Inaugurated in the Netherlands in early November, SolaRoad caught the attention of the media around the world. Despite its modest length of only 70 meters, the new bike path is the pilot project in a much larger energy harvesting innovation.

The idea behind the innovation is quite simple: instead of limiting solar energy to the traditional settings of rooftops and solar plants, roads can be equipped to serve a double purpose, generating energy while the traffic drives by. The electricity can then in turn be used for a variety of purposes from street lights to households and one day, potentially to be channelled to the electric vehicles driving on the road.

It is no coincidence that the pilot project takes place in the Netherlands. The densely populated country is aiming to triple sustainable energy use by 2020 and many of the SolaRoad's advantages are very suitable for the highly urbanized setting with 35 000 kilometres of bike paths alone. Unlike traditional power plants, SolaRoads can be placed close to peoples home, and on expensive land that is in this way easily available for the purpose.

Simply put, SolarRoad turns the surface of a road into a series of solar panels, each measuring just under nine square meters. While solar technology has existed for decades, finding a way to cover the surface with a translucent and dirt-repelling material that also has the crucial features of the traditional surface has been a challenge. To insure safety on roads SolaRoad needs to meet the high standards of durability, skid resistance and reliable function in all weathers.

Right now the hype around the technology is largely limited to the promise it holds, rather than any achievements it has reached. The cost of the construction is still high, and even optimistic estimates expect it to become profitable in ten years time. The project is just entering into a three-year trial period during which data will be collected and analysed to help realize the potential of combining the sun and the streets.