Siphoning Roadway Heat? It’s Not Our (As)phalt!
At the University of Rhode Island, scientists are warming up to ways to capture the heat trapped in roadways.
For over a century, North Americans have been driving on asphalt roadways, all the while not realizing that a potential goldmine of energy was pulsing beneath their tires. Due to both the sun's glorious rays and the continual flow of traffic over their surface, asphalt roadways can heat up to over 140 degrees, heat which is simply pumped out into the surrounding atmosphere.
But in a world that is desperately trying to catch the dream of green that will save us all from possible self-annihilation, Rhode Island scientists have begun examining 4 ways to help harvest this radiating road energy.
They range from the “possible now and being tested” to the “this would be super-cool but insanely expensive” – an excellent way to run the gamut of scientific enterprise.
The first is to use flexible solar cells and simply “hang” them over cement Jersey barricades. Their flexible nature would let them soak up the sun no matter its position in the daytime sky, and their stored energy could be used to power streetlights. This one is simple and potentially effective, and is going to be undergoing testing at the Rhode Island campus in short order.
The second option is to stick water pipes underneath the asphalt and let them heat up. This heated water could then be sent underneath bridges and other icy surfaces to melt the crusty cold substance and limit the need for road salt. So long as the road can absorb enough heat in winter, this could work, but we’ve got to admit to some skepticism on this one.
Number three is a bit more futuristic – using the thermo-electric effect to produce power. If the right kind of semiconductors are joined to form a circuit between a hot and cold area, a small electric charge will result. The theory is that by burying semiconductors at different depths, this effect could be harnessed en masse and used to generate power.
Last but not least is replacing the roadways themselves with electronic blocks containing a host of materials – from solar cells to LEDs – in order to generate power. This idea is in its infancy, and a driveway built of these by an Idaho company cost upwards of $100,000. Plus, we’d imagine that damage to them couldn’t be repaired with two guys in dirty coveralls spraying hot sealant.
While there’s no standard way to use this massive amount of road-heat just yet, the future looks bright for things like green-powered streetlights and self-melting ice on bridges.
As with any potential scientific solutions, these aren’t yet concrete.
Photo Credit: Solar Roadways