Specific Power, VFD Air Compressor System

I'm used to 'specific' being per unit of mass, but the column heading says KW/100 SCFM, so it would presumably be total input power (KW) times 100 divided by the flow in SCFM. The table shows that at 25% load, the compressor uses only about 10% more power per SCFM that at full load. That seems pretty good to me. Is this for a new compressor? What kind? If you had power and flow meters installed, you could monitor how this changes over time.

I can say without a doubt that specific power will change with changes in ambient conditions, as the ability of the air to be worked on changes up or down, and

also the compressor may or may not dissipate heat as well in worst case conditions.

If the compressor is running at ISO conditions (normalized to a set known humidity, 60 F, and 1 sea level atmosphere pressure, then it should be straightforward to rate one compressor

against another one. The specific power can be rated in mass flow units (Lb, or Kg), or standardized flow units (SCFM, or SLPM), as long as these unit are consistent across

the comparison. If needing to convert mass flow to volume flow, just utilize the ideal gas law for air (Google it for crying out loud), PM=ρRT. Thus, one can see there is a volume constant per mole of

any gas under consideration. Usually standard molar volume of a gas is approximately 22.4140 L/mole.

Thank you guys! I got it.