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Can I generate energy from CDs? How does it work?

i want to make a cd that generate energy , i saw a video on youtube , i'm asking if anyone knows if it works ? 

Kaustubh Katdare
Kaustubh Katdare • Feb 19, 2019

... some more information about what exactly you are trying to do will help. By CD are you referring to "Compact Disk"? How do you want to do it?

Im trying to use CDs as solar panels , and i saw those videos on youtube and i don't know if it's fake or it'll work 

https://www.youtube.com/watch?v=8l25cZ1wq-8

Yes i'm referring to campact disk

Kaustubh Katdare
Kaustubh Katdare • Feb 19, 2019

That video looks fake to me. 

The CD is irrelevant. It is just a support for the LEDs. If one sees carefully the resin body of the LED (an insulator) is all that contacts the CD. What one sees is the voltage at the terminals of the LEDs inseries.

Being a CEan (and anyway declared crazy for all of my 80 years by various people including for the last decade by my granddaughter) I just now took one LED, connected a voltmeter to the terminals and exposed the LED to the sun on my  11th floor office window. Bingo! It showed 1.37 volts DC and 0.05 in the dark.

So the CD has nothing to do with it. The LED silicon junction acts like a solar PV.

You live and learn.

I found an almost identical experiment on the net. Except that I used a red LED. Nothing new under the sun!

https://youtu.be/eYmvwRdnuLk

Kaustubh Katdare
Kaustubh Katdare • Feb 20, 2019

@Ramani Aswath - I'm curious - 1.37 Volts from a tiny LED looks impressive. I'm going to give this a try. 

In the mean time, let me tag @Harshad Italiya for his comments. 

PS: I thought the experiment was fake. ? 

The experiment claiming the CD produces the voltage is fake. 1.37 V is just the voltage of the junction. That does not mean that we can get meaningful current from it. It will not light up another LED inseries with it but kept in the dark. I shall try that out and revert.

Did that. Did not work even with two LEDs in the sun and one in the dark. The LED in the dark did not glow. Not much current flowed.

Lot of fun though.

Harshad Italiya
Harshad Italiya • Feb 20, 2019

1.37 V is just the voltage of the junction. That does not mean that we can get meaningful current from it.

Exactly ! There can be 1.37v but not significant current Power is combination of Voltage and Current so what Ramani Sir has observed is correct it's just the junction voltage which varies depending on Light only.

I can't be more thankfull for the help , i'm going to give this a try in my mini project.

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