Traditional air conditioning is hard to install, expensive and sucks up energy. But there's another problem. It may cool down the inside of buildings, but it actually might raise outdoor temperatures, adding to the heat woes in many cities. 

Well, what if there were a way to change that? To lower both inside and outside air temperatures? Enter a new Japanese approach called BioSkin. It wraps buildings in delicate pipes, creating an almost braces-like appearance. When water falls on the roof, it's purified and circulated through the terra-cotta-covered pipes. It then starts evaporating and cooling the air. ‬

‪Skin-covered buildings? Weird, but cool.‬