Solar powered Bike Battery charger (and cover)

The same one as the one in the plastic tray at the bottom of the web link?

it is, didnt work at first then made sure it faced south and at e slightly different angle to the roof. not sure how well it would work in a cover

Hmmm, might get the panel out again a do some more testing for current. I remember it was 13V+ but can't remember the current draw from it :-/

for all year round you want panel at 40 deg angle and an air gap underneath to keep it cool.