Energy efficiency is more than picking the right motor

05 December 2008

High efficiency motors can save large amounts of electricity across industrial plants, but only if they are part of a system that has been carefully put together, according to Meinhard Schumacher, of SEW-Eurodrive. His company was displaying a comprehensive energy-saving concept called “effiDrive” at the SPS/IPC/Drives trade fair in Nürnberg in November 2008.

Meinhard Schumacher shows effiDrive example
Meinhard Schumacher shows effiDrive example

“It’s just like cooking,” he says. “You can have some great ingredients, but that doesn’t guarantee you’ll have a gourmet meal.”

Looking at fuel-efficient automobiles provides another readily understood example: a car company can design a very fuel efficient petrol or diesel engine, but if the transmission and drive gear is not properly matched, the efficiency may be lost in the inefficiency of the other components.

With the current developments in energy prices and electricity consumption, it is a logical consequence that SEW-Eurodrive would take a careful look at the energy saving process. It has defined its concept as consisting of three parts: energy saving-modules, energy consulting, and energy-efficient applications.

The company organises these building blocks—which may consist of some of its off-the-shelf motor and drive components such as the mechatronic drive system MOVIGEAR ® and the new DR-engine and modular MOVIDRIVE ® frequency inverter, as well as other components now in the development phase—into an energy efficient application solution.

energy efficient lift uses regenerative drives
energy efficient lift uses regenerative drives

“It is only through the intelligent and wise combination of engine, transmission, frequency converter and control from various energy efficient drive components that you get comprehensive energy-saving solutions,” says Mr. Schumacher. “Energy saving with the modular system thus leads to much better results than the individual optimisation of efficiency.”

The energy consultancy service is the central concept of energy saving in the system. The company maintains that, whether an existing or newly planned facility, the individual requirements of industry and application can be used only with a customer-specific advice to a genuine energy saving solution.


SEW-Eurodrive had on its stand at SPS/IPC/Drives three examples of the effiDrive concept.

automatic vehicle uses induced power
automatic vehicle uses induced power

There was a conveyor system that requires high torque to start, but once it has started, needs only medium torque for continuous operation. “Most applications of this sort use oversized motors to handle the high start up requirements which then waste electricity when in continuous operation,” says Mr. Schumacher, but engineers have devised a proper drive-motor-gear combination to resolve this energy efficiency issue.

Another part of the display demonstrated an energy efficient lift which uses regenerative drives to store energy as the drive goes down, to be used when it goes back up (middle photo). For complex applications of simultaneous motion in X and Y directions, a small PLC can make calculations that transfer energy from decelerating to accelerating components via a DC bus.

In a third example, an automatic vehicle travelled for several metres, following a cable embedded in the floor, which induced power to propel the motor. This saved having to put large and weighty batteries on the vehicle, which would eventually consume much more power (bottom photo).

Contact Details and Archive...

Related Articles...

Print this page | E-mail this page