Straight answers, 2026
Can I add a battery to my existing solar panels?
The short answer
Yes. Most homes with solar panels can add a battery, and the panels usually stay where they are. The part that usually changes is the inverter: most older systems have their existing inverter replaced with a hybrid inverter that runs both the panels and the battery.
Prices as at 21 August 2026. Incentives as at 14 August 2026. By Verified Solar. Last updated .
Why does the inverter usually change?
A standard solar inverter only converts power from the panels for the house. It cannot charge or run a battery. A hybrid inverter does both jobs, so most battery installations on an existing system replace the old inverter with a hybrid one and connect the panels to it.
Some homes keep their existing inverter and add a separate battery with its own inverter instead. Which way suits yours depends on the age and type of your current system, which an installer confirms on site.
What does it cost?
Installed battery prices after the federal discount, including the hybrid inverter in a typical job:
| Battery size | Typical installed price |
|---|---|
| 8 to 13 kWh | $8,550 to $10,925 |
| 14 to 22 kWh | $10,700 to $13,650 |
| 23 to 31 kWh | $13,650 to $17,450 |
| 32 to 40 kWh | $16,650 to $21,250 |
| 41 to 49 kWh | $19,600 to $25,050 |
Should I add more panels at the same time?
If your system is small, possibly. A battery stores what your panels make spare, and on some plans low cost or no charge grid power too. Panels added at the same time as a battery cost about $400 to $750 per kW, well below the $800 to $1,100 per kW for solar on its own, because the battery's hybrid inverter runs them too.
Can I still get the federal discount?
Yes. The Cheaper Home Batteries discount applies to a battery added to an existing system, and the installer takes it off your quote. It can only be claimed once per property, so it is worth sizing the battery properly the first time rather than adding a small one now and more later.
What should I check first?
- The size and age of your current system, from your installer paperwork or the inverter label.
- Your current feed-in tariff. If you are on an older or premium tariff, ask your retailer whether changing the system affects it before you go ahead.
- Whether you have single-phase or three-phase power.
- Space near the switchboard for the battery, and whether the switchboard needs an upgrade.
- That the quote names the exact battery, inverter and any new panel models in writing.
How do I find out for my home?
Tell Ray your bill and the size of your current system. He sizes the battery from your actual usage and explains which rebates apply before anyone quotes you. Where a verified installer covers your postcode, he can then introduce one verified local installer to check your existing system on site.
Common questions
Do I need new solar panels to add a battery?
No. Your existing panels usually stay. If the system is small, adding panels at the same time can make sense, at about $400 to $750 per kW alongside a battery.
Do I need a new inverter to add a battery?
Usually. Most existing systems have the old inverter replaced with a hybrid inverter that runs the panels and the battery. Some homes add a battery with its own separate inverter instead.
Can I get the battery discount if I already have solar?
Yes. The federal Cheaper Home Batteries discount applies to batteries added to existing systems. It can only be claimed once per property.
Get the answer for your home
Tell Ray your bill and what you are after. He sizes the system and explains the rebates before anyone quotes you. Free, and no details needed to start.