1. Your postcode
Sets the sun your roof gets, your electricity network and its tariffs, and the state rebates that apply. A 6.6 kW system makes about 24 kWh a day in Melbourne and 28 in Brisbane; the estimate uses your zone, not a national average.
Free estimate
Solar savings calculator: what could solar and a battery save your home?
Answer three questions and see an indicative estimate for your postcode — annual saving, the bill after solar, and the system size that fits. No contact details needed to see the number. Ask for installer quotes only if the estimate makes sense to you.
Calculate my savings · Free. No contact details to see your estimate.
How the calculator works
2. Do you already have solar panels?
No panels: the estimate models solar and a battery together. Panels already: it models adding a battery to what you have. Panels and a battery: it explores a battery scenario without assessing your existing unit.
3. Your electricity bill
Choose the band your bill sits in, after solar if you already have panels. The estimate works your daily usage back out of the bill, allowing for the fixed supply charge a battery never removes.
What the estimate is built on
- Electricity tariffs by network: the AER’s Default Market Offer 2026–27 caps for NSW, south-east Queensland and South Australia, and the Victorian Default Offer, degraded to a state average where a postcode cannot be resolved to a network.
- The federal Cheaper Home Batteries rebate at the rate in force on the day (6.8 certificates per usable kWh from 1 May 2026, 5.7 from 1 January 2027), and the solar STC rebate at the 2026 five-year deeming period.
- Solar output by Clean Energy Regulator postcode zone, and a self-consumption share that reflects a working household rather than a best case.
- A conservative feed-in tariff at the low end of your state’s range, so export income is never what carries the estimate.
What it is not
- It is not a quote. Purchase and installation costs are excluded from the saving, and a real price needs a roof, a switchboard and an installer.
- It does not know your roof, your shading, your phase supply or your export limit. Those move the answer and an installer checks them.
- It does not assess a battery you already own, and it does not model virtual power plant income.
Common questions
- How accurate is a solar savings calculator?
- It is an indicative estimate built on published tariffs, rebate rates and solar output for your postcode zone, with a conservative self-consumption share. Real savings depend on when you use power, your roof and the plan you are on. Treat it as the right order of magnitude, not a promise, and use installer quotes for the precise figure.
- How much can solar save on an electricity bill in Australia?
- A 6.6 kW system typically saves $1,100 to $1,800 a year according to Solar Calculator’s 2026 figures, and the spread is almost entirely how much of the output the household uses during the day. A battery lifts the share of solar you use yourself, which is where the additional saving comes from.
- Do I need to give my contact details to see the estimate?
- No. The estimate is shown after three answers: postcode, whether you already have solar panels, and your bill band. Contact details are only asked for if you then choose to request quotes from installers.
- What size solar system does the calculator recommend?
- It sizes from your usage, worked back from your bill. Most households land at 6.6 kW of panels and 10 to 13 kWh of battery; larger homes, all-electric homes and EV owners are pushed towards 10 kW and 20 kWh. Our system size and battery size guides explain the reasoning.
- Does the estimate include the solar and battery rebates?
- Yes. The federal solar rebate (STCs) and the federal battery rebate are applied at the rate in force on the day, and state programs that apply to your postcode are noted. Both federal rebates step down on 1 January 2027.
- What happens after I see my estimate?
- Nothing, unless you choose it. If the estimate is worth pursuing you can ask to be matched with 2-3 vetted solar installers — typically 2+ years in business, with a track record of decent reviews — who quote the system the estimate was built on. Free for homeowners, no obligation.