A solar oven is a cooking device that receives 100% of its power from sunlight. This characteristic makes a solar oven environmentally friendly as well as portable, because it requires no gas or electricity to operate. It's also easy to make and store one, so you won't need to set aside much space.
You'll need the following tools and materials:
Umbrella, Aluminum foil, Cooking pot with lid (black is better), Hacksaw, File, Black duct tape or electrical tape
Hammer, Beaker tripod and wire gauze, UV protection glasses or sunglasses with polycarbonate lenses, Work gloves, Meat thermometer (when cooking meat)
Step One: Solar Oven Safety and Design
Understanding the way solar ovens work and knowing the precautions you should take is important before you begin making your own. Basically, a solar oven cooks food by using the light and heat energy contained in the sun's rays. You'll be able to achieve temperatures approaching 300 degrees Fahrenheit by focusing this solar energy. This is hot enough to cook meat as well as boil and sterilize water, but it can also give you a serious burn so you need to be careful whenever you're using it. Wear appropriate protective glasses to prevent your eyes from being damaged by UV light.
Step Two: Apply Aluminum Foil to an Open Umbrella
The reflective surface of a solar oven focuses the sun's heat and light, and aluminum foil makes a fine reflective surface when applied to a fully opened umbrella. Open the umbrella until it locks, and then cut a two-foot strip of foil for each of the umbrella's sections. Next, cover the umbrella's edge with foil, then apply one of the two-foot foil strips to a section of umbrella, ensuring that half the strip is on each side of the umbrella and there's an even overlap on each side of the divisions. Overlap that first strip with another strip of foil on the inside of the umbrella, and apply tape to keep the foil in place. Repeat until the inside of the umbrella is completely covered by aluminum foil.
Step Three: Remove the Umbrella's Handle
While you're wearing work gloves and polycarbonate glasses, cut off the umbrella's handle with the hacksaw, 1 centimeter above the umbrella's locking mechanism. Smooth out the sharp edges with a file, and then hammer those edges toward the center to create a beveled shape. This can help prevent accidental burns while your solar oven is being used.
Step Four: How to Use the Solar Oven
To cook something with your solar oven, first open up the umbrella and lock it into place. Next, point it toward the sun, using rocks or other objects to prop it up and keep it aimed at the sun. Insert the tripod into a level portion of your solar oven and position the wire gauze on it. Fill your cooking pot with food, put the lid on and then place the pot on the wire gauze. Make sure that it continues to point toward the sun while your food is cooking. Finally, when you're cooking meat, make sure you use a meat thermometer to be certain it's cooked to a safe temperature.
