What term is used for the electric power transfer efficiency ratio?

The term that describes the electric power transfer efficiency ratio is indeed power factor. Power factor measures how effectively electrical power is being converted into useful work output and is defined as the ratio of real power flowing to the load, to the apparent power in the circuit. It is a dimensionless number between 0 and 1, or can be expressed as a percentage. A power factor of 1 (or 100%) indicates that all the energy supplied by the electricity utility is being used effectively for work, while a lower power factor indicates that some energy is wasted, often in the form of reactive power.

This concept is crucial in electrical systems to assess efficiency and reduce energy costs. Utilities often charge higher rates for customers with low power factors because it indicates inefficient use of power, leading to greater energy losses in the system. Higher efficiency in power transfer means better operation of equipment, which is essential for linemen to understand in their work to maintain infrastructure and deliver power effectively.