ndustrial companies can save a tremendous amount of money by carefully tending to their compressed air systems.
The Strategic Energy Groups’ Ed Birch points to the easy gains that can be made by taking better care of this ubiquitous industrial and commercial platform. He says that leaks generally occur in the last 30 feet of the line. And they are costly: A one-quarter inch leak at 10 pounds per square inch (PSI) at 7 cents per kWh can create a $11,735 hole in the budget. On the flip side, he says, reducing compressed air pressure by 2 psi can reduce overall electrical use by 1 percent.
Birch’s piece at Industry Week is full of impressive numbers. Consider a section entitled “streamline idle time and changeovers”:
Idle time such as downtime and changeovers is one of the top energy wasters in today’s manufacturing plants. I’ve seen several instances where air compressors were running 24/7, and over weekends, to heat a facility’s space. By simply reviewing the compressor operating schedule and only running the machine when needed, it saved one plant 182,306 kWh — or $18,230.
Quincy Compressor of Bay Minette, AL, offered advice on the value of good air compressor maintenance. A company post said that buying and installing equipment only represents 12 percent of ongoing costs. Maintenance accounts for another 12 percent and the electricity needed to operate machines represents the balance. The post provides a detailed outline on how to determine costs. It also provides nine steps to cutting costs. These range from the obvious (“turn off your air compressor,” “change filters regularly”) to the subtle (“review piping infrastructure,” “reclaim compressed air for heating”).
At Plant Engineering, Atlas Copco Compressors’ Deepak Vetal offered four tips: Analyze air consumption, inspect distribution, reduce pressure and ensure that air receivers are property used. Care should be taken during inspection, he notes:
While some larger leaks can be heard in a system walk, an audit is the best way to ensure all leaks are found. Ultrasonic leak detectors are available to find minute leaks, but an ongoing identification program involving all personnel is the most effective practice.
Experts agree that great gains can be made in paying attention to a company’s compressed air platform. Bill Barnes, the Continuous Improvement Manager for Vac-Con, a truck-mounted machine manufacturer in Green Cove Springs, FL, wrote that neglecting compressed air issues is waste. “Air is really money,” he wrote in response to emailed question from Energy Manager Today. “Leaks are simply spending your company’s operational overhead with no value-added return.”
Information he sent suggested that compressed air generation may account for as much as 30 percent of the electricity certain types of businesses use.
Barnes wrote that the savings from adjusting unnecessarily high PSI settings is great. The differences plotted over the course of a year “may astound you,” he wrote. Managers should be wary of efforts of vendors and distributors efforts to sell more compressors. Beyond a certain point, adding PSI increases costs without increasing effectiveness. He adds that checking the integrity of piping is relatively simple.
One thing is very clear: Companies that use compressed air should carefully monitor their systems and keep them in perfect working order.