Originally Posted by
fietsbob
Size matters in solar panels , or it will have little current output.
bring your mains plug in charger to lunch..
here's a 40watt that looks pretty good price/performance for touring, its about 4sq ft.
https://www.amazon.com/KINGSOLAR-Hig...+panel+folding
some of the 20watt ones look useful too for trickle charging.