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Solar System Size Calculator

Size a solar array from your usage and sun hours.

Inputs

Inputs and assumptions

Monthly usage

120% oversizes for future EV or electrification.

Peak sun hours

Soiling, wiring, inverter, and shading losses.

Panel wattage

Result

Panels needed
Waiting for calculation.
Roof area needed
Waiting for calculation.
Suggested system size
Waiting for calculation.
This calculator is a first-pass screening tool. Verify your utility tariff, metered usage, equipment specifications, and installer quotes before making a decision.

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Workspace

Keep the assumptions with the result.

Save this calculation to return to the inputs, result, and report from your private workspace.

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