Energy worked example
Compressed Air Cost at 50% average load: a worked example
This worked example runs the compressed air cost numbers for a tougher week than the baseline: 50% average load instead of the typical 70%. Estimate compressor energy cost from horsepower, load, hours, and electricity rate.
The inputs for this scenario
- Compressor horsepower: 50 HP (held at the documented default)
- Average load: 50 % (the input this scenario stresses; the baseline uses 70)
- Run hours per day: 16 hr (held at the documented default)
- Operating days per year: 250 days (held at the documented default)
- Electricity rate: 0.12 $ / kWh (held at the documented default)
Working through the calculation
- The calculation starts from the formula this tool documents: kW = horsepower × 0.746 × load.
- Annual air cost works out to 8,952 $ / yr at these inputs, and this is the headline figure for the scenario.
- Compressor load works out to 18.65 kW at these inputs.
- Annual energy works out to 74,600 kWh at these inputs.
- Cost per day works out to 35.81 $ / day at these inputs.
How this compares with the baseline
- Against the tool's baseline example, where average load sits at 70% and the headline result is 12,533 $ / yr, this scenario comes in 28.57% below the baseline at 8,952 $ / yr.
- Use it during energy audits, when sizing or replacing a compressor, or to build the business case for leak repair, sequencing controls, or off-shift shutdown. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.
Results at a glance
- Annual air cost: 8,952 $ / yr (headline result)
- Compressor load: 18.65 kW
- Annual energy: 74,600 kWh
- Cost per day: 35.81 $ / day
Run it with your numbers
- To rerun this with your own numbers, open the live Compressed Air Cost calculator, set average load to your actual value, and adjust the remaining inputs to match your operation.
Last reviewed 2026-05-12.