Power Factor Correction
Most recent answer: 04/15/2011
Q:
Will reducing current with power factor correction lower my residental electric bill.
How about my commercial electric bill?
- Dennis (age 60)
Oaklyn, NJ 08107
- Dennis (age 60)
Oaklyn, NJ 08107
A:
I should explain first for other readers what power factor correction is. The power drawn by an electrical circuit is the product VI of the voltage and the current. For an ac circuit, both V and I of course oscillate over time (t) so the average product over time is not the same as the product of the averages of V(t) and I(t). (The averages of V and I are each zero.) If the load is purely resistive, V(t) and I(t) are just proportional: I=V/R, so the average of VI is just the square root of (the average of V2 times the average of I2).
There's a nice Wikipedia article on all this, going into further complications such as non-linear loads.
According to Consumer Reports, the electric companies meters actually measure power, not just current. So I don't think you could save anything at home.
Apparently there's some expense involved in making and distributing the larger currents required for a given power when the power factor is less than one. The electric companies charge commercial users more for per watt when the power factor is much less than one. So maybe you could save money in a commercial use by getting a device that adjusts the load to give a power factor near one.
Mike W.
There's a nice Wikipedia article on all this, going into further complications such as non-linear loads.
According to Consumer Reports, the electric companies meters actually measure power, not just current. So I don't think you could save anything at home.
Apparently there's some expense involved in making and distributing the larger currents required for a given power when the power factor is less than one. The electric companies charge commercial users more for per watt when the power factor is much less than one. So maybe you could save money in a commercial use by getting a device that adjusts the load to give a power factor near one.
Mike W.
(published on 04/15/2011)