Abstract: A high efficiency air conditioning and refrigeration system and cycle comprises a vapor compressor and two independent ejectors operatively connected to high and low-pressure sides of the compressor, respectively. The two ejectors reduce the overall pressure ratio of the mechanical vapor compressor resulting in dramatically increased thermodynamic cycle efficiency. As one example of its potential applications for residential, commercial or industrial uses, a 150 ton capacity of a water-cooled chiller designed in accordance with the present invention is predicted to provide the power consumption as low as 0.47 kW/ton, when operated in accordance with the cooling methods of the present invention, which corresponds to 7.47 of Coefficient of Performance (COP).