kVA ↔ kW
Convert apparent power (kVA) to real power (kW) and calculate power factor
0–1
Result
How does it work?
Real power (kW) is the actual useful power doing work (heat, motion, light).
Apparent power (kVA) is the total power the source must supply, including reactive power. kVA ≥ kW always.
Reactive power (kVAR) is the power that inductive/capacitive components borrow and return to the grid each cycle — it does no useful work but loads the conductors.
Power triangle: kW² + kVAR² = kVA². Therefore kVAR = √(kVA² − kW²).
Power factor: PF = kW / kVA. Typical range 0.8–0.95 for motors.
Example
Example: Generator rated 15 kVA, PF = 0.8.
→ Real power: 15 × 0.8 = 12 kW
→ Reactive power: √(15² − 12²) = 9 kVAR
To size a generator for a 10 kW load at PF 0.85:
→ kVA required: 10 / 0.85 = 11.76 kVA
Assumptions
- •Symmetrical single or three-phase loading
- •Sinusoidal voltage (harmonics not considered)
- •Power factor assumed constant