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A team engineers has created a super-thin material that could help keep buildings cool. The team is the University Colorado Boulder the USA. Engineers the university developed the revolutionary new material, that is very thin and can cool objects even direct sunlight. The material does not need energy to work nor does it need water to help keep things cool. The engineers say the new material could provide an answer to air conditioners, which are expensive to run and need a lot water. The material is unlike anything found nature. It is a glass-polymer hybrid that is just 50 micrometers thick. That's slightly thicker than the aluminium foil we use cooking.

The engineers explained how their new material works. They said when it is put top of something, two things happen. The first thing is that it cools the object underneath reflecting the Sun's rays into space. At the same time, the second thing happens - the material removes the object's own heat and sends that the air. An engineer said: "The key advantage this technology is that it works 24/7 with no electricity or water usage….We're excited the opportunity to explore potential uses the power industry, aerospace, agriculture and more." Another researcher said: "Just 10 to 20 square meters this material the rooftop could nicely cool a…house summer."

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