Enter your system size and latitude band to see the production swing between your best and worst months.
Higher latitudes see a bigger swing between summer and winter due to day length changes, not just sun angle — this matters for sizing battery backup that must work in winter.
Both day length and sun angle change with the seasons, and the effect grows stronger the further you are from the equator — a system in Minnesota sees a much bigger summer-to-winter swing than one in Florida. This matters when sizing a battery for winter reliability, since a battery bank sized around annual average production can fall short in the very months you need backup most. Check your annual production estimate alongside this seasonal breakdown for full-year planning.
Most grid-tied systems are sized around annual totals since summer surplus offsets winter shortfall through net metering — off-grid systems, however, generally need to size around the worst winter month.
Yes, temporarily — snow-covered panels produce near zero until they clear, though panels are typically dark and angled enough to shed snow within a day or two of sun exposure.