Solar Backup Batteries Explained – Are Solar Backup Batteries Worth It?

Solar backup batteries allow you to store the energy that your solar panels produce. Your solar panels get energy from the sun all day long, and they store this energy in a battery for later use.

Theoretically, solar backup batteries solve the biggest problem with solar panels: you can store energy for later use. Your solar panels only produce electricity during the day, which is also the time when you use the least amount of electricity. With a solar backup battery, you can store this energy instead of wasting it or selling it back to the grid.

Solar backup batteries have surged in popularity. But are they worth it? Should you buy a solar backup battery? Today, we’re explaining everything you need to know about solar backup batteries and their value.

How Solar Backup Batteries Work

Solar backup batteries store unused electricity produced by your solar panels during the day.

Your solar panels convert sunlight into electricity all day long. Your home uses whatever electricity your solar panels produce. Then, it sells excess electricity back to the grid (assuming you have a normal, grid-connected solar system).

With a solar backup battery, any excess electricity you produce goes into the solar backup battery. Instead of being sent to the grid, that electricity gets stored in your battery for later use.

When the sun goes down, you can continue to power your home with electricity that your solar panels produced during the day. Even though the sun has gone down and your solar panels are no longer producing electricity, you can continue to use your own solar electricity – and avoid paying for electricity from the grid.

Are Solar Backup Batteries Worth It?

Solar backup batteries come in all shapes, sizes, and options. You can spend as little as $200 or as much as $15,000 to install a solar backup battery in your home.

Most homeowners pair their solar panels with lithium-ion batteries. On average, it costs $6,500 to $15,000 to install a lithium-ion battery in your home.

Alternatively, some homeowners opt for a lightweight solution: lead-acid batteries that cost under $500. However, these batteries store a limited amount of electricity. They’re best used for RVs, campers, and similar small homes – not as a power source for an entire home.

Tesla’s Powerwall is one of the best-known solar backup batteries available today. Priced at $8,500, the Tesla Powerwall is a popular option for homeowners seeking to capture the electricity produced by their solar panels. Tesla stopped selling the original Powerwall in April 2021, and the company plans to release an upgraded version called the Powerwall+ in the near future. The Powerwall+ will have similar features to the original Powerwall, although it’s expected to have higher capacity and a higher price tag (of around $10,500).

You can find plenty of other solar backup batteries sold online or in your area. The LG Chem RESU Prime, the sonnenCore, and Electric PowerPod 2 are three of the most popular solar backup batteries available today. Expect to pay around $8,500 to $14,000 to install any of these solar backup batteries.

Why Are Solar Backup Batteries So Expensive?

If you’ve invested in solar electricity for your home, then it may be worth investing in a solar backup battery. However, solar backup batteries are expensive. Although prices drop every year, solar backup batteries continue to be a large expense because of the following factors:

The Manufacturer & Brand: Like any other piece of electronics, solar backup batteries are influenced by the brand. German battery company Sonnen has carved a niche for itself in the premium part of the market, for example, because Sonnen has unique manufacturing processes and long-lasting batteries. If you buy a luxury solar backup battery from Sonnen, you could pay up to $30,000. Tesla, LG, and other major names have also entered the space, and the brand influences the price significantly.

Battery Components: The main cost of a solar backup battery lies in its components. Most residential systems use lithium-ion batteries made of nickel manganese cobalt (NMC) or lithium iron phosphate (LFP). Cheaper batteries use lead-acid, although these batteries are less powerful and don’t last as long.

Size of Battery Array: You may need to install multiple batteries for larger homes. The more batteries you install, the more expensive your solar energy system will be. The size of the battery also changes based on your needs. Depending on the number of kilowatt-hours of energy you use, the storage capacity of the battery, and other factors, you’ll need to adjust the number and size of solar backup batteries you need.

Backup Needs: If you live off the grid, then you may need to install multiple batteries to power everything in your home. If the power runs out in your first battery, you can continue drawing power from your second battery. Even if you are connected to the grid, you may want a backup battery to avoid drawing electricity from the grid. Some homeowners even install a backup load panel (for $1,500 to $2,500) to ensure the backup battery only powers critical appliances in the home.

Labor: It costs money to install a solar backup battery. It’s not as simple as plugging something into your wall. Some homeowners save money by installing the solar backup battery at the same time they install the solar panels. However, labor makes up a considerable portion of the cost of a solar backup battery. You may need additional electrical work to connect your solar backup battery to your panels.

Remember that solar backup batteries are eligible for the same 26% federal solar tax credit as solar panels, which can reduce the cost of ownership. Depending on your jurisdiction, your solar backup battery may qualify for other incentives and rebates.

Should I Buy a Solar Backup Battery?

A solar backup battery is the right choice for some homeowners but not others.

If you want to be self-sufficient and avoid relying on the grid for electricity, then a solar backup battery is crucial.

Solar backup batteries are also ideal for homeowners who live off the grid or in areas with frequent power outages.

Some homeowners also buy solar backup batteries because full-retail net metering is not available in their area. Instead of donating electricity to the grid every day, you can use this electricity yourself.

Others buy solar backup batteries to take advantage of temporary rebates and incentives. It may be the best time to buy a solar backup battery, and the battery will pay for itself more quickly because of the rebates.

However, if your primary goal with a solar backup battery is to save money, then it may not be worth the price. If your area has full-retail net metering, then you won’t save money by installing a solar backup battery. You’ll get peace of mind and protection against power outages, but you’ll spend the same amount of money (while adding thousands to your solar system installation costs).

Final Word on Solar Backup Batteries

Solar backup batteries expand the usefulness of your solar panel system. A good solar battery storage system makes it easy to utilize the electricity you produce during the day. It helps you stay safely off the grid and maintain true energy independence. It can also help you avoid blackouts, power outages, and other issues with the grid.

As solar backup battery prices continue to fall, they’re becoming more affordable for homeowners every year. Weigh the pros and cons of a solar backup battery system to determine if it’s the right choice for you.