An Unexpected Source of Energy?

The article Scorching asphalt and solar power is a good report on the potential use of asphalt to extract energy. Asphalt has some obvious advantages which include the fact that it is a key component of roads and a good conductor of heat. Researchers at at Worcester Polytechnic Institute are investigating a means of harnessing absorbed heat and using it as an energy source. Up to this point technology is too expensive for widespread use but if technology becomes affordable their are plenty of asphalt roads which would need to be repaired and repaved in the future as well as new roads which will be built. Extracting heat from asphalt also would have a cooling effect especially appreciated in big cities.