Several years ago, Arthur D. Little & Associates did a study and determined that approximately 64% of the energy consumed in the USA was consumed by industry. Most of this energy is used to power electric motors that turn the wheels of industry. Industrial electric motors are everywhere, powering fans, blowers, pumps, and conveyors of all kinds.
Industrial users, hit by many economic factors in the past several years, are looking for ways to cut their costs, particularly energy-related costs. Also, due to power shortages, peak demand charges, energy efficiency is becoming a blossoming concern.
Energy use by electric motors did not go unnoticed by the federal government. In 1992, Congress passed the Energy Policy Act of 1992 (EPAct). It was put into effect in October of 1997. Basically, most industrial motors from 1-200 hp were required to meet minimum operating efficiencies. It became illegal to build anything but an EPAct motor. This law did a lot to improve the awareness and application of more efficient motors.
Most recently, the NEMA organization has defined the requirements of the next step up in efficiency (not a law), called NEMA Premium™. Utilizing NEMA Premium motors has several benefits for the industrial user:
- Improved efficiency resulting in lower operating costs
- Lower noise
- Cooler running
- Longer life.
The advantage to the USA is lower energy consumption that results in less demand on our "taxed" power distribution system. In addition to NEMA Premium motors, coupling them to adjustable speed drives (ASDs) greatly reduces energy consumption and adds life to motors and their driven loads (pumps, compressors, etc.). It also improves process control and the overall efficiency and the reliability of the processes they power.
Finding ways to improve the efficiency of electric motors is becoming more difficult, but new materials, manufacturing techniques, and technologies are still evolving. A few recent achievements include improved winding equipment, winding insulation systems, magnetic bearings, better electrical grade steel and die cast copper rotors.
Help for the uninformed industrial user interested in saving energy and improving efficiency is not hard to find. A nonprofit organization comprised of utilities, motor manufacturers, EASA, NEMA, the DOE and other interested parties called "Motor Decisions Matter" (www.motorsmatter.org) has the charter to promote the NEMA Premium line of motors. They have links to motor management and payback software that's real easy to use. They have coupled their resources with NEMA to promote NEMA Premium motors.
