Generator Sizing Calculator

Calculate generator kVA rating, fuel consumption, and load capacity for standby and prime power applications.

Sum of all connected loads.
kW
Average power factor of connected loads.
Not all loads run at once. Typical: 0.6-0.8.
Allowance for load growth. 1.0 = none, 1.25 = 25%.
Altitude, temperature derating. Typical: 1.1-1.3.

Results

Effective Load-kW
Required Generator Rating-kVA
Generator kW Rating-kW
Est. Fuel Consumption-L/h
References: ISO 8528 — Generator Sets; NFPA 110