Energy flow

A compressing device, comprising:

• a turbine comprising a first inlet and a second inlet and configured to provide energy by expanding one or more mediums,
• wherein the first inlet is configured to receive a first medium of the one or more mediums, and
• wherein the second inlet is configured to receive a second medium of the one or more mediums;
• a compressor configured to:
• receive a first energy derived from the first and second mediums being expanded across the turbine during a first mode of the compressing device,
• receive a second energy derived from the first medium being expanded across the turbine during a second mode of the compressing device, and
• compress the second medium in accordance with the first mode or the second mode;
• a fan configured to receive the first energy during the first mode and the second energy during the second mode;
• and
• a power turbine configured to provide a third energy by expanding a third medium of the one or more mediums in accordance with the first mode or the second mode,
• wherein the compressor is configured to receive the third energy as a power assist from the third medium expanded across the power turbine;
• wherein the first medium and the second medium are mixed at the turbine during the first mode at a first mixing point, and wherein the first medium and the second medium are mixed downstream of the turbine during the second mode at a second mixing point.