Solar energy is free and readily available to all and using it, to cook in a solar box cooker, saves the energy of electricity, natural gas, coal, batteries and charcoal as it protects natural resources such as our forests. While solar box cooking may not be as fast as more conventional methods of cooking, it has it's advantages.
It's simple, inexpensive and requires no other source of energy at all. You can't burn the food in a solar box cooker and more nutrients are preserved using this method. Using a few inexpensive items you can create a portable solar cooker in about an hour. To learn how, go here: http://solarcooking.wikia.com/wiki/%22Minimum%22_Solar_Box_Cooker
Great for camping or when storms blow down power lines, a solar box cooker is clean, healthy, efficient and requires little tending as do open flame cookers. Used for more than just cooking food, it will heat and purify water and even help heat a sleeping bag or hut by heating rocks that will slowly release the heat overnight.
Solar box cooking became popular during the 1970's with the Save the World' movement of the baby boomers. There was much more to the Hippies than just "make love not war" and "flower power." This generation was among the first to say we were destroying the earth by using renewable resources faster than they were reproducing.
Unbelievable as it may seem, half the world's population cook their meals over wood burning fires. Trees are a renewable resource that can be and are used as energy, even though they play a vital role in cleaning the earth's air, providing habitat for wildlife and stopping erosion.
In countries where clean water is scarce and water borne disease takes a high toll in lives yearly, the solar box cooker is a cheap, easy way to clean water for drinking and cooking. It can be placed outside and left unattended, as there is no danger of fire.
A solar box cooker is basically one foil lined box inside another foil-lined box with rolled newspaper between the two for insulation. An adjustable lid covered with foil, is attached using flexible rubber strips and used to reflect the sunlight into the inner box through a piece of glass laid over the top.
A cooking base is made by covering cardboard with aluminum foil, painting it black and placing it in the bottom of the cooker. This helps transfer the accumulated heat to the cooking vessel. Dark, thin pots with tight fitting lids work best as they absorb and hold the heat more readily. Tight fitting lids also prevent the escape of steam which will fog the glass and slow heat absorption.
Collecting the sun's heat in a solar box cooker is the free way to cook a meal, heat water for a bath, boil water to purify it or to heat a few stones to add to your sleeping bag when camping on cold nights. There are many applications and solar box cookers definitely save energy.