Described as “the world’s first ever photovoltaic road surfacing material”, Colas’ Wattway will begin trialling in the UK next year, at up to three different sites, it was announced in late November. This follows the first trials of the material, which are underway in France.
Seemingly designed and tested to endure vehicles continuously passing over the road surface, the panels are 7mm thick and are applied to the surface using a high performance resin. A glass bead resin coating is also applied to allow the surface to provide acceptable frictional performance without significantly affecting the solar panels efficiency.
The power generated by Wattway has the potential to be used for highways and transportation infrastructure, such as Variable Message Signs and street lights, but also could be returned to the grid or used to supply energy to nearby homes and businesses. It is particularly suitable for use with smart grids and short-circuit electricity production, says Colas.
Carl Fergusson, Colas Executive Director Strategy & Development, said: “Without doubt this is an extremely exciting time for the industry and we are looking for a number of forward-thinking clients who are interested in running Wattway trials with us. The UK trials will form part of about 100 trials taking place world-wide.”
Data will be gathered on Wattway’s functionality in parallel with the site requirements, as well as on how efficiently it generates energy. This will be shared with Colas’ Campus for Science and Technology (CST) near Paris, where Wattway was developed over a five-year period in conjunction with other key partners and where the innovation is now being pre-industrialised for a full scale global launch from 2018.
Each solar panel is comprised of an array of 15-cm wide cells making up a very thin film of polycrystalline silicon that transforms solar energy into electricity. These extremely fragile photovoltaic cells are coated in a multilayer substrate composed of resins and polymers, translucent enough to allow sunlight to pass through, and resistant enough to withstand even large vehicle traffic.
According to Colas, the composite and watertight “sandwich” is also designed to adapt to the pavement’s natural thermal expansion. The surface that is in contact with vehicle tyres is treated to ensure skid-resistance equivalence to conventional asphalt mixes. Electrical connections can be installed at the edge of the carriageway or in ducts integrated in the panels themselves. Lastly, electronic circuit breakers ensure safety.
“The trial sites will allow us to experiment with different ways to use this innovative technology and the feedback will help us validate the most appropriate solutions for our market. By reviewing feedback from our UK trial sites, will allow us to validate the most appropriate solutions for the UK market, which will ultimately help build our offers for full scale launch as of 2018,” said Fergusson.
Colas, the firm behind the technology, is a subsidiary of French engineering company Bouygues.
Anyone interested in taking part in the trials or to find out more information is asked to email project.engineering@colas.co.uk.