Abstract: A thermodynamic installation with a closed circuit for a working medium employing a compressor and an expansion machine connected thereto; or by a transmission linked by a first heat exchanger and second heat exchanger having the working medium in the heat exchangers and expansion machine continuously in a vapor-liquid phase equilibrium and that complete circulation takes place within the vapor-liquid phase area of the temperature-entropy diagram. The installation can be employed as a heat pump or to provide energy as a turbine resulting in an increased yield.