Solar Photovoltaic Cells Essay -- Solar Energy Heat Sun essays

Solar Photovoltaic Cells Solar energy is a general term referring to any process that turns sunlight into energy. Two common forms of solar energy are used today: Solar photovoltaic cells and solar thermal technology. Solar thermal technology uses the heat generated from sunlight to create energy. Most commonly, this can be used to heat water for a house or other projects. Or, with increasing complexity, it can turn the heat into electricity. Unfortunately, much of this technology is too expensive and complex to be practical in the United States on any large scale. However, solar photovoltaic cells are a far more promising technology. They provide a simple way of turning light directly into energy. This paper will examine how this technology works on a basic level while accessing the possible benefits and problems this technology has. It will also examine possible technology in the future in an attempt to overcome these problems. How solar photovoltaic cells work: A photovoltaic cell uses semiconductor material to transform light into electrical energy. Photons from light hitting the material excite electrons, releasing them from their atoms into the material. Once electrons are excited, they are able to move freely within the material. The semi-conductor then serves to force the electrons in the desired directions. By creating a junction of a p and n type semiconductor, an electrical potential is created. The electrons move from the n-type to the p-type. Meanwhile, the positively charged atoms move from the p-type to the n-type. As a result, the n-type material gains a positive charge and the p-type gains a negative charge. When an electrical circuit connects the p-type and n-type ends, difference in e... ...rrent conventional energy. It has promising chances of reducing carbon dioxide emissions and thus reducing global warming. But, it sill cannot compete economically with current energy means and as a result, more research must be dedicated into the cause in order for its benefits to be fully realized. Works Cited Berinstein P. 2001. Alternative Energy: Facts, Statistics, and Issues. Wesport (CT): Oryx Press; 208p. Current Solar Systems: Modern Photovoltaic Solar Cells. http://www.personal.psu.edu/users/t/s/tss178/pvcells.htm [2004 Oct 19] Ramage J. 1997. Energy, A Guidebook. New York: Oxford. 194p. Sorensen B. 2000. Renewable Energy: Its physics, engineering, use, environmental impacts, economy and planning aspects. 2nd ed. San Diego: Academic Press. 912p. http://www.worldbank.org/html/fpd/energy/subenergy/solar/solar_pv.htm [2004 Oct 18]