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Solar & Battery Sizing Calculator
If you are comparing quotes, this page helps you see how solar and a battery could affect your bills and self-sufficiency
before you speak to installers — start in the
buying guide for more context.
Use this free solar and battery sizing calculator to estimate the right system size for your home,
see typical costs and savings, and explore how adding a home battery affects self-sufficiency and payback.
Adjust energy usage, system size, and battery capacity by country to get a tailored estimate.
For more accurate results and full design outcomes, use the Photonik app.
Solar Design
Energy Usage
Typical energy usage per person per day:
Low (Efficient)
~5 kWh
Medium (average)
~10 kWh
High (intensive)
~15+ kWh
Note: Actual usage varies depending on property size, building efficiency, climate, and appliances.
5 kWh100 kWh
$/kWh
$/kWh
$/kWh
%
lightbulbNote: These are simplified estimates. For detailed tariff inputs and advanced calculations, use the full Photonik app.
Representative flat export rate (feed-in tariff). What you earn per kWh of surplus solar exported to the grid. Your actual rate depends on your provider, plan, and time of day.
Estimated at 75% of the retail grid rate. A battery lets you store daytime solar and export during expensive peak hours, so each exported kWh is typically worth more than a flat feed-in tariff. Real returns depend on your time-of-use tariff and battery efficiency.
A 8 kW system in Australia can generate approximately 12446.0 kWh annually based on local sun conditions.
Solar & Energy Savings
Calculating...
Old Bill (Before Solar):Monthly:-|Annual:-
New Bill (With Solar):Monthly:-|Annual:-
Monthly Savings
$0
Annual savings: $0 | Bill Savings: 0%
Battery Storage
Solar Battery Sizing
0 kWh30 kWh
lightbulb
A 0kWh battery will make you about 0% self sufficient.
The sweet spot for most households is 5 – 13 kWh — larger batteries add independence but with diminishing payback, especially where feed-in tariffs are low.
Calculating...
Estimated Solar & Battery Price
0
%
Adjust tax rate if needed
Energy Self Sufficiency Calculator*
Calculating...
Lowest Month
-
-
Annual Average
-
Year-Round Estimate
Highest Month
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-
Lowest Month Details
Annual Average Details
Highest Month Details
Note: Self-sufficiency varies significantly by season. The annual estimate is a simple average of best and worst months.
*Note: This calculator provides simplified battery self-sufficiency estimates. For accurate per-hour
simulations, use the full Photonik design tool.
Ready to see your savings in detail?
Photonik helps you model solar and batteries for your home, then connect with installers when you are ready.
