what is power factor in electricity?
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Don’t think I can do this unless the 5yo understands basic trign functions.
You know voltage is measured in volts, and current is measured in amps. Well, power is measured in watts.
A watt is a volt multiplied by an amp.
So, to get the power drawn by a device, you multiply the voltage by the current it draws. This gives you the power it is drawing.
Except that it doesn’t really, particularly with alternating current.
The simplistic amps x voltage works if the load behaves more or less like a simple resistor, but mant loads aren’t
If we’re talking about an AC motor, it’s coils will act like an inductor, which will cause the current to be out of phase with the voltage. Thus a simple multiply becomes a complicated trign expression with a ‘phase difference’ between two sine waves.
If we’re talking about a modern switch-mode power supply, we get the opposite problem because the load now looks like a big capacitor.
So power factor is a measure of the difference between the current and voltage phases. Some energy companies bill differently according to power factor, as it affects where the waste heat energy is dumped and how hard the generators have to work.
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