Monday, April 7, 2014

Solar Energy


            Today, the main source of energy is the fossil fuels, such as hydrocarbons, primarily coal, fuel oil and natural gas. They are formed from the remains of dead plants and animals on soil. The problem with the use of these fuels appear when they are burned. The burning of fossil fuels is responsible for the most greenhouse gas emissions over the world. The Environmental and Energy Study Institute says: "the burning of fossil fuels was responsible for 79 percent of U.S. greenhouse gas emissions in 2010, and this number is rising".
            The greenhouses gases lead to huge changes in the earth’s climate. When these gases are released to the atmosphere they trap the electromagnetic radiation from the sun, blocking them to be reflected back to space (BURN). Those gases are methane, nitrous oxide, carbon dioxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride.
            Seeking for other methods to get energy without be harmful to the atmosphere stands out the solar energy. Being considered the cleanest and most renewable energy source available. However, this technology produces less than one tenth of one percent of global energy demand.  It is estimated that the world's fossil fuels reserves will last for 30 to 40 years. On the other hand, solar energy is infinite.
            There are some advantages to the development of solar energy. First, it can be used in remote areas where it is too expensive to extend the electricity power grid, being possible to getting energy to people in distant area from large city, without the necessity of energy transmission by cables. Another advantage is the use in many everyday items such as calculators and other low power consuming.
            Humans have used solar energy for a long time. In 7th Century B.C. they used glass to concentrate sun’s rays to make fire and to burn ants. In 3rd Century B.C. Greeks and Romans, to religious purposes, used to light torches. Also, in 2nd Century B.C., the Greek scientist, Archimedes, used bronze shields to reflect and focus the sunlight, setting fire on wooden ships from the Roman Empire in Syracuse. Nevertheless,  in 1954 was built the actual technology to get energy from the sun light. This technology was discovered by Daryl Chapin, Calvin Fuller, and Gerald Pearson. They developed a silicon photovoltaic cell at Bell Labs that is capable to convert sun's energy into power to run electrical equipments. The efficiency was just about 4% (EERE).
            In 1955, the company Western Electric began to sell commercial licenses for silicon photovoltaic technologies. Then many projects began to be conducted, including by the company Hoffman Electronics, that later improved the efficiency to 14%. Also, the architect Frank Bridgers designed the world’s first commercial office building using solar energy. This solar system still operating.
            Then comes one of the best applications of solar energy, use that technology to support on satellite stations. The idea arised from the scientist and aerospace engineer Peter Glaser in 1965. Then, in 1966, NASA launched to space the first orbiting astronomical observatory, powered by solar energy, with 1-kilowatt photovoltaic array (EERE).
            To the home application the solar energy equipment also has a battery that collect the energy not used during the day to be used at night. However, some complain are argued even today, the use of this technology on days with cloudy skies reduce its effectiveness, making this technology only be harnessed when it is daytime and sunny. Allowing the energy captured by the battery being not enough to provide energy for a long period. In addition the biggest disadvantages of the solar energy is the cost.  The equipment used in the process required high cost to be produced, making the price of the photovoltaic cells not accessible to all population.
            With emphasis, solar energy is one of the most likely way to obtain energy, and can replace the use of fossil fuels. Research is being conducted to get better efficiency in the process, and to decrease the production cost. Therefore, creating interest to the use, and acquisition to this technology by the population. So then we can avoid the worst situations in the present conditions of climate change and avoid future environmental aggressions.


 Igor Lins


References:

"Fossil Fuels". Environmental and Energy Study Institute. Web. April 3, 2014. < http://www.eesi.org/fossil_fuels>

"Solar Energy". National Geographic. Web. April 3, 2014. <http://environment.nationalgeographic.com/environment/global-warming/solar-power-profile/#close-modal>

"The Connection Between Greenhouse Gases, Climate Change, and Global Warming". Burn an Energy Journal. Web. April 3, 2014. <http://burnanenergyjournal.com/the-connection-between-greenhouse-gases-climate-change-and-global-warming/>


"The History of Solar". Office of Energy efficiency & Renewable Energy. Web. April 3, 2014. <http://www1.eere.energy.gov/solar/pdfs/solar_timeline.pdf>

1 comment:

  1. At first, good job Igor! Your text about solar energy make me think about the future of the energy in our lives. The solar energy is a clean energy that can be very useful and easy to manage. Keep going, you are going to be great.

    ReplyDelete