Patent ID: 7284376

Claim:
A method for producing power from a heat source comprising the steps of: a) heating nonane with heat from said heat source and producing vaporized nonane in an intermediate fluid heater/vaporizer; b) expanding said vaporized nonane in an intermediate fluid vapor turbine, thereby producing power and expanded vaporized nonane, said turbine mounted on a shaft; c) supplying said expanded vaporized nonane to an organic fluid vaporizer for supplying heat to liquid organic working fluid present in said organic fluid vaporizer; d) vaporizing said liquid organic working fluid with heat from the expanded vaporized nonane in said organic fluid vaporizer to form vaporized organic working fluid and a nonane condensate such that a portion of said condensate is used to cool a seal of said shaft by cooling and condensing hot pressurized vapor near said seal, and liquid containing such condensed hot pressurized vapor is supplied to a condensate drain vessel, the drained condensate being supplied to a line connected to a cycle pump of the nonane intermediate cycle; e) expanding said vaporized organic working fluid in an organic vapor turbine for producing expanded vaporized organic working fluid; f) generating power by use of an electric generator driven by said organic vapor turbine; g) condensing said expanded vaporized organic working fluid to produce organic working fluid condensate; and h) supplying the organic working fluid condensate to the organic fluid vaporizer.