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Sunday, October 29, 2006

Ping-Pong CD Solar Concentrator

Look at the title of this post, understood anything? The last two words are okay but got any guess whats that pingy pongy stuff. Well, let your inner curious feeling read the rest of the post to satisfy itself.

Ping-Pong CD Concentrator is an idea that flashed into my mind when I saw the shiny side of a pile of useless CDs & DVDs lying on my desktop. The ping-pong element comes from a common plastic ping pong ball thats used to play table tennis. I was a table tennis player in school.
So, imagine a CD placed on a ping pong ball with shiny side up. Ball fits into the hole in centre of CD and if you fix the ball there, what you get is a kind of rotating mirror which can rotate 2 sides either right-left or front-back. Lets visualise it;

This is what it should look like. Attach the ball to the CD using adhesive.

This rotating type of mirror-like arrangement is the precursor to our Solar Concentrator. Quite intuitively, you can see that this CD can direct light falling on it to any side wherever it rotates. This is the basic concept that is used in Heliostats (Large Sun Tracking mirrors).

Now suppose you collect some waste CDs lying around and buy an equal number of ping pong balls (very cheap) and then build individual units like described above. Arrange them on the floor and fix them there using plasticine or clay (kids play with) in such a way that all of them point toward a common centre. The image below will make things clear;

I made a demo project as you can see on the right. All the individual units are concentrating sunlight on a circular point on a wall (not in picture).

This is a nifty little idea to concentrate sunlight easily. Equate this with what is shown below;
it is a power tower with hundreds of heliostats concentrating sunlight on the top of a tower.

Like this idea? Tell us! Your Suggestions invited. More updates to this will continue.
Start collecting waste CDs now!
C ya


sinclair said...

Mridal, I really like this idea! I will get some of my pupils to try this later in November when we look at alternative energy.

kavan said...

your ideas are just great....

Mridul Kashatria said...

Thanks kavan,
I miss you guys and time we spent at Anna University!

chalacuna said...

Harnessing the enrgy from the sun is the best alternative and renewable source of energy. The sun is totally and 100% environmentally friendly.

The only drawback to solar paower is the initial investment which is at present is not practical econoomically to many consumers.

If advanced manufacturing techniques are developed to produce cheaper and more effecient solar panels, time will come most houses will be having roofs made of solar panels and that would help a lot in making a better and pollution free world.

Related Sites:

Alternative Fuels
Automotive World
Hybrid Cars

Anonymous said...

i know but what can the so call splar thing can do

Daniel said...

I think it would be interesting to explore homemade and cheap methods to harness the energy that the CD's are concentrating. Even if the application was tiny (say, power a small LED, to start), it would be an excellent demonstration of "home" solar power potential.

serenityjun said...

Great idea, but i am trying to figure out how the device is going to track the sun for the whole day?

Eric said...

Mridul! We haven't talked for so long, and I decided to come back to read your energy blog.

I like your ideas, and I think this is a great way of applying the 2nd R in the 3-Rs: Reduse Reuse Recycle. Keep the ideas flowing, I think you'll become a great inventor!

Anonymous said...

While I agree that we need to harness the power of the sun, solar panels are one of the most harmful things produced on the planet. The environmental damage cause by the construction of the panels FAR EXCEEDS their value as a non-polluting source of energy.

It's time to get real when evaluating 'green' technologies.

As far as the CD/ping-pong thing, seems pretty clever to me. I think the best way to use them is to see how many it takes to boil water when all are concentrated on a small glass. If you can do it, you can then scale it up for home use, using a boiler (thermal/steam) to power your home.

cga_cj [at] hotmail [dot] com

Logan Longbourne said...

If you try this, PLEASE be careful. Enthusiasts who built solar concentrators in the early 80's will show you the burn marks to prove it. Those who wore protective glasses, that is...

DaveMustoe said...

Does anyone know what energy is used in the process of manurfacturing a ping pong ball? I need it for a science project!!!! Please help?