Solar System Size Calculator
Not sure what size solar system you need? This calculator estimates the kilowatts to suit your power bill, then prices the install, so you’re not guessing.
We estimate system size from typical household consumption per bill bracket.
- Panels$2,700
- Inverter$1,200
- Mounting & electrical$1,350
- Installation labour$1,500
💰 Ways to save
- Size to your actual usage, oversizing wastes money, undersizing leaves savings on the table.
- Make sure the federal STC rebate is shown as an upfront discount in the quote.
or from $33/week over 5 years , indicative finance
Run a trades business? Put a calculator like this on your own website, branded as yours.See how →How we estimate this
Solar in Australia in 2026 typically costs $900–$1,300 per kW installed after the federal rebate, so a 6.6kW system runs roughly $5,000–$8,000 and a 10kW system $9,000–$13,000.
Pricing reviewed: June 2026.
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Understanding solar system sizes in Australia
Solar in Australia in 2026 typically costs $900–$1,300 per kW installed after the federal rebate, so a 6.6kW system runs roughly $5,000–$8,000 and a 10kW system $9,000–$13,000.
The right size depends on your consumption, oversizing wastes money, undersizing leaves savings on the table. Adding a battery roughly doubles the project cost but increases self-sufficiency.
Frequently asked questions
What size solar system do I need?
It depends on your consumption. As a guide, a ~$500 quarterly bill suits a 6.6kW system; a $1,000+ bill may need 13kW. The calculator estimates this from your bill.
How much does solar cost in Australia?
About $900–$1,300 per kW installed after rebate in 2026, roughly $5,000–$8,000 for 6.6kW and $9,000–$13,000 for 10kW.
Is a solar battery worth it?
Batteries increase self-sufficiency and backup but roughly double the project cost. Payback depends on your usage pattern and any battery rebates.
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