The Basque technological center Tecnalia is participating in the Pavener Project, an initiative whose goal is to make use of the solar energy that resides in pavement, in order to employ it heating and cooling buildings.
Asphalted surfaces can reach temperatures of up to 70º celsius (158º fahrenheit) on sunny days, and given the large amount of available paved surfaces, there is a great potential to recover this energy.
The Pavener system consists of collecting this accumulated solar energy in pavements, through the circulation of a fluid contained in tubes installed under the surface. This method works in a similar fashion to a solar collector and can be used under any paved surface exposed to sunlight, such as highways, sidewalks, parking lots, runways, etc. The system has numerous advantages, and its development is being led by the Grupo Campezo based in Guipúzcoa along with Tecnalia.
This system allows accumulated solar energy to be utilized in the air conditioning of buildings, athletic and leisure facilities, pools and for hot water. Another potential application of the system is to use it to keep the temperature of asphalt above freezing in winter, therefore impeding the formation of ice on highways. In addition to its benefits for roadway safety, this would reduce the amount of salt required in order to combat ice formation, thereby reducing the environmental impact.
Further, maintenance requirements for highways would be decreased given that, by keeping their temperature stable throughout the year, there would be fewer cracks. Another advantage of extracting excess heat from the ground is to reduce the temperature of cities.
Overall, by utilizing a clean source of energy, the Pavener method would reduce the consumption of fossil fuels, as well as the emissions of greenhouse gases into the atmosphere.