The inventor of EC technology, Gert Haeussermann, coined a phrase when it was first introduced to try to allay fears over the new technology. He often said “EC is easy” to counter the fear of the perceived complexity of the then new technology.
In recent years this phrase has taken on a new meaning, as many believe that EC is the easy way to meet the requirements of the EU’s Ecodesign of Energy-related Products (ErP) Directive for fans. This, however, masks other solutions and innovations as great alternatives to meet the ever-rising challenge for higher efficiency fans.
Changing the motor of a fan from a low efficient AC motor to an EC motor is a simple way to increase the overall efficiency of the fan, especially if the motor is an external rotor motor. Modern EC technology is often so small that it fits in the same space as the old AC motor.
More than motors
However, fan manufacturers are doing a lot more than just changing the motor.
EC technology is not new and has been an established motor technology for over 10 years. It is undeserved to think that the fan industry has done nothing else ever since. Millions of euros are invested each year in all aspects of fan technology, not just that focused on motors. The industry continually develops ever more energy-efficient fans.
Today’s investments are moving aerodynamic research beyond textbook design. Impellers are no longer designed using standard rules. Now, they are developed using computational fluid dynamics (CFD) and then those models are challenged using empirical analysis by tracking flow trajectory of individual molecules of air through the fan using lasers. The data from this analysis is then used to adapt the theoretical CFD ever closer to reality.
This gives the R&D team the ability to think radically and investigate their new ideas with ever more reliable computational tools before production.
So what about EC technology? It is the icing on the cake that adds to the success of the large investment in fan aerodynamics and, in many ways, EC is an easy solution.
However, the industry is not relying on just this one solution, and will continue to innovate fan technology and strive for even greater energy efficiency.
Geoff Lockwood is technical director at ebm-papst