World's 1st Solar Highway Opens in French Village

The world's first solar highway has opened in France, in the not-very-sunny village of Tourouvre au Perche in Normandy. The roadway is just 1-kilometer long, but that still works out at 2,800 square meters of photovoltaic cells—enough to power the village's street lights. The road was built by Colas, a large Anglo-French construction company. Colas has apparently been working on its own solar road tech, called Wattway, for at least five years, Ars Technica reported.

Wattway has been tested in car parks, but this is the first time it has been used on an active road. There will now be a two-year test period, to see if Wattway can withstand the rigor of being pounded by thousands of cars and trucks per day, and whether it can actually provide a useful amount of electricity.

"We are still (in)… an experimental phase," Jean-Charles Broizat, a Wattway director, said in a news release. "Building a trial site of this scale is a real opportunity for our innovation," he added. The main problem with constructing solar roads is their crippling cost. One of the main selling points of Wattway, according to Colas, is that each panel is just a few millimeters thick, and can thus be installed on top of an existing road, which in turn massively reduces construction costs.

Having said that, the 1-km road in Normandy cost $5.2 million (€5 million) to build. Expanding that out to €10 million per kilometer for a two-lane solar road, you are looking at a total cost measured in billions or even trillions of dollars to cover a sizeable portion of a country's roads with solar panels.  The synthesis between solar power and transport is becoming increasingly common. Earlier this year, the Solar Impulse 2 aircraft completed a round-the-world trip powered solely by the sun, while Solar Team Eindhoven – made up of students from the Eindhoven University of Technology – have been designing and developing solar powered vehicles for several years.