howmuchsun

Off-grid solar and battery sizing, by city

How big a battery bank and how many panels you need to live off-grid — worked out from measured solar yield where you actually are, not a global average.

The mistake this exists to prevent

Almost every off-grid sizing guide works from the annual average of solar production. Systems built that way work beautifully all summer and run flat every winter, because in December a panel at 50° latitude makes a fraction of what it makes in June.

Size for the worst month. How much that costs you depends enormously on where you are: near the equator the difference between best month and worst is a few percent, and in northern Europe it is a factor of five or more.

1,232 cities across 236 countries, each with battery and array sizing for four household sizes, a month-by-month breakdown, and the seasonal swing you have to design around.

Browse by country