Energy calculator
Compressed Air Cost Calculator
Estimate the electricity cost of loaded and unloaded compressor operation. Use controller time records and measured electrical input for both states, including the power consumed while unloaded.
What this calculator does
- Include unloaded compressor consumption when estimating annual compressed-air electricity cost.
Formula used
- Loaded energy = loaded power × annual hours × loaded time percentage ÷ 100
- Unloaded energy = unloaded power × annual hours × (100 − loaded time percentage) ÷ 100
- Average input = loaded power × loaded fraction + unloaded power × unloaded fraction
- State energy cost = state energy × energy price
- Annual energy cost = loaded energy cost + unloaded energy cost
Inputs explained
- Loaded Electrical Power: Measured electrical input while the compressor supplies its loaded output.
- Unloaded Electrical Power: Measured electrical input while running unloaded.
- Time Running Loaded: Loaded hours divided by total energized hours from the controller.
- Annual Energized Hours: Recorded yearly hours in either loaded or unloaded operation.
- Energy Price: Energy tariff for the modeled operating period.
How to use the result
- Best suited to load unload control Review, compressor electricity budget.
- Variable-speed or modulating operation requires a representative measured profile. Demand charges, dryer energy and leaks are not separately modeled.
Current U.S. benchmarks
- As of Jul 2026, industrial electricity averages 9.8 cents per kWh across the U.S. (EIA), up 4.7% from a year earlier. State averages range widely, so plants should confirm against their own tariff.
- U.S. manufacturing runs at 75.7% of capacity (Federal Reserve, Aug 2026). New factory orders are up 8.5% year over year (Census).
Common questions
- Is loaded time the same as shaft load? No. Loaded time describes how long a compressor operates in a state. Shaft load describes mechanical output during that state.
- Can unloaded power be zero? Yes, if the equipment is actually stopped and its measured input is zero. A motor running unloaded usually still draws power.
- Can I use this for several compressors? Use one calculation per distinct duty profile. Combining machines requires time fractions and measured power representing the combined system.
- Is all unloaded energy avoidable? No. Some unloading may be necessary for the existing controls and demand pattern. Verify the operating change before claiming savings.
Related guides
Last reviewed 2026-10-06.