My best guess would be that this to test if solar works at all on roads. There were talks of this being really useful on Highway at non-peak hours.
If you end up setting Solar Farms, you're grabbing land from Nature. This way you can re-purpose the land already used (roads, footpaths, Highways) for more than moving person from point A to point B.
Also, it allows roads to be productive even when there's no traffic.
One of the reasons is because of the sheer size of roads. It's kind of a strange facet of our economy, one which may shift this century [0], but as it stands roads tend to outweigh buildings in terms of surface area in most countries.
This is interesting because contrary to popular science which says that we can power the whole world with a tiny fraction of land use dedicated to solar panels, surface area is actually one of the biggest challenges we have in a 99% sustainable energy world that we have to get to.
Check out without the hot air, free book by physicist McKay at Cambridge. He's done a 1h presentation at Harvard which tells you the gist of it, and a 15 minutes TED talk which I'd skip unless you really only have 15 minutes. He covers the surface area challenges of solar and other sustainable energies quite well.
The ability then to one day put extremely cheap solar (e.g. at least 1 order of magnitude cheaper than today) in every new road (whose lifespan is a few decades, so we could on paper replace them all halfway through the century), is very interesting.
Of course there are huge, huge drawbacks. But that's not necessarily because it's impossible, but because we have path dependency. That's why you need prototypes and R&D to see how we can build roads sustainably using new materials, and whether solar panels fit into that picture.
[0] Roads are there for a reason: transport. We're now seeing for the first time ever tools on a scale that can cut down transport on a global scale. Still immature, but it's getting there. The combination of internet, 3d printing and virtual/augmented reality, means we can live global lives locally without having to physically transfer ourselves, information or products. It means we can work & study remotely better and experience entertainment and tourism more locally. And when we do move stuff, there's the option of doing it through new channels (air, with drones), or more efficient channels (self-driving vehicles that can attain higher speeds with smaller gaps safely, calculate more efficient routes and turn transport into a commodity: smaller vehicles transporting people, as opposed to cars being branded products, all of which lead to far fewer roads being necessary). It's a very bold claim but I wouldn't be surprised if roads kept explosively increasing until 2025, and then stagnating and at some point sharply reducing after a shift in human culture, manufacturing and transportation.
The company leading the project claims commercialization is five years away. They likely are optimistic or biased, but I am not sure they are outright lying.
Prices of solar cells drop fast. Extrapolate a few years, and costs of solar installations will be dominated not by what solar cells cost, but by what it costs to install them.
In this case, something must be installed anyways to build the cycle path. It might well be that installing a (cycle path, solar cells) combination will only be marginally more expensive than installing a traditional cycle path.
Will we get there? If solar cells and the electronics needed to wire than together (which, in this case, are more complex because the road may see highly variable shading patterns) get dirt cheap, we might.
Do you really believe that it is more efficient to build a bike lane paved with solar panels, rather than a bike lane paved with asphalt and separate, dedicated solar facilitates?
EDIT: Looking at the pictures others have posted you still have to use asphalt (or more likely concrete because you need better stability, which is even more expensive) underneath, so there really is nothing saved by doing this. What a waste of money.
How is the presence of asphalt underneath an issue? The deciding factor will be whether the marginal cost of a solar path over an asphalt path will be greater or less than building an equivalent solar facility. That seems like it could go either way.
Very good point. Plus even if the marginal cost is lower than a dedicated solar facility, we don't necessarily have that luxury. We do if we want just 5% sustainable energy, not a problem. But if we want 99% sustainable energy, surface area is a very tricky challenge [0] and so it'd be a matter of the one and the other, instead of the one or the other.
>The arguments about this thing not making any sense aren't so far away from the arguments about my basement not being very sunny.
Actually, they are. At its best, getting sunlight in your basement is impossible. For solar bike lanes, the worst possible outcome is that they are impractical. And that is a purely financial consideration. At some point the benefits of solar (regardless of cost) might outweigt the negatives of using fossil fuel.
If you end up setting Solar Farms, you're grabbing land from Nature. This way you can re-purpose the land already used (roads, footpaths, Highways) for more than moving person from point A to point B.
Also, it allows roads to be productive even when there's no traffic.