Utility & Power Quality
Distortion costs twice — as heat that does no work, and as a tariff penalty that usually dwarfs it.
— /yr
Extra losses plus tariff penalty
The penalty structure is entirely tariff-specific and must be taken from your own supply agreement — some utilities bill on voltage THD at the point of common coupling rather than current THD, some on reactive energy, and some not at all, so the threshold and rate here are placeholders rather than defaults. The loss coefficient is likewise a lumped fit that hides how losses depend on which harmonic orders dominate; the fifth and seventh are the usual offenders and drive transformer derating far more than the aggregate figure suggests. **Power quality remediation is electrical engineering work** — filter and reactor selection require a measured harmonic survey.
Spinning Mill Inverter Harmonic Distortion Power Penalty — free, with the formula and a worked example, at Textile School.