Sustainable Energy

This highway can be quiet, bright and full of energy

Anmar Frangoul | Special to

Researchers at the Eindhoven University of Technology have developed a system that has the potential to kill two birds with one stone: large colourful noise barriers for highways that also generate solar energy.

"They are basically large luminescent solar concentrators (LSCs)," Michael Debije, from the university's Department of Chemical Engineering and Chemistry, told CNBC via email.

"That is, they are large sheets of plastic filled with a fluorescent dye," he added.


Debije said that the fluorescent dye absorbs part of what he called, "the incoming solar spectrum," with the dyes re-emitting this light at a longer wavelength.

Debije went on to explain that a process called 'total internal reflection' enables a large part of sunlight to be trapped within the plastic plate.

"The light then travels through the plastic plate and exits from the thin, narrow edges," he added. "Along these edges we place thin strips of solar cell material to convert the edge emitted light into electricity."

Debije said that advantages of the barriers include their transparency, the plastic's toughness and the fact that they, "are less adversely affected by changing light conditions."

In June a test was launched on the A2 highway near the city of Den Bosch, "to assess the economic and technical feasibility of this form of energy generating noise barriers." The study was being led by construction company Heijmans, according to a release from the university.

Debije explained that it was hoped the trial would inform researchers about "how well the LSCs perform under different lighting and weather conditions," as well as offering insight into stability issues and gauging public opinion on the concept.

But because the panels are not as efficient at producing energy as a conventional photovoltaic solar panels, Debije said that he saw the LSCs primarily as part of a building or construction -- such as walls and sound barriers – and "secondarily as an electricity generator."

"The electrical output of an LSC will always be lower than a solar panel," he added. As such, in locations where space was at a premium and aesthetics were of less importance, such as a rooftop on a family home, Debije recommended using a normal solar panel.

"Everywhere else, you could use the LSC: think large areas, (they would be) attractive objects providing a primary function and giving some electricity as well."

Debije's university is no stranger to sustainable innovations.

Solar Team Eindhoven – made up of students from the university – have developed solar powered cars, the most recent of which is the Stella Lux.

The team says that the car generates more power than it consumes and can travel up to 1,000 kilometers (622 miles) on a sunny day.