The city where almost all road and sidewalk coverage has a dark color, on a hot summer day turns into a heat islands, absorbing asphalt, roof tiles and the entire solar heat. In an average city sidewalks occupy about 35-50% of the total, with almost half of parking lots. They are incredibly warm, only adding to the thermal effect in urban areas.
To solve the problem of heat islands, which include all the cities, without exception, researchers from Berkeley Lab began to study the technologies of "cold pavement." Like the "cold roof", which, thanks to the lighter color tones keep the air inside and outside of the roof cool when reflected sunlight, "cool pavements' can reflect 30-50% of the light of the sun. For comparison, the freshly applied asphalt represents only 5% of the energy of the sun, and the old asphalt 10-20%.
A dedicated group of "Hot Island" explores the properties of the new coating on one of the temporary parking lots in the Berkeley Lab. Parking on the experimental use of six types of new coatings manufacturers Emerald Cities Cool Pavement and StreetBond, imposed directly on the old. Other manufacturers soon intend to provide their developments sidewalk coverage, saving the city from the heat, so strongly influences the ecological situation in the developed countries.
"Cold pavement" made from either traditional materials (cement concrete), but give it a lighter shade for greater reflectivity, or take a special cooling cover, special cooling compounds and placed on top of conventional asphalt. Ideally, researchers would like to get the level of reflection sidewalk solar energy equal to at least 35%.