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Solar sizer

How much solar might I need?

Estimate a system size, yearly generation, indicative savings and payback from your bill and how you use power. A guide to start the conversation — not a quote.

Use your most recent bill. Business? Use one quarter's total.
Leave 0 if you're not sure. Roughly 5 m² per kW installed.
30%
Empty house until 6pm? Around 20%. Business running all day? 60%+.
RECOMMENDED SIZE
ESTIMATED GENERATION
INDICATIVE BILL SAVING
STC DISCOUNT
NET COST AFTER DISCOUNT
INDICATIVE PAYBACK

That's roughly panels at 440 W each. Figures are indicative and depend on your roof orientation, shading, tariff and how much you use during the day.

Your calculator result is sent with the enquiry so we can check it properly.

Assumptions used
  • Imported electricity at $0.35/kWh; feed-in credit at $0.05/kWh
  • Sydney yield of 1,400 kWh per kW per year, good orientation, minimal shading
  • Roof area of 5 m² per kW installed
  • STC zone rating 1.382 (NSW Zone 3), 5 deeming years remaining (2026–2030), $38 per certificate
  • Installed cost $1,050/kW under 10 kW, $900/kW above
  • Business self-consumption assumed 25 percentage points higher than the slider value
A guide, not a quote

These calculators work from published industry assumptions. They cannot see your roof, your shading, your tariff or your meter, so treat every number as a rough starting point rather than an answer. Talk to us and we'll go through it properly and put the real figures in writing.

Next step

Ready to find out what your place could do?

Every quote starts with a proper look at your bills, your roof and how you actually use power. No obligation, no cost.