Posted: March 12, 2014
Kaeser: blog for the compressed air user
Source: Susan Hodges, System Design Engineer, Kaeser Compressors, Inc.
The purchase price of a compressor is an important consideration when comparing new equipment options, but it’s only one of several cost components that affect the overall cost of owning and operating an air system. Low price options often have higher life cycle costs.
Installation, energy, maintenance and repair, as well as lost time and materials each greatly impact the overall bottom line of your compressed air system. Be sure to consider each of these other cost drivers as you are making a purchasing decision. In many cases, the benefits in one area outweigh the costs in another and vice versa.
Installation: The equipment you select directly impacts installation costs. It’s common for buyers to build separate rooms or structures to isolate noisy, vibrating compressors from employees and customers for the sake of safety and comfort. When selecting equipment, it is always a good idea to review the sound pressure level, general environmental requirements, such as air intake and discharge, and general electrical requirements of the equipment. Choices in piping also impact installation time and labor.
Energy: Compressors are by nature energy intensive. Your energy costs depend on the compressor size (hp), how much you run it, and your local utility rates, but even small compressors are often the largest energy user in a shop. Compressor efficiency varies widely between types and brands of compressors, so there are opportunities for significant savings. One major source for savings that is often overlooked is recovering the heat generated by the compressor—even for small compressors. Since 100% of the electrical energy used by the compressor is converted into heat and 96% of this energy is available for recovery, the savings potential with heat recovery is huge.
Maintenance and repair: Be sure you understand the preventive maintenance as well as periodic major maintenance requirements of equipment you are comparing. Also, system sizing and installation location impact the duty cycle and heat load on the compressor. These factors heavily influence longevity.
Lost time and materials: Often overlooked (because they are harder to calculate) are the costs of lost productivity due to downtime as well as wasted time/materials and reduced tool life due to poor air quality or fluctuating pressure. These may be among the highest costs associated with compressed air, and they can quickly erase the savings gained during the equipment purchase.
For more information and energy saving tips, visit Kaeser’s sustainability page.