Improving Motor Efficiency
May 22, 2012 - Contact FacilitiesNet Editorial Staff »
I'm Steve Schuster, associate editor of Maintenance Solutions magazine. Today's topic is motor efficiency.
Motors and the loads they drive represent some of the largest users of electricity in commercial and institutional facilities. Because motors are such high users of energy, they present a tremendous opportunity for maintenance and engineering managers to reduce energy use and cost through improved motor efficiency.
Much has happened recently that gives managers tools to improve motor efficiency. The federal government has developed energy standards that manufacturers must meet for the types of motors commonly found in a facility's energy-using systems. Replacing standard-efficiency motors with high-efficiency motors will reduce the energy requirements for that motor by about 2-8 percent. While that might not seem like a major improvement, depending on the horsepower of the motor and the number of hours it operates annually, the energy savings can be significant.
All of these energy-efficiency improvements come at a cost, however. The typical high-efficiency motor typically costs 10-15 percent more than the standard-efficiency motor it replaces. Premium-efficiency motors cost even more. But to help offset this increased cost and provide managers with the incentive to upgrade to more efficient motors, some utilities offer rebates and other incentives that can be as high as $50 per horsepower (hp).
Managers should evaluate their options based on the particular application. The amount of money they can save will depend not only on an improvement in operating efficiency but also on local utility rates and the annual number of hours of operation for that particular motor.