Presented by:
Kulkarni Makrand
Kumar Chandrahas

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INTRODUCTION
Let's face it, energy is expensive gas, electricity, whatever. So why pay to cook your food? The challenge we gave was to cook food, without spending any money at all. No electricity, no gas, nothing. And, there are no negative side effects on the environment, resulting from our hot dog. What we came up with was...the parabola. So by using the properties of parabolas, we're going to cook a hot dog. Essentially, we're using math to cook hot dogs
The sun sustains life on earth; it is available to everyone daily. There is no cost for solar radiation. Using parabolic, box, or panel cookers means no gas or electricity costs. They are easy to maintain and just as easy to build. With a little planning and some basic mathematical calculations, anyone can own their own solar cooker.
But what are the advantages to using a solar cooker? Besides the economic savings, solar cooking helps in the fight against global warming and deforestation. By using the sun's rays to cook meals, firewood is saved and in many remote areas time is used more usefully than for gathering the necessary firewood needed for wood burning stoves.
In the remote areas of the world a solar cooker can be used to distill drinking water and feed villages. Many people in the world must survive on polluted surface water that is difficult for them to decontaminate. Solar cookers offer an easy solution to this problem.
Often times, it is necessary to collect wood to build large fires in order to purify water. Solar cookers distill water cheaply by using the sun's rays to heat a pot of water. They can be a cost effective solution for those that may otherwise have no resource to purify their drinking water. Solar cookers are also easily transported to remote locations. In many parts of the world they can be easily built using local materials. There are several organizations and programs worldwide that promote the construction of these solar cookers.
Many ask, how effective are solar cookers? The effectiveness of a solar cooker can vary depending on what materials are used, how well they are crafted, and what type of climate you live in. Cooking time with a parabolic cooker is similar to a conventional stove, and a box oven is similar to a conventional oven. Cooking may take longer is there are fog, clouds or shadow.
Using a solar oven to slow cook a meal means the food is cooked uniformly and doesn't burn no matter how long it is allowed to cook. Since dishes are allowed to blend and cook in their own juices, the food retains its nutrients. No vitamins or minerals are lost in the process. The only necessity is sunlight; even snowy climates can enjoy the advantages of solar cooking. Parabolic cookers require closer attention because they can reach much higher temperatures.
HISTORY OF SOLAR ENERGY USE:
The harnessing of solar energy began with the ancients. They were the first to begin using passive solar design in their homes and to use glass to trap solar heat. The use of curved mirrors to concentrate the sun's rays was developed by the Aztecs, Greeks, Romans, and Chinese. The concept of "burning mirrors," for weapons, has been considered for millennia. It was through the Greeks geometric development that they discovered a parabolic surface held the ideal shape for these burning devices.
Awareness of the ability for glass to trap solar heat became increasingly important in the eighteenth century. It was during this century that
the first "hot box" was invented by Horace de Saussure. With the advances in science and technology during the Industrial Revolution, came the development of various devices designed to harness solar energy. Solar pumps, solar cookers, solar heat engines, and solar stills are just some of the inventions of this time.
Augustin Mouchot, a professor of mathematics at the Lyceé de Tours, was an important figure in this revolution. He was the first to develop a solar cooker; he was successful in finding a benefactor to fund his research. This led him to Africa where he invented a portable solar oven for the French troops.
Although these various solar inventions were never very successful on a large scale, they did aide in the advancement of a practical development of this revolutionary technology.
It was in the 1950's that solar cookers began to evolve into the products we see today. The United Nations and other agencies began solar cooker design studies. These studies found that when properly constructed, solar cookers not only cooked food thoroughly and nutritiously, but also were easy to build and use. Programs were created to introduce these designs to remote locations in the hope of aiding those in need.
CONSTRUCTION & FABRICATION PROCEDURE:
For the solar cooker the materials used are:
1. Two pieces of plywood, 1/2 inch thick, 2 feet wide and 4 feet long.
2. Two pieces of lumber, (2x4) 1 1/2 inch thick, 3 1/2 inch wide, and 8 feet long.
3. 16 wood screws, 2 inches long.
4. One stiff steel wire, 3 feet long.
5. 92 small nails or wooden pegs, about an inch long.
6. One plastic mirror, 1/8 inch thick, 2 feet wide, 6 feet long (although 5 1/2 feet long might work better).
7. A drill and a bit that matches the diameter of the 92 small nails or pegs. A larger bit (over 1 inch wide) is needed for the food hole.
Assembly the parts
The two sheets of plywood are placed together, one on top of the other. Using a tape measure and a carpenter's square, the points are mark off where the holes will be drilled for supporting the aluminium foil (the 92 small nails or pegs).