Electronically Commutated (EC) fans are AC input fans that utilize a brushless DC motor. EC fans incorporate a voltage transformation within the motor that converts the incoming AC power to DC voltage. EC fan motors use permanent magnets to generate a secondary magnetic field rather than traditional copper windings used in AC motors. The increased efficiency of the brushless DC motor means that less energy is lost as heat, while more energy is turned into rotational force and therefore more cooling power. This is why EC fans are able to deliver significant energy savings compared to standard AC fans.