Case 1
- Apparent power (kVA)
- 10kVA
- Power factor
- 0.8
8.00kW
Open with these valueskVA to kW Calculator
8.00kW
Result: 8.00 kWMultiply, do not divide: kW = kVA × PF. A 10 kVA generator feeding a load with a power factor of 0.8 delivers 8 kW of useful power. The power factor is the plain ratio from the nameplate, between 0 and 1, not an angle in degrees.
The numbers at a glance
Held fixed: Apparent power (kVA) 10.00 kVA.
| Power factor | Result (kW) |
|---|---|
| 0.60 | 6.00 |
| 0.70 | 7.00 |
| 0.80Your value | 8.00 |
| 0.90 | 9.00 |
| 1.00 | 10.00 |
Worked examples
Case 2
- Apparent power (kVA)
- 50kVA
- Power factor
- 0.9
45.00kW
Open with these valuesCase 3
- Apparent power (kVA)
- 25kVA
- Power factor
- 0.85
21.25kW
Open with these valuesHow it's calculated
kW = kVA × PF
- StepEnter the kVA rating from the generator, UPS or transformer nameplate.
- StepEnter the power factor of the load, between 0 and 1.
- ResultRead the real power in kW — the part that does useful work.
Reference table
| kVA, PF | Reactive power | Real power in kW |
|---|---|---|
| 10, 0.8 | 6.00 kVAR | 8.00 |
| 15, 0.95 | 4.68 kVAR | 14.25 |
| 25, 0.85 | 13.17 kVAR | 21.25 |
| 50, 0.9 | 21.79 kVAR | 45.00 |
| 100, 1 | 0.00 kVAR | 100.00 |
Questions
How do I convert kVA to kW?
Multiply the apparent power in kVA by the power factor. A 10 kVA generator with a power factor of 0.8 delivers 8 kW of real power. You will find the power factor on the equipment nameplate or data sheet.
What is power factor?
Power factor is the ratio of real power in kW to apparent power in kVA, and it says how efficiently a load turns supplied power into useful work. Purely resistive loads such as heaters and incandescent bulbs sit at 1. Motors and compressors typically fall between 0.7 and 0.95.
Why are generators and UPS units rated in kVA?
Apparent power determines the maximum current the windings and cables must carry, whatever the power factor of the load happens to be. The usable kW output depends on what is connected: a 10 kVA generator delivers 7 kW at a power factor of 0.7 and 10 kW at 1.
What is the reactive power in kVAR?
It is the part of the apparent power that oscillates between source and load without doing useful work, kVAR = kVA × √(1 − PF²). At 10 kVA and a power factor of 0.8 that is 6 kVAR. Correction capacitors reduce it and push the power factor toward 1.
Which power factor should I assume?
Take it from the nameplate whenever you can. Common reference values are 1 for resistive heaters, 0.9 to 0.95 for LED lighting, 0.85 to 0.95 for motors at full load and 0.6 to 0.8 for motors running part-loaded.
Sources and last check
Information, not professional advice.