When Life Gives You Lemons

One of the things I’ve come to realize about the internet in general, and Facebook in particular, is that it is a breeding ground for just plain bad science. If you’re anything like me, you’ll run across something in your feed that is flashy and interesting… and just plain wrong. This morning was no exception, when I came across this video showing someone charging their smart phone using a phone charger and an ordinary lemon.

This is one of those wrong things that takes off like wildfire for several reasons. For starters, it ties into that subconscious anxiety most of us have about our phone’s running out of juice (pun intended). Then it hits on key nostalgic points, in this case memories of Mr. Wizard running a digital clock with potatoes.

Electrodes sticking into a potato, turning it into a battery

Potato power!

So although this whole notion of charging your phone with a lemon seems attractive and plausible, this is yet another case of someone producing a fake video in the hopes of making a new viral sensation (and yes I’m aware that I’m not helping by putting the video in my post). But how can it be fake? The phone is charging. Well, more about that in a minute. First let’s get into why it’s wrong.

The lemon (or potato) battery works because of a chemical reaction that occurs when two electrodes of different metals (one copper and one zinc) are inserted into something like a lemon. The chemical reaction is what puts a small electric charge in the wires. This is where the first problem arises. The video puts each of the charger’s prongs into a different half of the lemon. There is no way for electrons to flow between the electrodes in that case.

The second problem is that the adapter itself is designed to turn household power, which — depending on where you live — is either 110 or 220 volts of alternating current, into 5 volts of direct current. Without getting into too much detail, there are a bunch of electrical components inside the body of the charger that convert that electrical current. The small amount of electricity you get from a lemon battery would simply stop there.

So let’s say that you toss the wall wart to the side and do a little surgery on your charger cable. You connect the two charging wires up to a galvanized steel nail and a copper rod and stick them in a lemon. Then you connect the other end of your charger to the phone and… well, probably nothing. Again, a lemon battery produces at most a volt, which is a bit less than the 5 volts you’d need.. If you were clever enough with electronics you could wire up several lemons, but at that point you might as well just plug your phone in.

What’s Going on Here?

It’s hard to say. It could be a bit of camera trickery, but if I wanted to do this I would cram a battery-powered USB charger into an old phone charger body. That would allow me to charge the phone and with the outlet prongs stuck in a lemon it would look like the lemon was charging the phone.

So why fake it? For laughs, or for page views. As far as fake science Facebook goes this one is pretty tame. Nobody will get hurt doing this unless they manage to cut themselves while slicing a lemon. Trying it wouldn’t be any harm either… just make sure you clean your charger first so you can use the lemon later (Tom Collins anyone?).