Design of solar powered adsorption heat pump with ice storage

The design and performance of a solar (and/or natural gas) powered adsorption (desiccant-vapor) heat pump for residential cooling (and heating) is described. The entire system is modeled and analyzed: adsorption heat pump itself, ice thermal storage reservoir, and solar collectors. The adsorption heat pump embodies patent pending improvements to the state-of-the-art which elevate coefficient of performance for cooling from a maximum of 1.2 reported in the literature to a conservatively predicted minimum of 1.5. The adsorption device utilizes economical, robust configurations (shell-and-tube) and components (helical annular finned tubes, multi-lumen tubes) commonly employed in heat exchangers in a manner heretofore untried, as well as other enhancements (metal wool to diffuse heat throughout the adsorbent). The vessel is all aluminum and the adsorbent-refrigerant pair is carbon-ammonia. The ice reservoir provides 24 h cooling. Two types of solar collector are determined to be satisfactory at the selected operating temperature of 170 degrees C: (1) compound parabolic concentrator with high concentration ratio (10+) and automatic tilt adjustment, and (2) evacuated (0.001 arm) flat panel, similar to atmospheric pressure versions employed for domestic water heating. (c) 2006 Elsevier Ltd. All rights reserved.