gen-explain-power-factor-as-you-would-to-a-capable-student-in-3-400e

Explain power factor as you would to a capable student, in 3-4 sentences.

Power factor is the ratio of useful power (real power) that actually does work to the total power (apparent power) supplied to a circuit, ranging from 0 to 1. It arises in AC circuits because voltage and current can be out of phase—when they're perfectly aligned, power factor is 1 and energy transfer is most efficient, but reactive components like inductors and capacitors cause the current to lead or lag the voltage, reducing the power factor. A low power factor means you're drawing more current than necessary to deliver the same real power, which wastes energy in transmission and requires oversized equipment. That's why utilities often charge industrial customers penalties for poor power factor, incentivizing them to add compensation (like capacitor banks) to bring it closer to 1.