gendreau.kashmanian.wiki.spring.2011

**__ El Problemo __** The largest problem that we have is finding a renewable source of energy that is environmentally friendly. There have been a lot suggestions and ideas on how to solve this problem; however, there is another issue. Though we can produce ways of creating renewable energy, many of the ideas prove to be energy inefficient, meaning that it’s not worth it!The force that controls this problem lies in the hands of consumers. Since the early 1900’s, gas and oil consumption have steadily increased and as of right now, it doesn’t seem like it is going down. Based on the following graph, one can see that oil and gas demand will continue to rise. As you can see by the graph above, the demand for gas and oil is increasing, even though it might not be rapidly increasing just yet, this still is a problem. As the demand increases, the number of barrels per year is rapidly increasing. The last time we had large amount of gas and oil discoveries was in the 1970’s and I honestly don’t see it going back to where it was at that point. Another driving force of this problem is that people are recognizing the consequences of the irresponsible use of our resources, but it seems as if they are trying to ignore it and this needs to be stopped. A Lot of ideas have surfaced as to how to solve this global problem. Some of these ideas include hybrid cars, renewable energy such as wind or hydro power, nuclear power, solar energy, bio-diesel, corn-based-ethanol, and many more. The goal of this project is to focus on how wind and hydro power are the best and cleanest option to solve this problem. We need to prove that wind and hydro power can be an alternate source of energy that is efficient, not only for our wallets, but also the environment. **__ The Solution __** Wind and hydro power are the solution to this problem because of many reasons. Water and wind are sources of energy that can be found all over the world. Air surrounds us. It is what makes us breath there has to be plenty of it on our planet. Also our plane is covered over 3/4 by water, which can be used for energy. Think of all the energy that we could produce with all of this water. We would not have to rely on gas and oil for everything we use that needs energy. So now it comes down to us to make these ideas work. The country, no, the world depends on us finding a renewable source of energy, and the answer is right here. **__ How Wind Power Works __** The most popular way to utilize wind energy is a wind turbine which is what we will be explaining about. Now believe it or not, wind power starts with the sun. When the sun heats up a particular area of land, the air that surrounds that land mass absorbs a good amount of that heat. At a given temperature, that pretty hot air begins to rise very fast because a given volume of hot air is lighter than an equal volume of cooler air (the particles are much more spread out). Much Faster-moving (very hot) air particles put more pressure than much slower-moving particles, so it takes not as many of them to maintain the normal air pressure at a given elevation. When that lighter hot air all of a sudden rises, cooler air flows very quickly in to fill the space that the hot air leaves behind. The air that rushes in to fill the gap is wind. If you place an object such as a rotor blade found on a wind turbine, in the path of that wind, the wind will push on it, transferring some of its own energy of motion to the blade. This is how a wind turbine captures energy from the wind. Doing this causes the prop to move in revolutions. The moving prop then moves a shaft that operates at a low speed. At the end of this shaft there is a gear which is connected to another gear on a faster moving shaft. This faster moving shaft helps transfer all of this energy to the generator which stores power and produces electricity to power may things i.e., MMA. Wind turbines also have devices in them that will make them rotate into the direction that the wind would be blowing in. In order for wind turbines to even operate they need to be set up in areas that have a high wind velocity year round. These areas can be hilly, higher than normal altitudes, very large wide open fields, and on the ocean. Although it can be pain to get a permit to install windmills in some of these areas, in the end it h(minus the shaft, prop, and generator parts). The same concept of wind transferring energy works for a sailboat. When moving air pushes on the sail, it causes the boat to move. The wind has transferred its own energy of motion to the sailboat. Below is a neat little picture on how it works. **__ How Hydro Power Works __** The most popular way to utilize hydro power is by a hydropower plant and its components which is what we will be talking about next. What do you think causes a hydro turbine to work? That’s right folks, water is what makes it work. And what are those great big bodies of water that flow through the earth’s continents? That’s right, rivers, is the correct answer. No all of that flowing water in rivers should be used for something. I mean, you can only imagine how much energy is in flowing water. For example, If you have ever been white-water rafting, then you've felt a small part of the river's power. White-water rapids are made as a river, carrying a large amount of water downhill, through a narrow passageway. As the water is forced to go through this opening, its flow increases. Foods are another example of how much force a huge volume of water can have. Hydropower plants utilize water's kinetic energy and they use basic mechanics to turn that energy into electricity. **Hydropower plants ** are actually based on a very, very simple concept which basically is, water flowing through a dam turns a turbine, which then turns a generator. Here are some things you need for this to work correctly. Ok, the first thing you need is a dam and no it’s not like a “god dam” for you __Beavis and Butthead__ fans. Most hydropower plants rely on a dam that holds back water, creating a large reservoir. Often, this “reservoir” can be used as a recreational lake for people to play and swim at. Now next you need an intake. These are gates on the dam that open and the force ofgravity pulls the water through the penstock which is a pipeline that goes to the turbine. The water flowing through the pipe increases its pressure as it flows farther down as it makes its way towards the turbine. No when the water hits and turns the big blades of the turbine, a series of magnets inside the generator also turn. The turbine is attached to the generator by means of a shaft. Giant magnets rotate past copper coils, producing alternating current (AC) by moving electrons. The next thing that happens is the transformer inside the powerhouse takes the AC and turns it to higher-voltage current. Next you have power lines. Coming out of every power plant come four wires: the three stages of power being produced at the same time plus a neutral or ground common to all three. The power lines go out to power a lot of places. And lastly we have outflow. This is when used water is carried through pipelines, called tailraces, and re-enters the river downstream. We are not going to get into how each and every little part is made up but that’s the dumbed down version for you. Here is a picture of hydropower plant and its components. **__CO2 Emissions __** Considering that the sources of energy used for wind power and hydro power is air and water, there would be a 0% gain of CO2. The only time that carbon emissions would be produced would be from the machines used to construct the wind or hydro plant. So in this case, there is no need for a stoichiomertric equation to be provided. **__Water Generation __** Considering that both wind power and hydro power do not generate or purify water (hydro power uses the kinetic energy of water to make power), the amount of generated or purified water will not be needed. **__The Ups for both Wind and Hydro __** Both of these alternate sources of energy are environmentally friendly. They do not give off carbon emissions after they are initially built and they use natural resources that can be found almost anywhere which means that the resources are abundant. They also have easy payback meaning that, over a few years, they will payback the initial investment and continue to provide energy and profit. They have very little maintenance because they are constructed in a very simple manner and he they do their job is not too complex. Also few employees are needed to run and maintain them which will cut the annual costs to keep the turbine running. So judging by this, it seems that wind and hydro power has a lot of positive things to offer. "So I support comprehensive legislation that would overhaul our energy taxes; signal the market we're in this for the long run by extending for 10 years the production tax credit..." "We absolutely need the turbines."__ Senator Hillary Clinton, NY   **__ The Critics Point Of View (A.K.A. The Downs) __** The bad things that come out of installing a wind turbine or a hydro plant would have some effect on its surroundings. The installation of one of these would have the chance of disturbing the natural habitat in which it is placed in. A wind turbine farm could disrupt the migration patterns of birds and it could also be the cause of death for some birds. They could also cause the destruction of forest, where many species exist. Hydro plants have the possibility of disturbing fish ecosystems. If either of these were mass produced it one area, they could take up a lot of valuable space. They can also be very dangerous if a wind turbine of a hydro plant were to explode. And lastly thing that’s gets most people who live around them mad is that they can be very loud. These negative qualities also have to be taken into account. "Only after the last tree has been cut down. Only after the last river has been poisoned. Only after the last fish has been eaten. Only then will you find that money cannot be eaten". __Cree Indian saying **__ Do Wind and Hydro Power Take Up A Lot of the Worlds Energy Supply? __**   This is a good question. Wind and Hydro Power do not make up much of the world's energy supply mainly because we have a functioning system and have not had the need of change. Now that we are becoming aware of the consequences of using other sources of energy (oil, gas and coal), Global warming, not enough OPECs (Organization of the Petroleum Exporting Countries), and slow decline of resources, renewable energy and fuel sources are on the rise. Right now wind and hydro Power only make up less than a percent of the nation's energy source. Some reasons as to why this is happening include, not enough support from large organizations and government departments, insufficient funds, and lack of free space to install them. **__ To Help or to Hurt? __**   It seems today that wind and hydro power could possibly the answer to many of our energy problems. They partially solve the consumption of gas and they cut down the amount of carbon emissions. Because turbines do not produce emissions, only the fuel used to build these structures will produce the only emissions they will give off. Over long period of time, they will have a huge impact on the amount of greenhouse gasses and they possibly may cut down the price of oil. The thing is, they could hurt natural habitat which we have to work at to preserve. You cannot forget to take these negatives into account because that could lead to yet another problem.In order for alternative energies like this to be used, they would need lots of initial money to get it started, support, and vacant space. This would allow for a mass production of energy to be produced from nothing but our natural and very abundant resources. It would however be very hard for wind and hydro power to be the only source of our energy because there is not enough space on the planet for us to generate the amount of energy we use today and if the human population keeps increasing, they definitely will not be able to provide us with all of the energy we need. **__ How a Wind Turbine is Utilized in My Life __** I go to Massachusetts Maritime Academy and they have the largest generating output wind turbine on the Cape and The Islands. In its lifetime it has generated 4,950,941 kWh of electricity (maritime.edu). It has avoided producing 5,998,243 pounds of CO2 since its installation in 2006 (maritime.edu). This turbine is not loud and it does not seem to be disturbing any natural habitat. This turbine is an essential part of our school and it shows and proves to the world that we do have a way to somewhat escape from the use of, oil, gas, and other fossil fuels. Though the wind turbine is not the only thing that MMA uses to be a greener place, we also have solar powered lights and we also have recycling competitions. After understanding what these alternative resources of energy can provide for us, we believe that it would be a very smart investment for the future generations to come. **__ Works Cited __** [] [] [] [] [] [] Coal is one of the many options that this country may resort to for energy when oil runs out. It is a non-renewable energy source because it is a fossil fuel. Although it’s nonrenewable it’s very abundant. The United States has large coal deposits in many places in the country. It has nearly one quarter of all the deposits in the world. The deposits do not have to be shipped here on tankers like oil does. This means that coal costs much less for about the same amount of energy. The US used coal to produce about 1,757,484 thousand megawatt hours of electric power in 2010 alone.*1 Coals output numbers dwarfed oil outputs at just over 24,000 thousand megawatt hours. *1 In 2010 coal made up about fifty percent of all electrical power produced in the United States. Coal is also expected to last much longer than oil because it is much more plentiful. The coal reserves in the U.S are expected to not be depleted for another 225 years.*3 This is much longer than oil which is expected to run out within the next fifty years. Coal like most fossil fuels is burned in furnaces to produce electricity. The coal must be crushed before it can be burned in the boiler. The coal is burned at very high temperatures which produces large amounts of heat. This heat is transferred into water by shell and tube heat exchanger which causes it to boil. The boiling water creates large amounts of steam which is then piped through large turbines. The steam causes these turbines spin at high rates of speed which maximizes efficiency. The turbines are attached to electricity generators by a set of speed reduction gears. The generators put out current which can be sold to people who need the electrical energy. media type="youtube" key="SeXG8K5_UvU" height="349" width="425" A great advantage of coal is found all across the United States. Which is one of the reasons it is so cost effective. Large amounts of it are found in West Virginia and in the Missouri areas of the United States. These deposits started off as large swamps with plentiful organic life hundreds of millions of years ago. After the organic matter in the swamps died they began to pile up on top of each other creating thick deep swamps with new life continuing to grow on top of it. Over time these swamps became completely buried and covered with dirt and debris until they were sealed under the ground. Over millions of years, pressure and heat from the earth turned the swamps into lignite and then into the coal we mine today. The older the coal is that is mined, the more energy value it has, in turn making it more valuable.
 * __ Wind, Hydro, and Coal __**

*4*5 Some arguments against coal are how dangerous getting it out of the ground is. Each year coal miners die in accidents all over the world trying mine coal deposits. Also the mining of coal whether it is by mine shaft or open pit mining can be very harmful to the environment. Though largest argument against coal is the amount of the greenhouse gas, carbon dioxide it produces when it is burned in power plants. Although coal produces the most electricity out of any fuel source in the United States it also produces the most carbon dioxide. In 1998 coal produced 1,799,762 thousand metric tons of carbon dioxide emissions. This number is much more than petroleum, natural gas and other fuels combined. The carbon dioxide output of coal is also higher per kilowatt hour than any other energy source. Coal makes 2.117 pounds of CO2 per kilowatt hour, petroleum makes 1.915 pounds and Gas makes 1.314 pounds. *2This means coal burns much dirtier than other fuels for the amount of electricity you get out of it. Another concern with coal burning is acid rain. Because coal has many impurities in it such as sulfur, it can create sulfur dioxide when burned. This sulfur dioxide can mix into rain clouds which then creates sulfuric acid rain droplets. The droplets fall back to earth where they can do damage to all sorts of things. |||||||||| **Table 1. Summary of Carbon Dioxide Emissions and Net Generation in the United States, 1998 and 1999 ** Although coal may burn much dirtier than other fuels progress is being made towards clean coal technology. This technology promises large reductions in carbon dioxide emission rates from power plants. One type of clean coal technology is one that washes the coal before it is burned by crushing the coal and letting unwanted purities be sifted out of the coal. This allows for the coal that is burnt to be of much higher quality reducing chemicals such as sulfur. *4 Another clean coal technology is called carbon capture. This uses steam shot at exhaust gases to collect the outgoing carbon dioxide. This dramatically reduces the amount of carbon dioxide that enters the atmosphere. The carbon dioxide is then pumped into the ground where it stays. One more technology that has come out recently is called gasification. In gasification the coal is mixed with steam and air. This mixture pulls the energy from the coal which increases the efficiency of the plant up to fifty percent. There are a few drawbacks to clean coal technology. It “will increase the cost of producing electricity by 25 percent to 40 percent”.*5 Even though this clean coal will increase the cost of production of power this technology is still the most viable clean coal technology out there and will be seen more and more into the future. I believe coal is a great solution for America with the rapidly rising prices of oil. We have a very abundant source of energy beneath our very feet. The cost of producing energy from domestic coal is a much better option than oil and natural gas. Oil and natural gas aren’t nearly as plentiful as coal is in the US. From the table I have seen coal is not much dirtier than oil when burned to make electricity. The US must stop relying on foreign countries with unstable governments to provide our major source of power. Eventually the oil will run out or turmoil in the countries that produce it will cause prices to skyrocket. Coal will be a reliable source of energy for years to come. Coal is definitely not a permanent solution to the energy crisis though. In my mind it will simply give us another two hundred years to figure out a self-sustainable, efficient and practical form of energy production. Other forms of energy production such as wind and solar have not been developed enough to be practical and a major producer of electricity in the United States. The most viable sources of energy I can see powering most of the United States in the future will be coal and nuclear. **__ Works Cited __** [] [] [] [] [] []  []  4. []
 * || **1998 ** || **1999 **p || **Change ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">PercentChange ** ||
 * **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">Carbon Dioxide **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> (thousand metric tons) <span style="font-family: 'Arial','sans-serif'; font-size: 10px;">a ||   ||   ||   ||   ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> Coal || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1,799,762  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1,787,910  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-11,852  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-0.66  ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> Petroleum || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">110,244  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">106,294  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-3,950  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-3.58  ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> Gas || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">291,236  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">337,004  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">45,768  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">15.72  ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> Other Fuels <span style="font-family: 'Arial','sans-serif'; font-size: 10px;">b || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">13,596  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">13,596  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-  ||
 * **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> U.S. Total ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">2,214,837 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">2,244,804 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">29,967 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1.35 ** ||
 * **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">Generation **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> (million kWh) ||   ||   ||   ||   ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> Coal || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1,873,908  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1,881,571  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">7,663  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">0.41  ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> Petroleum || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">126,900  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">119,025  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-7,875  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-6.21  ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> Gas || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">488,712  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">562,433  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">73,721  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">15.08  ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> Other Fuels <span style="font-family: 'Arial','sans-serif'; font-size: 10px;">b || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">21,747  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">21,749  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">2  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-  ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> **Total Fossil-fueled** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">2,511,267 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">2,584,779 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">73,512 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">2.93 ** ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> **Nonfossil-fueled** <span style="font-family: 'Arial','sans-serif'; font-size: 10px;">c || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1,105,947 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1,106,294 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">347 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">0.03 ** ||
 * **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> U.S. Total ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">3,617,214 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">3,691,073 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">73,509 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">2.04 ** ||
 * **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">Output Rate ** <span style="font-family: 'Arial','sans-serif'; font-size: 10px;">d <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> (pounds CO2 per kWh) ||   ||   ||   ||   ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> Coal || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">2.117  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">2.095  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-0.022  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-1.04  ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> Petroleum || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1.915  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1.969  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">0.054  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">2.82  ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> Gas || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1.314  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1.321  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">0.007  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">0.53  ||
 * <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;"> Other Fuels <span style="font-family: 'Arial','sans-serif'; font-size: 10px;">b || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1.378  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1.378  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-  || <span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-  ||
 * **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">U.S. Average ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1.350 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1.341 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-0.009 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-0.67 ** ||
 * **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">U.S. Average ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1.350 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">1.341 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-0.009 ** || **<span style="font-family: 'Helvetica','sans-serif'; font-size: 13px;">-0.67 ** ||
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 * 3) http://www.mnn.com/earth-matters/translating-uncle-sam/stories/where-does-coal-come-[|from]

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