Heat From The Street

Ever find your street so hot that you could fry an egg on it? A team of URI professors are interested in using heat from the pavement to power streetlights, melt ice, heat buildings, and illuminate signs.

“We have mile after mile of asphalt pavement around the country, and in the summer it absorbs a great deal of heat, warming the roads up to 140°F or more,” said K. Wayne Lee, professor of civil and environmental engineering and leader of the joint project. “If we can harvest that heat, we can use it, save on fossil fuels, and reduce global warming.”

With Chemistry Professor Sze Yang and graduate student Andrew Correia, Lee has identified four approaches.

One of the simplest is to hang flexible solar cells over the top of Jersey barriers to power streetlights and illuminate road signs.

Another practical approach would be to embed water pipes beneath the asphalt. The sun-heated water could be piped beneath bridge decks to melt ice and reduce the need for road salt.

A third approach uses thermo-electricity produced with semi-conductors when hot and cold temperatures meet. With thermo-electric materials embedded in the roadway, enough electricity could be generated to defrost roadways.

Perhaps the most futuristic idea is to completely replace asphalt with large, durable electronic blocks that contain solar cells, LED lights, and sensors.