Still hesitant if flying a GPS triangle is right for you and just want to try it out

What do I use to power the drive battery charger?

We have completed the first wing with a solar panel. We did exactly what we wanted. You've considered all the options, tried all the alternatives. Solar roofs and "arrays" hardly surprise anyone today, so why not try "solarizing" the wing and conveniently charging in flight. This was the initial idea that came to mind at the end of 2019.