It’s a standard children’s science experiment: insert a nail and a penny right into a potato and also use the slight little bit of voltage created to strength a tiny clock or some other low-power gadget. Those of us of a specific age might remember MacGyver pulling turn off a similar trick. Once I to be a kid, i would put a nail and also a penny in one apple and also rub a headphone plug along them come make static noises.

You are watching: How long does a potato battery last

Recently, someone mutual an short article in one of my prepping teams claiming the boiled potatoes can power a light for 40 days. The write-up even insurance claims that this could have assisted Texans influenced by the recent winter storm blackout.

*

So we tested it, and no, it’s no true.

Summary:

The scientific research behind utilizing a potato or other develop as a battery is as old as batteries themselves.The potato doesn’t actually produce any type of electricity. Rather, that the metals inserted into the potato slowly dissolving and releasing electrons.A solitary potato battery only produces about fifty percent a volt. It would certainly take several potatoes linked together come power even a solitary LED, much less whole light bulb.The strength output the a potato battery deserve to increase together it rots, yet boiling a potato provides only a short-lived boost.

The science behind potato batteries

Alessandro Volta made the an initial battery in 1800 by placing a piece of zinc and a piece of copper right into a brine. The zinc and copper pieces served as electrodes and the brine acted as an electrolyte. An earlier experiment by Luigi Galvani prove that placing pieces that copper and zinc on a frog leg caused it to contract. In that case, the frog leg to be the electrolyte. (Galvani’s experiments motivated Mary Shelley to write Frankenstein.) This sort of battery is today recognized as a voltaic or galvanic cell.

The potato doesn’t actually provide any electrical energy itself, it simply serves together the conductive medium. The metals really slowly dissolve in the conductive medium, giving off free electrons that seek a more attractive, steady home. In the usual experiments, the zinc dissolving and also its electrons flowing to the copper. Various other metals deserve to be used, but both need to be of various types.

In home experiments, the most common materials room nails and also pennies. Nails are commonly galvanized, or covered in zinc, to save them indigenous rusting, and also pennies are straightforward source that copper. So you can stick a nail and a coin in a potato or lemon and also get a tiny amount of voltage. Eventually, the battery dies because either the zinc is depleted or the electrolyte is supplied up.

There are also low-power clocks you deserve to buy for youngsters that have the right to be it is provided by these homemade batteries.

The claim about boiled potatoes

In 2011, Israeli researchers made some truly incredible claims about potatoes. They said that by cook a potato because that eight minutes, slicing it, and also then inserting every slice between copper and zinc plates, they might make a battery enough to strength LED bulbs and also light up a room.

The ide behind cook the potatoes renders some sense. The scientists claimed that softening the inner potato lessened the resistance and let the electrons flow an ext freely. Together for the concept of sandwiching the potato slices in between metals, that’s nothing new: Volta walk the exact same thing in the 19th century, except he used file soaked in salt water instead of potatoes. That type of electrolyte sandwich battery is referred to as a voltaic pile.

It’s ten year later and people clearly aren’t jamming irradiate bulbs right into potatoes, for this reason what happened? In a BBC interview, the scientists declared that the was government red tape and also rules about not wasting food gaining in the means of powering the human being with potatoes.

The electric potato acid test

I recently had some electric work done, so i had whatever I essential to check this in a scrap pile: copper wire, nails, and also a light pear socket. Plus, I have actually a bag the potatoes, a multimeter, hookup wire, and also alligator clips.

I started out by sticking a nail and also a little bit of copper wire into opposite ends of the potato (It’s necessary that the electrodes nothing touch). Ns then measure up the voltage with a multimeter. I repetitively read around 0.46 volts — not even half a volt.

*

I wired increase the light bulb socket, screwed in a LED irradiate bulb, and connected it to mine potato battery. Nothing. I used my multimeter come verify that the 0.46 volts were getting to the light pear socket and they were.

I traction a few less power-hungry parts out of my son’s Snap Circuit’s electronics kit: a little lamp and an LED. The potato it is provided neither.

I resolved up an additional piece of wire so ns could affix two potato together. Combined, the two potatoes provided me 0.89 volts. For this reason again, not even whole volt.

*

Even with twin the power, nothing I connected to my potato battery worked. I determined to boil the potatoes and also see if I might increase the juice.

I boiled the two potatoes for eight minutes and also then placed them in an ice-water bathtub so they’d it is in cool enough to touch. Once cool, ns took one and also inserted the wire and nail.

I measure up 0.5 volts! A bump, yet not lot of one. I chose to affix two potatoes and also see if I might get a complete volt.

See more: What Are The Parts Of A Chemical Equation ? What Are Parts Of A Chemical Equation

*

But a funny thing happened. By the time I hooked the 2 potatoes back up, ns measured 0.9 volts from the two. Ns measured every one, and again ns was reading about 0.45 volts. Boil the potatoes had temporarily raised the voltage, however it dropped ago down again.