An example of four EC fans in parallel vs. four AC motors in parallel is shown on this slide. The AC motors were in on/off operation to reach 25%, 50%, 75%, and 100% of the airflow. The EC motors utilized the speed control capability to run all four fans at 25% to 100% speed. The electrical input power of the AC motors can be seen by the blue dots while the electrical input power of the EC motor can be seen by the green line. At 100% speed the power of both the AC motor and EC motor is fairly close, however as less airflow is required the EC motor is able to save up to 3 kW of electrical input power over the AC motor. This is illustrated by the yellow dashed line.