Solar Energy Essays (1378 words) - Renewable Energy,

Solar Energy Ever since the dawn of time, the sun has been a resource we cannot live or do without, so its not such a shock that man has come up with the idea of solar energy. Solar energy had many uses. Some can be dangerous and some, a very valuable asset to the modern world. Solar energy is energy derived from the sun in a form of ultra-violet rays. Its was first applied to use in 212 B.C., by the Greek genius Archimedes. Solar energy was used to defend the habor of Syracuse against the Roman fleet. Archimedes used a mirror or "burning mirror" as they had called it, to set fire to the ships of the Roman fleets while standing on shore (McDaniels 83). It wasn't until 1615 when Salomon de Caux constructed the first solar device; a solar engine. His device was made of glass lenses, supporting frame, and an airtight metal vessel containing water and air. This produced a small water fountain when the air heated up during operation. This was considered to be more of a toy than a device, but it was the first published account of the use of solar energy since the fall of the Roman Empire (Cheremisinoff 1). Some other use of solar energy after that was the solar roof and the solar oven. The solar roof was thought up by Harold Hay. In a solar roof system, water is contained in a clear plastic bag and it is placed on a black metal roof. Hay got the idea while traveling in India on a technical aid mission for the U.S government. While there, he noticed that many people were living in rusty, sheet metal shacks, which were hot in the day and cold at night. Hay's plan was to remove the insulation from the roof on winter days so that the roof would get hot, and Replacing the insulation at night to allow the shack to be warm through the night. Then in the summer, he would so the reverse of what he did in winter to let the house cool at night and replacing the insulation in the daytime to block out the heat. Then over the years, Hay and a man named John Yellott constructed a 3- by 3.7-m building using water basins as the actual roofing material. During the summer, a slab of foam insulation was rolled back at night, and the water would become cold through the night sky evaporation. Since the water supply sat directly on a metal ceiling, it absorbed the heat from the room and kept the building air-conditioned all day. During the winter, the movable insulation was rolled back in the daytime which allowed for it to collect heat. This generated enough heat into the house through the ceiling at night to keep the room comfortable (McDaniels 179-181). Then there was the solar cooker. Developed by Augustin Mouchot in France and by John Ericsson in the United States in the nineteenth century. They wanted to develop a solar cooker that not only reached high temperatures, but also was to be used as a means of heat storage enabling food to be cooked after sundown. Mouchot built a solar steam engine that operated a printing press in Paris in 1882. In the United States, John Ericsson invented what he called the "Ericsson-cycle" which was a hot-air engine for the making of solar heat. The sun's rays would be concentrated with the use of a parabolic reflector, which was designed to track the sun across the sky in order to keep a constant power output. (McPhillips 86-89) There was also the solar oven. In 1837, and astronomer from England named John Fredrick Herschel introduced to the world a solar oven. He built a small solar oven while on a trip to Africa's Cape of Good Hope. He constructed it as a mahogany, painted it black and buried it in the sand for purposes of insulation. a doubled-glazed cover, which was the only portion of the oven left exposed, serve to limit heat losses through the top, while at the same time, letting in sunlight. The maximum temperature of the oven was of about 240 degree F and it was used throughout his expedition by him and his staff to cook both meat and vegetables (Regino 5). Not all solar energy inventions and discoveries were good. Some solar energy is dangerous. One for example would be lasers. Laser, an electromagnetic wave that is made up of excited atoms. It