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Power Factor Correction — Capacitor Bank Sizing | Engineering Database

Power Factor Correction — Capacitor Bank Sizing

electrical

Sizes capacitor banks for power factor correction. Calculates required kVAR, selects standard capacitor bank size, and determines current reduction and optional annual savings from PF penalty elimination.

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Load Kw*

Total real power of the load in kilowatts. Obtain from metered demand or sum of connected equipment ratings. Total real power of the load or facility. Typical: 50-500 kW commercial, 500-5000 kW industrial.

Current Pf*

Existing (uncorrected) power factor of the load, expressed as a decimal. Read from utility bill or power meter. Must be less than target_pf. Typical uncorrected: 0.70-0.85 for motor-heavy loads, 0.85-0.95 for mixed.

Target Pf

Desired corrected power factor. Most utilities require 0.90-0.95 to avoid penalties. Unity (1.0) is theoretically possible but rarely targeted. If omitted, defaults to 0.95.

Voltage

System line voltage in volts where the capacitor bank will be installed. Common values: 208, 240, 480, 600, 4160. If omitted, defaults to 480 V.

Phases

Number of phases. Use 3 for three-phase systems (most industrial) or 1 for single-phase. If omitted, defaults to 3 (three-phase).

Penalty Rate Per Kwh

Utility reactive power penalty rate in USD per kVAR-hour, if applicable. Used to estimate annual savings from PF correction. If omitted, annual savings calculation is skipped.

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Reference data

This calculator pulls live values from the following engineering reference tables in the database.

pf correction

About this calculator

Power Factor Correction — Capacitor Bank Sizing is part of the Engineering Database calculator suite. Each tool runs deterministic calculations against authoritative reference data and code-compliant methods, so results are reproducible and traceable to source standards.

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