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Richard B
What is the relationship between power factor and electricity costs? View All
Is there any connection between a system's power factor and the amount of real power consumed by the system? If so, how is this related to the amount spent on electricity?

10 years ago - 8 months left to answer. - 1 response - Report Abuse
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sandeep murugesh
When the load is perfectly inductive current lags behind voltage by 90'.This makes the instantaneous power i.e the product of voltage and current(power) zero at specific places.Suppose if power of 1V and 1A at these instant it should have produce a power of 1W.But there is no power o/p at these places.Where does this power(negative power)go.Here inductor acts as source and power is transfered back to supply.This negative power will exactly cancel out with positive power giving a power dissipation of zero.That is Our 1W of input is not producing 1W of heat.This is called wattless watts. The correct term is Volt-Amps or VA. We say the circuit is drawing 1VA but consuming no power.The ratio of power to VA is called power factor.Clearly higher the pf lower is the power lost due to VA.So higher pf means less electricity costs.
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10 years ago

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