Electric motors with improved efficiency, in combination with frequency converters can save about 7% of the total worldwide electrical energy. Roughly one quarter to one third of these savings come from the improved efficiency of the motor.
Motors from 0.37kW to 375kW make up the vast majority (approximately 90%) of installed population and are covered by the standard IS 12615:2011. This fulfills the need of the manufacturers to design motor for a global market. This standard defines four efficiency classes for nominal frequency 50Hz.