Did you know that factories, hospitals, schools and other buildings are full of fans that contribute a significant portion to the electricity bill?
Fan systems are responsible for approximately 10% of the electricity consumption in the industrial and municipal sectors. Variable speed drives (VSDs) are used in fans and blowers to control the flow of air. VSDs reduce the electric motor input power instead of causing additional losses, thus reducing the electricity consumption of the electric motors driving the application.
ABB works together with numerous universities and organizations around the world on various types of research projects. For instance, here in Finland our collaboration partner, the Lappeenranta University of Technology (LUT) is working on several research projects to optimize the energy consumption and life cycle costs of pumps, fans, compressors and conveyors. A few years ago I researched the use of VSDs in fan system monitoring as part of my doctoral thesis at the LUT.
I’d like to share with you my top 5 tips to ensure that the electricity consumption of your fan application is optimized:
- The direction of rotation is a very important factor. If the fan rotates in the wrong direction, the efficiency is often poor. This can be checked after the installation and maintenance – soon automatically.
- Let your imagination guide what could be done to improve the fan systems and do not settle on what has been proven to work. The use of new methods in the control of the fans systems will develop the technology faster. In case of emergency, you can always go back to the old system.
- Simply turn off the fan when it is not needed.
- Lose the former setup, if the new ones take their place. If rotational speed control is installed, the damper in the same duct can be safely left open. Every now and then we see systems where a damper is left half-closed as standard setting in front of the fan equipped with rotational speed control. In this case, there are two methods providing the same control, the other one is only producing losses.
- Torque and mechanical stress go hand in hand. If you feel that the fan does not run smoothly, then it is worth checking if there’s something wrong.
Usually, the fan system operation is optimized based on measurements by various meters used in the system, adding to the system complexity. In addition to improving the energy efficiency, VSDs can also be used to monitor the condition of fan systems as well, enhancing the overall efficiency of fan systems without additional measurements.
By using VSD control and saving in electricity, equipment and maintenance costs, life cycle costs of a fan system can be reduced significantly while improving its reliability at the same time.