Right-sized home batteries gain ground: what it costs
Mid-sized home batteries are now Australia's biggest segment, according to Ecogeneration. Here is what that means for solar and battery costs.
Households are buying smaller home batteries than they were a year ago, and that is good news for the budget. A battery in the 10 kWh to 13.5 kWh range costs a fraction of a very large system. On our live model, solar with a 10 kWh battery sits at $10,400 and with a 13.5 kWh battery at $11,400, both mid-range and including GST.
What happened
According to Ecogeneration, SunWiz data for July 2026 shows the 20 to 30 kWh battery band grew 18 per cent month-on-month. That made it Australia's largest storage segment, ahead of the 40 to 50 kWh band.
The article is a manufacturer-supplied piece from inverter and battery maker Growatt. Its operations and marketing vice president describes the change as a move from "bigger is better" to right-sizing. In that account, households are matching battery capacity to what they use and to the subsidy on offer.
Ecogeneration also reports on two policy points:
- Solar Sharer Offer: Introduced in July 2026, it gives eligible households in New South Wales, South Australia and South East Queensland three hours of free electricity in the middle of the day.
- Cheaper Home Batteries Program: Eligible on-grid batteries installed under the program must be technically capable of joining a virtual power plant (VPP). Households don't have to join one.
The same piece describes modular, expandable battery systems that let a household start small and add capacity later.
What it means for your costs
We can't price a 20 to 30 kWh system from this story. Our solar battery options top out at 13.5 kWh, so treat the figures below as a guide to the smaller end of the market. For a bigger system, get itemised quotes.
Here is how the options compare on our model, for a typical solar system with a battery:
| Material | Typical | Usual range | Lifespan |
|---|---|---|---|
| No battery | $7,500 | $5,850 – $9,750 | – |
| 5 kWh battery | $8,900 | $6,950 – $11,600 | – |
| 10 kWh battery | $10,400 | $8,100 – $13,500 | – |
| 13.5 kWh battery | $11,400 | $8,850 – $14,800 | – |
For reference, the solar system on its own, with no battery, is covered in our [solar panel cost guide](Solar panels). Typical solar prices are $6,950 – $11,600 at mid-range, and basic and premium systems come in at $7,500 and $10,600.
Why right-sizing can save money
A bigger battery only pays off if you use the extra storage. Cost rises with capacity, and a battery that never fully cycles is money tied up. Before you choose a size, look at:
- Your evening usage. Your bills show when you draw power from the grid. A battery needs to cover that period, not your whole day.
- Your tariff. If you are on time-of-use rates, storing cheap or free daytime power helps. The Solar Sharer Offer may also change what is worth storing in the three eligible regions.
- Future loads. An electric vehicle, an electric hot water system or more air conditioning will raise your demand later. Modular systems that expand are one way to allow for this without paying for it now.
Related projects that change your battery sizing
If you plan to add a big new load, price it alongside the battery:
- EV charger: A typical install is $2,500, with a range of $1,950 – $3,250. See our [EV charger cost guide](EV charger).
- Heat pump hot water: A typical mid-range install is $4,500. Prices are usually quoted after STCs, the federal discount that steps down each year until 2030. See our [heat pump hot water guide](Heat pump hot water).
- Split system air conditioning: A typical three-room install is $9,000. See our [air conditioning guide](Split system air conditioning).
Shifting hot water heating into the middle of the day suits a solar-plus-battery home. You can then size the battery for the evening load and not for everything.
Check the subsidy and the paperwork
Under the federal Cheaper Home Batteries Program, the discount is delivered through certificates and reduces every six months until 2030. Waiting can therefore cost you more in discount than it saves in hardware. Two state schemes also exist:
- Victoria: The Solar Homes panel rebate is up to $1,400, with a household income cap of $150,000 from 1 July 2026.
- Western Australia: The residential battery scheme pays up to $1,300 (Synergy) or $3,800 (Horizon Power), with virtual power plant participation.
Electrical work must be done by a licensed tradesperson. In Victoria, a licensed electrician lodges the Certificate of Electrical Safety with Energy Safe Victoria. Ask whether the quote includes the discount, any switchboard work and the certificate.
How we calculate
Our figures combine labour hours at local rates with equipment and materials. We check them against market prices and real quotes. All amounts include 10% GST. They are typical costs, not a quote for your home.
If you already have a battery quote in hand, run it through our quote checker ("is my quote fair") before you sign. Compare the capacity, the inverter, the backup circuits and whether the discount has been taken off the price.