One of the most effective ways to save energy when it comes to compressed air is to reduce system flow. This requires dealing with the end uses and abuses of compressed air in an effort to eliminate or reduce the flow of compressed air that results from wasteful practices.
One often-cited opportunity for improvement is leak reduction – a valuable endeavor, but more can be done. Additional significant savings can be achieved by finding and fixing “inappropriate uses,” which we can define as some sort of process that could be more cost-effectively supplied by another energy source. This is not a simple process: There are hundreds if not thousands of individual uses of compressed air in most plants. With that in mind, though, let’s explore some of the more common potentially inappropriate uses of compressed air and look at examples of how plants have addressed these energy-wasters.
How efficient is compressed air?
One of the problems with compressed air is the high cost of the power input that feeds the air compressors compared with the actual mechanical power that comes out at a compressed-air-powered device.
An example often used is the output of 1 horsepower using a vane-style air motor. A vane motor rated at 1 hp produces about 0.746 kW of rotational power from its shaft and translates this to a rotary motion that can drive a tool or a mixer. If typical specifications are consulted, we might find that this motor will consume 40 cfm at 100 psi to produce this level of power.