An engineer at UCLA - Aaswath Raman - has invented a material that reflects most of the radiant heat aimed at it plus it radiates whatever heat is inside it into space. Thus with no moving parts and no expenditure of energy it becomes maybe 10 degrees cooler than the surrounding environment. The Washington Post has the story.
This could be huge as it treats outer space, which is extremely cold, as a heat sink to which unwanted heat is radiated. The SkyCool thin mirror-like film does all of this, emitting infrared light at only those wavelengths to which the atmosphere is transparent.
It requires an unobstructed view of the sky and relatively clear air to work most effectively, but will radiate even in daylight, when it also reflects incoming infrared. It seems ideally suited for desert climates.
