Abstract: A system for producing power using an organic Rankine cycle (ORC) includes a turbine, a generator, an evaporator, an electric heater, an inverter system and an organic Rankine cycle (ORC) voltage regulator. The turbine is coupled to the generator for producing electric power. The evaporator is upstream of the turbine and the electric heater is upstream of the evaporator. The evaporator provides a vaporized organic fluid to the turbine. The electric heater heats the organic fluid prior to the evaporator. The inverter system is coupled to the generator. The inverter system transfers electric power from the generator to a load. The ORC voltage regulator is coupled to the inverter system and to the electric heater and it diverts excess electrical power from the inverter system to the electric heater.

Abstract: A system has a compressor. A heat rejection heat exchanger is coupled to the compressor to receive refrigerant compressed by the compressor. An ejector has a primary inlet coupled with heat rejection heat exchanger to receive refrigerant, a secondary inlet, and an outlet. The system has a heat absorption heat exchanger. The system includes means for providing at least of a 1-10% quality refrigerant to the heat absorption heat exchanger and an 85-99% quality refrigerant to at least one of the compressor and, if present, a suction line heat exchanger.

Abstract: A system (200; 300; 400; 500; 600) has a compressor (22; 200, 221). A heat rejection heat exchanger (30) is coupled to the compressor to receive refrigerant compressed by the compressor. An ejector (38) has a primary inlet (40) coupled to the heat rejection heat exchanger to receive refrigerant, a secondary inlet (42), and an outlet (44). A separator (48) has an inlet (50) coupled to the outlet of the ejector to receive refrigerant from the ejector, a gas outlet (54), and a liquid outlet (52). One or more valves (244, 246, 248, 250) are positioned to allow switching of the system between first and second modes.

Abstract: A method and system for operating a cascaded organic Rankine cycle (ORC) system (100) utilizes two waste heat sources from a positive-displacement engine (106), resulting in increased efficiency of the engine (106) and the cascaded ORC system (100). A high temperature waste heat source from the positive-displacement engine (106) is used in a first ORC system (102) to vaporize a first working fluid (118). A low temperature waste heat source from the positive-displacement engine (106) is used in a second ORC system (104) to heat a second working fluid (130) to a temperature less than the vaporization temperature. The second working fluid (130) is then vaporized using heat from the first working fluid (118). In an exemplary embodiment, the positive-displacement engine (106) is a reciprocating engine. The high temperature waste heat source may be exhaust gas and the low temperature waste heat source may be jacket cooling water.

Abstract: A method and system for recovering oil is used in an organic rankine cycle (ORC) system to recover oil from an evaporator of the ORC system and return the oil to an oil sump. The ORC system includes an evaporator, a turbine, a condenser and a pump, and is configured to circulate a refrigerant through the ORC system. The oil recovery system includes a recovery line configured to remove a mixture of oil and refrigerant from the evaporator. The mixture of oil and refrigerant passes through a heat exchanger in order to vaporize liquid refrigerant in the mixture and produce a mixture of oil and vaporized refrigerant. A delivery line is configured to deliver the mixture of oil and vaporized refrigerant to the turbine, at which point the oil may be separated from the vaporized refrigerant and recycled back to the oil sump.

Abstract: A system for providing a cold environment which has a number of cooling stages with variable displacement volumes into which input fluid from a compressor flows in an input channel to and from the displacement volumes and output fluid flows in an output channel to the compressor. Volume changers vary the volumes of the displacement volumes and input fluid flowing to a first set of displacement volumes is pre-cooled by regenerative heat exchange and counterflow heat exchange and input fluid flowing to the final displacement volume is pre-cooled primarily by counterflow heat exchange. The volume changer at at least one of the stages is thermally decoupled from the input and output channels.