Key Takeaway
It depends on your system. A grid-tie system shuts off during a brownout, even when the sun is out. A hybrid system switches to its battery and solar, usually so fast the lights barely flicker. An off-grid system doesn't notice at all, because it was never connected to the grid.
Why does a grid-tie system turn off during a brownout?
This catches a lot of people off guard. You have panels on the roof, it's a sunny afternoon, the power goes out, and your house goes dark anyway.
It's on purpose. When the grid goes down, linemen go out to fix the lines. If your inverter kept pushing solar power into those lines, it could hurt someone working on them. So grid-tie inverters are built to detect the outage and shut off within a fraction of a second. (Engineers call this anti-islanding protection.) When the grid comes back, the inverter waits a short while to make sure power is stable, then starts up again on its own.
So a grid-tie system saves you money every day, but it isn't backup power.
What does a hybrid system do in a brownout?
A hybrid system has a battery and an inverter that can disconnect from the grid safely. When the power goes out, it cuts itself off from the grid lines and keeps your backup circuit running on battery and solar. The switch usually happens in a split second. Depending on the inverter, you might see the lights blink, or you might not notice at all.
- During the day: solar keeps running the backed-up appliances and tops up the battery.
- At night: everything on the backup circuit runs from the battery.
- When the grid returns: the system reconnects and goes back to normal on its own.
What if the battery runs out?
If a brownout runs through the night and the battery empties before sunrise, the backup circuit turns off. Once the sun is up, the panels start charging the battery again and the system comes back. Most hybrid inverters keep a small reserve in the battery so it never drains all the way to zero.
And off-grid systems?
An off-grid system isn't connected to the utility, so a brownout doesn't affect it. It runs on solar and batteries all the time. Many off-grid setups on islands keep a generator as a backup for long rainy spells.
I already have grid-tie. Can I add backup?
Usually, yes. If your inverter is battery-ready (hybrid), you can add a battery. If it's a standard grid-tie inverter, you'll need to add a hybrid inverter or swap it out. We can check what you have and tell you the simplest way. Contact us or request a free assessment.
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Get Free Solar QuoteCommon questions
Do solar panels work during a brownout?
The panels still produce power, but whether you can use it depends on your system. Grid-tie systems shut off for safety. Hybrid and off-grid systems with batteries keep running.
Why does my solar stop working when the power goes out?
If you have a grid-tie system, the inverter is designed to shut down during a brownout so it doesn't send power into lines that linemen may be repairing. It restarts on its own when the grid is back.
Will a hybrid system power my whole house during a brownout?
Usually only the circuits connected to the backup output. You choose which appliances go on backup, so the battery lasts as long as possible.
Can I add a battery to my existing grid-tie system?
Often, yes. With a battery-ready inverter you just add the battery. With a standard grid-tie inverter, you'll need a hybrid inverter as well.