Serving 13 areas across Queensland | Call 1300 041 769
Serving 13 areas across Queensland | Call 1300 041 769
Home/Off-grid solar/Calculator
Estimate the solar array and battery bank an off-grid home needs, using local sunshine for your postcode.
Build a load profile from the appliances you actually use, set reserve days and your postcode sunshine, then calculate an indicative solar array and battery bank — with the maths shown. When you're ready, our team will design the real thing. Planning a full off-grid build? See our off-grid solar systems.
Pick the appliances you use, set how long they run, then dial in reserve days and local sunshine. You’ll get an indicative solar array and battery size — with the maths shown — before you talk to an installer.
Choose from common loads. Search or browse by category — selected items appear in the usage table below.
Edit quantity, running watts and hours per day. kWh/day updates as you type. Remove anything you don’t need.
| Item | Qty | Running W | Hours/day | kWh/day |
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Postcode drives local peak sun hours. Reserve days and simultaneous use shape the battery and inverter load.
Share of connected load that may run at once — used for peak / potential load.
Select appliances, set your postcode and tap Calculate.
Email delivery isn’t available on this staging calculator yet. Download the PDF, or request a quote and we’ll design the real system with you.
Indicative estimate only. This is a ballpark figure for planning, not a formal system design or quote. Real sizing depends on your load profile, surge loads, equipment, site shading, cable runs and local rules. A licensed electrician from Countryside Solar will assess your site before anything is installed. Phone 1300 041 769.
It gives an indicative, ballpark size for planning. It uses regional sunshine averages and standard allowances for losses, so it is a good starting point but not a system design. Your actual load profile, surge loads, equipment choice and site conditions all change the final numbers.
For a home that relies fully on off-grid power, we usually recommend winter sizing. Days are shorter and the sun is lower in June and July, so a system sized on the yearly average can fall short in winter and lean heavily on a generator.
Most off-grid homes with a backup generator are designed around about two days of storage. Without a generator, three or more days gives more breathing room through cloudy spells. More storage costs more, so it is a balance between budget and independence.
Modern lithium (LiFePO4) home batteries and off-grid inverters are mostly 48 V systems. A higher voltage means lower current, thinner cables and less energy lost as heat. 12 V and 24 V suit small cabins and caravans more than full homes.
Depth of discharge (DoD) is how much of the battery's rated capacity you can use. Lithium batteries typically allow 80 to 90%, while lead-acid batteries are usually limited to about 50% to protect their lifespan. A lower DoD means a larger battery bank for the same usable energy.
Most off-grid homes keep a backup generator for extended cloudy weather, unusually high use or maintenance. It lets you size the battery for one to two days rather than a week, which keeps costs sensible. Your installer can set it to start automatically when the battery runs low.
Yes. In Australia, north-facing panels produce the most energy, and a steeper pitch catches more of the low winter sun. East and west-facing panels still work well with a modest drop in output, while south-facing panels produce noticeably less.
Yes. Our SAA accredited installers design and install off-grid solar and battery systems for homes, farms and remote properties across our service areas, backed by our 25-year workmanship warranty. Request a quote and we will size the system around your property and how you use power.