Installing solar batteries for your home is a great way to get a little extra out of your home’s solar panel system. It will help keep your essential loads running when the electricity grid goes down. But they do come at a cost.
There are a few things to consider before you install a battery backup with your solar system. In this blog, we cover the essentials to ensure you have a successful battery installation.
Here’s what is covered in this guide:
- Common Misconceptions
- Off-Grid vs. On-Grid
- Are Batteries Right for You?
- What to Ask Your Solar Installer About Batteries
- When to Install Solar Batteries
- Battery Cost & Incentives
- How to Size a Battery System
- Battery Performance and Degradation
- Battery Lifespan
- Maintenance for Batteries
- Battery Installation Tips
- Recommended Battery Brands
- Energy Storage Alternatives
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Home Solar Battery Common Misconceptions
We’ve noticed two main misconceptions about solar battery backup for homes. Those are:
One or two batteries will backup their entire house and it will only cost a few thousand dollars to do so.
Unfortunately, neither of these is true. Most home battery banks only back up a handful of appliances and devices for a limited amount of time. While it’s possible to install enough batteries for your entire home, this would be extremely expensive ($100,000 to $200,000 or more, depending on the number of loads).
That said, installing batteries for energy backup can still be a great way to guarantee you’ll have enough power for the essentials.
Grid-Tied vs. Off-Grid
There are two types of solar energy systems: Grid-tied and off-grid.
Grid-Tied Solar Systems: This is where your home and system are connected to the electricity grid. You still have access to utility-generated electricity.
Off-Grid Solar Systems: With this type, you’re not connected to the electric grid. All power is sourced independently.
How does this relate to batteries? With a grid-tied system, batteries are an optional add-on that fills the gap when the power goes out. When your solar panel system stops generating electricity (like at night), you can pull electricity from the grid. This is the type of system most homes and businesses have.
With an off-grid system, you’ll only be able to use the electricity you generate through a solar system, wind turbine, or generator. In this case, a much larger (and more expensive) battery system is common and supplemented by other power sources, like generators.
Are Home Batteries Right for You?
A battery system is an added expense, and you’ll want to make sure it’s money well spent. Consider the following questions to determine if battery backup is right for you.
Which loads do you want to back up?
Are you looking to back up select essential devices and appliances for a few hours when the grid goes down, or are you looking to back up your entire home for several days?
What’s your budget?
A battery backup system can range from $20,000 to upwards of $100,000.
What are your desired benefits?
Battery energy storage can be linked directly to your solar system for quiet, emission-free backup energy. In emergencies, you’ll have reliable backup power without having to source natural gas or another type of fuel. That said, gas-powered generators are more affordable.
What to Ask Your Solar Installer About Batteries
Each solar energy system is unique, and your battery system is no exception. It will be sized to best fit your needs. When discussing it with your installer, coming prepared with the right information is helpful. Be prepared with the following information:
- A list of loads you’d want to back up.
Unless you can drop some serious cash, you’ll have to prioritize which loads your battery system will back up. Create a list of devices and appliances you’ll want to run on your battery when the grid goes down. Rank them from most important to least essential - A list of your current equipment.
You’ll need to talk with your solar installer about how the new battery system will integrate with what you already have. Consider integration with any current generators you may have, existing solar equipment (like inverters), and EV chargers. You’ll also want to ask if you’ll need load control systems.
When is the Best Time to Install Home Solar Batteries
There are three main scenarios for installing solar batteries.
- Installing them alongside a new solar system.
It’s always the most cost-effective to install everything at once. You’ll only have to pay for certain things once instead of twice. However, it will require a larger lump sum. - Installing a new solar system with the intention to install batteries a few years down the road.
You may prefer to wait a year or two to install batteries to your solar system. In this case, consider installing solar equipment that will easily integrate with a battery. If you want to install batteries beyond that (3+ years), hold off on battery-integrated equipment and take advantage of newer technology that will likely be available when you decide to install batteries. - Installing them to an existing solar system already installed on your property.
If you’ve had solar for years and are looking to add a battery system, you should be able to retrofit your system to accommodate this. It may require replacing your inverter or adding additional equipment.
Home Solar Battery Cost & Incentives
At Paradise Energy, our home battery systems start around $20,000. Adding additional batteries will cost around $14,000-$15,000 each. The largest system we’ve installed featured 12 batteries, which came in at around $115,000.
However, government-backed incentives help reduce costs. Batteries are covered under the federal government's 30% Solar Investment Tax Credit, along with your solar system installation costs.
State incentives for energy storage are rare. That said, one state is leading the change with a state tax credit for energy storage—Maryland. If you’re installing an energy storage system in Maryland and pay state taxes, you could qualify for this incentive.
How to Size a Battery System?
The size of your battery system is heavily dependent on your specific needs and wants. Every home has different loads that require varying amounts of energy to run. They also value those loads differently. One home may consider HVAC essential, whereas others are okay to do without in an emergency.
A good way to get an accurate estimate of battery system size is to identify essential loads and then measure how much energy they use. At Paradise Energy, we’ll hook up devices on your breaker panel to measure how much energy your essential loads are using. That information will then inform us when designing your battery system.
Battery Performance and Degradation
Degradation is an unavoidable part of any battery, from the ones in your smartphones to the ones that back up your home. Over time, the amount of energy your battery can store will slowly decrease. A battery may store 10 kWh of energy when it’s installed, but after 10 years, its storage capacity could be more like 7 kWh.
The good news is most battery manufacturers guarantee degradation rates, ensuring the battery doesn’t lose its capacity too quickly. Most warranties are between 10 and 12 years and guarantee that the system holds 70-80% of the original capacity. That breaks out to about 2% degradation each year.
Battery Lifespan
Batteries won’t last forever and will eventually need to be replaced. Most manufacturers guarantee their batteries for 10 to 12 years. That said, the same manufacturers say most batteries could last 15 to 20 years, extending beyond their warranty period.
Maintenance for Batteries
Most lithium-ion batteries are maintenance-free. There shouldn’t be any regular upkeep needed on the part of the owners. You’ll also have access to system monitoring which can help tee you off should something go wrong.
In short, adding batteries to your solar system shouldn’t add much in the way of additional complications or maintenance.
Home Battery Installation Tips
Where can you install your battery system, and do you have room for them? There are a few considerations you should make regarding where you locate your system.
- Inside or Outside
Your batteries can be installed inside or outside, though inside is often favored. If you opt for outdoor installation, ensure that your area’s climate falls within the manufacturers’ warranty temperature range, or else you could lose out on that protection. You’ll also need to store them out of direct sunlight. All in all, a garage or basement is best—an area where they’re out of the way and in a temperate environment.
- Space
One battery and inverter will take up about 6’x6’ of wall space. If you’re installing more than one battery, you’ll have to size up to accommodate. Some batteries can be installed on the floor to avoid using wall space
Recommended Battery Brands
There are three solar battery brands we currently recommend for energy storage: SolarEdge, Enphase, and Franklin Whole Home. They’ve earned their place on our list because they embody the following or are working towards it:
- They have proven track records in the industry.
- They offer flexible products that can scale up or down depending on what size system you want.
- Their products are competitively priced and offer great value.
- They integrate well with other systems, like EV chargers and load controls.
- They’re lithium-ion batteries that are more power dense, last longer, and require minimal maintenance.
- The manufacturers offer batteries, inverters, and interface units so everything integrates together seamlessly.
- They offer great warranties.
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- SolarEdge Home Battery Warranty:
- 10 years
- Unlimited cycles
- 70% of original capacity at end of warranty
- Enphase IQ Battery Warranty:
- 10 years or 7,300 cycles
- 80% of original capacity at end of warranty
- Franklin Whole Home:
- 12 years or 43 MWh (about 3,161 cycles)
- 70% of original capacity at end of warranty
- SolarEdge Home Battery Warranty:
Energy Storage Alternatives
While they are a great source of renewable energy backup, batteries aren’t for everyone. They’re not required to go solar, and there are other options.
- Grid Backup
All grid-tied systems will be able to draw energy from the electric grid as long as the grid is working. In the event of a power outage, you will be without power. But you won’t have to invest any extra money in a storage system. If you live in an area with net metering, the grid will basically act as free energy storage, giving you a one-for-one trade for any electricity you upload to the grid.
- Generator
While it is noisier and does require fuel, backup generators can be a great option for backup power. They’re less expensive than a battery-based energy backup system and will keep your essential roads running while the grid is down.
Are Solar Batteries Worth It?
Solar batteries are a significant investment. But if having clean, reliable backup power is a high priority for you, a properly sized home solar battery system could be a great investment.
Our team of battery experts is ready to provide you with an exact quote for a system that best fits your needs. Don’t hesitate to contact us.
You can also browse our library of battery videos and blog posts or learn more about what size system you’d need with our free battery price calculator.
Last updated: June 2023
