Abstract: An apparatus and method is disclosed wherein mechanical power is returned to a prime mover producing waste heat. The apparatus includes a working fluid configured to receive thermal energy from the waste heat, a collector to hold the working fluid, an evaporator fluidly coupled to the working fluid collector for transferring the waste heat to the working fluid to change the working fluid to vaporized working fluid, a feed pump to cause the working fluid to flow between the working fluid collector and the evaporator, an expander fluidly coupled to the evaporator to receive the heated working fluid to create rotational mechanical power, and a condenser to cool the expanded working fluid. The expander is mechanically associated with the prime mover directly or via a clutch.

Abstract: A method and system for generating electrical power from geothermal, gas pressure let down, and/or heated waste steam sources utilizes a twin-screw compressor reversed to operate as an expander, wherein the expansion provides mechanical power than can be converted to electrical power utilizing a generator, without the need to utilize dry steam turbines. Multiple stages may be utilized in the expansion process.

Abstract: A method and system for generating electrical power from geothermal, gas pressure let down, and/or heated waste steam sources utilizes a twin-screw compressor reversed to operate as an expander, wherein the expansion provides mechanical power than can be converted to electrical power utilizing a generator, without the need to utilize dry steam turbines. Multiple stages may be utilized in the expansion process.

Abstract: A low grade waste heat recovery generator system is presented. The system comprises an expander generator set having a compressor rotatably coupled to a generator. The compressor rotates in a reverse direction to operate as an expander. The system also comprises a condenser fluidly coupled to the expander generator set, a refrigerant pump fluidly coupled to the condenser, an evaporator fluidly coupled to the refrigerant pump and the expander generator set, and a working fluid configured to flow from the evaporator to the expander generator set, to the condenser, and to the refrigerant pump in a closed loop Organic Rankin Cycle. The working fluid is heated to a temperature of about 140 ° F. to about 300 ° F.