РефератыИностранный языкReRenewables America

Renewables America

Renewables, America’s Energy Source For The Future Essay, Research Paper


Renewables, the Energy Source for America s Future


When many people thing of the United States, they envision a land of freedom, prosperity, and wealth. However, environmentalists see a different land, one containing six percent of the world s population, and yet producing twenty-five percent of the world s pollution. This is because much of our prosperity is direct result of our exploitation of fossil fuels. They provide us with about ninety-three percent of the energy we consume. For this reason, our environment is becoming increasingly polluted, natural habitats are being destroyed, and health problems resulting from pollution are increasing steadily. If our current trends continue, our nation and planet will eventually become uninhabitable. In order to prevent this, we need a new primary energy source that is environmentally benign. This source is renewable energy and is already readily available. The increased use of renewable energy, mainly wind and solar energy, and reduction of dependence on oil is the best way to solve our current energy dilemma.


For the past fifty years, fossil fuels have been the main source of energy in the U.S. They are a great source of power, but unfortunately they also have many setbacks. The finite reserves of fossil fuels are being depleted at a rate one hundred thousand times faster than they are being formed. As supplies decrease we become more and more dependent on the Middle Eastern countries for our supplies of oil, recently, fifty-two percent of imported oil came from such countries. The most significant drawback is the amount of pollution produced by fossil fuels.(5)


These negative impacts can be lessened and even eradicated through the use of renewable energy. There are several forms of renewable energy, with wind and solar power being the most effective.


Wind power is produced by numerous large structures known as wind turbines. Wind turbines consist of rotor blades, a power shaft and a generator. As wind passes through the rotor, aerodynamic lift is created and the rotor spins. This spinning in turn drives the generator and produces electricity. A suitable site for wind power must have at least an annual average wind speed of twelve miles per hour, and in order to fully take advantage of wind, the turbines are built on large towers.(3)


Solar power is the most abundant form of energy on earth. Each day, more solar energy falls to earth than the total amount of energy used by the world s population in twenty-seven years. The fastest growing solar technology is photovoltaic cells. These cells use semiconductor material to directly convert sunlight into electric current. Other technologies include concentrating solar collectors and flat-plane solar collectors. A concentrating solar collector consists of mirrors and lenses that focus light on a receiver. The receiver converts the light to heat and the heat is used to power electricity producing generators or engines. Flat-plate solar collectors are flat boxes containing dark colored metal inside to absorb heat, and glass on top to prevent the heat from escaping. Running pipes underneath these provides hot water, space heating, and several other useful applications. Keep in mind though, solar and wind power is not the only forms of renewable energy.(3)


The other forms

that have potential are geothermal power, small-hydro power, and the use of hydrogen gas for fuel. Small-scale hydro development has been recently revived. Although the sites only produce small amounts of electricity, they have other great benefits. They have minimal impact upon the environment, sites can be developed quickly and expanded easily, also their long life span of seventy years or more and minimal operating costs makes them very cost effective in the long term. Another promising technology is geothermal power. Geothermal power uses the heat below the earth s surface for energy. The heat is trapped in the form of superheated groundwater. This heat is tapped by drilling and the steam is used to turn a generator or for the direct heating of an area. Unfortunately, the cost is high, the drilling has environmental impacts, and it is not necessarily renewable due to the fact that depleted groundwater isn t quickly replenished.(4) Hydrogen fuel is perhaps the most promising of the three. Engines can be converted to run on hydrogen much as they are natural gas. The result is a fuel whose only byproduct is water vapor. However, hydrogen gas is virtually nonexistent on earth and must be obtained through electrolysis. This actually requires more energy than we get out of it. If we use solar power to provide the necessary electricity, hydrogen fuel has the potential to be a very viable fuel.(1) Despite the great benefits of renewable there are a few drawbacks.


Most critics tend to have similar arguments against renewable energy. They say it is unreliable, costly, and uses too much land. The supposed drawbacks are easily dismissed however. It is cheaper than current sources of energy when you factor in such costs as air pollution, strip mining, and nuclear waste disposal. The amount of land required for renewable applications is minute when compared to the amount of land needed for strip mining or the potential amount of land made inhabitable by a nuclear accident. As far as reliability goes, backup storage can be used and solar power could be used only during the day and at night provide energy with one of the other forms such as wind or geothermal. It is clear that renewable energy has many benefits and only a few drawbacks that can be overcome.


If our planet is to still be viable in the next few centuries, renewable energy is the way we have to go. The only thing needed is public support. This can be accomplished by imposing penalties and high taxes on fossil fuels and desirable incentives on the use of renewable energy. Just a few of these include: increase government funding to help spark private interest, reinstate solar panel tax cuts, rewrite electric utility regulations to favor environmentally friendly sources and encourage banks to give favorable lending terms to those who use renewable energy.(2) If the public is fully educated on the benefits of renewable energy, favor for them will increase and in a relatively short period of time, renewables could be providing most of or even all of our energy needs.


Works Cited


1) Nebel & Wright, Environmental Science, Prentice Hall, 1996


2) Melville, Keith, Energy Options, McGraw-Hill, 1992


3) NREL Homepage, http://www.nrel.gov


4) Renewable Energy Website, http://www.casahome.org/renewab.htm


5) Ases Home: Solar Guide, http://www.ases.org/solarguide/fbpdt.html

Сохранить в соц. сетях:
Обсуждение:
comments powered by Disqus

Название реферата: Renewables America

Слов:1104
Символов:6979
Размер:13.63 Кб.