Report current and voltage out of phase in Theory articles Posted April 5, 2007 Does current that is out of phase with voltage mean lower available power. I see inductors used everywhere in power supplies, but are they used for more than ripple reduction?It is all about the Power Triangle. So the answer is, it depends on what you mean by power. If the current and voltage are in phase, all of the power will be "real" so real power = apparent power or KW = KVA.If there is an inductor or a capacitor in the circuit, the voltage and current will be out of phase, therefore the real power will be the same but there will be a component of "active" power which has a phasor +/- 90 degrees out of phase with the real power. When you determine the "apparent Power" it will now be more than the "real" power or KVA>KWThe long story short is study the power triangle.Audioguru, there are many types of AC power supplies, what about a UPS or a VFD?