End of the road for solar panels on roadways?

Solar panel road [image credit: Wattway]

For several obvious reasons cited below, the conclusion should be that solar panels on road surfaces perform extremely poorly and are essentially an irrelevant waste of money. If the money has to be spent, putting the same amount of panels somewhere more suitable would be an easy improvement to make.
H/T Phys.org

Four years ago a viral campaign wooed the world with a promise of fighting climate change and jump-starting the economy by replacing tarmac on the world’s roads with solar panels, says Dylan Ryan at The Conversation.

The bold idea has undergone some road testing since then. The first results from preliminary studies have recently come out, and they’re a bit underwhelming.

A solar panel lying under a road is at a number of disadvantages. As it’s not at the optimum tilt angle, it’s going to produce less power and it’s going to be more prone to shading, which is a problem as shade over just 5% of the surface of a panel can reduce power generation by 50%.

The panels are also likely to be covered by dirt and dust, and would need far thicker glass than conventional panels to withstand the weight of traffic, which will further limit the light they absorb.

Unable to benefit from air circulation, its inevitable these panels will heat up more than a rooftop solar panel too. For every 1°C over optimum temperature you lose 0.5% of energy efficiency.

As a result a significant drop in performance for a solar road, compared to rooftop solar panels, has to be expected. The question is by how much and what is the economic cost?

Continued here.