7 Best Dual-Fuel Generators for Survival & Home Backup
The best dual fuel generators for emergency backup give you something especially valuable during a power outage: options. Instead of depending on a single fuel source, you can run on gasoline or propane depending on what you have available, how much power you need, and how long the outage lasts.
This post contains affiliate links. I may earn a small commission at no extra cost to you. Learn more.
For home backup and emergency preparedness, that flexibility can make a major difference. A properly sized generator can keep refrigerators and freezers cold, charge phones and power stations, run lights and communications equipment, and support other essential loads when utility power is unavailable.
Dual-fuel generators are particularly useful for longer outages because gasoline and propane have different strengths. Gasoline is widely available and may provide higher output on some generators, while propane is easier to store for extended periods and avoids many of the storage problems associated with gasoline.
If you’re still deciding between generator types, see our Best Survival Generators guide for a broader comparison of backup-power options.
Cold-weather outages require additional planning beyond simply owning a generator. Our Winter Blackout Survival Guide covers heating, food, power, and other priorities when an outage lasts for days.
What This Guide Covers
We’ll compare seven dual-fuel generators for different backup-power needs, from smaller essential-load systems to larger home and property setups. We’ll look at output, fuel options, portability, noise considerations, and the types of loads each generator is best suited to handle.
The goal isn’t simply to buy the generator with the largest wattage number. It’s to choose a model that matches your actual emergency loads, fuel plan, and expected outage conditions.
This guide is also part of our Grid-Down Survival Power plan, where we cover generators, batteries, solar charging, load management, and other strategies for keeping essential equipment operating during extended outages.
Why Dual-Fuel Generators Make Sense for Emergency Backup
The biggest advantage of a dual-fuel generator is redundancy. Instead of depending entirely on gasoline or propane, you have two fuel options available when utility power is down.
That flexibility becomes more valuable as an outage gets longer. Fuel availability can change quickly during severe weather and widespread emergencies, and the fuel that’s easiest to obtain today may not be the one that’s available several days later.
Two Fuel Options
Most dual-fuel generators can operate on either gasoline or propane. That allows you to choose a fuel based on availability, storage, generator output, and the length of the outage.
Gasoline is widely available and many generators produce their highest rated output when running on it. Propane is generally easier to store for long periods because it does not degrade the way gasoline does.
Better Long-Term Fuel Storage
Gasoline requires more active storage management. Over time it can degrade and create fuel-system problems, so stored gasoline needs to be handled and rotated appropriately.
Propane stored in a sound, properly maintained cylinder does not degrade like gasoline. That makes it useful as part of a long-term emergency fuel plan, although cylinders, valves, regulators, and hoses still need to be stored and maintained correctly.
Understand the Output Difference
Don’t assume a dual-fuel generator produces the same wattage on both fuels. Many models have separate gasoline and propane starting and running watt ratings.
That difference matters when you’re powering equipment with high startup demand, such as refrigerators, freezers, well pumps, sump pumps, furnace blowers, and some power tools.
Always size your emergency loads using the generator’s rating for the fuel you actually expect to use.
Runtime Depends on More Than Fuel Type
Generator runtime varies with electrical load, engine size, generator design, fuel-tank capacity, propane-cylinder size, weather conditions, and other factors.
Instead of relying on a generic hours-per-tank estimate, compare the manufacturer’s runtime information and then test your generator under a realistic emergency load.
Build a Two-Fuel Plan
A practical dual-fuel strategy doesn’t require choosing gasoline or propane permanently. You can keep propane available for long-term storage while maintaining a manageable supply of gasoline for situations where you need it.
Know the output and approximate runtime your generator delivers on each fuel before an outage. That makes it much easier to decide when to switch fuels and how long your stored supply may last.
Dual-Fuel Generator vs. Solar and Battery Backup
Generators and battery-based backup systems solve different problems. A generator can continue producing electricity as long as you have fuel, while batteries provide quiet power without running an engine. Solar panels can recharge compatible battery systems when sufficient sunlight is available.
For longer outages, combining these technologies can be more efficient than relying on any one of them alone. A battery system can handle smaller loads quietly while the generator is shut down, and the generator can be used for larger loads or battery charging when needed.
If you’re comparing the different approaches, see our Best Survival Generators guide for a broader look at emergency-power options.
A dual-fuel generator isn’t automatically the best solution for every household, but having two fuel options can provide valuable flexibility when you’re planning for outages that may last longer than a few hours.
1. WEN DF360iX 3600W Dual-Fuel Inverter Generator — Best Compact & Quiet Pick
The WEN DF360iX is a compact dual-fuel inverter generator designed for essential backup power, camping, RV use, and situations where portability and quieter operation matter more than whole-home output.
It runs on either gasoline or propane, giving you another fuel option during an extended outage. Its inverter design also makes it a good fit for electronics and other sensitive equipment when used within the generator’s rated capacity.
Key Specifications
Price and availability can change. Check Amazon’s current listing before purchasing.
Why It Stands Out
The DF360iX fills an important role in an emergency-power plan: it’s large enough to handle a carefully managed group of essential loads without forcing you into a heavy, high-output home-backup generator.
Because it’s an inverter generator, it’s particularly useful when your outage plan includes electronics such as routers, chargers, laptops, communications equipment, and other compatible devices.
WEN also includes its CO Watchdog system, which can automatically shut the generator down when dangerous carbon-monoxide conditions are detected around the unit. That safety feature does not change the requirement to operate the generator outdoors and away from doors, windows, vents, and occupied areas.
Best For
- Refrigerator or freezer backup
- Lights and fans
- Internet and communications equipment
- Device charging and electronics
- RV and camping use
- Smaller emergency-power setups
- Households prioritizing portability and lower noise
Limitations
This is still an essentials-class generator. It isn’t designed to power an entire house or multiple large electrical loads simultaneously.
It’s also a 120V generator. If your emergency plan includes 240V equipment such as certain well pumps, large HVAC equipment, or other 240V circuits, choose one of the larger 120/240V generators later in this guide.
Best Use Case
The WEN DF360iX makes the most sense for someone who wants dependable emergency power without buying more generator than they need.
Use it for a carefully selected group of essential loads, and calculate your actual running and startup wattage before adding additional appliances.
2. Champion 4250W Dual-Fuel Open-Frame Inverter Generator — Best All-Around Pick
The Champion 4250W Dual-Fuel Open-Frame Inverter Generator is a strong middle-ground option for emergency backup power. It provides more capacity than the smaller WEN DF360iX while retaining inverter technology for cleaner power and improved fuel efficiency.
It can operate on either gasoline or propane, making it useful for households that want fuel flexibility without moving all the way up to a large conventional home-backup generator.
Key Specifications
Price and availability can change. Check Amazon’s current listing before purchasing.
Why It Stands Out
The Champion 4250W gives you more usable output than a small portable inverter while avoiding the size and fuel demands of the much larger home-backup generators later in this guide.
Its inverter design is another advantage. Champion specifies clean power with less than 3% total harmonic distortion, making it suitable for compatible electronics such as routers, computers, chargers, televisions, and communications equipment.
The open-frame design also helps keep the generator relatively practical for emergency use while providing enough output to handle several carefully managed household essentials.
Best For
- Refrigerator and freezer backup
- Lights, fans, and communications equipment
- Electronics and device charging
- RV use
- Emergency power for several essential loads
- Households wanting more capacity than a compact inverter
Limitations
This is still a 120V generator, so it isn’t the right choice if your backup plan requires 240V power for equipment such as certain well pumps, HVAC systems, or other large household circuits.
It’s also an open-frame inverter design rather than a fully enclosed inverter generator. Buyers prioritizing the smallest possible package or the quietest operation may prefer a smaller enclosed model.
Best Use Case
The Champion 4250W is best for a household that wants to run several essential loads while retaining the cleaner output and efficiency advantages of inverter technology.
It’s a particularly useful middle ground between a small essentials-only generator and the larger 120/240V home-backup generators farther down this list.
3. WEN DF480iX 4800W Dual-Fuel Inverter Generator — Best Mid-Size Inverter
The WEN DF480iX steps up from smaller inverter generators by providing more emergency-power capacity while retaining the quieter operation and cleaner power associated with an enclosed inverter design.
It can run on either gasoline or propane and includes electric start, making it a strong choice for households that want a portable generator capable of handling several essential loads without moving into a large conventional home-backup unit.
Key Specifications
Price and availability can change. Check Amazon’s current listing before purchasing.
Why It Stands Out
The DF480iX gives you a useful increase in output over smaller inverter generators without jumping all the way to a heavy 6,500- to 12,500-watt home-backup generator.
That extra capacity can make a meaningful difference during an outage when you’re trying to operate a refrigerator or freezer along with lights, fans, communications equipment, chargers, and other essential 120V loads.
Electric start is another practical advantage, particularly during an extended outage when you may be starting and stopping the generator regularly to conserve fuel. WEN also includes its CO Watchdog system, which can automatically shut the generator down when dangerous carbon-monoxide conditions are detected around the unit.
As with every portable fuel-burning generator, the CO shutdown system is an additional safety feature—not a substitute for proper placement. The generator must still be operated outdoors and away from doors, windows, vents, and occupied spaces.
Best For
- Refrigerator and freezer backup
- Several essential household loads
- Lights, fans, and communications equipment
- Electronics and device charging
- RV and camping use
- Households wanting electric start
- Buyers wanting more capacity without a large conventional generator
Limitations
The DF480iX is still a 120V generator. It is not the right choice if your emergency-power plan requires 240V output for equipment such as certain well pumps, central HVAC equipment, or other 240V household circuits.
It’s also larger than the compact DF360iX in the first position, so buyers who only need basic refrigerator, lighting, and electronics backup may not need the additional capacity.
Best Use Case
The WEN DF480iX is a strong fit for someone who wants a substantial 120V emergency-power system while still prioritizing inverter technology, portability, and electric-start convenience.
For a household that doesn’t need 240V power but finds a 2,500- to 3,600-watt generator too restrictive, this is one of the most useful size classes in the guide.
4. WEN DF475T 4750W Dual-Fuel Portable Generator — Best Budget Home Backup
The WEN DF475T is a more traditional dual-fuel portable generator aimed at buyers who care more about affordable backup power and 120/240V capability than inverter technology or ultra-quiet operation.
It runs on either gasoline or propane and includes electric start. Most importantly for home-backup planning, it can provide both 120V and 240V power, giving it capabilities that the smaller 120V inverter generators earlier in this guide don’t have.
Key Specifications
Price and availability can change. Check Amazon’s current listing before purchasing.
Why It Stands Out
The biggest advantage of the DF475T is the combination of dual-fuel operation, 120/240V output, electric start, and a relatively modest generator size.
That makes it more versatile for home-backup applications than the 120V inverter generators earlier in this guide. Depending on the equipment you’re trying to power, 240V capability can be important for certain well pumps and other household loads.
The ability to switch between gasoline and propane is also valuable during a longer outage. Propane stores differently than gasoline and gives you another fuel option when gasoline is difficult to obtain.
For connection to household circuits, use properly installed transfer equipment or another code-compliant connection method appropriate for your electrical system. Never backfeed a house through a receptacle.
Best For
- Budget-conscious home backup
- Refrigerators and freezers
- Lights and other essential household loads
- Some compatible 240V equipment
- Well-pump backup when the pump’s actual electrical requirements fall within the generator’s capacity
- Households wanting gasoline and propane flexibility
- Buyers who don’t need an inverter generator
Limitations
The DF475T is a conventional generator rather than an inverter generator, so buyers prioritizing lower noise, maximum fuel efficiency at light loads, or inverter-style power may prefer one of the earlier models.
Its 240V capability also doesn’t mean it can automatically run every 240V appliance. Large well pumps, electric water heaters, central air conditioners, and other high-demand equipment can exceed the generator’s available output, particularly during startup.
Best Use Case
The WEN DF475T makes the most sense for someone who wants affordable dual-fuel emergency power and needs 120/240V capability without buying a much larger generator.
It’s particularly attractive as an entry-level home-backup generator when your essential-load calculation fits within its output and you have the proper electrical connection equipment installed.
5. Westinghouse 6500W Dual-Fuel Portable Generator — Best Mid-Size Home Backup
The Westinghouse 6500W Dual-Fuel Portable Generator moves farther into serious home-backup territory. It’s a good fit for households that need more capacity than the smaller generators above but don’t necessarily need one of the massive 10,000-watt-plus models.
With gasoline and propane capability, 120/240V output, and connections intended for home-backup and RV applications, this size class can handle a broader collection of essential loads during an extended outage.
Key Specifications
Price and availability can change. Check Amazon’s current listing before purchasing.
Why It Stands Out
The biggest reason to move into this generator class is capacity. Rather than planning around only a refrigerator, freezer, lights, and electronics, you have more room to build a larger emergency-power plan around several essential household loads.
The 120/240V capability also makes this a more appropriate candidate for a properly configured home-backup system than the smaller 120V-only inverter generators earlier in the guide.
Its transfer-switch-ready connection is especially useful if your goal is to power selected household circuits instead of running extension cords to individual appliances. Any connection to a home’s electrical system should use properly installed transfer equipment or another code-compliant method appropriate for the electrical system.
Best For
- Extended home power outages
- Refrigerator and freezer backup
- Multiple essential household circuits
- Lights, fans, communications equipment, and electronics
- Compatible 120V and 240V loads
- RV backup power
- Households wanting more capacity without moving to an extra-large generator
Limitations
A generator in this class is heavier, louder, and generally more fuel-hungry than the smaller inverter generators earlier in the guide. If your outage plan only requires a refrigerator, a few lights, and electronics, this may be more generator than you need.
Its larger output also doesn’t guarantee that it can start every major household appliance. Well pumps, air conditioners, electric water heaters, and other high-demand equipment should be sized individually using their actual running and startup requirements.
Best Use Case
This Westinghouse is best suited to someone building a more substantial home-backup system and wanting enough capacity to operate multiple essential loads rather than powering one or two appliances at a time.
It represents a useful middle ground between portable inverter generators and the much larger home-backup generators coming next in the guide.
6. WEN DF8000X 8000W Dual-Fuel Portable Generator — Best 120/240V Home Backup
The WEN DF8000X is designed for households that need substantially more backup capacity than a compact inverter generator can provide. With dual-fuel operation and 120/240V output, it’s better suited to a larger emergency-power plan involving multiple household circuits and higher-demand equipment.
This is the type of generator to consider when your outage plan extends beyond keeping a refrigerator, freezer, lights, and electronics running. Its larger output gives you more flexibility, provided you still calculate the running and startup requirements of the equipment you intend to power.
Key Specifications
Price and availability can change. Check Amazon’s current listing before purchasing.
Why It Stands Out
The DF8000X provides a significant jump in usable backup capacity compared with the smaller generators earlier in this guide. That makes it much better suited to a household that wants to power several circuits through properly installed transfer equipment rather than relying primarily on extension cords.
Its 120/240V capability is especially important for homes with essential 240V equipment. Depending on actual starting and running requirements, that could include certain well pumps and other compatible household loads.
Dual-fuel operation also gives you flexibility during a prolonged outage. You can use gasoline when it’s readily available while maintaining propane as another stored-fuel option.
The DF8000X also includes WEN’s CO Watchdog system. As with every carbon-monoxide shutdown system, it should be treated as an additional layer of protection rather than permission to operate the generator in an unsafe location. Portable generators must remain outdoors and properly separated from doors, windows, vents, and occupied spaces.
Best For
- Larger home-backup systems
- Multiple essential household circuits
- Refrigerators and freezers
- Compatible well pumps and other 240V loads
- Lights, fans, communications equipment, and electronics
- Longer power outages
- Households wanting gasoline and propane flexibility
Limitations
The additional output comes with the usual tradeoffs of a larger conventional generator: more weight, more noise, and greater fuel consumption than a small inverter generator.
Even at this output level, you shouldn’t assume the generator can run every major appliance in the house simultaneously. Central air conditioning, electric water heating, electric ranges, large well pumps, and similar loads can consume substantial power or have high startup requirements.
Best Use Case
The WEN DF8000X is best for a household that wants a serious 120/240V emergency-power setup but doesn’t necessarily need to jump into the largest generator class.
Paired with properly installed transfer equipment and a carefully planned load schedule, it can provide a practical balance between substantial home-backup capability and the fuel demands of an extra-large generator.
7. Westinghouse 12,500W Dual-Fuel Portable Generator — Best High-Capacity Home Backup
The Westinghouse 12,500W Dual-Fuel Portable Generator is the high-capacity choice in this guide. It’s designed for households that need considerably more emergency power than the smaller portable generators above can provide.
With gasoline and propane capability, 120/240V output, electric start, and home-backup connections, this generator is better suited to demanding outage plans involving multiple household circuits and larger electrical loads.
Key Specifications
Price and availability can change. Check Amazon’s current listing before purchasing.
Why It Stands Out
The biggest advantage of this Westinghouse is straightforward: substantially more available power. Its higher output gives you more flexibility when building a home-backup plan around refrigerators, freezers, lighting, communications equipment, pumps, and other essential loads.
The 120/240V output also makes it appropriate for more demanding home-backup configurations. When paired with properly installed transfer equipment, it can supply selected household circuits rather than requiring extension cords to individual appliances.
Remote electric start is another practical feature on a generator this size, particularly during a prolonged outage when the generator may be started and stopped according to a load and fuel-conservation schedule.
Despite the additional capacity, this should not be treated as unlimited power. Large central air conditioners, electric water heaters, electric ranges, well pumps, and other high-demand equipment can consume a substantial portion of the generator’s available output.
Best For
- High-capacity home backup
- Multiple essential household circuits
- Refrigerators and freezers
- Compatible well pumps and other 240V equipment
- Homes with larger emergency-power requirements
- Extended outages
- Households wanting gasoline and propane fuel options
Limitations
More generator isn’t automatically better. A unit in this class is considerably heavier and can consume substantially more fuel than a smaller generator, especially as electrical load increases.
If your emergency plan consists primarily of keeping a refrigerator, freezer, lights, internet equipment, and a few small devices running, one of the smaller generators in this guide may be more practical and economical.
You should also calculate the actual running and startup requirements of large loads rather than assuming the generator can operate an entire house simultaneously.
Best Use Case
This Westinghouse is best for a household with genuinely high emergency-power requirements, particularly when several essential circuits or compatible 240V loads need to remain available during an outage.
For the right home, it provides significantly more flexibility than a small portable generator. For a household with modest emergency-power needs, however, the additional size, fuel consumption, and capacity may be unnecessary.
Dual-Fuel Generator Comparison
The best generator isn’t necessarily the one with the highest wattage. Compare running output, voltage, generator type, and intended use before deciding which model fits your backup-power plan.
How to Read the Wattage Ratings
Running watts are the amount of power a generator can continuously supply. Starting, surge, or peak watts are the additional power available for a short period when equipment with a motor or compressor starts.
Pay close attention to the propane rating if propane will be your primary emergency fuel. Many dual-fuel generators produce less running and starting power on propane than they do on gasoline, so your generator should be sized using the output available from the fuel you actually expect to use.
Voltage is just as important as wattage. The WEN DF360iX, Champion 4250W, and WEN DF480iX are 120V options suited primarily to essential 120V loads. The WEN DF475T, Westinghouse 6500W, WEN DF8000X, and Westinghouse 12,500W provide 120/240V capability, making them better candidates when your backup plan includes compatible 240V equipment or a properly configured 120/240V home-backup system.
Don’t choose a generator based on peak wattage alone. Compare its continuous running output, fuel-specific ratings, voltage, and connection options against the equipment you actually need during an outage.
Don’t Size a Generator From Generic Appliance Wattages
Appliance power consumption varies by model. Instead of assuming every refrigerator, freezer, pump, furnace blower, CPAP machine, or other device uses the same amount of electricity, check the equipment label or manufacturer specifications whenever possible.
Add the running loads you expect to operate at the same time, then account for the starting demand of motors and compressors. Leave some operating headroom rather than planning to run the generator continuously at its maximum rating.
For most households, the goal isn’t to buy the largest generator available. It’s to choose enough capacity for your actual essential loads while considering fuel consumption, noise, portability, voltage requirements, and how the generator will connect to those loads.
Hybrid Backup Power: Generator + Battery + Solar
A dual-fuel generator doesn’t have to supply every load for the entire outage. During a longer blackout, combining a generator with battery storage and solar charging can reduce generator runtime, conserve fuel, and provide quiet power when running an engine isn’t necessary.
The basic strategy is simple: use the generator when you need substantial power or fast battery charging, use batteries for smaller loads between generator runs, and use available solar energy to supplement battery charging.
Use the Generator for Larger Loads and Battery Charging
Run the generator outdoors when you need to operate higher-demand equipment or recharge a compatible battery system. Depending on your generator and household loads, this may include refrigeration, pumps, tools, heating-system components, or other equipment within the generator’s available capacity.
You can also use the generator’s AC output to recharge a compatible portable power station or properly configured battery system. Always stay within the generator’s output rating and the battery system’s allowable AC charging input.
Use Battery Power Between Generator Runs
Once the battery system is charged, shut the generator down when engine power is no longer needed. Battery storage can then handle appropriate loads such as lights, communications equipment, routers, fans, chargers, and other lower-demand devices without fuel consumption or generator noise.
This approach can be especially useful overnight because the fuel-burning generator remains shut down while compatible indoor loads operate from battery power.
Add Solar Charging When It Makes Sense
Solar panels can provide another charging source for a compatible battery or power station. Actual solar production depends on panel wattage, available sunlight, season, weather, panel orientation, charging limits, and system losses.
Solar doesn’t guarantee that you’ll eliminate generator use, but every useful amount of energy recovered from sunlight can reduce the energy that must come from stored fuel.
A Simple Hybrid Power Strategy
- Use the generator outdoors for larger loads and faster charging
- Recharge your battery system while generator capacity is available
- Shut the generator down when it isn’t needed
- Use battery power for appropriate lower-demand and overnight loads
- Use solar charging when conditions allow
- Track battery state of charge and remaining fuel
- Adjust generator runtime based on actual energy consumption
Size the System From Your Actual Energy Use
There isn’t one generator-runtime schedule or solar-panel size that works for every household. A refrigerator, freezer, well pump, communications equipment, fans, and other loads can consume very different amounts of energy depending on the specific equipment and how often it operates.
Before building a hybrid system, determine how much energy your essential loads use each day. Then size the battery capacity, generator charging plan, solar input, and stored fuel around that requirement.
If you’re comparing generator and battery-based backup options, see our Best Survival Generators guide.
Generator Placement Still Matters
A hybrid system may reduce generator runtime, but it doesn’t change generator safety requirements. Operate portable fuel-burning generators outdoors and follow the manufacturer’s required clearance and placement instructions. Keep exhaust directed away from doors, windows, vents, and occupied areas.
Don’t place a running generator inside a garage, shed, homemade sound enclosure, or other enclosed or partially enclosed space in an attempt to reduce noise. Never modify airflow or exhaust arrangements in a way that conflicts with the generator manufacturer’s instructions.
For a more detailed explanation of combining these technologies, see our Solar Generator Hybrid Backup guide.
A well-designed hybrid system isn’t about eliminating fuel use entirely. It’s about using each energy source where it works best so you can reduce unnecessary generator runtime and make your available fuel and stored energy last longer.
Fuel Storage, Safety & Maintenance
A dual-fuel generator is only useful if you have fuel available and the machine is ready to run. Build your fuel and maintenance plan before an outage rather than figuring it out after the grid goes down.
Propane Storage
Propane is particularly useful for emergency preparedness because the fuel doesn’t degrade the way gasoline does. Store cylinders upright outdoors in an appropriate location and inspect the tank, valve, regulator, and hose before use.
Cold weather can reduce a propane tank’s ability to vaporize fuel fast enough to supply a heavily loaded generator. Larger tanks generally provide greater vaporization capacity than small cylinders, which can matter during extended winter outages.
Gasoline Storage
Store gasoline only in approved fuel containers and follow local fire and storage requirements. Date your stored fuel, rotate it regularly, and use fuel stabilizer according to the product and generator manufacturer’s instructions when appropriate.
Don’t assume stored gasoline will be ready indefinitely. Fuel age, ethanol content, storage temperature, container quality, and generator design can all affect reliability.
Carbon Monoxide and Generator Placement
Never operate a portable fuel-burning generator inside a house, garage, basement, shed, or other enclosed or partially enclosed space. Operate it outdoors and follow the generator manufacturer’s placement and clearance requirements. Keep exhaust directed away from doors, windows, vents, and occupied areas.
Install and maintain carbon-monoxide alarms inside your home according to the alarm manufacturer’s instructions.
Maintenance
Follow the maintenance schedule in your generator’s owner’s manual. Keep the correct engine oil and commonly needed maintenance items available before an emergency. Periodically inspect cords, plugs, fuel hoses, connections, and the generator itself for damage.
Test the generator periodically so a mechanical, fuel, or starting problem doesn’t first reveal itself during an actual blackout.
Grounding and neutral-bonding requirements depend on the generator and how it is being used. Our Generator Grounding and Bonding Guide explains what to check before connecting your system.
Generator Readiness Checklist
- Store gasoline and propane safely
- Rotate stored gasoline as needed
- Keep the correct engine oil available
- Inspect propane hoses and regulators
- Check cords and plugs for damage
- Test the generator periodically
- Maintain working carbon-monoxide alarms
- Know your generator’s grounding and bonding configuration
- Keep the owner’s manual accessible
How to Size a Generator for an Outage
Don’t choose a generator based only on the largest wattage number printed on the box. Size it around the equipment you actually need to operate.
- List your essential loads. Include refrigeration, lighting, communications, heating equipment, pumps, medical equipment, or anything else you need during an outage.
- Find the actual wattage requirements. Check equipment labels or manufacturer specifications for running watts and, where applicable, starting or surge requirements.
- Determine which loads will operate simultaneously. You may not need to run everything at the same time.
- Account for starting loads. Refrigerators, freezers, pumps, compressors, and other motor-driven equipment can require considerably more power during startup than while running.
- Check your intended fuel. If you expect to operate primarily on propane, size the system using the generator’s propane output rather than its higher gasoline rating.
- Leave operating headroom. Don’t design your emergency plan around continuously operating the generator at its absolute maximum output.
Use our Generator Runtime & Fuel Calculator to estimate how long your generator may operate and how much fuel you should plan for during an extended outage.
If you’re combining a generator with stored battery power, use our Battery & Power Station Runtime Calculator to estimate battery runtime and our Solar Panel Charging Calculator to estimate solar recharge time.
If you plan to supply household circuits rather than individual appliances, read our Transfer Switch for Portable Generators Guide before designing the connection.
Common Dual-Fuel Generator Mistakes
A good generator can still become unreliable or dangerous if the rest of the backup-power plan is poorly designed. Common mistakes include:
- Buying a generator without calculating actual loads
- Ignoring the lower output some generators produce on propane
- Storing gasoline too long without an appropriate rotation plan
- Failing to test the generator before an emergency
- Operating a generator too close to a building or opening
- Assuming a CO shutdown sensor makes unsafe placement acceptable
- Connecting a generator to household wiring without proper transfer equipment
- Ignoring starting watts for motors, pumps, and compressors
- Buying a 120V generator when the backup plan requires 240V equipment
- Failing to plan enough fuel for an extended outage
Before You Buy
- Calculate your essential running loads
- Account for startup surge
- Decide whether you need 120V or 120/240V
- Compare gasoline and propane output ratings
- Estimate your fuel requirements
- Decide whether you need inverter-quality power
- Plan safe outdoor generator placement
- Determine how power will reach your appliances or home circuits
Final Thoughts
A dual-fuel generator gives you something especially valuable during a prolonged outage: options. Gasoline can provide maximum output on many models, while propane gives you another stored fuel source that doesn’t degrade like gasoline.
The right generator depends on what you’re actually trying to power. A lightweight inverter may be enough for refrigeration, communications, lights, and other essentials. A household with 240V pumps or substantially larger loads may need a 120/240V generator and properly installed transfer equipment.
Don’t automatically buy the largest generator you can afford. Larger generators generally require more fuel, are harder to move, and may provide capacity you’ll rarely use. Calculate your loads first, then choose the smallest generator that provides adequate output and reasonable headroom for your emergency plan.
For longer outages, combining a generator with battery storage and solar charging can reduce generator runtime and stretch stored fuel considerably further.
Continue Building Your Backup Power Plan
- Grid-Down Survival Power: Off-Grid Energy Playbook
- Best Survival Generators
- Safe Generator Power Connections
- Transfer Switch for Portable Generators
- Generator Grounding and Bonding
- Best Solar Gear for Summer Survival
Survival is for the savvy. Build your backup-power system before the outage so you’re testing a plan when the grid fails — not inventing one.
Affiliate disclosure: We may earn a commission from qualifying purchases at no extra cost to you.
