Solar roadways is a bad engineering concept, but as a political source of funding it's brilliant!
No really, think about it for a moment: most people don't understand anything about science, engineering, math, economics, or logic, but they like shiny things. The sun is shiny, solar panels are shiny, and celebrities with bleached teeth talking about solar roadways are shiny. Easy sell.
I wrote about the budget-oriented logic of getting a solar roadways _project_ in a blog post here:
http://sitacuisses.blogspot.com/2016/07/a-rational-case-for-solar-roadways.htmlAnd for visual learners here's a picture:
https://www.flickr.com/photos/josecamoessilva/29632160643Cheers,
JCS