Solar Energy

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Solar Energy

Solar energy is the most ancient kind of energy found on earth, for it is as old as the sun. "Solar" means from the sun. The earth is only one of the many planets which is bathed in the sun's overflowing energy. Every second the world receives 95.8 trillion watts of power…just think about that for a minute. Think about how much power the earth just received in the time it took you to read this sentence? It is well beyond the amount of power used in one day. It has the potential to satisfy all our energy needs forever without ever having to use the pollutive fossil fuels ever again. "The problem however, does not lie in the limited source, as do fossil fuels, but in harnessing it." Every day solar energy is being used all around us. In fact, it is the indirect source of all energy and life on earth. Hopefully, with continued research, we will be in a place one day where we can directly rely on the sun for all our energy needs, and never have to use pollutive fossil fuels, or nuclear power ever again (Cross 124).

It is hard to say when solar energy was first used by humans to make life easier. As far as we know, people have always used the sun's visible range of light to see by, as well as to sit in the sun to keep warm. "Some of the first ancient cultures to use solar energy as heating were those from the deserts, and dry areas." In Egypt, Libya, and Algeria, where the sun is fiery hot in the day, but reaches freezing temperatures at night, builders discovered that thick walls of mud could solve this problem. During the day, they would absorb all the sun's energy and leave it cool as a cave inside, and at night, the walls would radiate their stored heat, and keep it fairly warm inside.

These ancient people also discovered how to use the sun's energy to preserve food by either drying fruits or meats in the sun, or baking them. They found techniques to bleach cloth and cure animal hides. Whether by accident, or deliberate experimentation, these ancient cultures discovered that the sun was an incredible source of power (Bower 36).

Throughout history people have experimented with the many uses of the sun's power. In the 17th century, scientists in Europe began rediscovering the sun. When a French scientist proved that the sun's rays could melt copper and fuse pieces of iron if concentrated and focused through a glass prism, people began to see the usable power of the sun. In the 1690's an Italian scientist invented a solar furnace that was so hot it could shatter a diamond, one of the hardest substances on earth (Asimov 119).

The real question around the beginning of the 19th century concerning solar energy was "could the sun produce electricity directly?" The main motivation behind this desire was that electricity could be stored in a battery, and used later. It would not be necessary to use the device in the sunlight. All inventions failed, until Frank Shuman, an engineer from Pennsylvania finally made a breakthrough. He built an experimental plant that used black troughs covered in glass with a few inches of water. When exposed to the sun, the water got very hot, causing it to circulate and power an electric generator. His data was so convincing that he got financial backers and built the world's first solar electric power plant in Egypt. However, the Eastern Sun Power Company went out of business even though it was using free fuel. It didn't produce enough electricity for the area that it used, 14,000 sq. ft of sun-collecting land (Zweibel 48).

In 1954 Bell Laboratories invented the first photovoltaic (or solar) cell, made from the semi-conductor silicon, and other elements. It was the first way to convert sunlight directly into electricity. When the space program was launched in the 60's, it became obvious that solar power was the best choice for satellites, because they can be small and light, and don't need heavy batteries or other types of generating electricity. After NASA and other major...
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