Power Factor of a Capacitor

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Simplified, KW = KVA cos φ, where φ is the angular difference in phase between voltage and current, and where cos φ is also called "power factor".

Resistive loads have 1.0 power factor (φ = 0);
Inductive loads (induction motors, solenoids, etc.) have lagging power factor < 1.0.;
Capacitive loads have leading power factor, also < 1.0.

The power factor of a perfect capacitor is 0.