Could you use the human body to power tech like in "The Matrix"? While plugging in millions of individuals to act as "human batteries" is a little drastic, there are some less unethical ways to harvest electricity from the human body.
Here we explore five interesting examples of tech that already exist or are in development for just this purpose.
How much electricity does the human body produce?
The human body is an incredible piece of biology. It can do many impressive things, including producing small amounts of electricity.
According to sites like extremetech.com, the human body creates a surprising amount of it, even at rest.
"The average human, at rest, produces around 100 watts of power. This equates to around 2000 kcal of food energy, which is why your recommended daily intake of calories is around 2000 kcal."
Does the human body emit electricity?
The human body has various bodily functions that rely on the flow of charged ions like the muscles of your body and heart. However, one of the organs that has a lot of electrical activity in your brain.
This vital organ has somewhere in the region of a hundred billion electrically conductive biological wires, aka neurons.
How many BTU does a human give off?
For anyone who is a fan of "The Matrix", you'll probably have memorized that the figure is around 25,000 BTU. This sounds like a lot, and in fact, it is a little exaggerated.
The true figure, according to sites like filmschoolrejects.com, is somewhere in the order of 250 to 400 BTU.
"Morpheus says that the human body generates 25,000 BTUs, which as a unit of power is approximately ten horsepower or about 7.3 kilowatts. In reality, the human body produces between 250 and 400 BTUs of power, depending on its state of consciousness. In other words, when the body is asleep, it produces less." - filmschoolrejects.com.
What are some examples of tech that uses the human body as a power source?
So, without further ado, here are five interesting pieces of tech that have been developed, or are in development, that use the human body to generate electricity. This list is far from exhaustive and is in no particular order.
1. This team of researchers is harvesting energy from body heat
A South Korean team of researchers is looking at ways to use human body heat to generate power. The team at The Electronics and Telecommunications Research Institute (ETRI) South Korea hopes this could be revolutionary for wearable technologies.
They have created a lightweight, flexible thermoelectric generator that uses the temperature difference between a human and the surrounding air to generate electricity. The module is 5 cm in width and 11 cm in length and could be used as a form of a generator for another wearable tech in the future.
"When a patch-like structure is attached upon the thermoelectric device, a temperature difference occurs between the skin and the structure, imitating the sweat glands structure. This core technology is called "biomimetic heat sink." It increases the output of the thermoelectric module by five times that of conventional products, maximizing the energy efficiency." - Eureka Alert.
Initial tests of the device were able to generate 35 microwatts per square centimeter. This is around 1.5 times higher than other researchers working on similar tech in the U.S.
2. You can actually generate power from human sweat
Researchers at the Jacobs School of Engineering, The University of California, San Diego are working on a way of using human sweat to generate electricity. They have created a small temporary tattoo that incorporates enzymes that produce an electrical current from human sweat.
These enzymes strip electrons (oxidize) from lactate in sweat to produce small amounts of electricity whenever the wearer sweats (like during exercise). They produce enough electricity to power small electronics like LEDs and even Bluetooth radios.
"The biofuel cells generate 10 times more power per surface area than any existing wearable biofuel cells. The devices could be used to power a range of wearable devices.
The epidermal biofuel cells are a major breakthrough in the field which has been struggling with making the devices that are stretchable enough and powerful enough. Engineers from the University of California San Diego were able to achieve this breakthrough thanks to a combination of clever chemistry, advanced materials, and electronic interfaces. This allowed them to build a stretchable electronic foundation by using lithography and by using screen-printing to make 3D carbon nanotube-based cathode and anode arrays." - Jacobs School of Engineering.
3. This tech uses humans as biofuel cells
Back in 2011, a team of researchers at the Joseph Fourier University of Grenoble created an implantable piece of tech that can generate electricity from the human body. The biofuel cells draw power from substances that are freely available in the human body -- glucose and oxygen.
Each cell consists of two special electrodes that perform separate functions. The first oxidizes (strips electrons from) glucose. The other donates electrons (reduces) to molecules of oxygen and hydrogen.
When both electrodes are connected in a circuit, they produce a flow of electrons from one electrode to the other. This generates a handy electrical current that could be tapped to power wearable or other implanted tech (like pacemakers).
"Dr. Serge Cosnier and his team are the first ones who have been able to prove this concept by implanting a prototype cell into a living being and having it function. In 2010, an early model of the biocell was implanted in a lab rat where it stayed for 40 days, producing electricity all the while and having no visible side-effect on the rat’s health or behavior, a pretty promising success." - The Mary Sue.
4. This group of researchers has harvested electricity from the inner ear
A team of researchers in Massachusetts produced a device back in 2012 that can harvest power from your inner ear.
The ears of mammals contain tiny electric voltages called the endocochlear potential (EP). Found inside the cochlea, EP helps convert pressure waves into electrical impulses to send to the brain.
It is a very tiny electrical potential at around one-tenth of a volt, but this is still strong enough to power, theoretically, hearing aids and other aural implants.
Long thought unthinkable before the team created an "energy harvesting chip" the size of a thumbnail that can extract some of this electrical energy directly.
"They tested the chip in a guinea pig, implanting it into the animal’s inner ear where it generated enough electricity to power a radio transmitter. The minute electric power produced by the chip—about a nanowatt (a billionth of a watt)—is still about a million times too low to power an electronic implant." - Info Squad/YouTube.
5. This device generates electricity as you move
Converting human kinetic movement into energy is nothing new, but the nPowerPEG is a very innovative one. Developed almost a decade ago, it is a handheld tube-shaped device that clips onto a belt or backpack and generates electricity as the wearer moves around.
It incorporates a magnet weight, spring, and induction coil that all work in harmony to generate power. The device cannot produce enough electricity to power laptops or tablets, but it could have great potential in the future for powering another wearable tech or smaller electronics — like mobile phones.