storage for residential application

Energy and exergy performance of adsorption storage system was studied experimentally for residential application. A fin-coated heat exchanger was adopted for a sorption bed to quicken the charging process. When the regeneration temperature was 70°C, ambient temperature was 30°C, HTF (heat transfer fluid) inlet temperature for the adsorption bed was 30°C, results showed that the heat ESD (energy storage density) was approximately 805kJ/kg with the energy efficiency approximately 96%. The exergy efficiency was 26.7% and the loading difference was 0.164. In this study the mass flow rate of the adsorption bed affected more on the storage performance than that of the desorption bed. As the mass flow rate was increased, the ESD increased while the exergy efficiency decreased due to the larger exergy destruction caused by pressure drop. Increasing regeneration temperature and decreasing adsorption temperature could make the ESD and energy efficiency increased, but the exergy efficiency decreased. As ambient temperature was increased, total ESD and energy efficiency increased, and overall exergy efficiency decreased. A larger loading difference could be achieved with increasing the adsorption bed HTF mass flow rate, regeneration temperature, and inlet temperature of HTF for the evaporator, or decreasing inlet temperature of HTF for the adsorption bed.