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

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

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