Van Solar in Arizona
Arizona has the strongest, most consistent sun in the country, so arrays are smaller here than almost anywhere. The real design driver in the desert is heat: high temperatures reduce panel output and stress batteries, so keep airflow under panels and avoid parking batteries in direct sun. Summer air conditioning, not lighting, is what pushes Arizona loads up.
How to plan a build for Arizona
Arizona is the one region where the array is rarely the problem, because 4.8 winter peak sun hours is better than many places manage in summer. Design for heat instead. Panel output falls as cell temperature rises, so leave an air gap under rigid panels rather than mounting flush, and keep the battery out of direct sun and away from an uninsulated floor. The load that catches people out is cooling: a roof fan running 12 hours plus a 12V air conditioner in July will double a build's daily watt-hours, and that is a battery and inverter problem, not a panel problem. Size the array on the annual figure, then size the battery on your worst summer day.
Take a steady 1,500 Wh/day build. At Arizona's annual 6.5 peak sun hours that needs about 308 W of solar. In winter, with only 4.8 hours, the same load needs about 417 W — that is the ×1.4 winter penalty in one number. Size your array for the season you actually travel, and let the battery cover the cloudy days.
The calculator below is prefilled with Arizona sun. Add your loads and toggle winter to see your own numbers.
Quick start with a profile:
Your daily loads
Add each device with its watts and hours per day.
No loads yet. Add your fridge to start, or pick a profile above.
Solar array
—
Add loads to size your array.
Show the math
Battery bank
—
Show the math
Charge controller (MPPT)
—
Show the math
Inverter
—
Show the math
Battery-to-inverter wire & fuse
—
Show the math
Estimated cost
—
Budget street price → premium brands.
Itemized breakdown
Embed
Free to use on your own site — just keep the credit link. Sizing and options.