Solar Array Size & Panel Count

Size a solar PV system from your daily energy use, peak sun hours and losses, free online.

Daily energy use (kWh)

Peak sun hours per day

System efficiency / performance ratio (%)

Panel rating (watts)

Area per panel (m²)

Acerca de esta calculadora

Array size (kW) = daily energy use (kWh) ÷ (peak sun hours × system efficiency). System efficiency (performance ratio) is typically 75–85% after inverter, wiring, temperature and dirt losses. Divide by the panel wattage for the panel count.