Did you know that on a sunny day, an acre of land receives almost 4,000 horsepower of heat energy? Or that a square mile receives about 2,500,000 horsepower? This is the vital alternative source of energy we must harness to heat our water, heat and light our buildings, supply us with electricity, and cook our food.
The sun is vital to our lives. It provides heat to our planet, it provides food through plants for us to eat, and light for us to see. And most of us take this all for granted. The sun provides us many times more solar energy than all the fossil fuels, including nuclear!
It is not unusual to get a solar oven cooker over 350 degrees F. We can bake bread, cookies, and cook many other food items. We produce this heat by reflecting, concentrating, and adsorbing the sun's rays in the same way the dark seat in your car will get hot after being in the sun. This is called the "Greenhouse effect". Glass lets the solar heat in but prevents much of it from escaping. Solar collectors for heating water are painted a non-reflective black and we use this same technique in our solar oven.
Any non-transparent surface gets hotter when the sun's rays strike it perpendicularly. In the early morning or late afternoon, the sun's rays reaching the earth are weaker (more atmosphere to come through) and are a maximum at noon. To overcome this reduced solar energy in the morning and afternoon, we "track" the sun by moving the cooker so the sun's rays fall directly on the reflective panels. Even in the northern areas or in the winter when the sun is low in the sky, the cooker will do well. Even in the winter when the air temperature is only 15 degrees F., food will burn if left in the oven too long. (See helpful hints).
Solar Cookers are becoming available in many countries today and are being mass produced in South Africa. To reduce pollution and to reduce deforestation, Solar Cooker International, a non-profit group in Sacramento, California, is teaching people throughout the world how to build their own cookers with materials available in their own locality. The goal of Solar Cooker International is to teach half the people in the world to cook with solar by the year 2,010.
Solar Cookers can be purchased through AEA and are advertised in magazines in the United States such as "Solar Today" and "Home Power".