While you read this, your body is creating energy. You can't feel it happening. But all humans produce fractions of Joules — high amounts when we're physically active, and very low amounts just by existing. And thanks to a few scientists, humanity is slowly gaining the ability to harness that energy.
Before long, we may be able to turn ourselves into walking, talking batteries, powering future technology on the electricity of our mind and muscles.
There's power inside your ear: In 2012, researchers from the Massachusetts Institute of Technology and Massachusetts Eye and Ear Infirmary published a paper on endocochlear potential and its demonstrable use as a future power source for electronic devices. The paper, published in the scientific journal Nature Biotechnology, claimed the researchers were able to insert an energy-harvesting microchip with a wireless sensor into a guinea pig's inner ear to monitor its EP. The idea is that, instead of pacemakers or cochlear implants being powered by a small battery, they could run on the energy your body creates naturally without needing to jam larger capacitors into a person's head to support more demanding electronics.
The findings showed the technology doesn't have to stop there. With further research, EP could help use the body's biological battery to personal electronics, like smartphones, turning the human body into a walking Energizer battery.
Which makes The Matrix look like a fairly accurate, though it's still a terrifying, dystopian prophecy. In the film, the movie's antagonists, sentient robots, have created the Matrix to occupy humanity while they leech human body heat and electrical activity to create giant biological power plants.
It's not as scary as it sounds: As Dr. Lawrence Lustig, an otolaryngology (that's ear, nose and throat) expert at Columbia University Medical Center, points out, we aren't on the verge of humans being turned into charging stations for artificial intelligence just yet.
"The amount of energy generated by the endocochlear potential is enough to drive the hair cells of the inner ear, but not really enough to do anything useful at present," Lustig told Mic. "Theoretically, as our machines become more and more efficient, requiring less power, the ear may be able to drive some manmade processes, but not yet."
The idea of using the body to harvest energy isn't as sinister as it sounds, and the core concept, using our bodies to power other things, isn't a new technology. As Robin Wylie of Ars Technica wrote on Sunday, the body is a more efficient power plant than you might think.
Enter Human Energy Harvesting.
Sweat as fuel: In 2014, Patrick Mercier, an assistant professor of electrical and computer engineering at the University of California, San Diego, and a team of researchers published in the Journal of Materials Chemistry A a paper investigating the potential of a wearable biofuel cell printed onto fabric, like a headband or wristband, to use sweat as fuel to generate electrical energy.
"The human body generates a tremendous amount of energy. Tapping even a small portion of this energy could allow us to power many wearable and implantable devices," Mercier told Mic. "However, we need to come up with smaller, more efficient, and more anatomically compatible energy harvesting devices before bio-energy harvesting becomes a more feasible energy source. In addition, many sources of energy in the body are transient. We thus need better ways to harvest and store this energy for later use."
"The human body generates a tremendous amount of energy. Tapping even a small portion of this energy could allow us to power many wearable and implantable devices."
If Mercier's research gleans energy from the effects of movement, piezoelectricty is what's generated when you convert not the sweat, but the kinetic energy or mechanical stress — turning a crank, for instance — into usable power. Of course, making storable energy from physical motion isn't state of the art or even expensive technology. And researchers have found ways to use a simple technology to inspire larger projects.
Charging your phone with every step: In 2008, Canadian researcher Dr. Max Donelan created a knee brace able to harness the "negative work," or kinetic energy created by your walking stride, to generate 5 watts of electricity. While that doesn't sound like much, according to Physics World, that's enough to power several mobile phones — or even an electric artificial limb.
"Further in the future," Donelan says in a video from Simon Frasier University, "you could take the same basic principles, the same ideas of harvesting from a body joint, and doing this generative braking, and apply it to a fully implantable device that could be implanted underneath the skin and be used to charge, for example, implanted drug pumps, or implanted neuroprostheses."
What's next: Right now, all research points to a long road to human energy harvesting as a common and feasible means of powering our devices. But in most cases, there's a lot of proof of concept to offer scientists and doctors hope. The technology gets more advanced with every new study. And eventually, a Sunday afternoon bike ride might replace that drawer full of chargers and power cords.
"A device could be implanted underneath the skin and be used to charge, for example, implanted drug pumps."
"If researchers can figure out how to increase the average amount of extractable power over time and find ways to efficiently capture and store this energy in an anatomically compatible fashion, it may be possible to see such energy harvesters powering devices like wearable sensors," Mercier told Mic.
"Developing new wearable sensors that are autonomously powered by wearable energy harvesters, like we are developing in my lab and in the Center for Wearable Sensors at UCSD, can potentially make the future of wearable technologies much more bright."
h/t Ars Technica