Material inspired by an ant could cool buildings, reducing the need for air conditioning.
Researchers at Columbia University are working on a new way to keep buildings cool. They drew inspiration from an unlikely source: a heat-tolerant species of ant called the Saharan Silver Ant, which lives in the scorching desert.
In 2015, physics professor Nanfang Yu discovered that this ant's silvery coating of hair reflects sunlight and radiates heat back to the sky. "They are only active in the middle of the day when the surface of the desert is the hottest", explains Yu.
Now, he and his colleagues have developed a paint-like material that mimics these functions. When applied to a rooftop, it reflects up to 99% of sunlight, and emits heat back to the atmosphere. Yu says that helps cool the building underneath and it does so far more effectively than white paint, which only reflects certain wavelengths of solar radiation.
He says more research and testing is needed before this technology is widely available. But if successful, it could help reduce the need for energy-intensive air conditioning: "If you put this coating on the top of the roof, that may translate into a saving of electricity in the summertime", says Professor Yu.