A variable effect absorption refrigeration cycle is proposed which can obtain a rising COP (Coefficient of Performance) versus the rising generation temperature. This novel cycle could be applied for solar absorption cooling efficiently. In this paper, a 50 kw variable effect (also named as 1.n effect) absorption chiller using LiBr-water as working fluid was designed. Its rated condition is generation temperature of 125 degrees C, condensation temperature of 40 degrees C, absorption temperature of 35 degrees C and evaporation temperature of 5 degrees C. The variable effect absorption chiller was then manufactured and tested. Data from the experiment showed that the chiller can get a rising COP from 0.69 to 1.08 under generation temperature from 95 degrees C to 120 degrees C as it was expected. The average error between theoretical COP and experimental COP was 7.3%. Feasibility of the variable effect absorption chiller and the effectiveness of the design have been verified. (C) 2014 Elsevier Ltd. All rights reserved.