Sustainability
Instant, private, and free
Solar Panel Calculator.
Estimate solar array size from your energy use and your own sun-hour, panel-power, and loss assumptions.
Set your values
Results update as you type.
How to Use
Required array power = daily energy use ÷ (peak sun hours × (1 − system-loss fraction)).
Use locally measured or sourced assumptions for sun hours and losses; no location data or tariff is included.