You probably think you know how electricity is produced and transmitted. It’s made at a power plant of some kind, and then transmitted to homes and businesses by power lines either above or below the ground (about 18% of U.S. lines are underground, according to the Energy Information Agency).
But that’s far from being the only way electricity is produced. In fact, your body produces electricity all the time. It’s electricity that causes muscles to contract, meaning it’s electricity that makes your heart beat. And human electricity is better documented nowhere than in the brain, which contains about a hundred billion biological “wires.”
It’s that fact that led Maddie Stone of technology blog Gizmodo to pose an intriguing question for an Aug. 12 article: Could your brain charge an iPhone?
Understanding Electricity
In order to answer this question, it’s necessary to understand a little more about electricity itself. Electricity is a natural phenomenon that simply refers to electric charges moving across a gradient.
In a power system like the one described above, those power lines move electrons around. But in the brain, membranes produce ions with roughly the same effect. When power lines carry electricity from a nuclear reactor or coal-fired power plant to your house, can you plug in your phone and charge it. When the neurons in the brain fire, they power the body.
The trick about electricity is that just because it exists somewhere doesn’t mean we know how to harness it.
That’s the case with the brain; although we can roughly measure the electrical activity there, we don’t have any way of harnessing it for external use. That didn’t stop Stone, however, from calculating how the electrical energy in the brain would stack up if there were some way to simply plug your charging cord into your forehead and give your smartphone’s battery a boost.
Your Brain vs. an Outlet
You can check out the full calculations and brush up on your high-school physics via Stone’s article, but here’s a basic breakdown:
There are about 80 billion neurons in the brain, and it’s currently thought that about 800 million of them might be firing at any one time. Each time one fires, it produces about a nanoamp of electrical current. That adds up to some .085 Watts of power output for 800 million neurons. That’s about what it takes to power an LED light bulb.
An iPhone 5C battery holds a charge of approximately 5.74 Watt hours. So dividing that by .085 Watts comes up with an answer of 68.33 hours.
Of course, as Stone notes, you wouldn’t want to divert all that energy into charging your phone even if you could, since that would deprive the body of the power it needs to function. So perhaps it’s best to stick to your local electric company when it comes to your charging needs.