Will solar panels work in a power outage?
Having solar doesn't mean you're covered in a blackout. Here's why your panels shut off automatically and what actually keeps the power on.
Key takeaways
- If you have a standard grid-connected solar system, you won't have power during a blackout, even if the sun's still out.
- Your inverter disconnects from the grid during an outage to stop your panels from sending power back into lines repair crews may be working on.
- This can be solved with a battery and hybrid inverter, which can disconnect from the grid and use stored power to keep your home running.
Solar panels won't keep your power on during an outage unless you have a home battery.
A standard grid-tied solar system automatically shuts off when the power goes out, even if the sun is shining. This is where it can get confusing, as it's easy to assume having solar means you're covered during an outage.
But that's not what a standard solar system is designed to do. Its main job is to help cut your power bills. If you want backup power during an outage, you'll need a home battery, along with the right inverter setup.
Why does solar stop working during a power outage?
The reason comes down to something called "backfeeding."
When the grid goes down, say a storm has knocked out a power line, crews need to know those lines are no longer live so they can work on them safely.
If your solar inverter kept sending electricity from your panels into the grid during an outage, it could re-energise a line that a technician believes is switched off.
That creates a serious risk of electrocution.
To prevent this, Australian safety standards require grid-tied inverters to have "anti-islanding protection".
It detects an outage and automatically disconnects your solar system within a fraction of a second.
Your panels can still generate electricity, but the inverter cuts the connection to your home and the grid.
Does a battery alone give you power during a blackout?
No, not on its own.
What matters is the type of inverter your battery is paired with. A standard grid-tied inverter will still shut down during an outage, even if you have a battery.
For blackout protection, you need a hybrid inverter or dedicated battery inverter that can detect the outage and switch your system into "island mode".
This disconnects your home from the grid and creates a separate circuit using your battery, and your solar panels too if it's daytime. This keeps the power flowing without sending electricity back into the grid.
The switch usually happens automatically within seconds, although some systems may have a brief interruption while they change over.
Did you know?
According to Finder's 2026 Energy Report, 39% of Aussies have solar, but only 16% of households have paired their panels with a battery.
What else do you need for solar battery backup to work?
Besides having a battery paired with a hybrid inverter, your system will also generally need:
- A battery that's actually backup-capable. Not every battery on the market supports blackout backup, some are built purely to store solar for later use, so check this before you buy.
- An essential loads circuit. This is separate wiring, set up at installation, that connects to the specific circuits you want kept alive during an outage.
- Correct installation. Backup protection has to be configured properly when the system goes in, it's not something you can bolt on or DIY later.
Miss one of these steps and you could end up with solar panels and a battery, but still no power when the grid goes down.
What actually stays on during a battery-backed outage
Not every battery system backs up your whole house, so it's worth what is and isn't covered. Broadly, there are two setups.
| Whole-home backup | Essential circuits only | |
|---|---|---|
| What stays on | Your entire home, including high-draw appliances like air conditioning, ovens and induction cooktops | A handful of chosen circuits: typically the fridge, some lighting, and your wifi/modem |
| Battery size needed | Larger, sized to your home's peak demand | Smaller: only needs to cover essential loads |
| Cost | Higher | Lower |
| Best for | Households that want full continuity during outages | Most Australian homes: the more common, more affordable setup |
Which one you get depends entirely on how your installer configures the system at installation time, not just which battery brand you choose.
If blackout protection matters to you, be specific with your installer about what you actually want to stay powered, rather than assuming a battery automatically means whole-home backup.
How long does solar battery backup last in a blackout?
It really comes down to two things: the size of your battery and how much power you're using.
If you're only running essential circuits (fridge, some lighting, wifi/modem), even a mid-sized battery can often last a day or more.
Whole-home backup, with air conditioning, ovens or other high-draw appliances running as normal, will drain a battery much faster, sometimes within hours.
Timing also matters.
If the outage happens during daylight hours, your panels keep generating power and can recharge your battery while you're using it, potentially extending your backup for as long as the sun's out.
Overnight, there's no solar input, so you're running purely on whatever charge is already stored until the sun comes back up.
How do you make solar battery backup last longer?
If you're in for an extended outage, a few habits can stretch your stored power further:
- Switch off non-essential appliances and devices at the wall, rather than leaving them on standby.
- Stagger high-draw appliances, like washing machines, kettles or air fryers, instead of running them at the same time.
- Check your system's app or built-in display, if it has one, to track how much charge you have left and adjust your usage accordingly.
- During daylight hours, prioritise essential tasks so your panels can top the battery back up before nightfall.
None of this replaces a properly sized battery, but it can be the difference between backup power lasting through a short outage versus running out halfway through.
Do you need blackout protection?
Whether it's worth paying extra for blackout protection depends on your circumstances more than anything else.
It can be worth prioritising if you live in a bushfire, storm or flood-prone area where extended outages are a real, recurring possibility.
It can also make sense if you work from home and rely on reliable power and internet during business hours. Or if someone in your household depends on medical equipment, refrigerated medication or other continuous power needs.
For a lot of other households, outages are rare and short enough that blackout protection is a nice-to-have rather than a necessity.
If your area only has one outage a year, lasting an hour or two, the extra cost of a bigger battery and backup wiring may not be worth it.
You might be better off putting that money towards a system that's designed to cut your bills.
There's no one-size-fits-all answer. It really comes down to whether the extra cost is worth the peace of mind for you.
Pros
- You live in a bushfire, storm or flood-prone area with frequent, extended outages
- You work from home and rely on power and internet during business hours
- Someone in your household depends on medical equipment or refrigerated medication
Cons
- Outages in your area are rare and short, maybe an hour or two, once a year
- You'd rather put the extra cost toward a system sized purely to cut your bills
Thinking about a battery for blackout protection?
If blackout protection has you thinking about adding a battery, it's worth understanding what you're signing up for.
Battery prices, payback periods and features vary a lot between brands and system sizes.
It's also worth understanding Virtual Power Plants (VPPs), which can let you earn extra income or rebates by allowing your battery to support the grid at peak times.
Some VPP arrangements can affect how much backup capacity is reserved for your own blackout protection, so it's worth checking before you sign up.
Compare solar batteries
See battery prices, capacities and blackout backup features side by side before you buy.
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