Plants, by shear desire to survive have developed the worlds most efficient and reliable power supply by way of photosynthesis. Scientist for years have tried unsuccessfully to duplicate the process of photosynthesis. However, for the purpose of this paper, I will compare and contrast how energy and electricity is generated through photosynthesis and a semi-conductor based solar cell. In addition, this paper will explain how both processes relate to the laws of thermodynamics. Photosynthesis and semi-conductor based solar cells have many similarities. They harvest sunlight, split water molecules, and produce an output of energy. Plants harvest sunlight through direct contact. Solar cells also harvest sunlight through photovoltaic (PV) panels. Sunlight is absorbed by semiconducting materials much like, how chlorophyll harvests sunlight in plants. Both photosynthesis and semi-conductor based solar cells are of great value because of their outputs. The process of photosynthesis produces oxygen and permits plants through absorption of sunlight to produce food. During photosynthesis, plants combine energy from the sun with carbon dioxide to convert water molecules into hydrogen, electrons, and oxygen. Photosynthesis also produces the fossil fuels petroleum, natural gas, and coal. The light reaction of photosynthesis is very similar to the creation of electricity by way of solar cells. The electrons in the solar cell capture light energy; from there they are transformed into a high energy level where they are accepted by the wire to run the semi-conductor motor (Virtual Biology, 2002). Both processes are also similar because electrons are lost. Electrons that are lost in solar cells are replenished when the electrical circuit is complete. This is comparable to lost electrons in photosynthesis that are replenished by splitting water. Although both processes are very similar, they
References: CliffsNotes.com. (2010, October 25) Laws of Thermodynamics. Retrieved from http://www.cliffsnotes.com/study_guide/topicArticleId-23791,articleId-23691.html Hunter, P. (2004, May 14). The promise of artificial photosynthesis. Prosper Magazine. Energy Bulletin. Retrieved from http://www.energybulletin.net/node/317 Physics Planet is an on-line A-to-Z reference of physics. The goal is to educate visitors on various aspects of physics. The website covers a variety of topics ranging from astrophysics to forces and scientist. (http://www.physicsplanet.com/articles/three-laws-of-thermodynamics). Virtual Biology Course is an on-line A-to-Z reference of biology maintained by Dr. Paul Decelles and is part of the Johnson County Community College website. The goal is to cover the major concepts of biology. The website covers a variety of topics ranging from evolution to human organ systems and classification. (http://staff.jccc.net/pdecell/photosyn/solar.html).