In the processes where the machine is operated continuously,
the energy consumption is by far the largest factor in life-cycle
costs. Therefore, even a seemingly small efficiency improvement
can have a substantial effect on the environmental impacts of the
machine operation. In this study, for a single compressor the
annual reduction in greenhouse gas emissions ranged from 5 to
9.5 t CO2-eq. In case of the scenario with the highest energy saving
potential, Scenario 3 (VNLD), the price for the avoided
CO2-emissions would be roughly 0.10 €/kgCO2. The example waste
water treatment plant has two to three compressors running
simultaneously, so the savings would actually be two to threefold.
It should be noted, however, that the energy savings are always
system specific, and depend on the required output.