Solar System Size Calculator

Find the right solar system size for your home. Enter your monthly electricity usage and location to get recommended system size in kW and number of panels needed.

Monthly Usage (kWh)

Your Region

Panel Wattage (W)

System Loss % (default 14)

System Size

7.75 kW

Panels Needed

20 panels

Roof Area Needed

350 sq ft

Annual Production

10,950 kWh

Based on 4.5 peak sun hours/day in the Midwest. Each 400W panel needs ~17.5 sq ft of roof space. 14% system losses accounted for (wiring, inverter, shading).

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