Renewable energy is all the rage today - and for good reason too - we are in the throes of an impending energy crisis, the likes of which we have never had to contend with. It is imperative that we find newer and cleaner ways to find energy. One good thing that comes out of this kind of a high-stakes, do or die situation is that it is an ideal breeding ground for radical innovation.
Make no mistake, radical innovation is exactly what we need if we are going to find a way to survive what’s ahead of us.
Hey, there’s no need to get grim though. We bring good news
A team of researchers from the University of California- San Diego have designed a smart shirt that generates electricity from the wearer’s sweat and movements. This “wearable microgrid” shirt uses biofuel cells that are powered by sweat in tandem with triboelectric generators that are motion-powered.
The shirt harvests energy from both sweat and movements and employs supercapacitors to store said energy.
All the fancy gadgetry is screen-printed right onto the material, including the waterproof circuitry that is made of silver. More importantly though, everything that goes in the sihrt is flexible, stretchy, malleable and washable - however, while we’re on the topic of washable, we need to add a caveat - in its current form, the shirt can’t handle detergents.
Let’s get all science-y for a minute and see how this shirt works
Inside the shirt, at the level of the chest, is the battery pack comprising the biofuel cells. These biofuel cells contain enzymes that catalyse an electron transfer between two molecules found in human sweat - lactate and oxygen. This electron transfer process makes for a steady low-voltage electri current which is then stored in the capacitor for future use.
While all this is happening, the triboelectric generators are busy doing their own thing. The triboelectric generators in the shirt each consist of two pieces of material - one that is negatively charged, placed on the inside of the wearer’s forearm and one that’s positively charged, placed on the wearer’s flank. As the wearer walks or runs, the swing of their arms causes these two pieces of material to rub against one another, which results in pulses of high-voltage electricity being produced. And then, much like the power electricity generated by the biofuels, this current is also fed into the capacitor to be stored.
This research was headed by Prof.Joseph Wang of the University of California-San Diego along with PhD student Lu Yin. They published a paper on the research in the well known scientific journal Nature Communications.
When the team conducted a trial on a volunteer who wore the shirt - first while running and then on a stationary bike - they found that when the volunteer performed either of the mentioned activities for 10 minutes followed by 20 minutes of rest, the shirt was able to continuously power either an LCD wrist wearable or a small ECD display. Interestingly, in both cases, the shirt could keep the devices powered for the entirety of each 30 minute session - i.e even during the resting phase.
That may sound like a lot now but make no mistake, this is some seriously innovative stuff.
In just a few more iterations, this energy harvesting shirt could easily be used to power performance trackers and fitness wearable devices worn by athletes. And once it undergoes enough development to add to its capabilities, these energy harvesting shirts could potentially be worn by all of us as a means to harvest energy from all our everyday movements and sweating.
The future of energy harvesting and wearable smart clothing technology is looking interesting indeed.