David Grossman for Popular Mechanics:  China is building a 1.2 mile (2 km) stretch of solar highway, meaning solar panels on the road will be powering the towns surrounding it. Engineers hope that soon it will wirelessly power electric cars driving on the road as well.

The Jinan South Ring Expressway starts off in the eastern Chinese city of Jinan, home to nearly 7 million people. Known as a tech and transportation hub, it is home to Sinotruck, the county's state-owned heavy-duty truck manufacturer. According to state-owned media, the solar-powered leg of the expressway will be open by the end of December. It will be able to carry up to medium-sized trucks.

To build a photovoltaic highway, Chinese engineers are using three layers. The uppermost of these is transparent concrete with a feel similar to asphalt. Then come the solar panels, absorbing the sun's rays while safely protected from nature. Below the solar panels is a strip of insulation that makes sure nature doesn't interfere from the bottom up.

Beyond acting as a power source, the road also provides an added benefit: The panels heat can transfer through the concrete, allowing them to automatically melt snow.   Full Article: