We all realize by now that global temperatures keep rising and it’s been made worse by human activities.

Places around the world, including urbanized areas, have seen temperature surge. We’ve also seen how more urbanized areas are becoming urban heat islands. It’s a term to describe heat from pavement, skyscrapers, and dense infrastructure that amplifies already high temperatures.

Scientists and researchers have sought innovations to tackle this problem, in ways that won’t make current environmental problems worse. Among those is the development of new fabrics which can get rid of or maybe alleviate the effects of the heat.

Textiles with cooling properties offer us a peek into a future where air conditioners might no longer be needed to cool off urban areas. Materials like these could be used for clothing and even building surfaces, and they could reshape how cities combat rising temperatures.

It all sounds very sci-fi-ish, but there are some fabrics that are in development right now. Here are a few examples.

Fabric that reflects sunlight

Engineers from Zhengzhou University and the University of South Australia have developed a groundbreaking wearable fabric. It reflects sunlight, dissipates heat, and lowers surface temperatures.

Their findings, published in Science Bulletin, showcase a solution to relieve the discomfort faced by millions of urban residents. Global warming and shrinking green spaces have exacerbated heat stress in these areas.

UniSA visiting researcher Yangzhe Hou explains that the fabric utilizes radiative cooling. It is a natural process in which materials release heat into the atmosphere and, ultimately, into space.

Unlike conventional fabrics that trap heat, this textile is composed of three specialized layers designed to maximize cooling efficiency. The first is the upper layer, made from polymethyl pentene fibers that allow heat to radiate outward.

The middle layer is made from silver nanowires. The material enhances reflectivity, deflecting sunlight and preventing additional heat absorption.

Lastly, the bottom layer is made from wool. Per the researchers, wool directs heat away from the skin, ensuring consistent cooling for wearers.

According to Hou, the fabric showed impressive cooling properties during experiments. When positioned vertically, it was 2.3°C cooler than traditional textiles, and as a horizontal surface covering, it was up to 6.2°C cooler than the surrounding environment.

“This passive cooling capability offers a sustainable alternative to air conditioning, reducing energy consumption and alleviating stress on power grids during heatwaves,” Hou said.

This technology, the researchers claim, addresses urban heat island effects. At the same time, it contributes to broader climate change mitigation efforts.

Knowing the potential, the researchers envision applications beyond wearable fabrics, including construction materials, outdoor furniture, and urban infrastructure.

But making it come true is not quite easy. The production process is currently expensive. Moreover, the long-term durability of the fabric requires further research and government backing before large-scale commercialization can happen.

“Consumer adoption will depend on factors like the fabric’s cooling efficiency, durability, comfort, and environmental impact,” the researchers note.

Chalk-based fabric coating with cooling properties

Another innovative type of fabric was presented in August by a graduate student at the University of Massachusetts Amherst and their team. They presented their research at the  American Chemical Society (ACS).

The researchers said that when there’s sun exposure on our body and clothing, they absorb ultraviolet (UV) and near-infrared (near-IR) light, causing us to heat up. Meanwhile, our body naturally generates heat, which can make things worse.

Previously, scientists have developed solutions which  incorporate synthetic particles like titanium dioxide or aluminum oxide or use organic polymers such as polyvinylidene difluoride. Those require forever chemicals for production. The researcher said that scaling these materials for commercial use is not sustainable.

Inspired by the historical use of limestone-based plasters to cool sunny homes, the researchers developed a novel method.

It integrates calcium carbonate (found in chalk and limestone) and biocompatible barium sulfate into a polymer coating. The coating is applied using chemical vapor deposition (CVD).

CVD is a technique previously refined by Andrew’s team. It allows for durable polymer coatings on fabric through a streamlined process that minimizes environmental impact. The new approach can reflect visible and near-IR light and barium sulfate particles which block UV rays.

According to their testing,  treated fabrics reduced temperatures by up to 8°F compared to ambient air and were 15°F cooler than untreated fabrics. One of the researchers said that subjects underneath the sample felt cooler than under the shade.

For a durability test, the researchers simulated the wear and tear of washing. The mineral-polymer coating maintained its cooling properties and stayed to the fabric.

The research team is in the process for larger production. Since it’s a coating, the team believes that it’s applicable to almost any commercially available fabric.

“Without requiring any power input, this technology can help people stay cool in extremely hot environments, making it a valuable solution in regions facing rising temperatures,” said one of the researchers.

Cooling textiles suitable for urban heat islands

Published in Science journal, researchers at the University of Chicago’s Pritzker School of Molecular Engineering (PME) have developed a fabric to improve heat in urban areas.

In outdoor tests under Arizona’s scorching sun, the fabric demonstrated remarkable cooling effects. It maintained a temperature 2.3°C (4.1°F) cooler than fabrics used in outdoor sports and 8.9°C (16°F) cooler than commercial silk often worn in summer clothing

 

Co-first author Ronghu Wu emphasized the need to consider the real-world environment when designing cooling textiles.

“People typically focus on material performance in lab conditions, but in real life, only about 3% of clothing faces direct sunlight—on hats, shoulders, and shoe tops. The rest is exposed to thermal radiation from surrounding structures,” Wu said.

The researchers said that the engineering challenge was  creating a fabric capable of addressing both heat sources.

“Solar heat is visible light, while thermal radiation is infrared, each with different wavelengths. We had to fine-tune the material to handle these distinct optical properties simultaneously,” explained co-first author Chenxi Sui.

The new textile reduces reliance on energy-consuming cooling systems. The fabric, which has received a provisional patent, can be adapted for various uses beyond clothing.

A thicker version, enhanced with an invisible polyethylene layer, could be applied to building exteriors and vehicles, reducing internal temperatures and lowering energy costs.

In addition, the material could be used to store and transport perishable goods, such as milk, by minimizing refrigeration needs.

“This passive process can save significant cooling, electricity, and energy costs,” said Sui.

The bottom line for these researchers is that by addressing urban heat from multiple angles, this innovative fabric could play a vital role in making cities more livable and sustainable amidst global climate challenges.

Moreover, the researchers hope the fabric can help prevent heat-related hospitalizations and deaths.

 

Sources

https://www.sciencedaily.com/releases/2024/10/241009215428.htm

https://www.sciencedaily.com/releases/2024/08/240821124457.htm

https://www.sciencedaily.com/releases/2024/06/240613161204.htm