In the study, we propose a hybrid air-conditioning cycle of mechanical vapour compression and thermal vapour compression. In the bottoming cycle, the refrigerant is compressed by a mechanical compressor from the evaporator to the medium pressure condenser. In the topping cycle, the other refrigerant is compressed by adsorption phenomena, where low temperature heat is used as a driving force, from the medium pressure condenser to the higher pressure condenser. R 1234ze is the refrigerant of the mechanical compression cycle, while CO2 is the refrigerant of the thermally compression cycle, where the activated carbon is the adorbent of CO2. Based on the measured adsorption kinetics of CO2 on the activated carbon, the system is modelled using MATLAB/SIMULINK. The dynamic characteristics of the system is investigated by simulation, and the reduction in mechanical power for the mechanical compressor is revealed.