Power Factor

Power factor is the ratio of real power (doing useful work) to apparent power drawn from the grid. A low power factor means current is wasted on reactive load, raising losses and often utility penalties. Correction with capacitors improves it.

Inductive loads such as motors and transformers draw reactive power that does no useful work but still loads cables and switchgear. A power factor below about 0.95 typically triggers utility surcharges and increases distribution losses. Power-factor correction equipment — capacitor banks or active correction — restores it close to unity, reducing demand charges and freeing electrical capacity.

Related terms

Energy Management System (EnMS / EMS) · Demand Response

Where this applies

Electrifying process heat · Installing power factor correction · Managing electrical peak demand