The SolaRoad project has been in the works since 2009, when the Netherlands Organization for Applied Scientific Research (TNO), led a team of road construction and technical service providers to explore the solar potential of Holland's roads. It estimates that the 140,000 km (87,000 mi) of roads in the country provide between 400 and 500 km sq (154 - 193 mi sq) of surface area that could potentially be tapped for solar power.
To start out, a 70 m (230 ft) long bicycle path with embedded solar panels will open on November 12. Pre-fabricated concrete slabs measuring 2.5 x 3.5 m (8.2 x 11.5 ft) make up the path and feature a layer of crystalline silicon solar cells with a 1 cm (0.4 in) protective layer of tempered glass on top. The team says that this top layer is translucent so as to allow the sunlight through, while also strong enough to provide a safe road surface.
Over a three-year period, the team will conduct testing to ascertain exactly how much energy the road is capable of generating as well as gauging the safety of the road in different weather conditions. Energy generated by SolaRoad will be directed back into the grid, with the team anticipating it could one day power traffic installations, road lighting, homes and electric cars. It hopes to extend the path to 100 m (330 ft), a length the team estimates will provide enough power for 2-3 homes.
SolaRoad is not the first project aimed at turning roads and pathways into energy-harvesting surfaces. This year the US-based Solar Roadways team has been gathering steam in its bid to replace regular asphalt with solar panels. The company received a contract to develop a prototype of its solution, which it then followed up on with an operational solar power parking lot.
There are some slight differences in their approach. Solar Roadways is unashamedly thinking big picture, integrating programmable LEDs to form custom roadsigns, heating elements to stave off ice and snow, and special corridors to house fiber optic and TV cables.
By channeling its energy into the bicycle path pilot, SolaRoad is aiming to establish maximum solar efficiency on a small scale first. It says this more cost-effective strategy will see money saved for further development down the (solar-powered) road.
The Dutch language video below gives an overview of the project.