Why solar turns off when the grid goes down
Grid-connected inverters must meet the Australian standard for grid connection, which requires them to disconnect when the grid fails. This is called anti-islanding protection. Without it, a home system could energise a line that the network has turned off for repairs.
So unless your system was designed for backup, the inverter shuts down within seconds of a blackout and restarts automatically after the grid has been back for a short time.
How to get backup power from solar
Battery with backup
Most common- Keeps chosen circuits or the whole home running
- Solar recharges the battery during a long outage
- Needs backup-capable hardware, not every battery has it
- Extra wiring and a changeover device add cost
Inverter emergency outlet
Some models- Low cost
- Powers a fridge or phone chargers in daylight
- Daytime only, and output changes with cloud
- Separate power point, not your house circuits
Backup is a design choice, not an automatic feature of a battery. Some batteries only back up selected circuits, some back up the whole house, and some have no backup at all. Ask the installer exactly what will run in a blackout, and for how long. See AC and DC coupled batteries and Tesla Powerwall, which uses a backup gateway.
Choose your backup circuits carefully
Fridge, lights, internet, a few power points and any medical equipment are the usual picks. Air conditioners, ovens and electric hot water use a lot and can drain a battery quickly.
Life support and medical equipment
If someone in your home relies on life support equipment, register with your retailer and network so you get notice of planned outages. A battery can help but is not a substitute for a backup plan. See medical equipment and electricity and our blackout checklist.
Common questions
Not on a standard grid-connected system. The inverter must shut down in a blackout so it cannot send power into lines being repaired.
No. Backup needs compatible hardware and wiring. Some batteries back up selected circuits, some the whole home, and some none. Check before you buy.
It depends on battery size and what is running. A fridge, lights and internet draw little; air conditioning and cooking draw a lot. Solar can recharge a backup battery during the day.
Sources
Rules and program details come from government sources. Prices are industry averages, named and dated where used. Last checked October 2026. Prices include GST unless we say otherwise.