If your home is not on a natural gas line, you already know the fuel question matters. Gasoline is easy to find but goes stale. Propane stores for years but takes up space and has its own quirks. A dual-fuel generator runs on either, which means you are not betting your whole outage plan on one fuel supply.
This guide explains how dual-fuel generators work, what you give up when running on propane, how to estimate propane needs, and which models make sense for rural homes. Specs below come from manufacturer and retailer listings, so confirm current numbers on the product page before you buy.
Why Dual-Fuel Makes Sense Without Natural Gas
- Two fuel sources. If gas stations lose power or run out of fuel during a regional outage, a stored propane tank keeps you running. If propane is hard to refill, you can switch to gasoline.
- Propane stores well. Unlike gasoline, propane does not degrade in the tank, so it avoids the stale-fuel and carburetor-gumming problems that cause many no-starts.
- Cleaner burning. Propane tends to leave fewer deposits in the engine.
- Flexibility. You can fill up with whatever is available, and you can stagger your supplies.
A related category, tri-fuel generators, adds natural gas as a third option. If you do not have a natural gas hookup, you do not need one, and a dual-fuel unit is the better value.
What You Give Up on Propane
Dual-fuel generators produce less power on propane than on gasoline. Based on manufacturer and retailer specs, the drop typically runs roughly 5 to 12 percent depending on the model. A few examples:
| Model | Gasoline (Running) | Propane (Running) |
|---|---|---|
| DuroMax XP13000EH | 10,500 W | 9,975 W |
| Westinghouse WGen9500DF | 9,500 W | 8,500 W |
| Champion 100165 | 7,500 W | 6,750 W |
| Westinghouse WGen5300DFcv | 5,300 W | 4,800 W |
The practical takeaway: if you plan to rely on propane, size your generator using the propane rating, not the gasoline number on the box.
How Much Propane Will You Actually Need?
This is where many first-time owners get surprised. A large generator uses propane quickly, and a standard 20-pound grill cylinder holds only about 4.7 gallons of propane. At half load, a big dual-fuel unit can burn through that in a few hours.
- DuroMax lists roughly 6 hours at 50% load and about 13 hours at 25% load on propane, and suggests a 40-pound tank.
- Reviewers report runtimes in the same ballpark when using a 20-pound cylinder on a large generator, which means one cylinder is not a multi-day supply.
- Smaller dual-fuel units sip less fuel, so a 20-pound cylinder lasts noticeably longer on a 3,500 to 5,000 watt model.
For an extended outage, plan for multiple cylinders, a larger tank (such as a 100-pound cylinder or a bulk tank, if you have one), or a gasoline backup. Also remember that propane flow can be affected by very cold weather, because propane vaporizes poorly at low temperatures. Larger tanks and sheltered (but safely ventilated, outdoor) placement help.
How to Size a Dual-Fuel Generator for Your Home
Add up what you need to run, using running watts plus the largest startup surge, as covered in our guides to rural home wattage and well pump generator sizing. As a rough guide:
| What You Want to Run | Typical Generator Class |
|---|---|
| Fridge, lights, router, a few small items | 3,500 – 4,500 W |
| Add a sump pump, furnace blower, or small well pump | 5,500 – 7,500 W |
| Add a larger well pump plus more circuits | 8,500 – 10,000+ W |
| Add central air conditioning or electric water heating | 10,000+ W |
Features Worth Paying For
- Electric start. Especially valuable on large engines. See our guide to electric-start generators.
- Carbon monoxide sensor. Some models include a CO sensor that shuts the generator down if dangerous levels build up. This is a meaningful safety feature.
- Transfer-switch-ready outlet. A 30-amp or 50-amp 120/240V outlet lets you connect through a transfer switch.
- Low-oil shutoff. Protects the engine.
- Fuel gauge and runtime. Helps you plan refueling.
- Wheel kit. Generators in this class are heavy, so wheels matter.
- Warranty and parts support. Compare terms before buying.
Best Dual-Fuel Generators for Homes Without Natural Gas
Best value starter: WEN DF475T
The WEN DF475T offers 4,750 peak and 3,800 running watts on gasoline, with electric start, a wheel kit, and both 120V and 240V outlets, at a price that sits far below larger dual-fuel units. It handles the essentials, such as a refrigerator, lights, a router, and a few small appliances, and some households add a sump pump or window air conditioner. Whole-home backup is out of reach at this size, so treat it as an essentials generator. #CommissionsEarned
Best mid-size all-rounder: Westinghouse WGen5300DFcv
The Westinghouse WGen5300DFcv produces 5,300 running and 6,500 peak watts on gasoline (4,800 and 5,800 on propane), which is enough for a refrigerator, freezer, lights, a furnace blower, and a sump pump together in many homes. It is a good fit for households that want more headroom than a 4,000-watt unit without moving up to the biggest models. #CommissionsEarned
Best step-up for larger loads: Champion 100165
The Champion 100165 delivers 7,500 running and 9,375 starting watts on gasoline (6,750 and 8,400 on propane), which gives room for a well pump plus the household basics. Champion’s service network and widely available parts are an advantage for rural owners. #CommissionsEarned
Best for home backup with remote start: Westinghouse WGen9500DF
The Westinghouse WGen9500DF is rated at 12,500 peak and 9,500 running watts on gasoline and 11,200 peak and 8,500 running on propane, with a 6.6-gallon tank and remote electric start. Reviewers cite roughly 11 to 12 hours at half load on gasoline. It is transfer-switch ready and strong enough for a refrigerator, well pump, furnace blower, and several circuits at once. A variant with a built-in CO sensor, the WGen9500DFc, exists, so choose that version if the safety feature matters to you. #CommissionsEarned
Best for whole-home loads: DuroMax XP13000EH
The DuroMax XP13000EH is rated at 13,000 starting and 10,500 running watts on gasoline and about 12,350 and 9,975 on propane, with a 500cc engine, an 8.3-gallon tank, and push-button electric start. It is the pick for homes that need to run larger loads, such as central air, a bigger well pump, and the household basics together. It is a big, heavy machine and a thirsty one, so plan your fuel and moving logistics. #CommissionsEarned
Quick Comparison Table
| Model | Gas Peak / Running | Propane Running | Best For |
|---|---|---|---|
| WEN DF475T | 4,750 / 3,800 W | Lower (see spec sheet) | Value, essentials only |
| Westinghouse WGen5300DFcv | 6,500 / 5,300 W | 4,800 W | Mid-size home, good balance |
| Champion 100165 | 9,375 / 7,500 W | 6,750 W | Larger loads, service network |
| Westinghouse WGen9500DF | 12,500 / 9,500 W | 8,500 W | Home backup, remote start, CO-sensor variant |
| DuroMax XP13000EH | 13,000 / 10,500 W | 9,975 W | Whole-home loads, maximum power |
#CommissionsEarned
Specs are from manufacturer and retailer listings and can change by model year or variant. Verify on the listing before you buy.
Accessories That Complete the Setup
To connect a generator to your home safely, a manual transfer switch is the standard choice. The Reliance Controls Pro/Tran 2 306CRK is a six-circuit, 30-amp, 125/250V switch rated for up to 7,500 watts, which includes a power inlet box and a cord, and it lets you choose which circuits (such as a well pump or refrigerator) run from the generator. It fits 30-amp L14-30 generator outlets, and installation should be done by a licensed electrician. #CommissionsEarned
For connecting a generator that has a 30-amp L14-30 outlet, the PlugSaf 25-foot 30-amp L14-30 generator cord is a heavy-duty, twist-lock 10-gauge cord that keeps the generator a safe distance from the house. Larger generators often use a 50-amp outlet, so confirm your outlet type first. #CommissionsEarned
Every generator setup should include a Kidde battery-operated carbon monoxide alarm inside the home near sleeping areas, as an extra layer of protection beyond any CO sensor on the generator. #CommissionsEarned
If you use gasoline as one of your fuels, STA-BIL fuel stabilizer helps keep stored gasoline usable, which is easy to overlook in a dual-fuel setup where gasoline may sit while you run propane. #CommissionsEarned
Safety Basics for Dual-Fuel Generators
- Run it outdoors only, well away from the house, with exhaust directed away from windows, doors, and vents. A common guideline is at least 20 feet.
- Never run it in a garage or enclosed space, even with the door open.
- Store propane cylinders upright and outdoors, in a ventilated area, away from ignition sources.
- Check propane connections for leaks by brushing soapy water on the fittings. Bubbles indicate a leak.
- Use a transfer switch or interlock kit installed by a licensed electrician. Never backfeed through a wall outlet.
- Let the generator cool before refueling, and never refuel a running or hot engine.
Common Mistakes to Avoid
Sizing for the gasoline rating. If you will run on propane, use the lower propane number.
Buying one 20-pound cylinder and calling it done. Large generators use propane fast. Plan for several cylinders or a larger tank.
Ignoring the CO sensor. Some variants include it. It is a worthwhile safety upgrade.
Forgetting about weight. Large dual-fuel generators are heavy. Plan how you will move and position them.
Skipping the transfer switch. Extension cords through windows are not a safe way to power a home.
FAQ
What is a dual-fuel generator?
A generator that can run on gasoline or propane, usually with a simple switch or selector to change fuels.
Do I need a dual-fuel generator if I have no natural gas?
No, but it adds flexibility. Gasoline is easy to find, and propane stores for years, so having both is a strong outage strategy.
Is propane or gasoline better for generators?
Propane stores better and burns cleaner, but produces somewhat less power and needs a large tank for long runs. Gasoline provides more power but degrades in storage.
How long will a 20-pound propane tank run a generator?
It depends on the generator and load. A large generator at half load may use a 20-pound cylinder in a few hours, while a smaller unit can run considerably longer.
Can I switch fuels while the generator is running?
Procedures vary by model. Follow your owner’s manual for fuel switching.
Can a dual-fuel generator run a well pump?
Many mid- to large-size dual-fuel units can, if the generator’s 240V output and surge rating match the pump’s requirements. See our well pump sizing guide.
This article is general information, not electrical advice. Have a licensed electrician install any generator connection or transfer switch.
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