Off-grid and RV solar guides
Every number on these pages comes from measured solar data for a real location, with the method written out so you can check it.
What Size Off-Grid Solar System Do I Need? A Sizing Guide Built on Real Sun Data
The same 1 kW array makes 4.0 kWh a day in a Phoenix December and 1.1 kWh in Seattle. Size for your worst month, not a national average.
October 21, 2026 · 7 min read
How Much Solar Do I Need for My RV? Winter and Summer Numbers by Location
RV panels lie flat, so winter hits them harder than home systems. Here is the array size a 1,200 Wh boondocking day needs, by location and month.
October 21, 2026 · 5 min read
How Many Batteries Do I Need for Off-Grid Solar? Battery Bank Sizing With Real Winter Data
Battery count comes from three numbers: daily watt-hours, days of autonomy and usable depth of discharge. Here is the math, plus why a bigger bank cannot fix a winter shortfall.
October 21, 2026 · 5 min read
Solar Panels in Winter: How Much Output Drops by Location in the US, UK and Europe
Solar panels keep working in winter, but how much they make depends heavily on latitude and clouds. December output ranges from about 8% of June in Stockholm to 98% in Miami.
October 21, 2026 · 5 min read