kW to kVAR Calculator
Calculate reactive and active power ratings with our free converter. Switch between kW to kVAR and kVAR to kW conversions instantly.
kW to kVAR Converter
How to Use the kW to kVAR Converter
Converting active power (kW) to reactive power (kVAR) is simple. Follow these steps:
- 1Enter Active Power (kW): Input your real power load.
- 2Enter Power Factor: Input the system efficiency factor (between 0.05 and 0.99).
- 3Click Calculate: Press the 'Calculate to kVAR' button to run the formulas.
How to Calculate kW to kVAR (Step-by-Step Guide)
To convert real active power in kW to reactive power in kVAR, evaluate the system power factor. The phase angle determines the ratio of imaginary power to real work. The formulas and mathematical workflow are presented below.
kW to kVAR Formula
Where:
- kVAR: Reactive power rating
- kW: Active power rating
- PF: Power factor (efficiency ratio)
Real-Life Scenario: Sizing Compensating Inductive Loads
An industrial ventilation motor draws 40 kW of real power at a power factor of 0.8. Sizing the required local capacitor bank compensation requires finding the reactive load:
- 1Find Phase Angle (θ):
θ = acos(0.8) ≈ 36.87° - 2Apply Formula:
kVAR = 40 × tan(36.87°)
kVAR = 40 × 0.75 = 30 kVAR
Final Output: The motor draws 30 kVAR of reactive power from the grid.
kW to kVAR Reference Conversion Chart
The table below outlines calculated reactive power values (kVAR) across various active power ratings (kW) at a standard 0.8 Power Factor (tan(acos(0.8)) = 0.75):
| Active Power (kW) | Calculated Reactive Power (kVAR) |
|---|---|
| 1 kW | 0.75 kVAR |
| 5 kW | 3.75 kVAR |
| 10 kW | 7.50 kVAR |
| 25 kW | 18.75 kVAR |
| 40 kW | 30.00 kVAR |
| 50 kW | 37.50 kVAR |
| 100 kW | 75.00 kVAR |
kW to kVAR Formula Three Phase
The standard kW to kVAR formula three phase relates active and reactive power in balanced AC systems. For balanced three-phase loads:
kVAR = kW × tan(acos(PF)).
Because active and reactive components scale equally, this single-phase ratio remains valid for three-phase systems.
100 kVAR to kW
Performing a 100 kVAR to kW calculation helps size real active loads. If a large industrial facility operates at a constant 0.8 power factor with a 100 kVAR reactive demand, the active power corresponds to:
kW = 100 ÷ tan(acos(0.8)) = 100 ÷ 0.75 = 133.33 kW.
50 kVAR to kW
Sizing the active load for a 50 kVAR to kW compensator operating at a 0.8 power factor helps estimate diesel generator load capacity:
kW = 50 ÷ tan(acos(0.8)) = 50 ÷ 0.75 = 66.67 kW.
kVA kW kVAR Formula
The relationship between apparent power, real power, and reactive power is defined by the standard kVA kW kVAR formula. These terms form the Power Triangle, expressed mathematically as:
kVA = √(kW² + kVAR²).
40 kW to kVAR
A load of 40 kW to kVAR at a 0.8 power factor has a reactive load calculated as:
kVAR = 40 × tan(acos(0.8)) = 40 × 0.75 = 30 kVAR.
This value helps determine the required reactive compensation rating.
Frequently Asked Questions (FAQs)
No. kW measures active power (real power that performs physical work), while kVAR measures reactive power (non-working power used to sustain magnetic fields in inductive loads).
To calculate the power factor (PF) from active and reactive power, use: PF = kW ÷ √(kW² + kVAR²).
Multiply 1 kW by the tangent of the phase angle: kVAR = 1 × tan(acos(PF)). At 0.8 power factor, 1 kW equals 0.75 kVAR.
No. kVAR is the unit of reactive power, while power factor is the dimensionless ratio of active power (kW) to apparent power (kVA).
One kilowatt of active power is calculated as: kW = kVA × PF or kW = kVAR ÷ tan(acos(PF)).
1,000 Watts is equal to exactly 1 kW, representing the base active power unit conversion.