Fossil Fuels
It is said that all of the Earth's population can survive a whole year with only fifty minutes of the solar energy we receive. 8 At the same time, nature has found ways to store the Sun's energy when light is not present, i.e. transform it from solar energy into biological/chemical energy. Through the complex process of photosynthesis, leaves in all the different types of vegetation in the planet (and even some bacteria!), 9 use the Sun's light to produce carbohydrates (C 6H 1 2O 6) and release oxygen (O 2). However, the photosynthetic reaction takes place because carbon dioxide (CO 2) and water (H 2O) are also present; all these atoms and molecules form the traditional chemical representation of photosynthesis:
6 CO 2 + 6 H 2O + Light Energy (hΝ) —> C 6H 1 2O 6 + 6 O 2
From the equation, when CO 2 and H 2O interact in the presence of light, several complex reactions take place that regroup and add atoms until carbohydrates (C 6H 1 2O 6 ) are produced and O 2 is released. When breathing, we exhale the CO 2 plants need for photosynthesis and, in exchange, we receive oxygen. This makes photosynthesis a life-sustaining process.
This stored, photosynthetic energy in the leaves of plants is at the bottom of every web of life or food chain; as animals and man consume plants directly or indirectly, this potential energy can then be converted into kinetic energy (work). What's more, through thousands of years and earth processes, plants have been transformed into carbon, petroleum, and gas, the fossil fuels that, according to the Energy Information Administration (EIA) in the chart above, have the highest percentages of use in powering our country.
Petroleum
Petroleum or crude oil is extracted from deep inside the earth and ocean floor to be refined or separated into products like gasoline, diesel, and jet fuel. It is also extensively used in manufacturing goods we use in daily life, like tires, crayons, DVDs, etc. It is a very efficient source of energy since one barrel (about 43 gallons) of petroleum can yield 45 gallons of useable fuel; 10 that is, there is a gain when the crude oil is being processed.
Even though the world has been using petroleum extensively since the late 1800s, it is calculated that we have only used 1 out of a total of 12 to 16 trillion barrels (2008 figures); it is argued that if we eventually transition away from a fossil-fuel energy economy it will not be for a lack of supplies but rather because of better-quality energy sources substitutes. 11 This argument has challenged the "peak oil" theory which claims a decline in oil production because a maximum of extraction has been reached. In fact, there have been five times in the petroleum history when it was claimed we had reached a peak and there would not be new resources to develop or major advances in oil production. However, in spite of a decline from 1985 to 2008, production has been steadily increasing. 12
Geologists use diverse procedures for finding oil; these range from examination of surface rocks and topography, sometimes aided by satellite images, to seismology "creating shock waves that pass through hidden rock layers and interpreting the waves that are reflected back to the surface." 13 When the site has been selected, a rig is built and the drilling operations start. Once the well's final depth is reached, the drilling apparatus is removed, and the flow of oil into the well starts; a pump is later set upon the well head. From the well, petroleum is transported through an interconnection of pipelines that brings it to the refining industries. In the US, although there are 31 states, including coastal waters, where crude oil is produced, 56% comes from only five states: Texas, Alaska, California, North Dakota, and Oklahoma. 14
Natural Gas
In the last two decades, the natural gas industry has been revitalized. New technologies, diversification and findings have made it more available and cheaper, surpassing coal as one of the main energy sources. Additionally, most of the natural gas used in the US is actually produced in the US which helps our economy become less reliant upon importing energy sources from other parts in the world. This fossil fuel is commonly used for heating and cooking, but it is becoming an important source for generating electrical current and powering motor vehicles.
Like petroleum and coal, natural gas was formed through the decaying of plants and animals (organic matter) accumulated in layers, changed to rock, and trapped deep inside the earth. Even though it was originally a byproduct in the production of petroleum, nowadays, it is transported through pipelines from the petroleum fields to the manufacturing industries. New, and once considered challenging, natural gas reservoirs are been exploited and studied with great success and estimates figures are skyrocketing. Fraccing or fracking, also known as hydraulic fracturing, is one of the most recent technologies through which underground rocks are fragmented allowing the gas to flow out. 15 Other natural gas breakthroughs include tight gas, shale gas, coalbed methane and methane hydrate.
The main component of natural gas is methane (CH 4), a gas made up of one carbon atom and four hydrogen atoms; other gases like butane and propane are also obtained when natural gas is produced. Because of its composition, even though when CO 2 is released at the moment natural gas is burned, the amount is half as much as for coal per unit of energy. 16
Coal
Coal is the most abundant and used fossil fuel: 40% of the world's electricity comes from it. 17 Just like petroleum, coal or carbon has taken millions of years to form through pressure and heat which helped keep its energy from photosynthesis stored. Historically, after the extensive use of wood as fuel and the eventual devastation of forests, coal became an easy and cheap energy source to extract. It is excavated through two methods: surface mining and underground mining. The former is less expensive and relies on machines to remove top soil and surface layers of rocks under which lies the coal seam; underground mining, on the other hand, needs elevators to send miners deep into the earth where they use machines to dig for carbon.
Around 35% of the coal production in the US is destined to the creation of electricity. A power plant burns coal to create steam which, in turn, moves turbines to produce electricity. The ingredients in coal can also be separated (for example, methanol and ethylene), and industries can make tar, plastics, fertilizers and medicines out of it.
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