Abstract: The refrigeration cycle uses an evaporation zone prior to compression and a condensation zone after the latter, in which the thermodynamic fluid used in the cycle as well as the fluid used in the cold-exchange and heat-exchange cycles is water. The installation is operated on the basis of dynamic compression in two separate compression stages linked to one another by at least one zone with de-superheating and enclosed in a hermetically sealed and heat-insulated enclosure confining the vapor at very low pressure; the wheels of these two stages are mounted directly on the opposite ends of the shaft of a common, sealed, variable speed electric motor disposed inside the enclosure between these stages.