6.6kW vs 10kW Solar System
Sydney is experiencing a major boom in solar installations — and for good reason. Electricity prices continue to rise across NSW, while rooftop solar has become more affordable than ever. Government rebates significantly reduce upfront costs. With Sydney’s strong sunshine levels, homeowners can dramatically cut their energy bills while increasing the value of their property.
Among all system sizes, 6.6kW and 10kW solar systems are the two most popular choices for Sydney households. Both offer excellent savings, but each suits different energy needs, roof sizes, and budgets.
So the big question is: Which solar system is right for your home — 6.6kW or 10kW?
System Overview
6.6kW Solar System
- Panels required: 14–15 panels (based on 440–475W panels)
- Average daily output in Sydney: ~26–30 kWh
- Best suited for: Medium-sized households (3–4 people), average electricity usage
10kW Solar System
- Panels required: 21–23 panels
- Average daily output in Sydney: ~35–40 kWh
- Best suited for:
- Large homes, homes with high consumption, or small businesses
Comparison Table: 6.6kW vs 10kW Solar System
Feature | 6.6kW System | 10kW System |
Panels Required | 13–15 | 21-23 |
Daily Output (Sydney) | 26–30 kWh | 40-45 kWh |
Best Fot | Medium households | Large homes / small businesses |
Roof Space Needed | 30–35 m² | 50–60 m² |
Average Savings/Year | $1,500–$2,000 | $2,500–$3,500 |
Payback Period | 3–4 years | 4–5 years |
Savings & Payback
Average Annual Savings
- 6.6kW system: ~$1,500–$2,000 per year
- 10kW system: ~$2,500–$3,500 per year
Payback Depends On:
- Your daily electricity usage
- Feed-in tariff rates (typically 5–15c/kWh in NSW)
- Whether you use most power during the day
- Whether you add a battery
Both system sizes significantly reduce electricity bills, with 10kW offering higher potential savings — especially for families with high consumption.
Battery Compatibility
Both systems work well with battery storage, but battery sizes differ:
6.6kW Solar System + Battery
- Recommended battery size: 5–10kWh
- Ideal for medium households wanting evening backup and bill reduction
- Helps reach up to 70–80% energy self-sufficiency
10kW Solar System + Battery
- Recommended battery size: 10–15kWh
- More suitable for high-usage homes, EV charging, or pool equipment
- Provides strong blackout protection and maximizes solar self-consumption
In Sydney, batteries also help make the most of solar during cloudy days and reduce reliance on the grid.
Which System is Better for Sydney Homes?
Choose a 6.6kW system if:
- You have medium electricity usage
- You want an affordable system
- Your roof space is limited
- You want a quick payback period
Choose a 10kW system if:
- You have high electricity usage (large family, electric hot water, EV, pool)
- You have plenty of roof space
- You have plenty of roof space
- You want to future-proof your home
- You plan to add a large battery
Both systems are excellent, but your household energy needs will determine the best option
FAQs
Yes, many Sydney homes with single-phase power can install a 10kW system, but export limits (usually 5kW) may apply depending on your DNSP.
A 6.6kW system suits most medium households with average daily consumption.
Homeowners can claim the federal STC rebate, reducing the cost by $1,000–$2,500 depending on system size.
Most installations take 1 day, while larger or complex jobs may take 2 days.
Conclusion:
Both 6.6kW and 10kW solar systems are excellent options for Sydney homes. The right choice depends on your electricity usage, roof space, and future energy plans.
If you want maximum savings and long-term energy security, choosing the right system size is the first step.
Get a free quote for your Sydney home today and find the perfect solar system for your needs.
