How to Choose the Right Backup Generator for Your Home

In the US, power outages are more frequent than ever —about 45% of electricity customers experienced them in the first half of 2025—and the resulting outages are lasting longer. As our aging power grid struggles to cope with the increasing use of air conditioners due to rising global temperatures, not to mention the insatiable energy demands of artificial intelligence , the problem is likely to worsen: the US Department of Energy estimates that the risk of power outages will increase by as much as 100-fold over the next few years.

If you want to prevent the most serious consequences of an unstable power grid, you may need to purchase a backup generator (not to be confused with a rechargeable power station) to ensure you’ll be relatively comfortable during a power outage. But don’t just go to the hardware store and buy any generator that’s on sale. Choosing the right generator for your home and your conditions is crucial. Here are some factors to consider.

How much power should your backup generator provide?

The first step in choosing the right generator for your home is determining how much power you’ll need. This requires knowing three parameters: how long you’ll need the generator to run, how many appliances you’ll want to power during a power outage, and how much power those appliances and systems will consume.

• Duration. It’s impossible to predict the future, but you can get some information from neighbors (or from your own memory) about past power outages. Did they last several unpleasant days or were they relatively short? If the latter, you may not need a large backup power source unless you want to be prepared for anything.

• Number of electrical appliances. Consider what you’ll need to power from the generator. Will it just be a few light bulbs and phone chargers, or will you need to keep the heat running, the refrigerator running, and a storm pump running? Anything you add to this list will increase the generator’s capacity.

• Wattage. Once you’ve identified all the appliances you’ll need to run, you’ll need to add up the wattage the generator needs to produce. Most appliances list this information on the label; if not, it’s usually available in the owner’s manual or online. If the label only lists amps, you can usually multiply that number by 120 (the standard voltage in most homes) to get a rough idea.

  Add up all these watts, and you’ll get a baseline for your power needs during a power outage. Some appliances, such as a sump pump, draw more power at startup (called inrush wattage) before reducing their consumption (running wattage), so it’s recommended to multiply the baseline by 1.5 to ensure you have enough power to handle the power surges when the pump or refrigerator compressor turns on and off.

  For example, let’s say I need to power a refrigerator (600 watts), a sump pump (1000 watts), a computer, and several lights (400 watts total). That’s a base load of 2000 watts, so I’ll likely need a generator capable of producing at least 3000 watts.

Which generator should you choose: portable, inverter, or backup?

Next, you need to decide what type of generator you need: a backup generator, a portable generator, or an inverter generator.

• Backup generators are the most expensive, but also the most comprehensive, solution. They typically run on natural gas directly from your home’s water supply (although propane-powered models are also available) and are designed to turn on during a power outage. These powerful generators can power an entire home, often producing up to 20,000 watts. They’re ideal if you expect frequent and lengthy power outages or if you simply want the peace of mind of having uninterrupted power even if a storm knocks out power in your entire neighborhood. Typical costs range from $8,000 to $16,000 , professional installation is usually required, and you’ll need an outdoor location to house it.

• Portable generators are the most common and typically the most affordable. They are equipped with wheels and designed to be moved as needed. Their output ranges from 1,000 watts to gigantic models capable of generating 20,000 watts (though the word “portable” becomes somewhat vague when talking about such a large generator—for example, this model weighs 557 pounds). They are ideal for most people who simply need a power source, as well as for those who might use the generator for other purposes, such as camping or doing household chores. Typical cost: $300 to $4,000, depending on features.

• Inverter generators are similar to portable generators, but they operate much more efficiently and quietly, as they don’t operate at full power like most portable generators, but instead adjust their output based on the load they’re using. They use less fuel and last longer, and are typically mounted on wheels for easy transport—and their quieter operation also creates less interference with electronics like computers and routers. Many can produce enough power to power an entire home (usually around 5,000 watts), but they also tend to be much more expensive than what they provide. If you have the extra funds, an inverter generator is likely the better option. Typical cost: $350 to $4,500, depending on the features.

• Solar power stations. Although they’re sometimes called “solar generators” because they’re charged by solar energy, they’re not actually generators—they’re large batteries that store energy for later use. You can buy portable power stations that produce enough watts to power your entire home, or you can install larger systems that can completely disconnect you from the grid. They’re typically more expensive to purchase but cheaper to recharge. However, their main drawback is time: once a solar power station runs out of power, recharging it with solar energy alone can be difficult (and time-consuming).

What fuel will your backup generator use?

Another important factor when choosing portable and inverter generators is fuel type. As noted, large standby generators typically run on natural gas or propane. More compact portable and inverter generators offer several additional options:

• Gasoline is the most common fuel for portable and inverter generators. Gasoline is generally easy to buy, but it spoils quickly, so you can’t just leave it in the tank or store it in the garage indefinitely. You’ll need to drain the tank when you’re not using the generator regularly, and be sure to stock up on fuel (or know how to siphon it from your car ) if you think a power outage might occur.

• Propane. Generators that connect to a standard propane tank are available. Propane lasts much longer than gasoline, and you don’t have to worry about draining the tank. However, obtaining propane may be more difficult, depending on where you live. If you already use propane in your home and have a large tank on site that is regularly replenished, this may be an ideal choice.

• Diesel fuel. Diesel generators typically require less maintenance due to their simpler design and the fuel’s self-lubricating properties. As a result, these generators last longer than other models and require less attention. On the downside, diesel fuel produces a lot of smoke and has an unpleasant odor, which can be inconvenient if you don’t live near a fuel source.

• Dual-fuel and tri-fuel. If you need as many options as possible, you can purchase dual-fuel generators that run on both gas and propane, or tri-fuel generators that can also use natural gas. Of course, these generators tend to be more expensive.

Other backup generator features to consider.

Finally, a few things you might want to pay extra for:

• Electric starter. Most generators use a good old-fashioned pull cord to start the engine. If you have difficulty starting these generators or have physical limitations that make it difficult, you can find models with a push-button starter, like those found in cars, which will make life much easier. Keep in mind that this will require connecting the battery to your generator.

• Automatic Shutoff. Generators are engines, and as such, they pollute the environment. You should never run a generator inside or even too close to a house. Having a generator with a carbon monoxide detector that shuts off if it detects excessive exhaust emissions is an additional safety feature worth considering. Generators typically use oil for lubrication, so a low-oil detection feature that shuts off the generator before it can become damaged is another helpful feature.

• Outlets (or places to plug in devices). All the power in the world won’t do you much good if you don’t have enough outlets, so be sure to count them before buying.

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