A new three-layer fabric has a wool bottom layer that wicks heat from the skin to the middle layer made of silver nanowires that block heat from coming in. The top layer selectively emits heat into the atmosphere. The fabric was carefully engineered and the materials tuned to respond differently to visible sunlight and thermal radiation. In tests conducted in the urban heat island of Chicago and under blistering Arizona sun, the material stayed 2.3°C cooler than sports cooling fabrics and 8.9°C cooler than commercial silk used for summer clothing.
A thicker version of the fabric protected by an invisible layer of polyethylene used on the sides of buildings or cars, could lower internal temperatures and reduce air conditioning’s cost and carbon impact, and used to transport and store milk and other foods otherwise spoiled in the heat, cutting refrigeration’s impact.