A method for converting heat energy into a higher-value energy using a rotary vane piston motor to which a working circuit for a working fluid is connected, characterised in that - the rotary vane piston motor comprises two vane-shaped pistons (41, 42) rotatably mounted on a shaft, from which the generated torque is accepted by a drive shaft, optionally via a gear unit with non-round wheels, - in that the working fluid emerging from the rotary vane piston motor is liquefied in a cooling unit and/or in a condenser and is supplied in the liquefied state, optionally via a collector preferably provided with a filter, to a pressure pump and is supplied from the latter via a heat exchanger arranged in front of the cooling unit for heat absorption, to a further heat exchanger for heating and/or evaporation and is supplied from this further heat exchanger, optionally via an adjustable valve, in particular a sensor valve, in expanded form, to the chambers of the rotary vane piston motor in order to move the pistons (41, 42), and - in that the working fluid is liquefied in the condenser and then subsequently evaporated again in the further heat exchanger, wherein - Solkane ES36 or Solkatherm SES36 or a comparable organic working fluid is used as the working fluid, which is liquefied in the condenser or the cooling unit and is subsequently evaporated again in the further heat exchanger, - in that the pressure of the working fluid is set, directly before (at 1') the rotary vane piston motor, to between 3 bar and 10 bar, in particular to between 6 bar and 10 bar, directly after (at 2') the rotary vane piston motor, to between 0.4 bar and 0.8 bar, directly before (at 3') the condenser, to between 0.4 bar and 0.8 bar, directly before (at 4') the pressure pump, to between 0.4 bar and 0.8 bar, directly after (at 5') the pressure pump, to between 2 bar and 100 bar, preferably between 3 bar and 10 bar, in particular to between 6 bar and 10 bar, directly after (at 6') the heat exchanger, to between 2 bar and 100 bar, preferably between 3 bar and 10 bar, in particular to between 0.4 bar and 0.8 bar, directly after (at 1') the further heat exchanger, to between 3 bar and 10 bar, in particular to between 6 bar and 10 bar, and - in that the temperature of the working fluid is set directly before (at 1') the rotary vane piston motor, to between 60°C and 180°C, in particular to between 100 and 140°C, directly after (at 2') the rotary vane piston motor, to between 0°C and 70°C, in particular to between 20 and 40°C, directly before (at 3') the condenser, to between 20 and 40°C, directly before (at 4') the pressure pump, to between 0°C and 70°C, in particular to between 20 and 40°C, directly after (at 5') the pressure pump, to between 0°C and 70°C, directly after (at 6') the heat exchanger, to between 0°C and 70°C, in particular to between 20 and 40°C, directly after (at 1') the further heat exchanger, to between 60°C and 180°C, in particular to between 100 and 140° C. - the rotary vane piston motor comprises two vane-shaped pistons (41, 42) rotatably mounted on a shaft, from which the generated torque is accepted by a drive shaft, optionally via a gear unit with non-round wheels, - in that the working fluid emerging from the rotary vane piston motor is liquefied in a cooling unit and/or in a condenser and is supplied in the liquefied state, optionally via a collector preferably provided with a filter, to a pressure pump and is supplied from the latter via a heat exchanger arranged in front of the cooling unit for heat absorption, to a further heat exchanger for heating and/or evaporation and is supplied from this further heat exchanger, optionally via an adjustable valve, in particular a sensor valve, in expanded form, to the chambers of the rotary vane piston motor in order to move the pistons (41, 42), and - in that the working fluid is liquefied in the condenser and then subsequently evaporated again in the further heat exchanger, wherein - Solkane ES36 or Solkatherm SES36 or a comparable organic working fluid is used as the working fluid, which is liquefied in the condenser or the cooling unit and is subsequently evaporated again in the further heat exchanger, - in that the pressure of the working fluid is set, directly before (at 1') the rotary vane piston motor, to between 3 bar and 10 bar, in particular to between 6 bar and 10 bar, directly after (at 2') the rotary vane piston motor, to between 0.4 bar and 0.8 bar, directly before (at 3') the condenser, to between 0.4 bar and 0.8 bar, directly before (at 4') the pressure pump, to between 0.4 bar and 0.8 bar, directly after (at 5') the pressure pump, to between 2 bar and 100 bar, preferably between 3 bar and 10 bar, in particular to between 6 bar and 10 bar, directly after (at 6') the heat exchanger, to between 2 bar and 100 bar, preferably between 3 bar and 10 bar, in particular to between 0.4 bar and 0.8 bar, directly after (at 1') the further heat exchanger, to between 3 bar and 10 bar, in particular to between 6 bar and 10 bar, and - in that the temperature of the working fluid is set