per estimates, there are some 60 million kilometers (37.3 million miles) of
roadways in the world, just sitting there. Past attempts include trying to
convert the vibrations on roads into electricity. But this technology is only
economically feasible on the busiest thoroughfares, which account for a tiny
proportion of the world’s huge network.
heat energy during summer and feed it through the road when the weather changes
to keep it ice-free. There is even a working test-patch in Hiroshima, Japan.
the idea that has gained the most traction in the last few years is to embed
solar cells in roads. In 2014, an American couple launched the Solar Roadways
project and collected more than $2 million on the crowdfunding site Indiegogo.
Their effort, however, is much farther from reality than the Netherlands-based
consortium SolaRoad, which has been operating a 70-meter (230-foot) cycle path
that generates enough electricity for one or two households.
principle is simple. The photovoltaic cells that generate electricity are
protected by glass on the top and supported by rubber and concrete at the
bottom. The glass, apart from letting light through, has properties similar to
asphalt or concrete: it is durable, glare-free, and skid-resistant. Each unit
is connected to a central system, where the electricity generated is fed to the
is a pioneering innovation in the field of energy harvesting. It is a unique
concept, which converts sunlight on the road surface into electricity: the road
network works as an inexhaustible source of green power. SolaRoad is
sustainable and can be used in practice in many different ways.
did not expect a yield as high as this so quickly.” Says Sten de Wit, spokesman
of SolaRoad. “The bike road opened half a year ago and already generated over
3,000 kWh. This can provide a single-person household with electricity for a
year, or power an electric scooter to drive of 2.5 times around the world. If
we translate this to an annual yield, we expect more than the 70 kWh per square
meter per year, which we predicted as an upper limit in the laboratory stage.
We can therefore conclude that it was a successful first half year.”
company claims that a 12-ton truck could safely ride over the road. On the test
road, however, only some 150,000 cycles have put it to the test so far. Apart
from some minor chipping, the roads have continued to work well. The next step
is to build roads in other local councils—maybe even a highway or two.
further in www.solaroad.nl