This Tech Can Cool the Planet Without Electricity

UCLA Professor Aaswath Raman and his team developed a thin, mirror-like film that can lower the temperature of objects by more than 10 degrees without using any energy.

The patented film reflects sunlight to keep surfaces and contents cool. It can be applied to roof panels, refrigerated trucks, and batteries. It mimics radiative sky cooling, a natural process in which objects emit thermal radiation into the cold sky so they don't heat up.

It saw 10 to 20% efficiency gains in grocery store pilot tests. One store in Stockton, California, saved roughly $5,800 in annual electricity.