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    Solar production calculator

    Calculate production, then turn it into a roof plan.

    Start with the numbers already on your bill and panel quote: location, panel wattage, panel count, and monthly electricity use. Then carry the same inputs into a roof-based project when the estimate looks worth pricing.

    Panel output

    Compare what one panel can produce by city.

    Usage match

    Estimate panel count from your monthly kWh.

    Full project

    Carry the estimate into roof, battery, and supplier decisions.

    Quick production estimate

    Choose a city to load a PVWatts-backed production estimate.

    Choose a city first

    Then this card will show per-panel output, array production, bill value, and the panel count needed for your usage.

    Size a full roof project
    Browse supported city calculators

    Choose a city for a detailed PVWatts production breakdown, or use the quick estimator above to carry panel count and monthly usage into a roof project.

    Africa

    17 locations

    Asia

    17 locations

    Australia

    5 locations

    Europe

    19 locations

    North America

    17 locations

    South America

    9 locations

    Solar data assumptions

    The quick estimator loads PVWatts® Calculator data from NLR for the selected city in the browser. The detailed city pages use the same provider for the full monthly production breakdown, assuming latitude angle as tilt, equator-facing panels, and 14% system losses.

    Solar panel production calculator for all locations | Size.Solar