About 10 percent of all electricity consumed in the United States is used for air conditioning, according to the U.S. Department of Energy. As we seek to lower energy consumption to combat global warming, raising our thermostats in hot weather or lowering them in cold weather is a simple action we can all take. The good news is that one company is launching new fabrics that can make taking such steps much more comfortable.
In early November, apparel startup LifeLabs Design launched their patented CoolLife fabric, which they say can lower a wearer’s skin temperature by nearly 4 degrees Fahrenheit. At the same time, they began offering jackets and vests made from their WarmLife fabric, which they report is 30 percent warmer than clothing of comparable weight and bulk. While the benefits from the fabrics to runners and outdoor adventurers are obvious, their real potential lies in allowing society to reduce energy costs associated with heating and cooling in public and private spaces.
The secret to the new cooling fabric is a surprising one: it is made from polyethylene, the type of plastic found in cling wrap and the thin, transparent bags shoppers fill with produce at the grocery store. It turns out that polyethylene allows 100 percent transmission of infrared radiation, one of our body’s most important cooling mechanisms. (Infrared radiation is what makes us visible in the dark to someone wearing night vision goggles.) Most clothing traps infrared radiation against the skin, but it passes right through the CoolLife apparel.
The new fabric stems from research done at Stanford University and detailed in a 2016 study published in the journal Science. The Department of Energy-funded work showed that skin temperature was reduced by nearly 4 degrees Fahrenheit when covered by polyethylene compared to when it was covered in cotton fabric. Polyethylene allows the transmission of infrared radiation because of its very simple carbon and hydrogen molecular structure, says professor Yi Cui, one of the authors of the study and a co-founder of LifeLabs. “We proved that polyethylene, one of the most common plastics in the world, can cool the human body,” he says. “Then we had to make viable clothing out of it.”
Cui knew that LifeLabs couldn’t simply drape people in clingy, transparent plastic film, so through a business incubator they began work on devising a fabric that is, he says, “breathable, feels good on the body, stretches so that it doesn’t break when you put it on, and is washable many times and still feels good to wear.”
To meet those requirements, they ultimately turned to the same techniques that have been used to make plastic-based fabrics like polyester for decades—the polyethylene is extruded into a yarn, and then woven into a fabric. The problem was that polyethylene had never before been used for apparel, so the team had to solve the fact that it has an extremely low melting point, just half that of nylon for example. They worked with several suppliers before they found one who extrude a yarn that was elastic enough, and not brittle.
The bigger problem was that weaving machines typically generate temperatures high enough to melt the polyethylene yarn the LifeLabs team was working with. Eventually, they landed on running the weaving machines at slower speed. “It’s not sexy, but we solved those problems by being in the mills and factories and working with them until they got it right,” says LifeLabs Design CEO Scott Mellin, who joined the company this year from athletic apparel company The North Face. Mellin says that LifeLabs worked with seven or eight suppliers across several countries before they achieved fabrics ready for the marketplace.
The Stanford group isn’t alone in investigating the cooling properties of polyethylene for apparel. Researchers from MIT have been experimenting with the plastic since at least 2016, and in March of this year published a study in the journal Nature Sustainability detailing their work turning the plastic into woven fabrics.
“We strongly believe that adoption of PE textiles will be very beneficial for the world from the sustainability standpoint,” says Svetlana Boriskina, one of the MIT study’s authors. She wouldn’t comment on LifeLabs’ new fabric, but affirmed that her team had received a patent for their own fabrics, branded Svetex, and are working to commercialize them through MIT-based startup Nermaco.
Similar to LifeLabs, the authors of the MIT study say that in addition to their cooling properties, the polyethylene fabrics are also less costly ecologically. Because of its lower melting point, they say, it takes less energy to produce the yarn. Using the Higg Materials Sustainability Index developed by the Sustainable Apparel Coalition, Boriskina’s MIT team has calculated that polyethylene fabrics have a lower ecological footprint than polyester, and even wool and cotton, which both require large fuel costs to transport and process, and considerable water to wash and dye. Both the LifeLabs and MIT products are solution-dyed, a method of introducing dyes to the plastic before it is extruded, which requires far less water than traditional dying techniques.
In addition, the MIT group points out that because polyethylene constitutes such a large percentage of single-use plastics, fabrics made from the stuff provide a significant opportunity for recycling. LifeLabs says they are finalizing prototypes of CoolLife apparel made from recycled polyethylene. WarmLife jackets and vests are already made from 97 percent recycled materials.
The WarmLife fabric works thanks to reflectivity. The skin-facing side is coated with a microscopic metal layer that reflects the body’s infrared radiation, and in the case of the jacket, traps that heat inside an inch-thick layer of insulation (mimicking, ironically, the greenhouse gas scenario that is causing climate change.) The concept of reflective fabrics isn’t a new one—NASA used it in their space suits as early as the mid-1960s—but LifeLabs’ version provides the breathability that makes such garments much more comfortable to wear. To create the breathability, LifeLabs is using a technique they call “nanocoating,” few details of which they would divulge but which apparently coats the individual fibers, leaving plenty of space for moisture to pass through.
Niclas Bornling, a 20-year veteran of the apparel industry currently working for Swedish brand Houdini Sportswear, was an early tester of the CoolLife fabric. “It definitely works,” he says. “There’s an immediate feeling that it’s cooling you down.” Bornling also tested samples of CoolLife sheets. “They worked so well that my wife was too cold sleeping, and we haven’t been able to use them since,” he says, “but I’ve kept using the pillowcase on my side.”
As for LifeLabs’ claims that their cooling fabric can help fight climate change one thermostat at a time, to Bornling, that depends on how widely it is adopted. “I’m happy to see that this is happening,” he says. “It has a lot of promise, but it depends on how widely available it becomes.” Imagine, he says, applications like CoolLife in car seats—air conditioning use can lower your car’s fuel economy by up to 25 percent. Or, says professor Cui, home draperies made of the reflective WarmLife fabric.
Wide distribution is in the works, says LifeLabs CEO Mellin. In addition to selling products through its own label, the company is working on inking partnerships with some household name brands for global distribution, which is where wide adoption would occur, and a real difference could be made both in terms of energy consumption and social equity.
“It’s not just for athletes and office workers,” he says. “I’m envisioning apparel for factory workers who don’t have AC, or even burkas made from CoolLife. Climate change isn’t going to wait for us to become a $100 billion brand.”