Use the correct burn rate
Generator fuel consumption is not a single fixed number. A unit at half load normally burns less than the same unit at full load. Find the table for your exact model, fuel, and expected load, then enter that hourly rate above.
Propane tank reality: a nominal 500-gallon tank is not treated as 500 usable gallons. This calculator’s reserve setting lets you plan around fill limits and a safety margin.
What this estimate does not replace
Fuel-system sizing, regulator capacity, pipe sizing, electrical load calculations, transfer equipment, and installation should be verified by qualified professionals. This tool is for planning outages and comparing scenarios.
Method: hourly burn rate × runtime. Use model-specific manufacturer data. Estimates vary with actual electrical load and operating conditions.