Abstract: A system having a matched vane compressor and impeller is described for use in either a hydraulic system or in a two phase air conditioning system. The impeller is matched to the compressor to return work to the compressor through a shaft or gearbox. The compressor is a vane compressor having longitudinally reciprocating vanes carried in a slotted disc between matched, opposed cam faces forming a series of variable geometry chambers which draw in and expel working fluid during rotation of the shaft. Compression is achieved by exposing the fluid in the chambers to high pressure fluid while the volume of the chamber is not changing. A pressurizing port is placed tangentially to the chambers for this purpose. The impeller also makes use of tangentially disposed pressure ports to expose the turning pockets of a drum to higher pressure.