Independent buying guides for RV upgrades and maintenance

RV Battery and Solar Calculator

Enter how much 12V energy you use per day. We size the battery bank and the solar array needed to refill it.

Result

Battery bank
200 Ah
Solar array
350 W
Daily energy
1,024 Wh

Real solar output is usually 70-80% of panel rating after heat, angle and wiring losses, which this estimate includes.

How this calculator works

Battery capacity = daily Ah x days / usable fraction. Solar watts = daily Ah x 12.8 V / (peak sun hours x 0.75 system efficiency), so the array refills one day's use on a typical sunny day.