What size capacitor bank for 100kW load?

For 100kW at 0.80 to 0.95 PF, you need approximately 39.5 kVAR.

kVAR vs µF - what's the difference?

kVAR is reactive power rating. µF is capacitance value. Both describe the same capacitor.

How much can I save with PF correction?

Improving PF from 0.80 to 0.95 reduces current by about 16%, saving energy and reducing utility penalties.

Capacitor Bank Size Calculator | kVAR Correction | Power Factor Improvement

📖 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) (3-phase)

Where:
P = Load (kW) θ₁ = cos⁻¹(PF₁) θ₂ = cos⁻¹(PF₂)
f = Frequency (Hz) V = Line Voltage (V)

📊 Power Factor Correction Benefits

PF Before	PF After	kVAR Required (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
Heavy: 300, 400, 500, 600, 750 kVAR
Always select the next standard size above calculated value

💡 Capacitor Bank Connection Types

Star (Wye) Connection: Capacitors connected between phase and neutral. Voltage = V_phase = V_line / √3
Delta Connection: Capacitors connected between phases. Voltage = V_line
Delta connection gives higher kVAR for the same capacitance value
Most capacitor banks are delta-connected for higher rating

🔧 How to Use This Calculator

Enter load (kW) - total active power of the system
Enter current PF - existing power factor (e.g., 0.80)
Enter target PF - desired power factor (e.g., 0.95)
Enter system voltage (V) - line voltage
Select frequency - 50Hz or 60Hz
Results include required kVAR, capacitance in µF, and capacitor current

❓ Frequently Asked Questions (FAQ)

❓ How to calculate capacitor bank size? ▼

kVAR = P × (tan(cos⁻¹(PF₁)) - tan(cos⁻¹(PF₂))). This calculator does this automatically for you.

❓ What is power factor correction? ▼

Power factor correction is the process of improving PF by adding capacitors to offset inductive reactive power. This reduces current, losses, and electricity bills.

❓ What size capacitor bank do I need for 100kW load? ▼

For 100kW at 0.80 PF to 0.95 PF, you need approximately 39.5 kVAR. Use the next standard size (40 kVAR or 50 kVAR).

❓ How to convert kVAR to µF? ▼

C (µF) = (kVAR × 1000) / (2π × f × V²). This calculator provides both kVAR and µF values.

❓ What is the difference between kVAR and µF? ▼

kVAR is the reactive power rating of the capacitor bank. µF is the capacitance value. Both describe the same capacitor from different perspectives.

❓ How much can I save with power factor correction? ▼

Improving PF from 0.80 to 0.95 reduces current by about 16%, which translates to similar savings in losses and potentially lower electricity bills if your utility charges PF penalties.