Calculate Required kVAR for Power Factor Correction | Capacitor Sizing
💡 Formula: kVAR = P × (tan(cos⁻¹(PF₁)) - tan(cos⁻¹(PF₂)))
kVAR Required = P × (tan θ₁ - tan θ₂)
📖 Capacitor Bank Size Calculator
This tool calculates the required capacitor bank size (kVAR) for power factor correction. Improving power factor reduces electricity bills, increases system capacity, and reduces losses. Enter load (kW), current PF, target PF, and voltage to get the required capacitor rating in kVAR and capacitance in µF.
📐 Capacitor Bank Formulas
Required kVAR: Qc = P × (tan(θ₁) - tan(θ₂)) Capacitance (µF): C = (Qc × 1000) / (2π × f × V²) Capacitor Current: Ic = Qc × 1000 / (√3 × V)
📊 PF Correction Benefits
PF Before
PF After
kVAR (100kW)
Savings
0.70
0.95
62.2
26%
0.75
0.95
49.4
21%
0.80
0.95
39.5
16%
0.85
0.95
29.7
12%
0.90
0.95
18.6
5%
📌 Standard Capacitor Bank Sizes
Small: 5, 10, 15, 20, 25 kVAR
Medium: 30, 40, 50, 60, 75 kVAR
Large: 100, 125, 150, 200, 250 kVAR
❓ Frequently Asked Questions
How to calculate capacitor bank size? ▼
kVAR = P × (tan(cos⁻¹(PF₁)) - tan(cos⁻¹(PF₂))). This calculator does it automatically.
What is power factor correction? ▼
Adding capacitors to offset inductive reactive power, reducing current, losses, and electricity bills.
What size capacitor for 100kW load? ▼
For 100kW at 0.80 to 0.95 PF, you need approximately 39.5 kVAR.
How to convert kVAR to µF? ▼
C (µF) = (kVAR × 1000) / (2π × f × V²). This calculator provides both values.
How much can I save with PF correction? ▼
Improving PF from 0.80 to 0.95 reduces current by about 16%.