Pressing the Efficiency Button
Why it’s time to move beyond inlet valve modulation for compressor control
By David M. McCulloch
The type of compressor capacity control you use and the related pressure settings you select are critical to your overall compressed air system efficiency. For years, many rotary compressors were sold with inlet valve modulation (throttling) as the standard means of capacity control. While this matched compressor output with demand, the system offered much less than desirable energy efficiency.
However, there are ways to improve things.
In many plants, compressed air production started with one compressor. Then, as demand increased, another compressor was added and then another. For example, consider a system having three rotary compressors, each using inlet valve modulation capacity control.