A survey says that, out of the total electricity consumed by the buildings in the United States, nearly 15 percent of it is due to air conditioning. A group of scientists made research to reduce this huge demand for electricity by inventing a prototype material that can cool an area like the air conditioners do now, but without using electricity.
This material is multi-layered and very thin measuring just 1.8 microns thick. It is made of seven layers of silicon dioxide and hafnium dioxide on top of a thin layer of silver. This material beams heat directly into outer space. The way each layer varies in thickness makes the material bend visible and invisible forms of light in ways that grant it cooling properties. The total material required for each building will depend on the area/size of the buildings to cool the total space.
Image by Peter Vetsch, available under the Creative Common license CC-BY-SA 3.0