Solar output
What will your panels make where you camp?
Enter a ZIP or a town. You get last year's sunlight month by month, the season numbers to plan around, and what the next seven days look like.
Sunlight data from Open-Meteo
Sun hours, last full year
Look up a place to see last year's sunlight there, month by month.
Next seven days
The forecast appears here after a lookup.
How the math works
Open-Meteo reports how much sunlight lands on flat ground each day, in megajoules per square meter. Divide by 3.6 and you get kilowatt-hours per square meter, which is the same number as peak sun hours. RV panels lie flat, so that's the right figure for a roof.
Daily output = sun hours × panel watts × 0.75, the same efficiency the Megawatt solar calculator uses. The season numbers average last calendar year's days: winter is December through February, summer is June through August, and spring and fall are the rest.
The state-of-charge line is bookkeeping. It adds what the panels make, subtracts what you use, and keeps the battery between empty and full. It isn't a shunt reading.
Data: Open-Meteo forecast and historical weather APIs (CC BY 4.0). ZIP lookups by Zippopotam.us.