Fuel choices and dual fuel

What is dual fuel generator

Blank spiral notebook and tape measure on open gravel.

The short answer

What is dual fuel generator? A dual fuel generator runs on either of two fuels. On the listed models, those fuels are gasoline and propane. That gives you fuel flexibility. For these models, running watts on propane are lower than on gasoline. Before you rely on any number, read the exact model's specifications and manual.

Last updated October 2026

What's covered5

A dual fuel generator is an engine generator that can use either of two fuels. Many shoppers see the label and wonder what it changes. This guide explains the term using maker specifications.

A dual fuel generator is an engine generator built to run on two fuels. The models listed here use gasoline and propane. Rated output can change with the fuel. On the Westinghouse iGen2550DFc, running watts drop from 1900 on gasoline to 1700 on propane. The steps for switching fuels come from each model's manual, not from a general rule.

Model Type Gasoline running W Propane running W Natural gas running W Voltage
Westinghouse iGen2550DFc Dual fuel inverter 1900 1700 Not listed 120 V
Champion 201278 Dual fuel inverter 3500 3150 Not listed 120 V
Champion 201176 Tri-fuel inverter 7250 6525 5875 120/240 V
Westinghouse WGen11500TFc Tri-fuel 11500 10500 9500 120/240 V

What is a dual fuel generator and what changes by fuel

The main change is rated output. The iGen2550DFc peaks at 2550 watts on gasoline. On propane, its peak is 2300 watts. Its running output drops in the same way.

The Champion 201278 behaves differently. It lists 4500 starting watts on both fuels. Its running watts still fall from 3500 to 3150 on propane. So check both running and starting figures for each fuel.

Runtime depends on the fuel and the load. Use the maker's runtime figure for each fuel. Do not convert one fuel's runtime into another's.

Dual fuel generator vs tri-fuel and inverter features

Tri-fuel models add natural gas as a third option. The Champion 201176 and Westinghouse WGen11500TFc both list it. On each, natural gas has the lowest rating of the three fuels. A natural gas connection also needs its own fuel pressure and flow check, done by licensed trades.

Inverter is a separate feature. An inverter generator still has an alternator. It adds power electronics to shape the output. A unit can be dual fuel and inverter, as the 201278 is.

Voltage is another separate check. Some listed models offer 120 V only. Others offer 120/240 V. A basic adapter cannot add a voltage the source does not make.

Sources, method and limits

Every figure comes from a manufacturer page. No averages or estimates were added. Each number applies only to its named model.

This guide does not test fit with any appliance or home system. Wattage alone is not a fit result. Voltage, receptacle, run time and installation must also match. Placement follows CPSC guidance.

FAQs

What does dual fuel mean on a generator?

It means the generator is built to run on two fuels. On the models listed here, the two fuels are gasoline and propane. The way you change fuels varies by model. Follow the exact manual for your unit.

Check the rated output for each fuel, too.

Does a dual fuel generator make the same power on each fuel?

Not on the models listed here. The iGen2550DFc runs at 1900 watts on gasoline and 1700 on propane. The Champion 201278 drops from 3500 to 3150 running watts. Its starting rating stays at 4500 watts.

Other models may differ, so read their specifications.

Is tri-fuel the same as dual fuel?

No. A tri-fuel model adds natural gas as a third option. The Champion 201176 runs at 5875 watts on natural gas. The WGen11500TFc runs at 9500 watts on it.

A natural gas hookup needs its own pressure and flow checks by licensed trades.

Where should a dual fuel generator run?

CPSC says to run portable engine generators outdoors only. Keep them at least 20 feet from the home, with the exhaust pointed away. Never run one indoors or in a garage, even with the doors open. The fuel you choose does not change this rule.

Primary documents

What Is a Dual Fuel Generator Verdict

What is dual fuel generator? A dual fuel generator gives you a choice of two fuels. That flexibility is useful if one fuel is hard to get where you live. Output on the second fuel may be lower, as on these models.

If propane is your main fuel, compare the propane generator for home options. Keep the selected fuel's output beside your load plan.