Tablet solar charging

Does anyone have experience charging a tablet with a solar panel in a window?  I am mounting a Fire 7 next to my kitchen door and due to the construction of the exterior walls, there is no good way to install an outlet.  My thought is getting a solar panel to hang in the window and try to charge like that.  I know the power output is decreased when behind glass but I don't know what would be a good quality panel to use.