Imagine a future where the electricity powering your home is generated from the miles of road lining your neighborhood. That’s entirely possible according to French transport giant Colas which has developed a road surface lined in solar cells. Colas is now working with the French government, which has made a pledge to install 1,000 kilometers (621 miles) of so-called solar roads over the next five years.
Colas calls its special road surface Wattway, and according to the company around 200 square feet of the stuff can create enough electricity to power the average home. The normally fragile solar cells are inserted in “superposed” layers within polycrystalline silicon. The resulting surface is said to be not only durable but also grippy.
In development for five years, Wattway is only a few millimeters thick and doesn’t require existing roads to be replaced. It can be applied directly on existing road surfaces, without any need for civil engineering work. There hasn’t been any mention of how much Wattway costs, though, and how long the surface will last before it needs to be replaced.
The idea of solar roads is nothing new. A 230-foot stretch was trialed in the Netherlands in 2014 and showed better-than-expected results. Over a six-month period, the road generated over 3,000 kilowatt hours of electricity—enough to power a single-person household for a year. Until now, though, we haven’t seen a credible solution that doesn't require the existing road surface to be replaced.
Colas is conducting some final tests and, together with the French government, is hopeful of starting installation of Wattway in the coming months.