# How to Power an LED with Lemons

If life gives you lemons… make batteries! Let there be light with these simple steps.

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### Up next in How to Do Fun Tech & Science Projects (52 videos)

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#### You Will Need

• A knife
• 4 lemons
• 4 pieces of copper wire
• 4 galvanized nails
• Voltmeter
• 5 jumper wires
• An LED light
• Four U.S. pennies minted before 1982 or four Canadian pennies from before 2001 (optional)

## Steps

1. Step 1

#### Soften the lemon

Roll a lemon around on a table to soften up the inside without breaking the skin. If it's too firm, it could reduce the battery's charge.

2. Step 2

#### Put the copper in

Use the knife to cut a slit in one lemon and insert the wire so a bit of it sticks out. This is your battery's positive terminal.

3. If you have a U.S. penny minted before 1982, or a Canadian penny from before 2001, you can also use those.

4. Step 3

#### Put the nail in

To make the negative terminal, push the nail into the lemon about 2 inches from the penny. Leave a little of the nail exposed above the skin. Make sure the copper and nail are not touching, or it will cause a short.

5. Step 4

#### Measure the current

Turn on the voltmeter. Touch the positive lead to the penny, and the negative lead to the nail. If the meter indicates that the lemon is creating a little less than one volt or more, you've successfully made a battery.

6. You'll know you have the leads connected backwards if the voltmeter registers a negative number.

7. Step 5

#### Make more batteries

Make three more lemon batteries. A single lemon won't produce enough electricity to light the bulb.

8. Test each battery with the voltmeter to make sure you have four working batteries.

9. Step 6

#### Connect the batteries

Clip the first jumper wire to the nail in the first battery, then run the second wire from the penny of the first lemon to the nail in the second lemon. Then connect the penny in the second lemon to the nail in the third, and the penny in the third to the nail in the fourth.

10. Step 7

#### Light the bulb

Light the LED by connecting the first jumper wire from the nail to the negative connection on the LED. The negative connection is the wire nearest the flat spot at the base of the light. Then clip a jumper wire from the penny of the last lemon in your chain to the positive connection on the LED and presto! Lemon-powered light!

11. Did you know? The world's largest battery energy storage system is in Fairbanks, Alaska.