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Power Factor Correction

PRO

Capacitor Bank Sizing

Power Factor Correction is a Pro feature
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Application Presets

System Parameters

Poorcos φ = 0.70 (45.6°)
Excellentcos φ = 0.95 (18.2°)

Economic Analysis

Typical: $10-20/kVAR

Typical: $0.08-0.15/kWh

Capacitor Requirements

Required Capacitor Bank

69.15 kVAR
1524 μF

Power Factor Improvement

70%
Before
95%
After

Economic Benefits

kVA Reduction:37.6 kVA
Demand Charge Savings:$563.91/month
Energy Loss Savings:$145.47/month
Total Monthly Savings:$709.38
Yearly Savings:$8512.55

Return on Investment

Capacitor Cost:$1037.28
Installation Cost:$311.18
Total Investment:$1348.46
Payback Period:1.9 months✓ Excellent ROI

Calculation Steps

1. Real Power: 100 kW = 100000 W

2. Current power factor: 0.7 (70.0%)

3. Current reactive power (Q1): 100000 × tan(cos⁻¹(0.7)) = 102020.41 VAR

4. Target power factor: 0.95 (95.0%)

5. Target reactive power (Q2): 100000 × tan(cos⁻¹(0.95)) = 32868.41 VAR

6. Required capacitor: Qc = Q1 - Q2

7. Qc = 102.02 - 32.87 = 69.15 kVAR

8. Capacitance: C = Qc / (2π × f × V²)

9. C = 69151.99560415442 / (2π × 50 × 380²) = 1.524e-3 F

10. C = 1524.36 µF

11. kVA Reduction: 142.86 - 105.26 = 37.59 kVA

12. Improved power factor reduces utility demand charges!

Benefits of PF Correction

Reduce electricity demand charges (10-30% savings)
Lower I² R losses in cables (reduced heat)
Increase system capacity (can add more load)
Improve voltage regulation (less voltage drop)
Reduce transformer loading (extend equipment life)
Avoid utility penalties (many utilities charge for low PF)

Important Notes

• Do not over-correct (PF > 1.0 creates leading power factor issues)

• Use automatic PF controllers for variable loads

• Install harmonic filters if non-linear loads present

• Consider detuned capacitors for systems with VFDs

• Annual maintenance required (check capacitor condition)