What Is Power Factor Correction?

A practical explanation of how PFC reduces reactive power charges, improves efficiency and lowers your electricity costs.

Understanding Power Factor

In simple terms, power factor is a measure of how efficiently your electrical system uses the power supplied by the grid. Industrial sites with motors, compressors, welders or HVAC equipment often draw more power than they actually use. This wasted energy is known as reactive power, and the utility charges you for it.

Power Factor Correction (PFC) reduces this wasted energy by installing capacitors or automatic systems that balance the electrical load. The result is lower bills, fewer penalties and a more efficient network.

How Power Factor Works

Below is a simplified representation of real power, reactive power and apparent power:

Real Power (kW)
Reactive Power (kVAr)
Apparent Power (kVA)

Power Factor = kW ÷ kVA. Improving power factor reduces the kVAr component, lowering your overall demand.

Why Power Factor Correction Matters

Lower electricity bills
Reduce reactive power penalties
Improve transformer & cable efficiency
Reduce voltage drop & heat
Extend equipment lifespan
Fast ROI (often under 12 months)

Types of Power Factor Correction

Fixed PFC

Simple capacitor banks used for steady loads such as pumps or fans.

Automatic PFC

Multi‑step systems that adjust to changing load conditions using contactors or thyristors.

Detuned / Filtered PFC

Used where harmonics are present. Protects capacitors and prevents resonance issues.

Real-Time PFC

Static VAr Generators (SVG) respond to load changes within milliseconds, ideal for rapidly varying loads. Where high harmonic distortion is present, Active Power Filters (APF) cancel harmonic currents in real time without the resonance risk of passive capacitor banks.

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