Generator fuels
Fuel choice affects a generator’s supply arrangements, operating logistics, and available electrical rating. A fuel label describes the engine’s supported energy source; it does not by itself determine whether the generator is portable, permanently installed, or an inverter model.
In this topic
Natural gas generators
How natural gas generator systems work, what their fuel supply requires, and how to read their output ratings.
FuelsPropane generators
Understand propane storage, vapor delivery, fuel consumption, and generator capacity on liquid propane.
FuelsDual-fuel generators
What dual-fuel means, how fuel-specific ratings differ, and why switching behavior depends on the exact generator.
FuelsFuel type and generator output
Read fuel-specific running and starting ratings and distinguish output capacity from fuel consumption and runtime.
Explore the fuels
Natural gas generators use a methane-rich gaseous fuel, commonly delivered by a local gas utility. Propane systems rely on stored fuel and need sufficient usable inventory and delivery capacity. Dual-fuel generators support two specified fuels; the exact pair and switching behavior depend on the model. [1] [2]
These arrangements create different outage dependencies. A pipeline connection avoids routine tank refilling, while stored propane provides an on-site inventory that will eventually need replenishment. Neither arrangement establishes unlimited operating time: the generator still has service requirements.
Compare like with like
When comparing equipment, check the running and starting ratings on the fuel you will actually use. Also compare fuel-consumption figures at the same load and note their units. A gallon-per-hour figure and a cubic-foot-per-hour figure cannot be compared as equal quantities. The fuel-output article explains how to read these specifications without assuming a universal reduction between fuels. [3]
Sources and further reading
- EIA — Natural gas explained ↗www.eia.gov
- EIA — Propane basics ↗www.eia.gov
- Champion — Fuel-specific generator ratings ↗www.championpowerequipment.com
Use the manual and nameplate for the exact model. Local requirements and site conditions take precedence over general examples.