One of the best ways to save compressed air system energy is to reduce the load on the compressor by fixing leaks. The table shown at right calculates the approximate cost of leaks by orifice size for a typical 100 psi system.
The average compressed air system wastes about 15% to 30% of all the compressed air produced — and this goes directly onto your energy bill. This percentage range is almost like a stupidity tax on your electricity costs, because the cost is ongoing and continuing day after day, but something can be done about it, therefore you are stupid not to repair these money wasters that are stealing money from your pocket.
Of course, the leaks shown in the chart above are for perfectly round orifices, but compressed air leakage is anything but standard. The leakage occurs in loose fittings, failed drains, cracked hoses, partly open valves and in many other problematic ways. The challenge is to find all these and fix them.
Often, in a standard shop the leakage can be heard by the naked ear. If you fix all the ones you can hear, you are well on your way to saving. But in noisy environments you will need the assistance of a good quality ultrasonic leak detector.
There was a time when leak detectors were very expensive, however, these days the prices are coming down to very affordable levels. Adequate quality leak detectors can be purchased for under $500 these days, there is no excuse not to have at least one in your shop. The hard part is pulling it out of the box and using it.
Wondering how much you are leaking? If you only have one compressor running during non-production times you can easily do a timer test to estimate your leakage flow by calculating the compressor duty cycle. Or do a simple receiver draw down test to estimate your waste. The instructions for this are in a publication called Improving Compressed Air System Performance: A Sourcebook for Industry, available by searching in your browser.