Adsorption-compression cascade cycles: An experimental study

In this paper the experimental testing of a cascade chiller composed of an adsorption unit and a vapour compression unit is reported. The operation of the cascade under realistic operating conditions, differing for the temperature of the heat source available and the environmental temperature is analysed. A comparison was made between the application of the cascade and a vapour compression chiller only for air conditioning applications. According to the heat source temperatures, an increase in the electric COP of the system ranging from 25% to 50% was measured, with a maximum value of 8. An optimization of the system was subsequently proposed, by evaluating different adsorbent materials and refrigerants through the use of thermodynamic models. The theoretical study revealed that a performance up to 110% higher with respect to traditional chillers could be obtained if the cascade was used in refrigeration applications.