In propulsion motor data, what is the term for the measure of an electric motor's output efficiency?

The measure of an electric motor's output efficiency is known as thermal efficiency. Thermal efficiency refers to the ratio of useful work output to the total energy input, considering how much of the electrical energy is converted into mechanical energy versus lost as heat. This metric is crucial when evaluating the overall performance of a propulsion motor, as it determines how effectively it converts electrical energy into motion.

While regeneration performance relates to how well a motor can recapture energy (like during braking in electric vehicles), it does not directly measure efficiency. Power factor describes how effectively electrical power is being converted into usable work output but doesn’t provide a direct measure of output efficiency as thermal efficiency does. Torque is a measure of rotational force and indicates how much rotational power a motor produces, but it does not quantify efficiency. Thus, thermal efficiency is the accurate term used for expressing an electric motor's output efficiency.