(from spiegel.de source Sören Harder:)
An American couple has found a surprising alternative to conventional asphalt motorways: solar road panels. In addition to providing electricity, saving oil and melting fresh snow, it could also prevent accidents. … are heated and equipped with integrated LED screens, which act not only as street markings, but can also show warnings directly on the road … glass is what it is, so glass is what we must call it … Along the sides of the modules are canals that collect water drainage for filtering. That way the water isn’t wasted and can be used to water fields, for example. … if one solar road panel is broken, it can simply be replaced, because all of the elements connect to create an intelligent street network, which can even use LED lights to alert drivers to dangers around the next curve … solar roads have massive potential … cost about three times as much as conventional roads
Brilliant, not for everywhere but usable, another couple of things that can add to efficiency are half track cars (being now actually produced,) which require more narrow lines, and the possible relief on the weight of battery needed, moving “fuel” out of individual vehicles reduces weight.