Home batteries vs. generators: Which is right for you?

Historically, most people looked to propane, diesel, and natural gas-powered home generators for resilience during power emergencies. But these days, homeowners are increasingly choosing a home backup battery instead, a cleaner alternative for that same peace of mind.

Solar battery storage systems offer many of the same backup power functions as conventional generators but can run on clean energy instead of fossil fuels.

We compare the costs, fuel sources, size, and maintenance requirements of battery backup options compared to conventional generators.

There are two primary reasons that homeowners have historically opted for generators as a backup solution: They cost less upfront and, in the past, they've been easy to find and set up. You can frequently buy backup generators at home improvement stores, and some might not even need to be installed by an electrician. 

But generators aren't perfect. And batteries are increasing in popularity.

Generators are the way of the past

Backup generators come with several downsides. For one, you have to ensure you have the fossil fuel they require, which can be problematic during unexpected outages.

Backup generators are also large, loud machines that shouldn't run every day and require regular maintenance, meaning you only benefit from having them in the event of an outage.

Finally, and perhaps most importantly, backup generators cause significant local pollution by burning fossil fuels, not the least of which is carbon monoxide, which has become a considerable safety risk with fossil fuel-powered backup generators. 

Are batteries the future?

Batteries aren't perfect. They're more expensive upfront and require an electrician to install. But, they solve most of the issues that can sometimes plague backup generators.

When you pair batteries with solar panels, the sun powers them, keeping them charged as long as the sun keeps shining. Also, batteries are eligible for incentives like tax credits and rebates, which can significantly lower those upfront costs.

Finally, there are no local emission concerns with solar plus storage installations. They run entirely on clean, renewable solar power.

The amount you'll pay to get backup power at your home or business depends on the power you need and your chosen equipment. Many standby generator options in the $2,000 to $7,000 range can power a standard American home. But the average generator cost, including installation, is $9,000. 

By comparison, a 10 kilowatt-hour (kWh) home backup battery costs about $8,000 after incentives. If you want whole-home power, you'll probably need more storage than that, though.

Altogether, you can expect to pay anywhere from $8,000 to over $40,000 to install a battery backup system depending on your energy needs. If you use a lot of electricity, you'll need to buy a bigger generator or more batteries, and you can expect the installation cost to add thousands more to your total price tag.

The average net upfront cost of a solar-plus-storage system is around $28,879 based on the following calculation:

$29,926 (11 kW solar panel system) - $8,978 (solar tax credit) + $11,330 (10 kWh battery) - $3,399 (battery tax credit)

Total cost over 20 years: Solar + storage vs. natural gas generator

Table sources: EnergySage, U.S. Energy Information Administration, Forbes