An autonomous solar driven adsorption cooling system

摘要

Attempts to develop autonomous solar adsorption chillers without additional controls to regulate system operation have yielded low cooling capacity and poor coefficients of performance (COPs) due to the use of the sun's diurnal cycle for control of system operation. A thermally driven, solar adsorption chiller with consistent cooling rates is investigated here. A model for a single-bed system is considered with activated-carbon/ammonia as the working pair. The modeled heat input corresponds to 1 m(2) of collector area. Autonomous operation is achieved using novel thermally activated controls to regulate the heating and cooling of the adsorbent bed, rather than relying on the solar cycle. Heat from the collector is stored in a hot-side thermal mass during the adsorption phase, and cooling is delivered by an air-cooled heat sink. The system does not require pumping power or any auxiliary systems for operation. The simple design and elimination of expensive complex components make this system ideal for cooling applications in the developing world or in installations not connected to the grid.