Compressed air systems have various cost components, ranging from miniscule to major. However, the most expensive measure in the total cost of compressed air is undoubtedly energy. Throughout the life span of a typical compressor, energy tends to cost several times more than the purchasing price of the air system. In order for industrial plants and facilities utilizing compressed air systems to get the most out of their unit, they must maximize the system’s energy efficiency.
Facility operators wanting to reduce the cost of their compressed air system’s energy usage should monitor and measure the system’s energy consumption, flow rates, and operating pressure. Small adjustments can make noticeable differences in reducing operating pressure and energy costs, thus improving flow rates and output. To assist employees in executing these measures, the Compressed Air and Gas Institute has released a list of 10 steps industrial facilities can take to optimize their compressed air systems and work toward energy efficiency.
- Turn the system off. Most compressed air systems only run at or near full capacity between 60 and 100 hours each week. Turning compressors off during evenings and weekends could reduce energy bills by 20 percent.
- Fix existing leaks. Pipe systems older than five years can have leaks of up to 25 percent. Because most air leaks are inaudible, it is important to employ third-party help in detecting system leaks.
- Prevent new leaks. Check inside your piping system. An optimal pipe is clean and dry with no corrosion issues. Dust and sludge clog filters and cause corrosion and should be fixed immediately following their discovery.
- Reduce pressure by not running beyond required pressures. Energy consumption is cut by one percent for each two psig reduction. A central supply side controller can greatly reduce the operational pressure band and orchestrate air production much more efficiently and effectively.
- Ensure condensate drains are not stuck open. Drains on timers should be regularly adjusted to ensure they open only as intended. If timed drains are found to continually waste compressed air, replace them with zero-loss drains.
- Review piping infrastructure for optimization. Pressure drops increase with increased flow through a pipe. Increasing the size of a pipe from two inches to three can reduce pressure drop up to 50 percent. Furthermore, shortening air travel distance can reduce pressure drops by up to 40 percent.
- Change filters systematically. Inspect and replace filters systematically to ensure air quality and prevent pressure drops. Systems operators should also regularly check and maintain air-line and point-of-use filters around their facility.
- Recover and reuse compressed air system heat. As much as 90 percent of heat given off in compressing air can be recovered for reuse, such as to hear water or direct warm air in a workspace.
- Emphasize proper maintenance. Proper compressor maintenance cuts energy costs by around one percent and helps prevent breakdowns that result in downtime and lost production.
- Identify and eliminate inappropriate uses of compressed air. Inappropriate compressed air uses include any application that can be done more effectively or efficiently by a method other than compressed air.