System Assessments

A zinc producer spends an estimated \$516,000 annually on electricity to operate the air compressors in a compressed air system at its north American plant.  The current average electric rate, at this plant, is 5 cents per kWh, and the compressed air system operates 8,760 hours per year. This system assessment recommended a group of projects able to reduce these energy costs by fifty-one percent (51%) to an annualized \$270,000.  The simple payback of the project was 15 months – without taking into account potential incentive dollars from the local utility.

Great Plains has carved a global reputation for producing world-class seeding equipment since it first opened its doors in 1976. Great Plains manufactures a range of products from grain drills and planters, to compact drills and tillage equipment. They have established an international business built on expertise, knowledge and a commitment to producing products meeting the rigorous demands of the agricultural sector.

A meat processor, located in Canada, hired a consultant to assess their compressed air system as part of a company-wide energy conservation effort. The assessment and analysis showed, despite having a modern compressed air system using a VSD air compressor and pressure/flow control, the system was running inefficiently and had significant levels of leakage and inappropriate use.

While late summer may not be the time of year many of us think about heat recovery, the potential for energy savings in compressed air systems should be on our minds year-round. For those involved with the compressed air systems within International Wire Group’s facilities, energy savings is on their minds each day. This culture of continuous improvement has everyone on the lookout for savings wherever possible.

A steel distribution and processing company has upgraded and consolidated the compressed air systems in two of their distribution and processing facilities for big energy savings. The previous compressed air systems were running in modes of operation with very low efficiency. A complete replacement of the two systems with new air compressors and dryers has reduced the energy consumption significantly.

Load-sharing is an important part of a multiple centrifugal-compressor master control system. It minimizes blow-off based on the available turn-down. In addition, remote start-stop saves more energy if load floats between different ranges. Finally, adding a screw compressor and implementing a hybrid control system might save the most energy and provide the best back-up. In any case, a well-instrumented system allows engineers and operators to assess, optimize and tune the system.

An electronics manufacturer with a very large compressed air system recently had a compressed air audit done in their plant to assess system efficiency. The audit discovered the system had been designed to be extremely efficient, yet some previously undetected problems were causing less than optimal operation. Despite being located in a tropical environment, this plant utilizes heat recovery to help reduce the overall energy consumption.

This plant has three production lines producing snack food. Depending on the time of year and production demand the plant can operate anywhere from no production lines to all three production lines. A thorough supply and demand-side system assessment was done at this plant. This article will focus on some recommended demand-side reduction projects including nitrogen generation, air vibrators, leaks and vacuum venturis.

When a system has the right combination of VFD and base-load air compressors, how do you coordinate their control? What tells the air compressors to run and load, to have just enough (or no) base-load air compressors and a VFD running, all the time air is needed? Appropriate master controls are needed. These controls are often called “sequencers” or “master control systems”.

The company specializes in fabrication of precision assembled customized parts for OEM’s and system integrators. Since 1997 the company has steadily grown in size and capacity as the demand for its high quality fabrications has increased.  Through the years, many new CNC machines, laser cutters and powder coat painting operations have been added, but with all the expansion the facility has amazingly kept the plant compressed air consumption low. This has been achieved by following excellent “best practice” compressed air efficiency principles and by keeping watch on system waste.