Solar System Size Comparison (AUD)
| Size | Panels | Price Range | Annual Output | Annual Savings | Payback | Best For |
|---|---|---|---|---|---|---|
| 3kW | 8-10 | A$3,500 - A$5,500 | 2,550 kWh | A$500-A$750 | 10-13 years | 1-2 bedroom flat or house |
| 4kW | 10-12 | A$4,500 - A$7,000 | 3,400 kWh | A$650-A$1,000 | 9-12 years | 2-3 bedroom house |
| 5kW | 12-14 | A$5,500 - A$8,500 | 4,250 kWh | A$800-A$1,250 | 8-11 years | 3-4 bedroom house |
| 6kW | 14-16 | A$6,500 - A$10,000 | 5,100 kWh | A$1,000-A$1,500 | 8-11 years | 4+ bedroom house |
| 8kW | 18-22 | A$8,000 - A$13,000 | 6,800 kWh | A$1,300-A$2,000 | 7-10 years | Large property or small commercial |
| 10kW | 24-28 | A$10,000 - A$16,000 | 8,500 kWh | A$1,600-A$2,500 | 7-10 years | Very large home or commercial property |
* Prices include installation in Australia. Actual costs vary by location, roof type, and installer. Get CEC-certified quotes for an accurate price.
How to Choose the Right Solar System Size
Choosing the right solar system size depends on your electricity consumption, roof space, budget, and future plans. Here's a practical guide to help you decide:
1. Check Your Electricity Usage
Look at your energy bills to find your annual electricity consumption in kWh. As a general rule, your solar system should generate at least as much as you use:
- Under 3,000 kWh/year: 3kW system
- 3,000-4,000 kWh/year: 4kW system
- 4,000-5,000 kWh/year: 5kW system
- 5,000-6,500 kWh/year: 6kW system
- 6,500-8,500 kWh/year: 8kW system
- 8,500+ kWh/year: 10kW system
2. Assess Your Roof Space
Each solar panel requires about 1.7-2 m² of roof space. A north-facing roof with minimal shading is ideal. Your installer will conduct a survey to determine exactly how many panels your roof can accommodate.
3. Consider Future Needs
If you plan to add an electric vehicle, heat pump, or home battery in the next few years, it's often more cost-effective to install a slightly larger system now. The marginal cost of additional panels during initial installation is lower than adding them later.
4. Budget and Payback
Larger systems cost more upfront but offer a lower cost per kWh generated and faster payback periods. All systems listed above are eligible for Solar Rebates (STCs) in Australia, which improves the financial returns.
Explore Each System Size
3kW
A$3,500 - A$5,500
8-10 panels
2,550 kWh/year
Save A$500-A$750/year
1-2 bedroom flat or house
4kW
A$4,500 - A$7,000
10-12 panels
3,400 kWh/year
Save A$650-A$1,000/year
2-3 bedroom house
5kW
A$5,500 - A$8,500
12-14 panels
4,250 kWh/year
Save A$800-A$1,250/year
3-4 bedroom house
6kW
A$6,500 - A$10,000
14-16 panels
5,100 kWh/year
Save A$1,000-A$1,500/year
4+ bedroom house
8kW
A$8,000 - A$13,000
18-22 panels
6,800 kWh/year
Save A$1,300-A$2,000/year
Large property or small commercial
10kW
A$10,000 - A$16,000
24-28 panels
8,500 kWh/year
Save A$1,600-A$2,500/year
Very large home or commercial property
Not Sure Which Size You Need?
Get free, no-obligation quotes from CEC-certified installers in Australia. They'll assess your roof and energy usage to recommend the perfect system size.
Get Your Free Quotes