Researchers at The University of Texas at Austin’s Cockrell School of Engineering, alongside scientists from China and Sweden, have created a new material that passively cools itself down.
Image credits Flickr / patrickkavanagh.
The material was inspired by the wing structure of a longicorn beetle species native to volcanic areas in Southeast Asia. The beetles rely on self-cooling tissues to allow them to live in such inhospitable places.
Cool new materials
“Anywhere that needs cooling, this can help,” said Yuebing Zheng, an associate professor in the Walker Department of Mechanical Engineering. “Refrigerators, air conditioners and other methods consume large amounts of energy, but this is cooling by itself.”
While the insect uses its body’s ability to regulate heat and gain access to an environment its competitors can’t live in, the researchers plan to use the new material it inspired to help cool everything from buildings to electronic devices in an environmentally friendly manner.
The researchers first had to determine what gave the beetle (Neocerambyx Gigas, one of 26,000 species of longhorn beetle) its cooling capability. They discovered that their wings are covered in triangular “fluffs” that disperse body heat while also reflecting sunlight.
The team then created a new “photonic film” based on these structures. This film is constructed from common, flexible material (PDMS polymer), and the team explains that it is mechanically strong enough for wide-spread use and easy to manufacture.
The film is applied as a coating on objects and can help decrease temperatures in spaces, buildings, appliances, or electronics without expending energy to do so. In lab tests, it was able to reduce the temperature of items in direct sunlight by up to a respectable 5.1 degrees Celsius (9 degrees Fahrenheit).
It could be put over windows in office spaces or apartment buildings to reflect incoming sunlight, and thus keep temperatures down. It can also be used to protect solar panels from sunlight-induced degradation, or to keep cars cool while parked. In the long run, it could even be used with clothing and personal electronics, the researchers hope.
The paper “Biologically inspired flexible photonic films for efficient passive radiative cooling” has been published in the journal Proceedings of the National Academy of Sciences.
