How much do you save with a permanent magnet VSD?
Enter your compressor power, your annual running hours and your kWh price. The calculator estimates the annual saving, the current bill and the CO₂ avoided.
How much is your old compressor costing you?
Quick estimate with 3 sliders, on an assumed 32% saving to refine with your load profile. Full audit on request.
How this calculation works.
The calculator estimates the energy saving of a permanent magnet VSD against an equivalent fixed-speed compressor, at an average load of 60% (typical industrial profile).
Typical general industry profile. The ratio can rise to 80% under steady load (steelmaking) or fall to 40% under very variable load.
The case of a screw regulated by inlet modulation, which still draws about 88% of its power at 60% flow according to the US Department of Energy Sourcebook: the drive removes close to a third of it. Against a load/unload screw the gap is smaller, 9 to 19% of consumption. Only an on-site measurement gives yours.
Carbon intensity of electricity generated in the United Kingdom in 2024, over its whole life cycle (Ember, processed by Our World in Data). The country follows the language of the page, like the default kWh price.
The saving follows running hours: half as large at 2,000 h/yr, where variable speed loses its point. 4,000 h/yr is the slider's starting value: set it to your compressor's actual hours.
Refine these figures with a site audit.
Our technical team installs a data logger on your current compressor for 7 days and gives you the precise calculation from your real load profile. Free audit, no commitment.