In a study published in Science Bulletin, a group of international researchers have created a natural fabric that city dwellers could wear to combat the rising temperatures brought on by concrete, asphalt, and buildings in cities globally.
Image Credit: tete_escape/Shutterstock.com
As heatwaves become more promiment, cooling textiles that can be used in clothing, shoes, hats, and even building surfaces offer insights into a time when our cities may not require greenhouse gas-emitting air conditioners.
The wearable fabric, according to engineers from Zhengzhou University and the University of South Australia, is made to reflect sunlight and let heat escape while obstructing the sun's rays and reducing the temperature.
With fewer green spaces and warmer, more uncomfortable temperatures caused by global climate change, the fabric promises to provide relief to millions of urban residents.
According to Yangzhe Hou, a visiting researcher at UniSA, the fabric makes use of the radiative cooling principle, which is a natural process in which materials release heat into the atmosphere and eventually into space.
Unlike conventional fabrics that retain heat, these textiles are made of three layers that are engineered to optimize cooling.
Yangzhe Hou, Visiting Researcher, University of South Australia
Heat can be effectively radiated through the upper layer, which is made of polymethyl pentene fibers. The middle layer, made up of silver nanowires, improves the fabric's reflectivity, preventing more heat from reaching the body. The bottom layer, made of wool, draws heat away from the skin, keeping wearers cool even in the hottest urban environments.
In our experiment, when placed vertically, the fabric was found to be 2.3°C cooler than traditional textiles, and up to 6.2°C cooler than the surrounding environment when used as a horizontal surface covering. The fabric’s ability to passively reduce temperatures offers a sustainable alternative to conventional air conditioning, providing energy savings and reducing the strain on power grids during heatwaves.
Yangzhe Hou, Visiting Researcher, University of South Australia
According to Zhengzhou University researchers Jingna Zhang and Professor Xianhu Liu, the technology not only tackles the immediate problem of urban heat islands, but it also contributes to larger efforts to mitigate climate change and transition to more sustainable urban living.
It is hoped that the technology will be modified for even more extensive applications such as outdoor furniture, urban planning, and construction materials.
Although the fabric has a lot of potential, scientists say the current production method is expensive and that more research and government support are required to ensure the textiles’ long-term durability before they can be commercialized.
“Whether consumers are willing to pay more for wearable fabrics depends on the cooling effect, durability, comfort, and their environmental awareness,” the researchers concluded.
Journal Reference:
Liu, X. et. al. (2024) Radiation cooling textiles countering urban heat islands. Science Bulletin. doi.org/10.1016/j.scib.2024.09.008