Power Factor from Real and Apparent Power
Also known as PF · kW over kVA
Worked example: 8 kW out of 10 kVA → PF 0.8 — press Try an example to run it live, then adjust anything.
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Power Factor from Real and Apparent Power explained
Power factor is an efficiency of delivery, not of conversion: it says how much of the capacity you rented from the utility is producing work. A load reading 8 kW on the wattmeter but 10 kVA on the volt-amp meter runs at PF = 0.8, meaning a fifth of the supplied capacity is sloshing back and forth building magnetic fields instead of turning shafts. Both fields here are watt fields; enter kVA in the kW box, since VA and W are the same dimension.
Utilities care because that reactive current still heats their conductors and transformers, so large customers face a power-factor penalty — often triggered below 0.9 or 0.95. Lightly loaded induction motors are the usual culprit, drifting to 0.3–0.5 PF at no load; the standard cures are capacitor banks and, better, not oversizing motors in the first place.
Power Factor from Real and Apparent Power formula
- = Power factor
- = Real power (W)
- = Apparent power (VA) (W)
Missing one of these? Work it out first, then come back
- Power factor — Three-Phase Real Power, Single-Phase Real Power with Power Factor
- Real power — Three-Phase Real Power, Single-Phase Real Power with Power Factor
- Apparent power (VA) — Three-Phase Apparent Power, Reactive Power (Power Triangle)