In electrical terms, a power factor of 1, often expressed as a power factor of 1.0, indicates that the voltage and current are in phase and that all the power supplied by the source is being used effectively for work. This means there is no reactive power in the system, only real power, and the system is as efficient as it can be regarding energy consumption. A power factor of 1 is typically the goal in AC (alternating current) power systems, as it represents the most efficient use of electrical power.
