Roads made of solar panels!

Imagine a world where all the roads, parking lots and bridges are covered with solar panels!
Beautiful, right?

But could it really be?

Yes, it could. The basic engineering of Solar Roadways seems robust and fairly well thought through. Can it be done economically? It’s very difficult to see how.

You have to add a lot of edge use cases together to create a single business case that might be compelling. And then there are all of the problems with the idea that aren’t well thought through.

Roads right now are as cheaply made as possible, and as poorly maintained as possible. That’s because there are too many of them by any reasonable standard and they are expensive to build and maintain.

Solar Roadways make them a lot more expensive — 10 to 40 times more expensive depending on assumptions — and in theory create the ability to avoid some costs and make some other costs more viable, but a lot of the additional value seems pretty flimsy. They will be unable to overcome this massive cost increase through generating electricity.

For example, they want to replace painting road markings — which would degrade the light hitting the solar panels — with LED road markings. Well, this just adds a lot of cost and heat, won’t necessarily be particularly visible during the day and will put LEDs and their wiring between the panels and the sunlight too. Ditto magically moving lane markings allowing shifts in traffic patterns will likewise be an expensive technical solution to some paint which needs to be restored every year or two and maybe some overhead signage.

(Photoshopped image from the Solar Roadways site).

They want to add sensors for crashes and traffic flow and a bunch of other stuff. Of course, most of this can be done easily by traffic camera analysis, cell phone tower data analysis and occasionally by stretching counting hoses across the roads. In other words, they want to replace completely adequate and vastly underutilized existing data streams with expensive infrastructure.

Of course, all of the extra lights and gizmos take power, and the sunlight doesn’t shine all of the time. What happens then? Well, the roadway sucks a bunch of power back from the grid to keep providing road markings, for example. So they talked about integrated storage for a while, which is always a sign of a poorly thought through major infrastructure for renewables, and then they’ve shifted to grid connections for backup which is where they should really have started.