Variable speed compressors, as their name suggests, allow their speed to be varied – and this can have substantial benefits in terms of component wear and overall energy usage.

Writing in the International Journal of Advanced Technology in Engineering and Science, a team from Sunrise University describe their experiences in testing with a variable speed compressor.

“There is a huge possibility of saving electric power as well as component life by lowering delivery pressure, as well as lowering the motor speed of the compressor,” they claim.

In their study, the team used a micro-controller to adjust the speed of their compressor, allowing them to reduce the pressure at which the air was delivered.

They describe the benefits of operating at 5 bar instead of 8 bar – not only including lower electricity consumption, but also a reduction in leakage from the system.

“A reduction in delivery pressure by 1 bar would reduce electric power [consumption] by 7-10%,” they add.

Later in their article, the authors describe compressed air leakage as “pouring money down the drain”, suggesting variable speed compressors or retro-fitted variable drive systems as a possible solution to this problem.