RV solar planning
RV solar sizing checklist
An RV solar plan works better when every number comes from the same daily load list. Use this checklist before comparing panels, batteries, inverters, or charge controllers.
1. Record each daily load
- Use measured watts or documented energy where possible.
- Separate quantity and hours per day.
- Use a daily energy figure for cycling refrigerators.
- Keep AC and DC loads identifiable.
2. Decide how long the battery must last
Choose autonomy for the trip you are planning, not an arbitrary large number. Apply depth of discharge, battery efficiency, inverter loss for AC loads, and an explicit reserve.
3. Select a system voltage deliberately
Check the supported voltage of the inverter, charger, controller, alternator charging equipment, and DC appliances. Higher voltage lowers current for the same power but does not make incompatible equipment work together.
4. Size solar for the daily energy
Use peak sun hours for the place and season, not daylight duration. Round panel count upward and recalculate production from the installed array.
5. Check controller and roof constraints
The basic controller-current estimate does not check cold-weather Voc, Isc, controller voltage window, wiring, shading, roof vents, mounting, or structural loads. Verify those against current equipment documents.
6. Keep an energy margin you can explain
A margin should cover a named uncertainty such as cloudy days or battery aging. Avoid stacking several hidden safety factors that make the result impossible to audit.
Build the complete scenario in the RV solar calculator. Use the runtime calculator to check a battery you already own.