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.