Solar Energy is not a Solution to the American Energy Crisis

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Solar Energy is not a Solution to America’s Energy Crisis With the growing cost of fuel for cars and the rolling blackouts of last summer, the need for an alternative, cost-effective, environment friendly energy source is escalating. Many possible solutions have been presented, such as nuclear power, wind power, and hydrogen fuel cells; prevalent among these is solar power. Solar cells directly convert photons from the sun into electricity (Wikipedia). Solar cells that convert both solar and non-solar light are called photovoltaic cells (Wikipedia 2006). They are made of semi conducting materials, most often silicon (Aldous 2006). The simplest photovoltaic cells power watches and calculators while larger, more complex systems can add…show more content…
Boron only has three electrons in the outer tier, so instead of having extra electrons it has holes. These holes are just the absence of electrons so they have a positive charge and can move about similarly to electrons. (Aldous 2006) An electric field forms when N-type and P-type silicon are put in contact. The free electrons on the N side see the holes in the P side and try to fill them in. All the free electrons of the N-type silicon do not how ever fill up all the free holes in the P-type silicon. At the junction between the two sides the electrons and holes mix and form an electric field as a barrier. This causes the electrons to be able to flow from the P side to the N side but not in the other. (Aldous 2006) When light hits the solar cell, the energy frees the electron/hole pairs. Each photon will free one electron and create one hole. When this happens close to the electron field or if a hole and an electron wander into the field’s range of Solar Energy 4 influence, the field sends the electron to the N side and the hole to the P side. (Aldous 2006) If an external current path is provided then electrons flow to their original side (P) doing work on the way. The electron flow provides current and the electrical field creates voltage, and with voltage and current there is power. (Aldous 2006) Is Solar Power Efficient

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