CDA Presents Motor Efficiency Paper at Association of Energy Engineers Conference
18 Mar 2016
By Richard E. deFay
Project Manager for the Copper Development Association’s Sustainable Energy Program
The Association of Energy Engineers (AEE) held their eastern regional conference, known as Globalcon, in Boston, Mass., March 9-11. Attendees included energy managers from industrial and commercial companies, students, Professionals Engineers (PE) and individuals from government and businesses representing every facet of the energy efficiency world. This included representation from the heating and cooling industry; producers of fans and testing equipment; wind, solar and energy management firms; and educational programs promoting energy efficiency.
There were more than 30 concurrent presentations at any one time throughout the conference. I was fortunate to have been selected to present a paper detailing the findings of CDA’s motor efficiency research conducted over the past several years. My colleagues and I presented a paper titled Efficiency Comparison between the Copper Rotor Motor and Permanent Magnet Motors. During the 9th International Conference on Energy Efficiency in Motor Driven Systems (EEMODS) held in Helsinki, Finland last year, we presented a paper detailing the findings of efficiency comparisons between a copper rotor motor (CRM) and three permanent magnet (PM) motors at 7.5 horsepower (HP). The results were encouraging enough to warrant continued research which this paper encompasses. The findings of this round of testing compared the efficiency of the copper rotor motor and three permanent magnet motors at 5 HP, 10 HP and 20 HP.
The presentation was well-received by the 29 individuals in attendance, who asked a variety of questions about the study’s findings. Although the efficiency results were not as stark as our initial test results, when product availability and simple payback were taken into account, the efficiency of the copper rotor motor shined by comparison. One principal we adhered to, was to keep confidential the names of the motors tested. Our objective was to neither embarrass nor promote any particular manufacturer, but rather to make an objective comparison of technologies. Motors selected for the study were procured through normal distribution channels with no effort to cherry pick motors to influence outcome. Some permanent magnet motors took 16 to 18 weeks to secure.
Because the permanent magnet motor requires a drive to operate and the copper rotor motor does not, it was determined that both should be tested using the drive recommended by the PM motor manufacturer. Adding a drive to the copper rotor motor actually reduces efficiency. We plan to complete another round of testing of the copper rotor motor without a drive to provide end-users a complete comparison for their buying decisions.
For more information on the efficient copper rotor motor, visit copper.org.