Power factor is a ratio of real power to apparent power. Real power, typically measured in Kilowatts (kW), is the amount of power needed to operate a piece of equipment. Apparent power, measured in kilovolt-amps (kVA), is the amout of power present in the circuit to keep it energized. These may diverge when used to power inductive loads, such as refrigeration compressors or other large electrical motors. Poor power factor can waste significant amounts of energy and overburden electrical infrastructure.