A method for producing power from a heat source comprises the steps of:
heating an intermediate fluid with heat from the heat source and
producing a vaporized intermediate fluid in an intermediate fluid
heater/vaporizer. Heat from the vaporized intermediate fluid vaporizes an
organic liquid working fluid present in an organic working fluid
vaporizer to form a vaporized organic working fluid and intermediate
fluid condensate. The vaporized organic working fluid is expanded in an
organic vapor turbine for generating power and producing expanded
vaporized organic working fluid; the expanded organic vaporized working
fluid being condensed to produce an organic fluid condensate with the
organic fluid condensate being supplied to the organic fluid vaporizer.
According to the present invention, prior to supplying the vaporized
intermediate fluid to the organic fluid vaporizer the vaporized
intermediate fluid is expanded in an intermediate fluid vapor turbine and
power is produced.