Generator Fuel Consumption Calculator
Estimate generator fuel consumption, tank runtime, delivered electrical output, daily fuel use and operating cost from editable load assumptions.
Default project preview
0.65 gal/h
Electrical output
5 kW
Tank runtime
12.3 hours
Daily fuel
5.2 gal
Daily energy
40 kWh
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Estimated fuel rate interpolates between the entered no-load fraction and full-load fuel use. Runtime = usable tank ÷ hourly fuel rate. Output = rated kW × load percentage.
FAQ
Generator Fuel Consumption Calculator questions
Why does a generator still use fuel at low load?+
The engine must continue running and overcoming internal losses even when electrical demand is small.
Is fuel consumption linear with load?+
Not exactly. The interpolation is a planning estimate; manufacturer load-curve data is more accurate.
Can this calculate safe generator size?+
No. Starting loads, transfer equipment, grounding and installation require qualified electrical planning.