Solar powered stove using 100% recycled materials

This is an exercise in recycling and alternative energy use. I used a discarded 62 inch satellite dish and used CD's to create this along with materials that I had laying around. Nothing was purchased for this project.

Step 1 Making the base/stand

I did not have the base, so I made one from 3" ABS plastic pipe inserted in the ground about 18". I then filled it with concrete and re-rod for stability.

Comments

[NikonDork]

Last summer, I made something similar - but different. My goal was a solar cooker, only instead of an old dish and CDs, I busted up a rather large wooden pallet for the 3x3's it was made with, built a crude frame and mounted a huge Fresnel lens from a 65" projection tv. However it turned out to be something more like lemonie's Death Ray idea - in the mid day summer sun I had it at about 2100-2200 degrees Fahrenheit at its most focused point. I tried cooking a hot dog under it and even with the food well away from the most focused point, it still turned into charcoal. So I switched gears and started melting pennies.

[sanjay_lim]

Simple alternative for expensive lens prepare sandwitch of plain glass on one side other side convex glass or glass dish fill gap with water , you can have bigger lens.

[Dr Qui]

I lol'd at this "So I switched gears and started melting pennies" I love when something you build turns out to work just way to well for what you want to use it for practically so it then a case of lets see what damage it can do.

I would love a Fresnel lens to play with, but in Ireland there is just not enough sun shine to validate the expense of lens.

You should try reflecting the focused light onto the bottom of a case iron pot or skillet with a mirror.  Check out greenpowerscience on youtube.

[SMarshall14]

try scotland its even colder, but just after its snowed there will be a bit of sunshine ,try then (Still to make one so not to sure).

[NikonDork]

Its too cold out now, but my future plans with this beast is to use it to power a solar oven to bake fresh bread.

[glorybe]

By chance was that a frozen hot dog? If you put a hot dog that is frozen in a microwave it turns to charcoal or an ash like substance.

[NikonDork]

It was not frozen.

[Shiftlock]

I don't know what kind of hot dogs or microwave you have, but I used to microwave frozen hot dogs all the time. I would par-cook about 100 of them them on a really hot BBQ grill to get a nice dark exterior, then freeze them so I could enjoy a hot dog that tasted like it was from the grill all winter long. Right out of the freezer and into the microwave for 90 seconds, and they were perfect.

A hot dog is just meat. People microwave frozen meat all the time. It doesn't mysteriously flash into ashy charcoal. There's no reason why it should, unless you're talking about microwaving for a very long time - well past the point of it being very hot. In that case, almost anything with fat in it will turn to charcoal, given enough time, and it doesn't have to be frozen before hand.

[timmyghudson]

Shiftlock

You are a genius! I love you man.

[glorybe]

If you put the microwave on thaw you can usually cook a frozen dog. But if you put it on high with continuous high energy it will turn into a disaster. It will not have any moisture in it at all and will crush into a powder with ease. Try it.

[Shiftlock]

I'm telling you, I used to do this all the time. Frozen dogs wrapped in a paper towel right into the micro. I must have done it 100 times. Maybe wrtapping it in a paper towel makes a difference, or maybe the brand of hot dog makes a difference, I don't know. They were, perhaps, a little dryer and slightly more "rubbery" than non-frozen hot dogs cooked in the microwave, but I never had one "crush into powder" on me.

I'll take your word that it can happen under the right circumstances, though. Do you have a theory for exactly what's happening when they turn into "powder"?

[NikonDork]

It was not frozen, it was only cold.

[thetech101]

Where can I find a large fresnel lens? I don't need one that large and I would prefer to spend less than 50 dollars.

[NikonDork]

Keep on the look out for when someone throws out a large projection tv. The front screen is a huge fresnel lens. Thats where I got mine.

[woodbike]

 Try a company that makes the lenses for Stop Lights, most of them are
Fresnel lenses,  fixed to keep people from jumping lights, At least in Chicago
ILLINOIS.

[desertdog]

Thanks.

[NikonDork]

search craigslist constantly in the free section and wait till someones getting rid of a projection tv. free lens dude.

[thetech101]

Thanks. I have been for a while, but so far, nothing.

[Houdinipeter]

thats just like http://googleblog.blogspot.com/2009/04/will-it-lens.html

[thetech101]

Yikes, that looks menacing. I'll have to try it when I build my solar hot water heater.

[desertdog]

Wow, that is some serious temperatures. I wanted something more in the usable temp. range. But it gives me thought for another project.

[NikonDork]

Serious temperatures is an understatement! The day I built this thing, my buddy and I were having a blast for hours melting various objects, boiling water in a small Pyrex measuring cup in mere seconds, and making instant fire. Throughout the afternoon, as the sun moved across the horizon, we had to keep manually adjusting its angle to get the best efficiency out of the lens. By the end of the day we had the frame angled so low, that when we walked away from it for a minute or two, it started melting the black-top in my driveway! Word of caution: be very aware where your putting yourself in relation to the focused beam. This thing can give you a serious burn almost instantly.

[desertdog]

How far from the lens is the focal point?

[NikonDork]

I don't remember exactly, but in the midday sun it was about 15-20 inches from the lens. You'll definitely know when you hit the sweet spot. Take a scrap piece of wood and carefully hold it in front of the lens and "focus" the beam by moving the wood closer until it brings the beam down to the size of a dime. In a second or two it should be hot enough to set it alight. Focused beam diameters will vary with the size of your lens and time of day.

[build a BOOM]

Several days ago I took a dollar store frensel lense 8" by 11" and was able to melt a new (after 1982) zink copper plate type penny.

[desertdog]

I would like to find a deal like that at a dollar store. What store chain did you buy that from. I have some real ideas for that. Let me know.

[build a BOOM]

I dont remember, but it was 1 dollar and labeled as "full page magnifier" and came in a sort of envelope. I would look in the school supplies section near the paper and possibly other magnifying glasses.

[desertdog]

Thanks, I will take a look around for that in my wanderings.

[Dr Qui]

Nice idea,

Another reasonably cheep way to do this is to use the foil coated Mylar sheet that is used in hydroponics to reflect light. you can cut pieces from a sheet and use contact glue to apply them to each segment of  the dish. the sheet can be heat shrunk slightly to remove the worst of any ripples.  Mylar would allow you to catch more of the available light and the focus is slightly better as it follows the parabolic shape of the dish perfectly.

I would love to do more solar experiments, but alas the sun does not shine as much as I would like here in Ireland.

[jj.inc]

You could probably set it up as a solar tracking one, but you might need to get something for E-W rotation.

[thepelton]

If I still had some, this would be a good use for some of those old AOL trial run disks. Something that just occurred to me. What if you put the CD disks in a saucer sled? It isn't as big, but would get you some light concentrated for your stove.

[aspiremkd]

watch this video
http://www.youtube.com/watch?v=z0_nuvPKIi8&feature=player_embedded

[(YOUR N]

SOSIGE

[(YOUR N]

SOSIGE

[(YOUR N]

SOSIGE

[arpoky]

I think if you get a ton of old Hard Drive Disks, this could work better. Hard Drive Disks are metal and won't melt like a CD/DVD on a hot day, and they are also more reflective, but be aware that they might make this project weigh a few more pounds.

[desertdog]

I did give that some thought initially. The CD's were easier to get in large quantities, though.

[arpoky]

Try using the electroplating method and plate them with copper, it works great.

[EduGreat]

WOW! this is great I have a smaller (36inch?) fiberglass dish and have been trying to think of low/no cost reflectors, hadn't thought of the CDs - What do you cook in the basket? If the CDs don't produce enough heat for my smaller dish I may have to go with buying a pack of stick on mirrors from Lakeshore (lakeshorelearning.com item #FF817 $10.95 for 20 8.5x11 sheets) Thanks again

[Treknology]

If the dish you're using is solid rather than mesh, why not just use "chrome" paint?