Intro: Multi-Parabolic Solar Thermal Cooker
All around the world, there are thousands of families without proper cooking systems. Children spend entire days to look for firewood, and they are kept from a proper education. These firewood cooking systems, in addition, cause premature deaths in households because of the constant carbon monoxide emissions into the air. The firewood stoves are destructive to the human body and to the environment.
The sun is a powerful source of energy, heating up the Earth from 92,960,000 miles away. Our solution is to use that power and energy to cook food efficiently and safely, both for us and the environment. Methods like solar panels do achieve that goal, but are very expensive and are not immediately accessible. What we are making is something that can be made cheaply, safely, and quickly.
A solar thermal cooker is an ideal choice for sunny areas. It has the same capabilities as a firewood system, and if made just right, can be even more efficient.
DISCLAIMER: This solar thermal cooker is not ideal and is made with the most convenient materials we were able to acquire. If you are able to get better materials, you can easily make this solar thermal cooker more powerful and more efficient.
Step 1: Build Materials
What we used were the most convenient materials we were able to acquire.
- Parabolic Dishes (Snow Disk, Old/Unused Satellite Dish)
- Reflective Material (Mylar, Aluminum Foil, Reflective Tape, Mirrors)
- Duct Tape, because it fixes everything.
- Various 1 1/2" PVC pipes and elbows (White would be the best color since it does not absorb the heat from the cooker)
- Frying pan, for the cooking.
- Bacon. We chose to cook bacon because we like bacon. Bacon.
- Adhesive, for the Aluminum foil, since the food wrapping does not regularly have adhesive on its backside.
- Windex, to make the reflective material more shiny.
- Hands. They are quite necessary.
- Sharp Objects, like box cutters and scissors.
Step 2: Take Precautions
Before we start building, we NEED to tell you: BE CAREFUL.
You are working directly with the sun's blinding light and heat, and if you are not careful, you will hurt someone or yourself. That is the point of having goggles or sunglasses. Do not aim the light at anyone around you, just at the pan. If you are holding or transporting the mirror or reflective dish, face it away from the sun and be sure you do not hurt anyone.
If you are not careful, this WILL HURT YOU. You will have an immense amount of power in your hands, so be responsible with your building, because
"With great power there must also comes great responsibility." -FDR
Listen to Franklin D. Roosevelt, but if you are more of a comic book guy than a history buff, listen to Uncle Ben.
"With great power there must also come great responsibility." -Uncle Ben, Amazing Fantasy #15
Step 3: Get Parabolic Dish and Get Dat Dish Reflective
NOTE: If your parabolic dishes have bumps, like our snow sled did, sand it flat. Those bumps will effect the efficiency of the dish.
Use your reflective material (Mylar is recommended) and carefully lay it across the entire parabolic object to make the object reflective.
Because these objects are parabolic, smaller slices of reflective material would work best. It would cause less bumps and bubbles in the reflective material and would be more efficient. (REFER TO PICTURE 1)
We recommend cutting the material into triangular pieces and applying it in a clockwise manner.
Step 4: Riot Pls Buff. Make Shine OP
We want the parabolic dish to be reflective as possible. In order to do this there are many different steps that we need to take. Naturally your dish will have many bubbles and creases as a result of taping the reflective material down. This is a problem because you'll have far more trouble with focusing your light.
In order to fix this, take your box cutter and make small incisions in the creased and bubbly areas. After you do that, push the air out and remove the bubble.
After you make the dish as smooth as possible, begin the shining process. Get Windex and spray it all over the dish, then begin BUFFING UP THAT SHINE.
Step 5: Get Dat Other Dish and Make It Reflective
You need to repeat step 2 and 3 for this dish: Get the dish reflective and buff it up.
Continue being very careful laying down the reflective material. Bubbles are bad. Flatness is good.
Step 6: Test Your Newly Reflective Dishes
Now that your dishes are reflective, you need to make sure they work. If they don't reflect at the proper place (a satellite dish should be focused, and a snow sled should be broad), you need to fix something. If you can't fix it, use the error to your advantage. make your error awesome!
Step 7: Prepare Your Base
Use the PVC and elbows to assemble the base together.
- Make sure you have a square shape base, because circles are impossible...
- You need a variety of elbows and PVC sizes to make this work, but since PVC is not expensive, this shouldn't be that hard.
- Make sure you have a counter-balance. You do not want the wind to carry the project away or destabilize it.
- Be sure your base can hold up a pan at least a foot or two in the air. You want the two reflective parabolic objects to hit the bottom and top of the pan, so it needs to be held above the ground
- It needs to be weighted so it is not carried away. So it would be a good idea to get sandbags or make some.
Step 8: Add the Parabolic Objects to the PVC Base
The base will be what keeps the cooker in place.
When you add the parabolic dishes, make sure that they are facing the sun and reflecting at the pan at the most efficient angle possible.
We placed a dish on the bottom and we duct taped the other dish to a PVC pole behind the frying pan. They were angled at the pan and were placed to give the most light (heat) to the frying pan.
Step 9: The More the Merrier
It would be great if you have more mirrors. We ended up acquiring two flat mirrors, angled them at the sun to reflect to the pan and used the heat they can produce.
You aren't looking for anything fancy lookin', just get the job done.
Step 10: Get Your Dishes Straight
I did mention it before, but this is important! If you do not calibrate your dishes, you will either miss the pan and blind someone or you will not be efficient in your reflecting.
And when I say "blind someone". I am not joking. You are bending the sun's light and energy to your advantage, and if you are not responsible with that, you will hurt someone for life.
Be careful. Make sure you yourself wear goggles or sunglasses too, If there is anyone working with you, give them goggles or sunglasses, because they are as vulnerable as you are.
Do not play with the mirrors. Do not try to aim the light at a distant person and especially not to someone closer in proximity to you. Light hurts, and if you have ever looked at the sun with your naked eye, you WILL know what I mean.
Step 11: Be Sure of Optimum Performance.
Let as little light out as possible.
Keep the energy in.
You cannot let the light and heat get away.
Place the base facing the sun.
The time is now.
Aim the cannons.
Save the women and children!
Cook the bacon.
Step 12: Cook Dat B-B-B-ACON
Or whatever you are going to cook.
You are done. Enjoy as you wish and be sure you cook your meal fully. The only people that like raw bacon are people that like raw bacon.