NOVELTY - A first portion of a lean liquid stream is pressure adjusted to have the same pressure as an incoming stream. A second portion of the lean liquid stream is pressure adjusted to have the same pressure as a pre-basic solution stream. The streams comprise at least one lower and at least one higher boiling component. The compositions of the streams are the same or different while the composition of the incoming and outgoing streams is the same.    USE - For power extraction systems utilizing multi-component working fluids.    ADVANTAGE - Provides improved efficiency, thereby offsetting additional cost.    DETAILED DESCRIPTION - A separation subsystem has a separator that produces a rich vapor stream and the lean liquid stream. A heat exchange subsystem has three heat exchangers and two throttle control valves that mix a pressure adjusted first portion of the lean liquid stream with the incoming stream to form the pre-basic solution stream, and mix a pressure adjusted second portion of the lean liquid stream with the pre-basic solution stream to form a basic solution stream. A first portion of a pressurized fully condensed basic solution stream is brought into a heat exchange relationship with the pre-basic solution stream to form a partially condensed basic solution stream. A first condensing and pressurizing subsystem has a first condenser and a first pump to fully condense the partially condensed basic solution stream to form a fully condensed basic solution stream, and to pressurize the fully condensed basic solution stream to form a pressurized fully condensed working fluid stream. A sec! ond condensing and pressurizing subsystem has a second condenser and a second pump to mix a second portion of the fully condensed basic solution stream and the rich vapor stream to form an outgoing stream, to fully condense the outgoing stream and to pressurize the outgoing stream to a desired high pressure.    DESCRIPTION OF DRAWING(S) - The figure is a block diagram of the modular condensation and thermal compression subsystem.    Heat exchanger (HE1-HE8)