Size a complete off-grid solar system including array, battery and inverter.
Off-grid systems must be sized for the worst month rather than the annual average, which makes them substantially larger than grid-tied systems for the same load. The consequence is a large summer surplus that cannot be exported. That structural over-sizing is why off-grid systems cost far more per kWh delivered than grid-connected ones, and why load reduction pays back so strongly.
Off Grid Solar
Array = daily kWh ÷ (worst-month sun hours × derate); battery = daily kWh × autonomy ÷ DoD
Array = daily kWh ÷ (worst-month sun hours × derate); battery = daily kWh × autonomy ÷ DoD Off-grid systems must be sized for the worst month rather than the annual average, which makes them substantially larger than grid-tied systems for the same load. The consequence is a large summer surplus that cannot be exported.
That structural over-sizing is why off-grid systems cost far more per kWh delivered than grid-connected ones, and why load reduction pays back so strongly.
This calculator takes 6 inputs: Daily energy consumption, Worst-month peak sun hours, Days of autonomy, Depth of discharge, System losses, Peak load. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.