Sweating paint
-
A cool house without air conditioning may soon be possible.
Scientists in Singapore have developed a new type of paint that reflects sunlight and cools surfaces by slowly evaporating water. Unlike other commercially available cooling paints, which are designed to repel water to protect the underlying material, the new one even works in hot, humid places, offering a low-energy way to stay cool, researchers report June 5 in Science.
“The key is passive cooling,” which requires no energy input, says material scientist Li Hong In other words, it works without using electricity or mechanical systems. Right now, radiative cooling is the most common type of passive cooling used in materials, including certain paints. It works by reflecting sunlight and radiating heat from a surface such as walls or roofs, into the sky.
