so IMHO...the best possible scenarios in the near future...for a self contained recharging system while riding a ebike , would involve a solar cube rated at 200 watts or more with slightly higher voltage then the battery pack...and then have that tied in with a regenerative braking or brushless hub system that generates power when braking and going down hills, etc....of course with this type of system, you are at the mercy of the sun . on cloudy or rainy days , or at night..the solar part of the system would be near useless