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Using Fuel Generators for Alternative Power

When the power goes out, a fuel-powered generator can provide on-demand electricity for many of the same appliances you rely on every day. Instead of switching entirely to alternative cooking, lighting, and heating methods, a generator lets you keep key household loads running - from refrigerators and medical equipment to lights, fans, and device chargers. This page focuses on fuel-powered generators as backup solutions - from smaller portable models to larger standby and whole-home systems that support selected household circuits. Because they can support higher-wattage loads, fuel generators are especially helpful during longer outages or severe storms. Having the right generator in place can reduce disruption, protect your food, and help your home feel more “normal” until grid power is restored.

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How Fuel Generators Keep Your Essentials Powered
diagram of a fuel generator showing parts mentioned here diagram of a fuel generator showing parts mentioned here

What is a fuel-powered generator?

A fuel-powered generator is a compact power system that converts the energy in gasoline, propane, diesel, or natural gas into electricity. Most units bring several key components together:

  • Engine: burns fuel to create mechanical energy
  • Alternator: converts that mechanical energy into electrical power
  • Fuel Tank: stores gasoline, propane, diesel, or a natural gas supply
  • Control Panel: with outlets, breakers, and sometimes meters or displays
  • Transfer Switch: connects the generator to selected home circuits - for standby and whole-home models

During an outage, the engine runs, the alternator produces electricity, and that power is delivered either directly to appliances or to your home’s electrical panel, depending on the type of generator and installation.

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Types of Fuel Generators

Fuel generators come in three main categories. Each has different costs, installation needs, and ideal use cases.

Portable | Standby | Whole-Home

Portable Fuel Generators

Portable generators are smaller, movable units that you store until needed, then roll or carry into position outdoors. They’re typically noisier and provide less overall power than permanently installed standby models, but they offer a lot of flexibility and can be used in many different situations.

You can either:

  • connect them to your home’s electrical system through a transfer switch (installed by a licensed electrician)
  • plug appliances directly into the generator using heavy-duty outdoor-rated extension cords that can safely handle the electrical load

Things to consider before you buy

When purchasing a portable fuel generator for emergency preparedness, you'll face a few key choices. The first is fuel type, which determines not only availability during an emergency but also the fuel's storage and long-term usability. The second is generator type - choosing between inverter models or conventional units. Understanding their strengths and limitations will help you determine the right fit for you.

Fuel Types Used

Most portable generators are designed to run primarily on gasoline. Many newer models are dual fuel, allowing you to choose between gasoline and propane; some larger or specialized generators are also available in diesel or natural gas configurations. This flexibility can be valuable if one type of fuel is easier for your household to store. Be sure to check out the difference between storing gasoline and propane.

Portable Inverter Generators

These generators are designed to be:

  • quieter than conventional models
  • more fuel-efficient, especially at partial loads
  • better at producing clean, stable power that is safer for sensitive electronics like laptops, medical devices, and modern appliances

Because of these advantages, they’re popular in neighborhoods, campgrounds, and situations where noise and power quality matter. The tradeoff is price - inverter generators usually cost more than conventional models with similar output.

Portable Conventional Generators

These generators are:

  • generally less expensive up front
  • built with rugged components to handle continuous heavy loads
  • well-suited for extended use during long outages as long as fuel supplies remain available

However, they usually run at higher noise levels and often need more frequent maintenance, such as regular oil changes and spark plug inspections.

Best Uses
  • backup for short to medium outages
  • powering a refrigerator and freezer
  • running lights, fans, and small heaters - within wattage limits
  • powering tools or equipment outside
Portable Brands

Inverter: Briggs & Stratton, Champion, WEN, Honda, Westinghouse, and Predator

Conventional: DuroMax, Champion, and Westinghouse

Cost Range

Portable gasoline and propane generators are available across a wide price range, typically from about $500 to $4,000, depending on wattage, features, and fuel options. Propane-capable models often cost more than gasoline-only units with similar power output because many are designed as dual-fuel appliances.

Capacity Range

About 3,000–5,000 watts

Standby Generator Systems

Standby generator systems are permanently installed backup power solutions that operate automatically. Within seconds of a utility outage, an automatic transfer switch senses the power loss, commands the generator to start, and then transfers selected circuits over to generator power. These systems are tied into your home’s electrical panel and are sized to keep key home circuits running during an outage. This automatic operation means you don’t have to be home to get your backup power running.

Standby systems typically:

  • sit in a fixed location outside your home
  • connect to your home’s main or sub-panel via a transfer switch
  • are fueled by natural gas, propane, or diesel, depending on the model and installation
  • are sized to support specific circuits (or, in some cases, most of the home)

You and your installer choose which circuits to prioritize based on your needs. Common choices include refrigerators and freezers, heating systems, essential lighting, and internet equipment.

Best Uses
  • backup for moderate to long outages without manual setup
  • keeping essential circuits powered
  • protecting against basement flooding by powering sump pumps during storms
  • ideal if you want hands-off reliability for partial-house coverage
Standby Brands

Generac, Briggs & Stratton, and Champion.

Cost Range

The cost of a standby generator varies widely based on size, features, and fuel type. A smaller, lower-capacity unit might run around $2,000 to $5,000 for the generator itself, not including installation. Larger systems with more capacity, more advanced controls, or additional features often cost considerably more, and professional installation adds to the total investment.

Capacity Range

Commonly 7,000–18,000+ watts

Whole-Home Generator Systems

Whole-home generator systems are larger, permanently installed systems designed to power your entire home or nearly all of it during an outage. Like standby generators, they work with an automatic transfer switch but are typically sized and configured to handle higher loads and more circuits at once.

These systems are:

  • permanently installed outdoors in a sound-reducing housing
  • connected to your home’s main service panel
  • typically fueled by natural gas, propane, or diesel
  • designed to start automatically when grid power goes out and shut down when power is restored
Best Uses
  • if you live in areas with frequent or prolonged outages
  • if rely on electric heat, well pumps, or other critical electric systems
  • if you have medical or accessibility needs that make extended loss of power especially risky
  • if you want your home to function as normally as possible during long emergencies
Whole-Home Brands

Generac, Briggs & Stratton, and Cummins

Cost Range

A typical whole-home generator unit might average around $9,000, with a general range from about $4,000 to $25,000, depending on capacity, brand, and features. Installation, permits, fuel hookups, and transfer switch work are additional costs and can significantly affect the final price.

Capacity Range

Often 10,000–25,000+ watts

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How to Size a Fuel Generator for Your Needs
1. List Your Essential Devices & Appliances

Start by deciding what you must keep running during an outage - not necessarily at the same time.

Common essentials include:

  • refrigerator and/or freezer
  • furnace blower or boiler circulator (if applicable)
  • well pump (if you have one)
  • modem/router and basic lighting
  • medical devices (for example, a CPAP machine)
  • a few outlets for phone and device charging

For each item, locate its wattage (W). This is usually printed on a label, stamped on the appliance, or listed in the owner’s manual. If you see amps (A) instead of watts, you can estimate watts using: > Watts ≈ Volts × Amps (For most household circuits, that’s usually around 120 volts in the U.S.)

2.Understand Starting vs. Running Wattage

Some appliances, especially those with motors or compressors (like refrigerators, freezers, well pumps, and some furnaces), briefly draw more power when they first turn on. This is starting or surge wattage. After they’re running, their draw drops back to a lower running wattage.

When sizing a fuel generator, you’ll want to account for both:

  • what the generator must supply continuously
  • short bursts the generator must handle without stalling or tripping

Make sure your combined loads stay below both ratings. If you exceed these ratings, the generator may shut down or fail to run the appliance properly.

3. Add Up Loads and Compare to Common Generator Sizes

Next, add up the running wattage of everything you plan to power at the same time. This gives you a rough idea of the continuous wattage you’ll need.

  • Smaller sets of essentials may add up to around 2,000–3,000 running watts.
  • Once you include basics like lights, a refrigerator, and phone chargers, you’ll land closer to 3,000–5,000 watts.
  • You can also rotate loads to keep generator size and cost more manageable.

If you’re trying to power multiple large loads (such as well pumps, HVAC equipment, or many circuits at once), you may need a larger portable, standby, or whole-home unit.

4. Match the Generator Type and Size to Your Plan

Once you have a rough wattage total and a sense of your usage pattern, you can choose a generator category that fits.

Portable generators (about 3,000–5,000 watts)

  • good for running a refrigerator, lights, device chargers, and a few additional loads
  • best when you’re comfortable managing cords or using a professionally installed transfer switch

Standby generators (commonly 7,000–18,000+ watts)

  • automatically start when the power goes out
  • sized to support selected circuits such as cold storage, heating systems, and key lighting

Whole-home generators (often 10,000–25,000+ watts)

  • designed to run most or all of your house
  • best for homes with frequent or long outages, or where medical or accessibility needs make power especially critical
Tips for success
  • Add a safety margin - don’t size the generator right at your maximum calculated load. Consider fuel availability and storage (gasoline, propane, natural gas, or diesel). Think about noise level, placement, and installation requirements.
  • When in doubt - start with a realistic “critical loads” list rather than trying to power everything. A well-sized fuel generator that reliably runs your most important circuits is far more useful than an oversized unit you can’t safely fuel, store, or maintain.
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Strengths and Limitations of Fuel Generators
    Strengths
  • High power output for the cost compared to many solar-only options
  • Able to run large loads like well pumps, some HVAC equipment, or multiple appliances at once (when properly sized)
  • Work in all weather conditions, day or night
  • Standby and whole-home systems can start automatically and keep selected circuits powered without manual setup
    Limitations
  • Require a steady supply of gasoline, propane, diesel, or natural gas
  • Produce exhaust and carbon monoxide and must always be used outdoors
  • Can be noisy, which may be an issue in dense neighborhoods or at night
  • Need regular maintenance (oil changes, fuel stabilizers, testing) to remain reliable

Combining Backup Options

Fuel generators are especially powerful when combined with other backup options. Many households use a fuel generator for higher-wattage or whole-home loads during an outage, and rely on solar generators, home battery systems, or smaller battery-powered devices for quiet, fuel-free power the rest of the time. This layered approach stretches your fuel supply and gives you more flexibility for long emergencies.

Frequently Asked Questions

Is a fuel generator right for you?

  • Most portable generators run on gasoline, but you’ll also see models that use propane, diesel, or natural gas. Many modern units are dual-fuel, allowing you to switch between gasoline and propane for more flexibility in an emergency.

  • To cover essentials like lights, refrigerator, and phone chargers, a generator with at least 3,000–5,000 watts is typically sufficient. Calculate your total wattage needs before purchasing so you can match the generator to your specific situation. For a step-by-step approach to estimating your loads, see the How to Size a Fuel Generator for Your Needs section above.

  • No – never. Fuel-powered generators must always be used outdoors and away from enclosed or partially enclosed spaces because they produce carbon monoxide, which is deadly and can’t be seen or smelled. Place generators outside, far from windows, doors, and vents.

  • Gasoline generally lasts about 3–6 months without additives. With a fuel stabilizer, it may last up to about a year. Propane can last indefinitely if cylinders or tanks are stored correctly and inspected regularly. Whatever fuel you choose, rotate your stored supply as part of your ongoing preparedness routine so it stays usable.

  • Follow manufacturer instructions and local codes; operate generators outdoors, away from windows and doors; install carbon monoxide detectors in your home; never refuel a hot or running generator; and store gasoline, diesel, and other fuels in approved containers away from living spaces. These practices help reduce fire and carbon monoxide risks during an outage.

  • Both are portable, but they serve slightly different priorities. Inverter generators are quieter, more fuel-efficient, and provide clean power that’s better for sensitive electronics, but they usually cost more. Conventional generators are more affordable and better for running heavy loads for long periods, but they’re louder and tend to need more frequent maintenance. Your choice comes down to noise tolerance, budget, and the types of devices you plan to power.

  • Standby generators are connected to your home’s electrical system through an automatic transfer switch. When the power goes out, the switch detects the interruption and signals the generator to start automatically, usually within seconds. This ensures a seamless transition to backup power without any manual intervention. When utility power returns, the system switches back and shuts the generator down.

  • A whole-home generator system is permanently installed and wired into your home’s main electrical panel. It is typically fueled by natural gas or propane, so it can run for long periods without manual refueling. Working together with an automatic transfer switch, it starts up when the grid fails and can power your entire home or a very large portion of it - keeping daily life closer to normal during long outages.