Best Solar Oven: In my Engineering class, my teacher told us that we had to invent or modify something and post it on the Instructables web site. Tape two layers of plastic wrap across the opening you cut in the lid—one layer on the top and one layer on the bottom side of the lid. Teams of three or four will work best. You’ll find that the average cooking time for most meals is 2-3 hours on bright days. Teams should use books and other objects to prop the ovens at an angle that allows them to receive direct sunlight. A rear door makes this process a lot faster, and you lose less heat. Distribute Student Sheets and discuss the steps of the design process. The team whose oven completely cooks the food item in the shortest time wins. Photo by Joel Dufour. The first time, just set the oven into direct sunlight and watch the temperature climb. In other words, the solar oven is like a super greenhouse. Remind students that these are only the directions to build a basic solar oven and they are free to alter and expand upon these plans to make the most efficient solar oven possible. Close the lid of the solar oven and let the Sun heat it up for a few minutes more, just to melt the chocolate a bit. Line the inside of the box with aluminum foil, again gluing it down and making it as smooth as possible. After construction is complete, have all teams bring their oven to a designated area in the sun. Place a shallow cookie sheet on the floor of your solar oven functions as a drip pan. (Use a skewer, knitting needle, ruler, or whatever you have. A solar oven can burn you every bit as badly as a conventional oven. Place the pan in the preheated solar oven. Break graham crackers in half to make squares. A solar oven is a box that traps some of the Sun’s energy to make the air inside the box hotter than the air outside the box. Lid should have flaps so that the box can be closed tightly. You’ll be pulling the heated pot up and out of the oven, so get handles that facilitate this upward motion. Cooking can be accomplished as well on days when the clouds are high and thin, but it may slow things down a bit, and one would be wise to start a little earlier than usual. At maybe 3 to 5 feet (1 to 1.5 meters) across, it's essentially a sun-powered oven -- an enclosed box that heats up and seals in that heat. Years ago I had built a few diy solar ovens. Treat a solar oven with the same level of respect that you treat your conventional oven. Prop the flap open with a pencil. You just need to pick up a few tricks first. Play around and see how the temperature varies with different conditions (orientation to the sun, time in the sun, and so on). Set the solar oven in the direct sun. The instructor will determine when the food items are completely cooked. You also need a black, aluminum baking pot with a snug lid; everything that’s cooked will go into this pot, so this will limit your food options. They don't work at night or on cloudy days. Play around and see how the temperature varies with different conditions (orientation to the sun, time in the sun, and so on). Ideal cooking results when using a solar oven occur when the sun is bright and uninhibited or unimpeded by clouds, shadows etc. Push one end of the wire through the bottom of the milk container using the scissors to cut a hole if necessary. You can make an oven as big as you want, however, so that you’re not really limited. Cardboard box with attached lid. How would you redesign your oven base on the lessons you have learned? Solar ovens are not toy ovens, not by a long stretch. Allow teams a predetermined amount of time to construct their ovens (approximately 30 minutes should be sufficient.). You can’t rely on precision temperature control, so you have to stick with foods that aren’t fussy. The box cooker is a simple type of solar cooker. For example, a cake may not be a good idea. Line the inside of the milk container with aluminum foil. (The directions below are included in the Student Sheets.). Some people have cooked Thanksgiving turkeys in a solar oven, to very good effect. The object is to use the available materials to build the most efficient solar oven, able to cook a food item in the least amount of time. You may be able to cook corn on the cob. On most solar ovens you must lift off the glass top to check on or remove food. What you will need. Solar cookers use a couple of different methods to harness this heat. Using scissors and leaving the mouth of the container intact, cut away the side of the milk container with the handle. After working with your oven for a few weeks, you should be able to cook just as well as you do indoors. Climate Kids is produced by the Earth Science Communications Team at, NASA's Jet Propulsion Laboratory / California Institute of Technology. Test the stick you will use to prop the lid up. Gather all the materials and make copies of the Solar Oven Challenge Student Sheets. You can set a solar oven anywhere you want as long as it will get plenty of sunlight. You can cook half a dozen ears next to your barbecue, and they taste better than the boiled variety. Set the oven in the direct Sun on a sunny day when the outdoor temperature is at least 85 degrees Fahrenheit. Then, open the oven lid and place a piece of chocolate (about half the size of the graham cracker square) on top of each marshmallow. It will work with pretty much all your recipes. Note: Specific construction materials can vary as long as all teams have equal access to materials. Prop the flap open to reflect the light into the box. To do the actual cooking, you need a good drip pan to facilitate cooking and cleaning. I looked at three or four solar oven, and using their findings and ideas, I built the Ultimate SOLAR OVEN! This Solar O… Photo by: Debbie Wolfe Debbie Wolfe. What modifications from the basic design increased the efficiency of the oven? If you have three students per team, one will have the combined role of facilities engineer and developmental engineer (see role cards). The pot will get hotter than the temperature of the oven cavity itself (unlike a conventional oven), so be extra careful. To green up your life, you can build and cook with a solar oven. Introduce the challenge. (The directions below are included in the Student Sheets.) Place a marshmallow on each. They were basic rectangular boxes that I cut and assembled out of spare plywood. The first time, just set the oven into direct sunlight and watch the temperature climb. Preheat the oven for at least 30 minutes. Marshmallows, raw apple slices, or other suitable food to "cook", Construction paper - assorted colors with plenty of black available, Books or other objects that can be used to prop up the over at the proper angle, Analyze data from tests to determine similarities and differences among several design solutions to identify the best characteristics of each that can be combined into a new solution to better meet the criteria for success, Evaluate competing design solutions using a systematic process to determine how well they meet the criteria and constraints of the problem, Apply scientific principles to design, construct, and test a device that either minimizes or maximizes thermal energy transfer.