### What is Power Factor?

The power factor of an AC electrical power system is defined as the ratio of the real power flowing to the load, to the apparent or total power in the circuit, and is a dimensionless number between 0 and 1. Real power [W] is the capacity of the circuit for performing work in a particular time.

In an electric power system, a load with a low power factor draws more current than a load with a high power factor for the same amount of useful power transferred. The higher currents increase the energy lost in the distribution system, and require larger wires and other equipment. Because of the costs of larger equipment and wasted energy, electrical utilities will usually charge a higher cost to industrial or commercial customers where there is a low power factor.

For a full list of terms related to power factor correction, please visit our glossary of terms.