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Solar System Cost Calculator: How It Works

What a good solar calculator measures, and how to read the results so you don't get oversold.

Inputs that drive accuracy

Monthly electricity bill, average monthly kWh consumption, country/state, roof type and shading. The calculator uses local irradiance and tariff data to estimate system size and payback.

Outputs you should expect

Recommended system size in kW, panel count, gross and net cost (after subsidy/ITC), monthly and 25-year savings, simple payback period and CO2 offset.

Frequently asked

How accurate are solar calculators?
Within ±10–15% if you input an accurate monthly bill. A site survey is needed for a binding quote.

Ready to take the next step?

Free, no-obligation. Takes under 2 minutes.

Open the calculator

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