How much does a solar battery cost?
The honest answer depends on your home. Here is the one government example we can source, what moves the price, and how to compare quotes.
A battery’s installed price depends on usable capacity, inverter, backup hardware and your switchboard. The most recent government example we found is about $13,000 for 11.5kWh, with around $4,000 off, published in May 2025 before the program changed. Your real price comes from a quote based on your bill and home.
Answered by Chris Bull, Managing Director Chris Bull on LinkedIn (opens in a new tab).
The price we can source
On 20 May 2025 the federal department used an example of an 11.5kWh battery costing around $13,000, with around $4,000 off under the program. That is a national illustration and it pre-dates the tiered rules that began on 1 May 2026.
We have not found a current government price range for South Australia. Rather than repeat figures we cannot source, we explain what drives the number. For an independent estimate, the government-backed SunSPOT calculator gives a guide to installed cost and savings using your bill.
What drives the price
Two batteries with the same headline size can sit far apart on price. These are the usual reasons.
- Usable capacity in kWh, which is what you can actually draw on
- Power output in kW, which sets how much it can run at once
- Whether you need a new or replacement inverter
- Backup hardware, if you want power during a blackout
- Switchboard upgrades and cable runs
- Single phase or three phase supply
- Where the battery can legally and practically be installed
How the discount changes it
The discount grows with usable capacity, but it tapers. The first 14kWh earns the full factor, the next 14kWh earns 60%, and capacity from 28kWh to 50kWh earns 15%.
So each extra kilowatt-hour buys less discount as the battery grows. At $40 an STC, a 14kWh usable battery has about $3,800 of STC value this year, and a 28kWh battery about $6,080. Those are our sums from the published rules, not quotes. The factor drops on 1 January 2027.
How big are batteries now?
The Clean Energy Regulator reports the average battery under the program was around 23kWh in May and June 2026, down from 36kWh in April, before the tiers began. Average does not mean right for you. Your evening use is the better starting point.
How to compare quotes
Put each quote on the same footing. The federal department says retailers must show the discount clearly against the system price.
- Usable capacity, not just the headline number
- The dollar value of the discount and when you receive it
- Any fees taken from the STC value
- What is included for backup and switchboard work
- Warranty length and who handles claims
- The anticipated payback period
Get a price for your home
We price a battery after looking at your bill, your solar and your switchboard. The 90-minute in-home consultation covers all three, and you see a detailed ROI based on your own numbers. Book a bill audit.
Common questions
How much is a solar battery for my home?
That depends on capacity, hardware and installation. We cannot give a fair figure without seeing your bill and switchboard, so we price it at your bill audit.
What is the cheapest solar battery available?
The lowest sticker price can be poor value if usable capacity or warranty is low. To get the federal discount, the battery must be on the Clean Energy Council approved list.
Is one 10kW battery better than two 5kW batteries?
Check the units first. kW is power and kWh is stored energy. Modular systems can suit some homes, and the discount only applies to one battery system per premises, so plan the whole size upfront.
How much does a battery cost per kWh?
We have no current government figure per kWh. Divide each quote’s price after discount by its usable capacity to compare them fairly.
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