Can a device use more wattage than it's rated for?

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K^2 said:
You think there is no capacitor at all to improve power factor? Seems kind of wasteful.
It isn't common because a single device with bad power factor isn't wasteful in and of itself. Residentially, you aren't charged for bad power factor and commercially it is cumulative for the meter, so if the overall isn't below .9 it doesn't matter what the individual devices are.
 
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It just seems like such an easy thing to fix for individual appliance that even the extra heating in the wiring between outlet and motor seems like a waste in comparison.

On the second point, though. The meter does charge based on RMS current, not power, doesn't it? Would it be at all practical to try and correct the power factor of the household? It'd have to be adaptive, of course, but the controller would be cheap. So long as capacitor banks required wouldn't be prohibitively expensive... I mean, we are talking 5-10% of the power bill here. That's not change.
 
Electric meters measure real power, not current. So a slight increase in amperage for something with very little resistance doesn't change the power enough to matter. It isn't like the manufacturer of the device is paying for the power anyway -- they'd rather pocket the extra $.50 per vacuum cleaner.

And adaptive power factor correctors -- commercial ones anyway -- are still pretty absurdly expensive.