Utility & Power Quality
The penalty is the visible saving. The transformer capacity you get back is often the larger one.
— kvar
To move from existing to target power factor
Correcting to unity is the wrong target and a genuine hazard: a lightly loaded system with fixed capacitors can go leading, which some tariffs penalise as heavily as lagging and which can excite resonance with supply inductance. Target 0.95 to 0.97 and use automatic switched stages so correction follows load. **Capacitors and harmonics interact badly** — in a plant with significant drive harmonics, plain capacitors can form a resonant circuit with the supply and amplify distortion rather than help, so detuned reactors are usually mandatory alongside them. Size and specify with a measured load and harmonic survey by a qualified electrical engineer.
Loom Motor Power Factor Correction Capacitor Calculator — free, with the formula and a worked example, at Textile School.