Six tips for buying a solar-powered battery

Thinking of getting a solar-powered battery for your home or business? Here’s six tips to help you figure it all out.

Solar-powered batteries can let you keep — and use — all of your solar energy

Depending on its size, a battery storage system installed at your home or business stores all that extra solar energy you make during the day. When the sun goes down, you use the energy from the battery, not the utility.

Solar-powered batteries can keep your power on during an outage

A solar-powered battery lets you keep your most important appliances and lights running during a power outage. That’s becoming more important for people since this year.

Solar-powered batteries are getting cheaper and better

It’s really cool — and it might make sense for you. The utilities are increasing evening rates, a Solar Rights Alliance-backed rebate for solar-powered batteries is about to relaunch, and in some cases you could also be eligible for a healthy tax credit on top of the rebate.

But as always, it pays to do your homework before making the investment.

1. Figure out if you are affected by the new “Time of Use” evening rates

Recently, the utilities began raising rates in the evening, so that they are higher than daytime rates. If the increased evening rates will significantly affect your electricity bill, this might be a good time to look into batteries.

However, higher evening rates may not affect you much. For example, if you purchased your solar before 2016, you may not see any change in your evening rates for twenty years (check with your installer if you’re not sure).

And, if you don’t use a lot of electricity in the evening, the evening rate increase may not affect you much. Check your monthly statements and annual true-up statement and see if there is a change.

2. Determine if you are eligible for the state and federal incentives

State rebate

California offers a rebate of around 25% of the cost of a battery storage system. The incentive will cover between 85% and 100% of the system if you are low-income or require extra medical care, especially if you live in a fire-prone area of the state.

If you are buying a battery for your daily energy use, not as a backup, you are likely eligible for this rebate. Your installer will typically handle the rebate paperwork (see more below on this). Really nerdy details here.

(Shameless plug: this rebate was set to expire and the utilities lobbied furiously to keep it that way. Solar users and our allies in the solar industry overcame the utilities with a fierce campaign. There truly is strength in numbers! Join Solar Rights Alliance now.)

Federal tax credit

You may also be eligible for a federal tax credit. This will be 30% of the cost of a battery system through 2019, step down to 26% in 2020, and keep stepping down and ultimately disappearing unless Congress renews the credit.

If you install batteries with solar at the same time, you are mostly likely eligible for this credit. If you are simply installing batteries, you are eligible only if your battery system is 100% charged by your solar panels. If you do not have an income, you may not be eligible for this credit. Learn more about how to claim the Federal ITC

3. Determine if you are OK with resetting your Net Metering rate. 

If you are on the pre-2016 Net Metering rate (NEM1) and you install a battery, your Net Metering rate will reset to the current one (NEM2). That’s thanks to utility-industry lobbying.

Our take: If you have a battery, you won’t rely on Net Metering as much anyway. Instead of flowing to the utility and coming back as a credit, your extra solar energy will go into the battery for you to use at night.

Of course, you should make a decision you are comfortable with. A good installer should prepare an estimate that compares your electricity bill before and after batteries, with the different rates in mind.

4. Noodle around the internet to get a sense of what kind of battery products are out there

Check out the websites of some of the leading battery installation companies. The California Solar & Storage Association has a rundown of different products.

FYI, Solar Rights Alliance does not provide product endorsements.

5. Get an estimate from three installers

If you already have solar and were pleased with the work your installer did, give them a ring and ask if they also install battery systems. If they do, have them come out and give you an estimate.

But even if you’re inclined to use your original installer, we still recommend that you always get a total of three bids for any job. It is a little more work, but will give you more options to work from.

Refer to our “Six Tips for Finding a Solar Installer” for finding your three installers to get a bid from. Look for an installer that either has experience with battery storage, or has been doing solar installations for awhile.

6. Expect some delays and complexity

Barry Cinnamon, owner of Spice Solar in Campbell and host of The Energy Show podcast says that installers should provide accurate estimates for the installation of a battery storage system and prepare customers for some possible uncertainties:

  • Delays: The utilities often slow-walk the process of interconnecting your new storage system to the grid. And the state is often slow in cutting your storage rebate check. 
  • Electrical wiring issues: Wiring the backup subpanel and connecting some of the parts to your electric panel can be tricky and expensive depending on the location of circuits in the house and the age of your electric system. Installers should provide an accurate estimate for this work.
  • Your payback period: Remember that your energy habits may change over time, and your installer’s estimate relies on your current habits. 

Got other tips and advice to share with your fellow solar people? Send us a tip to info@solarrights.org.

More reading

California Solar & Storage Association: Comparing Back-Up Power Options