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Solar Panel Size Calculator
Estimate PV system size and panel count from daily energy and peak sun hours.
Formula
coverage_kwh_day = daily_energy_kwh * coverage system_efficiency = 1 - losses required_pv_kw = coverage_kwh_day / (peak_sun_hours * system_efficiency) panel_count = ceil(required_pv_w / panel_wattage_w)
Assumptions
- Inputs are user-provided.
- Results are preliminary estimates.
- Peak sun hours are provided by the user or trusted data.
Limitations
- Roof angle, azimuth, shading, snow, and interconnection rules are not modeled.
Methodology
Simple PV sizing based on daily energy divided by sun hours and efficiency.
This calculator provides an estimate for informational purposes only. It is not a certified engineering design, electrical safety approval, or professional installation recommendation. Always verify final decisions with a qualified professional and applicable local codes.