Calculate recommended solar panels and battery bank for your Australian off-grid system.
Australia has some of the best solar resources in the world, and feed-in tariffs aside, the economics of solar have improved dramatically over the past decade. But whether it's worth it for your specific house depends on your roof orientation, how much power you use, and when you use it.
This calculator estimates how much a solar system of a given size would generate at your location, how much of that you'd use directly, and what the saving looks like on your power bill. It's a rough guide — actual output depends on your specific roof pitch, shading, panel efficiency, and local weather patterns.
Self-consumption is the key variable. If you use most of your power at night when solar isn't generating, a battery may be worth considering alongside the panels. If you're home during the day, self-consumption can be very high and the economics are more straightforward.
The most common residential system in Australia is 6.6kW, which suits a household using 20-30kWh per day. Smaller households (under 15kWh/day) may do well with a 3-5kW system. Larger households or those with EVs or pools often go 10kW or more. Your retailer will size the system based on your bills.
Feed-in tariffs — what you're paid for excess power exported to the grid — have fallen significantly and now typically range from 5-12c/kWh depending on state and retailer. This is much less than the cost of buying power, which is why self-consumption (using the power you generate rather than exporting it) is so important.
Battery economics are improving but payback periods are still long — typically 8-12 years for a residential battery, versus 4-7 years for panels alone. Batteries make most sense if you have high evening usage, live in an area with frequent outages, or have a time-of-use tariff with expensive peak rates.
Look for Clean Energy Council (CEC) accredited installers, check Google and Product Review ratings, and get at least three quotes. Avoid door-to-door solar sales and any quote that seems dramatically cheaper than others — quality of installation matters as much as the panels themselves.