The compressors use electricity for all the air they make, whether a press uses it or it leaks away.
Each leak fixed is air they no longer make.
A lower pressure takes less work for the same air, and pushes less air out of any leak that is left.
Math
We estimate the compressors use 12 percent of the $600,000 electricity bill, about $72,000 per year.
We assume leaks that can be fixed waste 10 percent of that, about $7,200.
Holding 6 psi more than the presses need costs another 3 percent, about $2,200, at about 1 percent for every 2 psi.
Together that is about $9,400 per year.
After about $800 per year for a leak walk each quarter, about $8,600 is left.
The detector and the staff hours cost about $2,300 once, paid back in about 3 months.
Industry evidence
US Department of Energy guidance says leaks often waste 20 to 30 percent of a compressor's air where nobody looks for them, and under 10 percent where they are repaired.
It names an ultrasonic detector as the best way to find them.
For a system near 100 psi, it says a compressor's energy rises about 1 percent for every 2 psi.
None of this was measured at this plant.
Limitations
On our visit we could not hear a leak or read a pressure, so either part could be zero.
The plant may already check its air lines for leaks.
An idling compressor still uses 15 to 35 percent of its full power, so the bill falls less than the air does, unless the compressors switch off when idle.
New leaks open as hoses wear, so the saving lasts only while the leak walk is repeated.
Illustrative sample. The plant, the walk and the footage are synthetic. Figures from our analysis are estimates made with AI, not guarantees.