How is frequency inverter saving energy?

Energy saving using frequency inverter is always vary application to application. Following points you need to consider before using frequency inverter for energy saving.

1. How much process flow and pressure requirement through AC motors
2. Existing control methodology like control valve in pumps, Damper or guide vane for Fans & Blowers etc. and position of the valve or dampers
3. If you have process flow and pressure data and pump or fan design data, you can calculate energy saving using affinity law
4. Loading and Unloading cycle for compressor application. If the unloading time is higher for compressor application, you will get better energy saving
5. Using affinity law, you can calculate the energy saving with consideration of frequency inverter losses. With this you can calculate the Pay back of the inverters.
There are different ways you can use frequency inverter or soft starter to reduce your energy bill. Carefully analyses the possibilities of your plant.

For example, if you have a blower/ ID fan/ pump etc., you may run the motor full speed and adjust the suction or flow using a valve. But you run the motor full speed (consumes total energy) even you need less work from the motor. So for that application you can use a frequency inverter where you can reduce the motor speed to reduce suction or flow instead of closing vale. This will help you to use only required amount of energy for your application. This will reduce the power consumption of the motor.

Also if you use soft starters with your motor it will start the motor with less starting current, where it will help to bring down your maximum demand of utility bill.