An innovative solar-driven directly air-cooled LiBr-H2O absorption chiller prototype for residential use

In this study, experimental trials were conducted on an innovative solar-driven, directly air-cooled, single effect, 4.5 kW-LiBr/H2O absorption chiller prototype. The aim was to air-condition a 40-m2 room located in Madrid. The solar facility consisted of a vacuum flat-plate collector field, with a total aperture area of 42.2 m2, a 25-kW external plate heat exchanger and a 1.5-m3 storage tank. The paper reports the findings in detail, including solar cooling facility temperatures and thermal power, solar fraction, COP and SCOP values on a day when the outdoor dry bulb temperature ranged from 30 to 37.7 °C. The daily results for the entire trial are also given. No solution crystallization problems arose inside the prototype even when the generator feed temperature reached 109 °C. The lowest chilled water temperature attained was 14.3 °C, and the mean COPth and SCOP values were 0.53 and 0.06, respectively. This study forms part of a larger project whose aim is to use solar power as a source of heat in air-cooled absorption chillers in residential buildings.