Picture of fruit clock
this instructable will show you what fun you can have with fruit and time!!!
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Step 1: Supplies

Picture of supplies
in this experiment you will need

two oranges (any citrus fruit will do but oranges are cooler)
two pennies
two large paper clips
three pieces of copper wire (about 6-8")
a battery operated digital alarm clock
scissors and/or knife

Step 2: Preparation and beginning

Picture of preparation and beginning
first, attach one copper wire to one penny, and another to a paper-clip.
now attach a paper-clip to one end of the last wire and a penny to the other end.

roll and squeeze the oranges to loosen up the pulp
now make two incisions on each fruit, (about 1.5 inches or 4 centimeters apart) and put the penny wire in one hole
then on the other fruit, insert the paper-clip wire. and then insert the dual wire's individual pieces into their opposite fruit (paper-clip to penny and vise versa)

Step 3: Get attached

Picture of get attached
now there should be a wire sticking out of each fruit and one wire connecting the two fruit.

stick the wires into their appropriate places on the battery terminal of the clock and it should start working!

the energy from the oranges should last up to a week!

Step 4: Why this works

Picture of why this works
There's a chemical reaction between the steel in the paper clip and the lemon juice. There's also a chemical reaction between the copper in the penny and the lemon juice. These two chemical reactions push electrons through the wires.

Because the two metals are different, the electrons get pushed harder in one direction than the other. If the metals were the same, the push would be equal and no electrons would flow. The electrons flow in one direction around in a circle and then come back to the lemon battery. While they flow through the clock, they make it work. This flow is called electric current.

Step 5: Thanks

thanks for reading my instructable! i hope you have a blast and it as works well for you as it did for me.

special thanks to virtuallibrary.stao.ca and keetsa.com for the photos used in the intro and the "why this works" sections

Go Green and help our planet!
ADYAA3 months ago

instead of pennies what can we use

What happens to the orange after a week? Would you be able to eat it or compost it?

can i use something other than battery clock...some kind of bulb something that does not require battery....how much voltage is obtained through this circuit
and can i use just pins instead of coin?
Kashii663 years ago
nice work......
belgvr6 years ago
how long does it lasts?
shiboohi (author)  belgvr6 years ago
if the conditions are right it should last for up to about a week :) have a great day, Shiboohi
lolz in an "emergency" I could charge my ipod via oranges, am I rite?
shiboohi (author)  lgeroso4 years ago
as awesome as that would be i'm afraid its not quite powerful enough to charge something like an mp3
i guess it could if you have a box of oranges (lol?) and all of them are wired up corrrecty...... its interesting :-]
I Like This But How Long It will Be running ?
louwhopley4 years ago
Looks cool! I figure that the chemical reactions make the fruit go bad or make it last only a week... but wouldn't it work quite well to hook it up to citrus fruit still growing on a tree?
shiboohi (author)  louwhopley4 years ago
yes, it lasts roughly 5-7 days. Being that i've never tried to hook it up to a citrus tree i would not be able to give you an accurate answer. but i would love to hear your results! this instructable is the bare minimum, but i encourage all of you to take the idea and run with it!
Arano shiboohi4 years ago
i am not shure, but doing this on a growing fruit i think there a 2 possible things that might happen: 1. the fruit will die 2. the tree might die... both because of the copper is very bad for plants... (if you want to kill a tree: hammer a copper nail in)
yes U R Right.thanks For Information.
Afif_D3 years ago
can you tell me wats the emf of this cell you just made?
hopporto4 years ago
lol i had the exact same kit shown in the pic.
I once had a potato clock. Until it rotted.
its cooll..
Beduk4 years ago
cool.that loooks amazing!!!good job!!:)
dombeef4 years ago
What is the one on the first page, Where can you buy that clock?
ynze dombeef4 years ago
Do a google-search on "fruit-clock.jpg". You'll find a dozen websites that sell it.
dombeef ynze4 years ago
Wow! I guess that they have a capacitor and run on really low energy, i had a clock that would run off the sun that i made, i am trying now to make it run off plain water
tim132115 years ago
if you where to connect the wires to citrus juice would that do the same thing?
e.i. store bought orange juice?
Arano tim132114 years ago
it would work with vinegar ;) anything acidic should work
shiboohi (author)  tim132115 years ago
 i'm not sure. i have never tried. it might be worth a try
solarmatrix6 years ago
The 9 VOLT battery clip on the mains powered clock is for backup in the event of a power failure and will not display the time in that state, it will only keep the time for when the mains power returns. Show me a picture of the project working where your hand isn't covering the mains power cable supplying power to the clock! (step/pic 3) Make it, don't fake it! (whats the point in that?) your two cell orange battery would not have the required voltage or current to run the led clock even if it did display the time without mains connected. You would have to take out the transformer inside and bypass the rectification circuit You would still require more than the 2 volts at microamps you would get using your orange battery!? Now on a more positive note, I suggest you try an L.C.D. clock or old wristwatch. It would work at the above stated voltage/current. you can also use just one lemon/orange with a few copper/zinc probes in series for the required voltage and more surface area for more current to make it work & last. Zinc coated nails/copper pipe work better than a paperclip/copper penny. See also "supercharged lemon" instructable it clearly works well (tried) and would actually run an L.C.D. clock/ watch (as pictured in intro) for well over a week. I estimate a month or more. thumbs up for author "s8" Good try, shiboohi
shiboohi (author)  solarmatrix6 years ago
yes you are right it is for a backup, and it does save it, but this is all just to prove the principle. rest assured that this device does work. and about the zinc and copper pipe this was created to be simple and inexpensive, a penny and a paper clip, about 3 cents. how much would it cost to get a box of zinc coated nails and a copper pipe? and i did not fake this. thanks for trying though ;) P.S. don't be the guy who goes around instructables website trying to prove everyone wrong... nobody likes that. have a great day, ;) Shiboohi
Most people have a few nails and access to a bit of copper (scrap metal merchant?) I got a piece for free. How much is a box of paper clips and two pennies? more than 3 cents i suspect. I give credit where its due (s8 supercharged lemon) and i agree that the project would work with an L.C.D. clock as pictured in your intro but NOT the way you have shown and i described why. I have 22 years exp in the electronics / alternative energy industry and i put in some constructive feedback I find it funny that you take offence to that. You too have a good day ........solarMatrix.
shiboohi (author)  solarmatrix6 years ago
well i am sorry you don't find this living up to your 22 years of experience standards. but this is, after all, for beginners. why would you go looking for something on the internet, that you would already know how to make?
I was looking at the other more advanced alternative energy ideas that are posted on this site (some are actually unique!) when i spotted your intro picture which i still think is a good concept which is why i took the time to put in some constructive input as well.
I might even make a solar powered led clock adaped from your post. cheers!
shiboohi (author) 6 years ago
how's this, better huh? haha thanks for the tip!