Calculation reviewed: 4 October 2026 · Engineering Desk Tools
How to use the Compressed air leak cost & payback calculator
Compare up to three measured leaks, annual electricity waste and repair payback. Start with measurements or documented values for the equipment and reporting period you actually want to assess. The calculator does not fill in a typical installation for you. Its blank fields help keep a demonstration value from being mistaken for your own operating data.
Choose the required options, enter the values in the labelled units and select Calculate. If a field is rejected, check its range and unit before changing it. The result is accompanied by the equation and assumptions so you can decide whether it answers your engineering question.
Inputs and measurement basis
- Leak 1 free-air flow (L/min). Measured free-air leak flow in litres per minute, for example from a flow meter or leak-down test.
- Leak 2 free-air flow (L/min, optional). A second measured leak in L/min. Leave blank if there is none.
- Leak 3 free-air flow (L/min, optional). A third measured leak in L/min. Leave blank if there is none.
- Compressor specific power (kW per m³/min). Compressor specific power in kW per m³/min at the operating pressure. The value must be greater than zero.
- Pressurized hours per year. Hours per year the air network is pressurised, including nights and weekends. The allowed maximum is 8784.
- Electricity tariff / kWh (your currency). Electricity price per kWh in your currency.
- Total repair cost (your currency). Total cost to fix these leaks, in the same currency.
- Expected leak reduction (%). Share of the leak flow you expect to remove, as a percentage. The allowed maximum is 100.
Record the measurement source and operating condition. Retain unrounded values for verification.
Method and interpretation
Measured leak flow is preferable to a guessed hole diameter. Flow and compressor specific power must refer to the same free-air basis. Use network pressurization hours, which can include nights and weekends when production is stopped. Proportional energy savings are only a screening assumption; compressor control behavior can change the actual benefit.
Leak kW = flow (L/min) / 1000 × specific power (kW per m³/min). Annual energy = leak kW × pressurized hours. Annual savings = energy × tariff × reduction / 100. Payback (years) = repair cost / annual savings.
Use measured free-air flow and compressor specific power on the same reference basis. Blank optional leak fields count as zero. The network can leak outside production hours. This screening estimate assumes compressor electricity falls in proportion to removed flow; actual savings depend on compressor controls and unloaded power. Tariff and repair cost must use the same currency. No automatic tariff or exchange-rate assumptions.
Worked example
This example does not populate the form. Enter your own installation data.
Calculated result: 720 annual cost. Estimated total leak flow: 150 L/min. Costs use your entered currency. Payback excludes financing, maintenance changes and taxes.
Check the arithmetic independently using the displayed equation. Retain intermediate precision and compare the final value with your equipment documentation.
Quick-reference table
These illustrative rows retain the worked example assumptions except for the varied input. They are not certified ratings or manufacturer data. Use the form for intermediate values.
Common mistakes
Using production hours while the network stays pressurized overnight; mixing litres per minute with cubic metres per minute; assuming repair removes all leakage without verifying it. Before relying on the output, check the decimal format, unit scale and source of each value. Recheck unusual results against the formula.
Frequently asked questions
Are the example values used automatically?
No. Inputs remain blank when the tool opens or when you clear them. The worked example and table are reading material below the calculator. Enter the actual values you want to check each time, and label saved reports so their context is not lost.
What does the result mean?
The results estimate the yearly electricity cost of the leaks, the expected saving after repair and the simple payback. They exclude compressor control effects, so confirm the saving against measured electricity use after repair.
Can I use a zero or a negative value?
The allowed range follows the meaning of each input. A divisor needs a positive value; other fields may allow zero. Check the form labels and error message rather than forcing an invalid value. A rejected input must be corrected before a result can be shown.
Is this a final design or equipment approval?
No. Use measured free-air flow and compressor specific power on the same reference basis. Blank optional leak fields count as zero. The network can leak outside production hours. This screening estimate assumes compressor electricity falls in proportion to removed flow; actual savings depend on compressor controls and unloaded power. Tariff and repair cost must use the same currency. No automatic tariff or exchange-rate assumptions. Use the calculation as support for a checked decision, and review equipment documentation and applicable requirements before changing an installation or operating setting.
How can I save or share a calculation?
Calculate first, then use Copy result or Print report. Some maintenance tools also provide a CSV summary. Reports contain your own entered data, so review them before sharing. You can share the public page URL without including plant records or confidential measurements.
How do I report an unexpected result?
Use the Contact page and include the tool URL, input values, units, expected output and the reference you used. Explain the measurement basis. Exclude confidential information.
Related tools and records
Use related calculations with consistent units, periods and equipment scope.
Embed this calculator
Copy this code into your website. The calculator stays free, with a visible attribution link. Visitors can use it without signing up.