Power Factor Correction Calculator

Optimize electrical efficiency and reduce energy costs

Power Factor Correction Calculator

IEEE 519 & IEC 61000 Standards Compliant

Enter as decimal (e.g., 0.85 for 85%)
Recommended: 0.95 (95%)

Correction Results:

Required Capacitors

Reactive Power: 0.00 kVAR

Capacitance: 0.00 μF

Current Analysis

Before Correction: 0.00 A

After Correction: 0.00 A

Current Reduction: 0.00%

Power Analysis

Apparent Power Before: 0.00 kVA

Apparent Power After: 0.00 kVA

kVA Reduction: 0.00%

Annual Savings

Energy Savings: $0.00

Demand Savings: $0.00

Total Annual Savings: $0.00

Power Factor Penalty Calculator
Power Factor Triangle Calculator

How to Use the Power Factor Correction Calculator

Step 1: System Information

  1. Select your system type (Single or Three Phase)
  2. Enter the real power consumption in kW
  3. Input the system voltage (line-to-line for 3-phase)
  4. Choose your system frequency (50Hz or 60Hz)

Tip: Use nameplate data or measured values for accuracy

Step 2: Power Factor Data

  1. Enter current power factor as decimal (0.75 = 75%)
  2. Set target power factor (typically 0.95)
  3. Input energy and demand charges from utility bill
  4. Click "Calculate" to get results

Note: Most utilities require PF ≥ 0.90 to avoid penalties

Step 3: Understanding Results

  • kVAR: Required capacitive reactive power
  • Capacitance: Total capacitor size needed
  • Current Reduction: Decrease in line current
  • Savings: Annual cost reduction potential

Important: Consider installation costs vs. savings

How Power Factor Correction Works

Power Factor Fundamentals

Power Factor (PF) = Real Power (kW) / Apparent Power (kVA)

Power factor represents the efficiency of electrical power usage. A low power factor means more current is required to deliver the same amount of useful power, resulting in:

  • Higher electrical losses
  • Increased utility demand charges
  • Reduced system capacity
  • Voltage regulation problems

Capacitive Correction

Capacitors provide leading reactive power to offset lagging reactive power from inductive loads:

  • Motors and transformers create lagging power factor
  • Capacitors create leading power factor
  • Proper sizing neutralizes reactive power
  • Result: Improved overall power factor

Detailed Calculation Example

Example: Industrial Motor Load

• Real Power: 100 kW

• Current Power Factor: 0.75

• Target Power Factor: 0.95

• System: 480V, 3-phase, 60Hz

Step 1: Calculate Current Reactive Power

θ₁ = arccos(0.75) = 41.41°

Q₁ = P × tan(θ₁) = 100 × tan(41.41°) = 88.19 kVAR

Step 2: Calculate Target Reactive Power

θ₂ = arccos(0.95) = 18.19°

Q₂ = P × tan(θ₂) = 100 × tan(18.19°) = 32.87 kVAR

Step 3: Required Capacitor Size

Qc = Q₁ - Q₂ = 88.19 - 32.87 = 55.32 kVAR

Step 4: Capacitance Calculation

C = Qc × 10⁶ / (2π × f × V²)

C = 55,320 × 10⁶ / (2π × 60 × 480²) = 638 μF

Power Factor Correction Formulas

Power Factor:
PF = cos(θ) = P / S

Required Capacitive Reactive Power:
Qc = P × (tan(θ₁) - tan(θ₂))

Capacitance (Single Phase):
C = Qc × 10⁶ / (2π × f × V²)

Capacitance (Three Phase):
C = Qc × 10⁶ / (3 × 2π × f × V²)

Current Reduction:
I₂ = I₁ × (PF₁ / PF₂)

Power Factor Reference Table

Power Factor Angle (θ) tan(θ) Efficiency Rating
1.00 0° 0.00 Excellent
0.95 18.2° 0.33 Very Good
0.90 25.8° 0.48 Good
0.85 31.8° 0.62 Fair
0.80 36.9° 0.75 Poor
0.70 45.6° 1.02 Very Poor

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