Three different quantities
kW measures active power; kVA measures apparent power. Power factor (PF) is their ratio. kW = kVA × PF; kVA = kW ÷ PF. Use PF as a decimal, such as 0.8.
Does 100 kVA mean 80 kW?
At a rated PF of 0.8, 100 kVA × 0.8 = 80 kW. This conditional example does not mean every load has a PF of 0.8. Stay within both the generator kW and kVA limits and confirm voltage, frequency and phases. A higher load PF does not permit exceeding the engine kW limit.
Motor nameplate kW needs another check
Motor nameplate kW often describes mechanical shaft output. For an illustrative 22 kW motor with 90% efficiency and PF 0.85, steady electrical input is about 22 ÷ 0.90 = 24.4 kW; apparent power is about 24.4 ÷ 0.85 = 28.8 kVA. These efficiency and PF values are examples: use actual manufacturer data. Starting demand is not included.
Send nameplates and a load list
Include input power or current, voltage, phases, PF, simultaneous operation and motor starting methods. Nonlinear loads such as variable-frequency drives and UPS units also require harmonic and generator compatibility checks.
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Technical reference: STAMFORD