BrightGridMany homeowners assume that solar panels and a battery will automatically keep the house powered during a power cut. In most standard grid-connected installations, that is not the case. Backup requires equipment and wiring specifically designed to operate safely when the grid is unavailable.
Why does ordinary solar stop during a power cut?
Grid-connected solar systems are normally designed to disconnect from the electricity network when the grid supply fails. This helps protect network workers and equipment.
What does a backup system require?
- A compatible battery
- An inverter capable of backup operation
- Suitable electrical isolation
- Appropriate backup distribution
- Correct control and protection equipment
- Professional commissioning
Whole-house versus essential-load backup
Some systems can support selected circuits rather than the entire property. Essential-load backup may focus on lighting, refrigeration, internet equipment and selected sockets rather than high-demand appliances.
| Backup approach | Typical purpose |
|---|---|
| Essential loads | Keep selected important circuits operating |
| Whole-home backup | Potentially supply a wider range of household circuits |
| Solar + battery backup | Battery provides stored energy and solar may recharge it when conditions permit |
How long can a battery provide backup?
Backup duration depends on usable battery capacity and the electrical load being supplied. A small load can operate for much longer than a large load from the same battery.
Backup should be specified before installation
If backup power is important, tell your installer before the system is designed. Adding backup functionality later may require changes to the inverter and electrical architecture.
Plan battery backup for your home
Explore battery systems with backup capability and determine which household circuits you may want to protect.
Explore Battery SystemsFrequently asked questions
Will solar panels work during a power cut?
A normal grid-connected system generally disconnects during a grid outage. Backup functionality requires suitable equipment and electrical isolation.
Can a solar battery power my house during an outage?
A compatible battery and inverter system can provide backup power when designed and installed for that purpose.
Can a battery power the whole house?
Some systems can support whole-home backup, while others are designed for selected essential circuits.
Can solar recharge the battery during a power cut?
Some backup-capable systems can use solar generation during an outage, depending on their architecture and configuration.
Marcus Webb
Head of Engineering at BrightGrid Energy
