(703) 686-5621

Battery Backup Basics: Your top six questions about home battery storage

This week, we volunteered at a local day camp with a Harry Potter theme. Dressed as Professor Tonks, complete with purple hair and combat boots, I showed 140 kids how a solar panel collects the sun’s energy and stores it in a battery. Then we used the stored power to make snow cones! 

It was super fun until, suddenly, thunder and lightning moved in…

We moved inside to safety, but then the power went out. Chaos reigned in the darkened church hall for a moment until the kids heard the snow cone machine continue to whir—like magic!

Because I had renewable solar energy stored in my portable solar battery, my snow cone maker kept on going; I continued to hand them out until every camper was served–and the unplanned excitement made the kids feel like it was even more of an adventure. It was a wonderful example of how nice battery backup is when the grid goes down. 

Of course, power outages are happening more often due to more intense storms caused by climate change, and the problems caused can obviously be much more dire than whether or not you can make snow cones. Already this spring and summer, we’ve experienced many outages in our region, and we have heard from you that you’re wondering how battery storage can help.  So let’s dig into how this magical battery storage works and how it might help you weather the next storm. 

Battery Backup Basics: What does a home battery system do?

A home battery is similar to a gas-fired generator in that it provides backup power when your home is experiencing a power outage—either due to a storm or a problem with the power company. Your battery is charged by your solar panels, so all of the electricity stored in your battery is clean and renewable. If the power goes out, your battery will switch on seamlessly so you won’t even notice the power is down until your neighbors come knocking, looking for freezer space. 

An important note– many people don’t realize that if you have solar but don’t have a battery, and the power goes out, your solar array immediately shuts off.  This is for several reasons, including complying with building codes and for the safety of electrical crews working on the lines. So the only way to keep producing solar energy in an outage is to add battery storage. Read more about this here

When can I use my battery?

You can, of course, use your stored electricity at any time and for any reason. But because we have net metering in our area, it doesn’t necessarily save you money to use stored energy, so we advise people to think of their battery more like a generator. 

Net Metering with Battery - Ipsun Solar


Your solar panels will first fill your battery with energy and then send the excess back to the grid. Then at night or during rainy days, you can choose whether to use grid energy or stored energy at any time. 

With net metering, when your solar isn’t producing at night or on rainy days, you’ll pull electricity from the grid instead. Over time net metering gives you credit when you produce more energy than you use, so it should all balance out. What the battery does do, however, is allow you to use more of your solar energy instead of using dirty grid energy, which is a great feeling for many people.

What does a battery backup system look like, and where does it go in my home?

One battery is about the size of a small bookcase and is usually mounted on a wall as close to your main service panel as possible. At Ipsun, we are certified installers for  Tesla Powerwall and Franklin Whole Home batteries, and Enphase batteries

Here’s a quick diagram of what these battery systems look like once installed.

Powerwall - Ipsun Solar

How does it work?

Included with the battery is a control panel, which is like the brains of the system. When there is no power going through your meter, the control panel immediately tells the battery to release power into the home.  This process is so seamless that you probably won’t even notice that the switch has been made.  Unlike a noisy, smelly generator that burns fossil fuel, your battery will silently provide you with clean, renewable energy until your power is restored. 

Is it complicated to install?

Each home is unique, and some jobs are more complicated than others. Luckily, we are one of the only installers in the mid-Atlantic region certified for all Franklin WH, Enphase and Tesla Powerwall— and with the most experience installing them. Our battery specialists, a dedicated team of battery-specific electricians, are the most up-to-date on current specifications and installation methods and are in constant contact with Enphase, Franklin WH, and Tesla to ensure the most effective system for your needs. 

Battery Install Team

How much power does a battery hold, and how long will it last?

Each battery component holds anywhere from 3.6 KWh to 13.6 kWh of electricity, but how that translates into available power for your home is dependent on your energy usage and other factors.

For a typical day’s worth of electric use, the US average is 28.9kWh for the whole home. If the grid is down, but it’s sunny out, your solar panels will continue to fill your battery with solar energy, so it’s not as important to conserve at that moment.  But if your solar panels are not producing due to clouds or night, it’s good to think about what your most important electrical loads are in your home and plan accordingly. Typically, our customers like to back up these five important loads:

  • Lights and outlets
  • Refrigerator
  • Wifi
  • Well pump and/or sump pump
  • Gas Furnace Blower

We like to say; just because a battery system can power the whole home during a power outage does not mean it should run everything as normal.  Larger loads such as air conditioning and electric heat can drain even large batteries in just a few hours. That is why we pair every battery installation with a Lumin Smart Panel to help automatically turn off energy-hungry items in the house to keep the critical loads running as long as possible.

Lumin Smart Panel App

Lumin Auto Load Shed - Ipsun Solar

Larger Homes with 2+ Main Service Panels

It’s important to note that each battery system will only back up one main service panel.  If your home has two or more main service panels, we recommend learning more about what is possible here.

Have more questions? Reach out to us anytime!

We love talking about solar and storage (and solar snow cones!) with you. Give us a call any time at 703-249-6594 or click below to get in touch!

Share the Post:

Related Posts