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With the ever-present risk of power loss from weather disasters and other problems, you might be considering buying a whole-house or standby generator for your home. Understanding the available features and assessing your power needs will help you buy the right size emergency home generator to keep essential appliances running.

There are many benefits to having an effective battery backup system for your home.

Having a standby generator will give you the backup power that you need when an emergency hits and leaves you without electricity -- perhaps for a long time. Each type of generator has features like inverters that will cope with a variety of power needs, and they come in a range of sizes.

If you have a requirement to power your whole house in an emergency power outage, I have assumed that you will want to power at a minimum: a TV, fridge, computer, freezer, four lights, and a 2kW electric fireplace. That adds up to a power requirement of around 3,630 watts.

These emergency generators like to operate at 50% of maximum load, so if you want to power more energy-hungry appliances, such as a microwave, washing machine, or medical equipment, you will need to choose a portable generator that delivers more than 6,000W to ensure you'll have enough energy to run everything at once.

Whether you're new to shopping for an emergency generator or looking to upgrade what you currently have, there are several things to consider when choosing the right generator for your home and home office:

Most of the generators on this list use gasoline to run an engine which produces the electricity you'll use. There are generators available that use propane for a cleaner-burning unit, and even what are known as "dual fuel" generators that can run on either. These types of generators cannot be used indoors, since they produce dangerous fumes and carbon monoxide.

There are emissions-free, electric generator systems that can be used either inside or outdoors. You can check out our list of the best portable power stations here.

The best way to work out how high a wattage output you'll need is to make a list of essential appliances and devices you'll want to keep running during an emergency. Once you have your list, find out how many watts each item uses and add them all together. Remember that things like standard refrigerators, microwaves, washers and dryers, and space heaters can use a lot of energy; on the other hand, if you just want to keep a radio and a few lights on while charging your phones, you don't need a huge output. 

Lowe's has a handy wattage worksheet that provides average continuous run and starting wattage for tons of different devices and appliances. Keep in mind that everything that uses electricity will use a big surge of power on start-up, then level out to a much lower running output, so you'll want to choose a generator that has both an adequate continuous output and starting wattage.

Unlike permanently installed home generators, emergency backup units cannot be run indefinitely. Most standby generators have a recommended maximum continuous run-time of 500 hours. This means you can still get almost 21 full days of continuous run-time before you need to do any engine maintenance. 

To prolong the life of your standby generator, you'll want to do regular engine maintenance twice a year: once in spring and once in the fall. Doing things like checking sparkplugs, changing oil, and replacing air filters will keep your standby generator running at optimal efficiency for much longer.

Remember to never leave a running generator unattended and to never plug a standby generator directly into your house circuit without having a professional electrician install a manual power transfer switch first. Without the switch, you could burn your house down, get seriously injured, or be killed.  

A manual start on your generator gives you more control over how and when the emergency power kicks in during an emergency, which is best when the lights are flickering or cutting in and out quickly. But this also means you may be trying to pull-start your generator in dangerous conditions like high winds and lightning. There are manual start standby generators that have push-buttons rather than rip cords, which your shoulders will thank you for when you don't have to frantically yank a cable to restore power. 

An automatic start switch allows your generator to "sense" when the grid-provided electricity in your home cuts out. It will kick on, minimizing the time you're without power. These switches are best for anyone who has in-home medical equipment, like ventilators or oxygen concentrators, and cannot lose power for any amount of time. 

The All Power 9000W gasoline/propane portable generator will run using either gasoline or propane with an electric or pull cord start. Its gasoline tank has a capacity of 6.6 gallons. The generator will run for up to 10 hours of operation at half load.

Its 459cc air-cooled engine will deliver 9,000W power on gasoline and 7,250W power using propane. It uses 12,000W to start. It has an operating noise level of 76 dB.

This model has carbon monoxide (CO) sense technology, which will stop the generator and alert you when CO is detected by the system. The generator comes with wheels and handle to maneuver it easily.

The Generac 8,000W generator is a gasoline-powered generator with an electric or pull cord start. It uses its 'power rush' starting technology which uses 8,000W running power increasing to 10,000W when starting. 

The generator will run for up to 12 hours of operation at half load. It has an operating noise level of over 60 dB.

This model has carbon monoxide (CO) sense technology, which will stop the generator and alert you when CO is detected by the system. The generator comes with wheels and a handle to maneuver it easily.

The DuroMax 13,000W dual fuel generator is a will run using either gasoline or propane with an electric or pull cord start. Its 500cc air-cooled engine uses 10,500W running power, increasing to 13,000W on gasoline and 9,975W running power. It is 12,350W when starting on propane and its idle control system will reduce the engine speed when under no load.

Its gasoline tank has a capacity of 8.3 gallons. The generator will run for up to 8 hours of operation at half load on gasoline and 6 hours on propane  It has an operating noise level of over 74 dB. 

The generator is CARB compliant, and it comes with wheels and a handle to maneuver it easily.

The Westinghouse WGen 9,500W gasoline/propane portable generator will run using either gasoline or propane with an electric or pull cord start. Its gasoline tank has a capacity of 6.6 gallons. The generator will run for up to 8 hours of operation at 50% load on gasoline and 7 hours at 50% load on propane.

Its 457cc engine will deliver 9,000W running power on gasoline and 7,250W power using propane. It uses 12,000W to start. It has an operating noise level of 74 dB, and it comes with wheels and a handle to maneuver it easily.

The Honda 3,000W generator is a gasoline-powered generator with an electric or pull cord start. Its 196cc engine uses 2,800W running power increasing to 3,000W when starting and its throttle system reduced the engine speed when under no load. 

Its gasoline tank has a capacity of 3.4 gallons. The generator will run for up to 20 hours of operation at half load. It has an operating noise level of over 57 dB.

This model has carbon monoxide (CO) sense technology, which will stop the generator and alert you when CO is detected by the system. The generator has no wheels or pull along handle, but it does have two handles to lift it easily.

The Green-Power America 10,500W gasoline/propane portable generator will run using either gasoline or propane with an electric or pull cord start. Its gasoline tank has a capacity of 6.6 gallons. The generator will run for up to 7.5 hours of operation at half load on gasoline and 4.5 hours at half load on propane.

Its 479cc air-cooled engine will deliver over 8,000W running power, using 13,000W to start. It has an operating noise level of 85 dB.

This model has carbon monoxide (CO) sense technology, which will stop the generator and alert you when CO is detected by the system. The generator comes with four wheels to maneuver it easily.

The A-iPower 15,000W portable generator will run using gasoline and has an electric and pull cord start. Its gasoline tank has a capacity of 8 gallons. The generator will run for up to 7 hours of operation at half load.

Its 680cc engine will deliver over 12,000W power, using 15,000W to start.

This model has carbon monoxide (CO) sense technology, which will stop the generator and alert you when CO is detected by the system. The generator comes with wheels and handle to maneuver it easily.

The Westinghouse WGen 12,000W ultra duty portable generator will run using either gasoline or propane with an electric or remote control start. Its gasoline tank has a capacity of 10.5 gallons and has a built-in fuel gauge. The generator will run for up to 11 hours of operation.

Its 479cc air-cooled engine will deliver over 12,000W running power, using up to 15,000W to start and at peak load. It will lower its idle speed when under no load situations to optimize its fuel efficiency and extend its run time.

It has an operating noise level of 74 dB and is CARB compliant.

The Pulsar 12,000W dual fuel portable generator will run using either gasoline or propane with an electric or pull cord recoil start. Its gasoline tank has a capacity of 10.5 gallons and has a built-in fuel gauge. The generator will run for up to 11 hours of operation and can switch between fuel sources whilst in use.

Its 457cc engine will deliver over 9,500W running power, using up to 12,000W to start and at peak load on gasoline and 8,550W running and 10,800W peak load on Propane. It will lower its idle speed when under no load situations to optimize its fuel efficiency and extend its run time.

The generator is CARB compliant, and it comes with wheels and a handle to maneuver it easily.

The Champion 8,750W gasoline/propane portable generator will run using gasoline using an electric or pull cord start. Its gasoline tank has a capacity of 4.2 gallons. The generator will run for up to 10.5 hours of operation at 25% load.

Its 4420cc engine will deliver 7,000W running power on gasoline. It uses 8,750 Watts to start and has an operating noise level of 72 dB.

The generator is CARB compliant, and it comes with wheels and a foldaway handle to maneuver it easily.

We chose this selection of generators based on different requirements. All of the generators have electric starts with manual pull cord backup starting handles, all are portable, and most have wheels and a handle. Some of the generators in this list will work with either gasoline or propane, some have large gasoline tanks enabling the generator to run for longer without running out of fuel. Some of the generators have carbon monoxide alerts and safety systems.

The All Power America 9,000W is the best home generator based on its power output, price, and safety features.