Current Affairs » The road that powers its own street lights!

The road that powers its own street lights!

Can a road generate enough power from solar energy for its street lights? This is the question France is trying to answer, with a 1 km. stretch of street paved with 2,880 resin-coated solar panels in the small Normandy town of Tourouvre. The two year, $5 million Wattway surface was funded by the Ministry of Environment.

The project was carried out by French civil engineering firm Colas, a subsidiary of the construction giant Bouygues. Colas says that theoretically, France could become energy independent by paving only a quarter of its 1 million km (over 621,000 miles) of roads with solar panels.

It is estimated that the road will produce about 280 megawatt-hours of energy per year: enough power to light every street in the town where it is installed. The ministry has plans to expand the project to the whole country. But first the Wattway will have to prove that the solar panels can survive the strain of thousands of motorists, especially big trucks, on them every day. It is also a concern if the Wattway can withstand the ravages of time and weather.

One drawback of the system, which sceptics are quick to point out, is that solar panels are more effective when angled toward the sun, typically on slanted rooftops, than when they are laid flat.

Another issue is the cost. Each kilowatt-peak — the unit of measure for solar energy — that is generated by Wattway currently costs €17, compared to €1.30 for a major rooftop installation.

However, Colas is not discouraged. It hopes to make the project cost competitive by 2020, and notes that the cost of producing solar energy decreased by 60 percent between 2009 and 2015.

Wattway Director Jean-Charles Broizat has stressed that it is an experimental phase. The two critical factors to consider will be the lifespan of, and the output of energy from, the Wattway. In the next two years, which is the test period, the Wattway will be under intense scrutiny regarding its lifespan and output.

The idea behind the Wattway project is that roadways are occupied by cars only about 20 percent of the time, and so roads are vast expanses of surface that are free to soak up sunlight and convert it to energy. The technology is under exploration in other countries also, such as Germany, the Netherlands, and the United States.

The Environment Minister Segolene Royal said that one of the advantages of the Wattway is that it produces electricity without taking up new real estate. The minister has announced a four year plan for the national deployment of solar highways with projects on the anvil in Brittany in the west and Marseille in the south.