Don’t have AC? This new fabric has you covered during heatwaves

When hot weather strikes, we tend to reach for the coolest items in our wardrobes – favouring loose, white garments or whatever feels most comfortable. 

But engineers from Zhengzhou University in China and the University of South Australia (UniSA) have something more specific in mind for future heatwave dressing: a fabric that can actually lower the surrounding temperature. 

The research team say this fabric could be incorporated into clothes, hats, shoes and even building surfaces, helping to counter the urban heat island effect in cities. 

“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,” says UniSA visiting researcher Yangzhe Hou, one of the authors of the new study published in Science Bulletin journal. 

What is the cooling fabric made of?

The wearable fabric is designed to reflect sunlight and allow heat to escape, while blocking the sun’s rays and lowering the temperature.

Hou says it leverages the principle of radiative cooling – a natural process where materials emit heat into the atmosphere, and ultimately into space.

“Unlike conventional fabrics that retain heat, these textiles are made of three layers that are engineered to optimise cooling,” he explains.

The upper layer is made of polymethyl pentene fibres, which allow heat to radiate effectively. 

Next is a middle layer composed of silver nanowires which enhances the fabric’s reflectivity, preventing additional heat from reaching the body. 

Meanwhile the bottom layer, made of wool, directs heat away from the skin, ensuring that people stay 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,” says Hou.

What potential does the fabric have for dressing cities?

It might sound farfetched to suggest this prototype could reduce the need for greenhouse gas-emitting air conditioners in cities anytime soon. But the researchers see a wide application for their design.

They hope the technology could find its way into construction material, outdoor furniture and urban planning.

Current obstacles include a costly production process. And the researchers say the long-term durability of the textiles needs further investigation and government support before it can be commercialised.

“Whether consumers are willing to pay more for wearable fabrics depends on the cooling effect, durability, comfort and their environmental awareness,” they add.