Ooh, That Road Is Hot

Here's an ingenious design that allows roads to double as solar collectors for heating an office building. In summer pipes crossing under the surface of the road heat water from the hot asphalt, which is then piped to an underground aquifer 100 meters below the surface. Heat exchangers there allow the heat to be stored underground until winter, when the circuit is switched. The heated water is then used to heat an office building before passing back under the road where residual heat keeps the road free of ice and snow. When the temperatures approach freezing, the water is pumped back down to the aquifer again. An added benefit is that the system actually helps cool the road in summer, saving wear and tear on the asphalt. The system is was designed by Arian de Bondt, an engineer for the Dutch building firm Ooms, and is functioning at their office in Scharwoude.

Read the full Economist article here.

P.S. It looks like "The Economist" is featuring a small section of green technologies. They also report on an idea, which is in the research stages, for using algae to recapture carbon coming out of smoke stacks. The algae could be dried and then put through the plant again or converted to biodiesel. They also have this article about the quest for a longer-lasting, lower energy light bulb.