Are you thinking about adding battery storage to your existing solar panel system? Adding battery storage to an existing solar system can be a game-changer for homeowners who want to maximize their energy savings and reduce their reliance on the grid.*

With battery storage, excess energy produced by your solar panels during the day can be stored and used later when the sun isn’t shining or during power outages. This blog will cover when and how to add battery storage to your existing solar system.

When should you add battery storage to your solar panels?

When it comes to adding battery storage to an existing solar system, it depends on your needs and also the future goals you may have for your home. Take a look at these:

Net metering and time-of-use rates

For instance, a solar battery might be the main component missing from the savings you could gain from net metering. Chat with your ADT Solar Energy Specialist to find out whether your utility provider offers net metering.

Another benefit from adding a solar battery to your existing solar energy system is taking advantage of time-of-use (TOU) rates. Under TOU rates, the cost of your electricity might vary depending on the time of day, and even the time of year. Although utility companies have different rates, costs might be higher in the evenings.

With a solar battery, you can use stored energy to power your home instead of pulling electricity from the grid when the cost of electricity is higher. Learn more about how to benefit from time of use rates with your solar panels.

Power outage protection

A backup battery like the Enphase IQ Battery can also be great for blackout protection. Whether it’s the frequent power outages that are becoming more common across the U.S., or a faulty power grid that struggles to meet the current demand, your home might need a solution when the lights go out. It’s a great idea to add energy storage to your home, so you can have a solution that keeps vital parts of your home powered1.

No matter the reason, adding a battery backup to an existing solar panel system can be easy when you know your options. Keep reading to discover the differences between each solution.

How to add a battery backup to an existing solar energy system?

You can easily add a battery backup to an existing solar energy system by choosing the right solution for your current setup. If your solar panel system is already equipped with storage-ready microinverters, you should be able to easily add a storage battery. However, if it’s not, you can choose to replace the inverters on your system through a direct current (DC) coupling or add off-grid inverters with an alternative current (AC) coupling. It all depends on your current solar system set-up and the needs of your home. Let’s take a closer look.

AC-coupled solution

An AC-coupled solution means the solar panel system already has grid-tied inverters that can be paired with off-grid inverters and then connected to a new set of backup batteries.

Here’s how it works:

  • First, solar panels take energy from the sun and produce DC power.
  • The grid-tied inverter has the job of converting DC to AC for home usage or sending excess electricity to the grid. Unfortunately, through this conversion, there is a small loss of energy.
  • Finally, the hybrid, or off-grid, inverter takes the converted AC power and converts it back to DC power to be stored in the backup battery.

The AC solution is popular because of its compatibility with many types of inverters. It also tends to be the cheaper option and most flexible when it comes to location. However, the AC solution has proven to be less efficient than the DC solution because of the loss of power through conversion.

DC-coupled solution

Another option is the DC-coupled solution. It works like this: The solar panels produce DC power, which gets sent to a solar charge controller and then to the battery. It’s as simple and efficient as that! The whole exchange occurs without having to convert the electricity to AC until it’s time to be used by your home, or sent back to the grid.

This solution is deemed as more efficient since the energy is only converted one time, and there’s little to no energy loss when getting energy to the battery. In order to use this solution, you’d have to replace your grid-tied inverters with off-grid inverters. Off-grid inverters tend to be a bit difficult to install, so they’re more likely to be more expensive than grid-tied inverters.

Replace inverters with storage-ready inverters

The final option for homeowners interested in adding a battery backup to an existing solar system is the storage-ready inverters. Homeowners can simply replace their grid-tied inverters with storage-ready inverters.

While this option works for all grid-tied systems and is the most flexible, it can also be one of the most expensive. Storage-ready inverters were created for the purpose of energy storage and often have additional features — some that don’t even require a battery. Ultimately, they function similarly to the DC-coupled solution, just with a different type of off-grid inverter. They also require a replacement of the current grid-tied inverters.

Residential clean energy credit for battery storage

Luckily, the federal government is now offering a huge incentive for adding a battery to an existing system. If you’re a homeowner with an existing solar energy system, you’ve likely heard about the federal solar tax credit.

Also known as the Investment Tax Credit, this credit allows eligible homeowners to claim a tax credit up to 30% the cost of their system — that includes the solar battery2. The Inflation Reduction Act recently updated the solar tax credit to allow for standalone batteries added after your solar system has been installed to be included in the 30% tax credit3.


It can be a tough decision when you’re considering adding batteries to your existing solar energy system. But it’s worth considering, if you’re looking to make the most of your solar investment. Think about adding battery storage to your system and start enjoying more of the benefits of clean, renewable energy.