A radiative cooling technology for air conditioning that leverages the coldness of space could help cut energy consumption – and carbon dioxide emissions – in new buildings up to 70 percent. Skycool Systems believes their unconventional approach to cooling, which uses reflective panels mounted on a building’s roof, can cool structures far more efficiently than traditional air-conditioning systems by harnessing an odd quirk of physics that essentially sends heat back into space.

So how does it work? All objects give off heat in the form of infrared radiation, which is just to the right of red on the visible spectrum. But infrafred emissions in the mid-range literally cast it into the the cool upper atmosphere, allowing the surfaces themselves to dip below the temperature of the surrounding air — think of a pond’s surface forming ice on a clear night when the temperature remains above freezing.

Depending on the installation and climate conditions, the proposed approach could cut the energy used to cool structures by 10 to 70 percent, reducing one of the biggest single demands on the U.S. grid and reducing greenhouse-gas emissions accordingly.

Learn more @ MIT Technology Review