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A home generator provides an on-demand source of power in the event of a utility grid failure. While more costly to purchase and install, a standby generator eliminates the setup and headaches associated with the use of a portable generator—such as regular refueling, running many feet of extension cords, and listening to the constant hum of the engine.
Home generators vary in type, size, watts, and fuel source (either propane or natural gas). Based on the amount of power you need and your installation requirements, you can decide on the generator that is right for you. A portable generator is cost-effective and best for keeping essential items up and running, but the most power comes from a whole home generator. These larger, permanently installed generators are capable of sustaining appliances, central heating or cooling systems, lights, devices, and more. Keep in mind that standby generators should always be installed with a transfer switch to prevent back-feed that can cause harm to your home’s electrical system, the generator, or serious injury and death to utility workers.
Here are the top home generators for maintaining essential functions during a power outage.
Best Overall: Generac Guardian 24kW Standby Generator, Model 7209
Dimensions: 48 x 25 x 29 inches | Weight: 514 pounds | Material: Aluminum | Power Output: 24,000 watts (LP)/21,000 watts (NG) | Fuel Type: Propane or natural gas | Warranty: 5 years
Largest air-cooled generator available
Quiet weekly self-test mode
Significantly lower power output when using natural gas
Transfer switch is not included
Air-cooled generators are the typical choice for backup residential power. This type of generator offers simple maintenance and affordability. The Generac Guardian 24kW is the largest air-cooled generator available, providing up to 24,000 watts of power when connected to a propane fuel supply. Homeowners looking for a generator that can handle increased power demands will appreciate this capable unit. It also offers Wi-Fi capabilities so you can keep tabs on the unit’s operation from anywhere.
This popular generator model maximizes power output but minimizes space requirements. The housing of the unit is 4 feet long and 2 feet wide, which is larger than the most compact generators available but on par with typical whole-home generators. Generac also equipped this unit with a Quiet-Test weekly self-test mode that operates at just 57 decibels. During regular operation, the generator is rated for 67 decibels, which is average operating noise but impressive for a generator of this power capacity. Keep in mind that this model doesn’t include a transfer switch, so you’ll need to purchase that separately.
Best Budget: Generac PowerPact 7,500 Watt Standby Generator, Model 69981
Dimensions: 36 x 27 x 25 inches | Weight: 280 pounds | Material: Aluminum | Power Output: 7,500 watt (LP)/6,000 watt (NG) | Fuel Type: Propane, natural gas | Warranty: 3 years
Includes 50-amp transfer switch
Uses 1.42 gallons of fuel per hour
No engine hour meter
Lacks Wi-Fi monitoring
A basic but well-equipped home generator, the Generac PowerPact is an excellent budget buy. Designed to serve as a backup generator for the most essential appliances, this model includes an automatic transfer switch that can cover up to eight circuits. It supplies up to 7,500 watts of power when using propane but can also operate on natural gas—however power output is limited to 6,000 watts.
As expected for a bare-bones generator, this model doesn’t have the ability for Wi-Fi monitoring. It also lacks an engine hour meter, but an aftermarket meter can be installed to help you keep up with routine oil changes and maintenance. To make maintenance and repairs easier, three sides of the aluminum enclosure are removable.
Best for Small Homes: Cummins 13 kW QuietConnect Home Standby Generator, Model RS13A
Dimensions: 34 x 36 x 27 inches | Weight: 479 pounds | Material: Aluminum | Power Output: 13,000 watts (LP)/12,000 watts (NG) | Fuel Type: Propane, natural gas | Warranty: 5 years
Only requires an 18-inch clearance from house
Uses 2.2 gallons of fuel per hour
Lacks ability for a cold start
Choose the Cummins QuietConnect Home Standby Generator if you’re looking for a well-equipped but quiet model to keep your small house operational during a power outage. This dual fuel generator offers up to 13,000 watts of power and can be manually started or paired with a transfer switch for an automatic start.
True to its name, this home standby generator features a sound-insulated enclosure and operates at 65 decibels or less. This means it’s about as loud as normal conversation and slightly quieter than a hairdryer. Like some other small generators on the market, they can be installed with just 18 inches of clearance from the house. The low noise levels ensure that this generator won’t be a nuisance to you or your neighbors when in use.
Best Standby: Champion 12.5-kW Home Standby Generator with 100-Amp Transfer Switch
Dimensions: 52.4 x 33.5 x 32.1 inches | Weight: 520 pounds | Material: Steel | Power Output: 12,500 watts (LP)/11,000 watts (NG) | Fuel Type: Propane or natural gas | Warranty: 10 years
NEMA 3R outdoor-rated transfer switch
Gullwing enclosure for easy maintenance
Battery tender to prevent dead batteries
Must buy batteries separately
Fuses not easily accessible on the switch
A standby generator is ready at a moment’s notice to keep important systems running during a power outage. The Champion 12.5-kW Home Standby Generator is equipped with a NEMA 3R outdoor-rated 100-amp transfer switch that covers 12 circuits. Instead of setting up a portable generator and plugging in a network of cords in the aftermath of a power failure, this generator will automatically keep appliances and systems you deem most important running. It can handle up to a 4-ton AC system.
Regardless of what climate you live in or what season it is, this standby generator is equipped with a 24-volt starting system rated for use in temperatures ranging from -22 to 104. A battery tender ensures that the onboard batteries will always be ready to provide starting power. Take note that you’ll need to buy the batteries separately.
Best Portable: WEN GN6000 Portable Generator
Dimensions: 23.2 x 16.9 x 17.2 inches | Weight: 129.7 pounds | Material: Not available | Power Output: 6,000 watts | Fuel Type: Gasoline | Warranty: 2 years
Transfer switch-ready with a NEMA L5-30R outlet
7.5 hours of runtime at half-load
Gas tank only has 3.4-gallon capacity
A bit noisier than expected
For short-term and limited power needs, you can use a portable generator for your home. The WEN GN6000 is a great option since it offers up to 6,000 surge watts of power and 5,000 running watts of power. That’s enough to keep an air conditioner, television, sump pump, and lights running simultaneously. It might not be enough power to keep major appliances or a central cooling system operational, but it will help to make short power outages more bearable.
The WEN GN6000 stands out among portable generators for being transfer switch-ready, thanks to a NEMA L5-30R outlet. It has plenty of other outlets, too—including two 120V household outlets, a single 120V 30A RV receptacle, a 12V DC outlet, along with the previously mentioned 120/240V four-prong outlet. With a half-load, you can expect this portable generator to run for up to 7.5 hours before it’s time to refill the 3.4-gallon gas tank.
Best Battery: Goal Zero Yeti 1500X Portable Power Station
Dimensions: 19 x 14 x 14 inches | Weight: 43 pounds | Material: Not available | Power Output: 1,500 watts | Fuel Type: Not applicable | Warranty: 24 months
No fumes; can be used indoors
Requires recharging every 3 to 6 months
Lithium-ion batteries have limited lifecycles
For an alternative to conventional home generators, consider using a portable power station. The Goal Zero Yeti 1500X is equipped with a lithium-ion battery that can store up to 1,500 watts of power. While you might think that a portable power station lacks the juice to keep your home up and running in the event of a power failure, this top-of-the-line version from Goal Zero has enough power to operate a refrigerator for up to 28 hours. Charge it up by connecting it to a solar panel, wall charger, or 12V car charger.
The Goal Zero Yeti 1500X isn’t equipped to replace a whole-home generator, but it can serve as a short-term power supply. There are no fuel gauges to monitor, maintenance to perform, or exhaust fumes to worry about. In the event of a power failure, plug your most important devices and appliances into the outlets of the Yeti 1500X, which includes a pair of 120V AC outlets or USB ports.
Best Backup: Generac Guardian 10KW Home Backup Generator, Model 71710
Dimensions: 48 x 25 x 29 inches | Weight: 338 pounds | Material: Aluminum | Power Output: 10,000 watts (LP)/9,000 watts (NG) | Fuel Type: Propane, natural gas | Warranty: 5 years
Quiet weekly self-test mode
Equipped for Wi-Fi monitoring
Transfer switch is not included
Unit relies on Wi-Fi too much
If you want nearly instant power restoration for key systems in the event of a power failure, install a backup generator like the Generac Guardian. This 10kW model offers Wi-Fi monitoring and is equipped for either natural gas or propane fuel sources. Pair it with a 100-amp, 16-circuit transfer switch or a 200-amp smart switch, depending on your needs.
Weekly self-testing by the Generac Guardian Backup Generator ensures that it’s ready to supply power to the most important systems of your home. This model conserves fuel and operates quietly, thanks to a short five-minute test cycle that operates at just 57 decibels.
If you're looking for a well-equipped generator for your most commonly used appliances and conveniences, the Generac Guardian 24kW Home Generator (view at AP Electric & Generators) is a great option. It offers the most power of all residential air-cooled generators and can be remotely monitored using Generac's Mobile Link Monitoring System. For a budget-friendly option, consider the Generac PowerPact 7,500 Watt Generator (view at Northern Tools). Power output is significantly reduced, but it can keep up with essential items in the event of a power failure.
What to Look for in a Generator
The watts produced by a generator measure the power the unit will have available to operate whatever is plugged into it. This is one of the most important things to know about any generator you’re considering.
To know how many watts you’ll need in a generator, add up the wattage of the appliances or equipment you’re most likely to simultaneously operate. This will give you an idea of the load that your generator will need to be able to handle.
Pay attention also to starting watts versus running watts. Many appliances require a larger surge of power during start-up compared to their running energy consumption. If you don’t factor in the starting watts, you may overload the generator as you start up appliances or other items. Generally, you only need to add in the highest starting wattage to your total watts required—since you likely won’t be starting every appliance or device on your generator simultaneously.
Increased watts of power will generally equate to an increased cost when shopping for a generator, but it is better to have adequate power than to be left in the dark or have to decide between running your refrigerator or keeping cool with a fan.
Home generators require space for installation, so factor in the size of any model you're considering. The size of a generator ranges from compact units with a footprint less than 3 feet long to large liquid-cooled units that measure 5 feet or more in length. As a general rule, the more power capacity, the larger the generator will be.
Also, keep in mind that model specifications and local codes may dictate how much clearance is required between the generator and your home. Some small generators require as little as 18 inches of clearance.
Generators generally are powered by one of three fuel sources—gasoline, natural gas, or propane.
Gasoline-powered generators are the most common but also carry special cautions related to exhaust fumes and carbon monoxide poisoning. Always make sure to operate a gas generator outside of any enclosed structure (including your house or garage) where there is adequate ventilation.
You’ll also need to take measures to keep gasoline stored properly for long periods of generator inactivity. A fuel stabilizer is one method of ensuring that the gasoline in your generator remains ready for use.
Propane and natural gas are more commonly used for larger home standby generators. These fuels are generally also considered to be cleaner burning sources of fuel and provide an on-demand source of power.
Alternatives to fuel-powered generators are solar or battery-powered models. The capabilities and run times of these machines vary greatly, but they may be the right match if you have more minimal power needs. Many battery-powered generators are also a safe indoor alternative for a supply of power.
The investment you make in a generator is often backed by a manufacturer’s warranty. Most residential portable and inverter generators are protected by a two- or three-year warranty period that covers parts and labor. Standby generators, which are generally a larger investment, usually offer three- or five-year warranty periods.
Some warranties will also cover travel costs for a technician to come and service the generator, but this varies by manufacturer and model so read the fine print closely to see what will be covered in this regard.
Decide which type of generator is best for your needs: a standby (or backup) generator or a portable generator. For whole-home generators, a standby generator is the most common option since it offers power outputs between 10,000 and 24,000 watts on average. This type of generator is permanently installed outside the home and is connected to a propane fuel tank or natural gas line. With the addition of a transfer switch, standby generators are ready to supply power for a few hours or a few days or more thanks to a readily available fuel supply and high wattages. Within standby generators, you'll find air-cooled and liquid-cooled models. Residential homes with average power needs will be served well by an air-cooled unit, but in hot climates, a liquid-cooled generator may be a better choice. In addition, liquid-cooled generators generally offer a quieter operation.
Portable generators are temporary backup power solutions. They typically operate using gasoline as their fuel source. For this reason, it’s crucial that you never operate a portable generator inside an enclosed space—including your house, garage, or shed. This type of generator is best suited for powering an appliance or two and smaller tools or electric-powered items, like fans or lights. The higher the watts of the generator, the more load it can support. In general, portable generators will make life more bearable but won’t support all the creature comforts you may be used to during a power outage—such as a central air conditioning system, water heater, and other large appliances. Inverters are another type of portable generator that uses less fuel and offers quieter operation but has a higher price tag.
Some whole home generators will automatically kick in when the power goes out. This automatic start feature enables the generator to start supplying power to your home’s electrical grid without the manual start-up process often associated with portable generators.
Having a generator with an automatic start function may be especially valuable if you travel for long periods of time or have a second home. The peace of mind that comes with knowing your generator will automatically step in to keep vital systems functioning (like a sump pump and heating and cooling system) is worth the higher price tag that often comes with these systems.
Note that this isn’t the same thing as an electronic start, which is the ability to start your generator with the push of a button rather than the recoil start typical of most small motor machines. In the case of a generator equipped with an electronic start, you’ll still need to manually start the generator to begin the flow of power.
If your plan is to be able to use your generator to power hardwired appliances, then look for a machine that can be installed to work with a transfer switch. A professionally-installed transfer switch will safely disconnect your home from the power grid and supply power from your generator to designated circuits on your home’s electrical grid.
Never plug your generator into a standard electrical outlet—doing so can create electrical hazards, including back feed that can endanger utility workers that may be repairing power lines.
How do you safely run a home generator?
A whole-home generator needs to be connected to a transfer switch—which will disconnect your circuit panel from the electrical grid before allowing power to flow from the generator through the circuits. Unlike portable generators which require you to manually initiate the power transfer, home standby generators equipped with automatic start and connected to a professionally installed transfer switch can make the transition happen seamlessly and usually respond within 10 to 15 seconds of a utility power failure.
Portable generators require different safety precautions, including the often-repeated advice to never operate the unit inside of the home or garage. You should also never plug hardwired appliances into a portable generator or plug your generator into a standard electrical outlet. If you want to supply power to hardwired appliances, invest in having a transfer switch professionally installed by an electrician. You’ll need to manually flip a few switches to safely take your home off the power grid and switch to the generator’s power source, but this is the only safe way to supply power from a generator to your home’s electrical circuit and hardwired appliances.
Where is the best place to put your home generator?
Since home generators produce exhaust fumes that contain carbon monoxide, choosing the right installation spot is important for health and safety reasons. Because of this, local codes and utility companies will typically dictate placement requirements. Generally speaking, however, a generator should be installed at least 5 feet from windows and doors. Some generators can be installed as close as 18 inches to the house, but you'll still need the 5-feet of clearance from air intake locations on the house.
Portable generators should never be used indoors, including in a garage. Even with doors and windows open, the fumes can be dangerous. Instead, this type of generator should be positioned outside of the home with sufficient clearance from doors and windows. Typically, 20 feet or more is recommended. Extension cords are used to supply power to the appliances and devices you want operational.
What regular maintenance should be performed on a home generator?
The manufacturer of any generator you purchase should provide basic maintenance information, but in general, it’s recommended that you do the following for most models of generators.
- Perform a weekly self-test or run the generator for at least 30 minutes once per month. Most whole-home generators feature an automatic self-test cycle that runs for 15 minutes or less each week. For portable generators, you'll need to run the system manually. Doing so will keep the motor and components from seizing up and becoming prone to breaking or failure. Make sure that you only operate the generator in a well-ventilated, open area—even during these short maintenance runs.
- Add fuel stabilizer to the tank when storing a gasoline-powered generator for an extended period. This additive will help ward off corrosion, rust, and sediment. Gas that has gone bad is a leading cause of small engine failure, so don’t neglect proper fuel storage.
- Regularly repair or replace motor components that are subject to wear and tear. Items like spark plugs, air filters, fuel filters, and more can become worn over time.
- Never let the oil run low in your generator and perform regular oil changes. Doing so can cause major engine damage or even failure of the motor. Monitor oil levels and replenish as necessary. Many standby generators have a meter for engine hours, so you'll know when it's time for an oil change.
Why Trust The Spruce?
Erica Puisis has been covering home appliances and tools that make everyday life easier. With experience investigating the best home generators and portable generators and developing buying guides that help consumers make informed choices, she is familiar with the features that matter and the brands that offer reliable performance. To find the best home generators for this list, she considered factors like power output, size, fuel type, and cooling system. Most of the generators on this list are whole-home generators, but portable and battery generators are included for short-term supplementary power needs.