Power factor converter
Convert power factor into the phase angle behind it, and into the kVA a hundred kilowatts of real load would draw.
That's 1.14× as good as a half-loaded motor, while a fully loaded motor is 1.06× better. A 100 kW load at that factor draws 125 kVA.
What it means
How much is wasted?
This is displacement power factor, for clean sine waves. Electronic loads add harmonics, and their true power factor is worse than the phase angle suggests.
Every unit
Your power factor in every unit
Learn
Three things worth knowing
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kVA = kW ÷ power factor
A 100 kW load at 0.8 needs 125 kVA of supply. Correcting it to 0.95 brings that down to 105.
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Reactive power does no work
It flows out to the magnetic field and back, twice per cycle, doing nothing but heating the cables on the way. Capacitors correct it by supplying it locally.
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Power factor is not efficiency
A motor can be 95% efficient and have a power factor of 0.7. Efficiency is about energy lost; power factor is about current carried.
Shortcuts
Popular power factor conversions
Background
About power factor
In an AC circuit with a motor or a transformer, current lags voltage. The power factor is the cosine of that lag, and it says what fraction of the current is doing real work.
At 0.8, a 100 kW load draws 125 kVA — a quarter more current, and a quarter more cable, for the same work. That is why industrial tariffs penalize it.