Do Solar Panels Work in a Power Outage?

The lights go out in a storm, you look up at the panels on your roof, and you wonder why the house is still dark. It's one of the most common surprises for new solar owners.

The good news is that solar can keep your home running in an outage. It just needs a battery to do it. This article explains why, what a battery lets you run, and your options whether you're going solar now or already have panels. For the bigger picture, see our guide to solar batteries and backup power.

Do solar panels work when the power goes out?

Not on their own. Most home solar systems in New England are grid-tied, which means they connect to the utility's lines. When the grid goes down, a grid-tied system without a battery shuts off too, even on a bright, sunny day.

With a battery, the answer changes to yes. The system separates from the grid, runs your home from the battery, and uses the panels to recharge it during the day.

Either way, you don't have to flip anything. A system without a battery turns back on by itself once the grid is restored. Our guide to how home solar works walks through the parts of a system and how power moves between your home and the grid.

Why does grid-tied solar shut off during an outage?

It's a safety feature. When the power goes out, utility crews head out to repair the lines. If your panels kept sending electricity onto those lines, they could put the people fixing them at risk. So the system stops sending power the moment the grid goes down and stays off while the utility works to restore service. Our solar FAQ covers this under "What happens in a blackout?"

Without a battery, there's nowhere safe for that power to go. Your home is still wired to the grid, and the system has no way to power only your house while keeping the street's lines dead. That's why the panels go quiet even though the sun is shining.

This doesn't mean grid-tied solar is a bad choice. The grid connection is what makes net metering work: the extra power your panels make on sunny days becomes bill credits you use at night and in winter. That is where most of your savings come from, outage or not.

How does a battery keep solar running in an outage?

A battery gives your system a safe place to send power when the grid is down. When the outage starts, the system separates your home from the grid and switches to the battery automatically. You don't have to go to the basement or start anything.

From there, the battery and the panels work together:

• At night, the battery runs the circuits it's set up to cover.
• During the day, the panels power your home and refill the battery with what's left over.
• When the grid returns, the system reconnects on its own and goes back to its normal routine.

That daily recharge is the big difference between a battery with solar and a battery on its own. A battery by itself runs until it's empty. Paired with panels, it gets a fresh charge every day the sun is out, which is what lets a household ride out an outage that lasts several days.

What can you run on solar during a power outage?

It depends on how the battery is set up. There are two common approaches:

• Essentials backup. The battery powers a separate panel with your most important circuits, such as the refrigerator, some lights, Wi-Fi, outlets for phones and the fan or pump that runs your heat. This is the most common choice and needs the smallest battery.
• Whole-home backup. The battery can run the entire house. That takes more stored energy and more power output, or more than one battery, especially if you have a well pump, a heat pump or central air.

How long the battery lasts comes down to what you run, not just its size. Heavy loads like an electric dryer, an electric range or central air drain it quickly. During an outage, it helps to save big jobs like laundry for the middle of a sunny day, when the panels are producing.

Your installer works out the right setup from your electric bill and the circuits you want covered. The battery guide covers sizing in more detail, and if your electrical panel is older or full, our article on electrical panel upgrades for solar explains what may need to change.

How do New England storms affect solar and backup power?

Outages here come from all seasons: summer thunderstorms, fall nor'easters, ice storms and heavy snow. Connecticut's battery program even pays more to homes on the circuits with the most storm outages, a sign of how much outages matter to the state.

Season changes what a battery can do. In summer, long days refill a battery quickly. In winter, days are short and snow can cover the panels for a while, so the battery gets less of a recharge. That's when running only essentials matters most. Our article on solar panels and snow covers what happens after a storm.

Some homeowners use a generator instead, or keep one alongside a battery. A generator can run heavy loads for days as long as it has fuel, while a battery is silent, starts on its own and refills from your panels. The right mix depends on how long your outages tend to last and what you need to keep running.

What if you already have solar without a battery?

You can usually add a battery to an existing system. Your installer checks your inverter, your electrical panel and where the battery would go, then designs the backup around the circuits you care about.

Massachusetts ConnectedSolutions accepts batteries installed with new solar, with existing solar or on their own, so you don't have to replace anything to join. If you're going solar now and think you might want backup, ask for your quote both ways, with and without a battery. Doing both at once means one design, one set of permits and one installation.

Batteries we install as part of an Evergreen Solar system are covered by the same 25-year warranty as the system. Our original post on how solar panel batteries work covers the basics of what a battery does day to day.

Which battery programs pay you in New England?

A battery doesn't only earn its keep during outages. Utilities in all three states pay battery owners to send stored power to the grid on the busiest summer afternoons. Ask your installer how the battery is set up during those events.

• Massachusetts: ConnectedSolutions through Mass Save pays $275 per kW of the battery's average contribution during summer events. Batteries also qualify for the 0% Mass Save HEAT Loan, up to $25,000.
• Connecticut: Energy Storage Solutions pays an enrollment incentive plus yearly performance payments for 10 years. The Connecticut Green Bank's Smart-E loan covers batteries as well as panels.
• Rhode Island: Rhode Island Energy runs its own ConnectedSolutions battery program. If you own your solar, the state's Renewable Energy Fund grant adds $5,000 when a battery is funded in the same award.

With a lease or PPA, a battery that's part of the system can still qualify for the 30% federal credit, which lowers what you pay. If you're paying cash or using a loan, the federal homeowner credit for batteries ended for systems installed after December 31, 2025, so state programs and financing like the Massachusetts and Connecticut solar loan programs do that work instead.

Want to know what backup would look like on your home? Call us at (508) 507-2908. We'll design your system with and without a battery so you can compare.

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