ABSTRACT
A simple solar energy powered intermittent adsorption refrigeration system was designed, fabricated and tested. The system uses a Zeolite as the adsorberand water as the working fluid. The heat sourceis a parabolic trough concentratorwhich is to collect and concentrate solar thermal energy onto a black bodycoated copper absorber. The generator drives the refrigerant around the system through a condenser and an evaporatorto complete the refrigeration cycle. Two set of test were carried out and different times of the year, one in January 2008 a month with the lowest solar irradiation and the second set in May 2008. The system was evaluated by leaving it outside under solar radiation and monitoringtemperatures at various points on the the generator, condenser and the evaporator through the useof thermocouple sensors. The first test carried out revealed that the average highest and lowest temperaturesonthe solar collector were57.2oC and 11.5�C respectively. The average lowestrefrigeration temperature was 18�C. No cooling effect was actually produced due to the period testing was carried out and imperfection in the fabrication process. The Zeolite was produced in locally with a pore size of 4 ?and a regenerative temperature of 250oC. The second test carried out in May 2008 produced a cooling effect by making small changes on the system. An evaporator temperature of 9oC was attained which linearly increased to a maximum of 28oC as the day advanced. Maximum absorber temperature of 64oC was attained over the test period.TGA and DTA confirmed the regenerative temperature to be at 200oC and to be thermally stable at 600oC.