Fossil Fuels

To be an oil reserve, a deposit must be

An oil reserve is a deposit that has enough oil in it to be economically profitable

The Carbon Cycle

The fossil fuels that we rely on so much come from ancient organisms. Over a span of millions of years, many marine organisms and swamp plants died, decayed, and became buried in thick layers of sediment. Like all living things, their bodies contained carbon, and that carbon was trapped in the sediment that buried them. It stayed there for millions of years. Intense heat and pressure turned the carbon-rich sediment into carbon-bearing fossil fuels, namely oil, natural gas, or coal.

Coal Map

The map shows the major coal producing areas of the U.S. They include the Appalachian Mountain area of the east, areas near the Gulf of Mexico, and the Intermountain West. The most plentiful type of coal in the U.S. is bituminous coal. Note that the lignite coal found in the Gulf of Mexico area is a low-grade coal that is not as commercially profitable as higher-grade coal forms, like bituminous coal. Thus we do not tap, or use, the coal in this area as much as the much higher quality coal of the Appalachians and the Intermountain West. pg 11

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The oceans also store and move large amounts of carbon. The shells of many marine organisms contain carbon. When those organisms die, the carbon becomes a part of the sediment that underlies the oceans. The oceans also soak up some carbon from the atmosphere and hold it as dissolved carbon. Near the ocean surface, some of this dissolved carbon moves back into the atmosphere

5. What type of coal is the most plentiful in the U.S.?

bituminous

Which one may decrease oil supplies?

Increased demand for oil from rapidly developing nations may decrease our known oil supply

Coal Formation

Coal is a solid fossil fuel found in sedimentary rock layers. It formed from the remains of swamp plants that died 300 to 400 million years ago. They were buried in sedimentary layers and compressed by intense heat and pressure over millions of years. Coal starts out as peat; a type of precursor to coal. Then it becomes lignite, a very high-moisture type of young coal. Coal is mostly carbon, but it also contains some sulfur and trace amounts of toxic mercury and radioactive materials. We extract coal from the ground by digging or mining.

What is a problem of offshore drilling?

Offshore drilling is harmful to marine wildlife

The worldwide largest exporter of oil is

Saudi Arabia is the largest exporter of oil worldwide

Electricity Generation

You have probably seen places like this before. It's a power plant where fossil fuels are burned to generate electricity. From the power plant, electricity is transmitted to homes and businesses throughout a given area. How is coal transformed in a power plant into the electricity that runs your home?

2. Coal is made from decayed remains of

ancient swamp plants

7. What type of coal is the most energy efficient when burned as a fuel?

anthracite

1. What is the major gas emitted when fossil fuel s are burned, and what impact does it have on the atmosphere? 2. How does the combustion of fossil fuels affect Earth's carbon cycle? 3. What is flue gas? What harmful substances does it contain, and what is one way we can make it less harmful? 4. Some people argue that we can prevent the environmental harm caused by burning fossil fuels if we burn modern plant material instead of fossil fuels derived from ancient organisms. They say this would add no new carbon to Earth's atmosphere and would not disrupt the carbon cycle. Can you think why this might be true?

1. The major gas is carbon dioxide; in the atmosphere it contributes to an enhanced greenhouse effect and global warming. 2. Combustion of fossil fuels puts large amounts of carbon into the atmosphere, disrupting Earth's natural carbon balance. 3. Flue gas is the billowing cloud of smoke that comes out of a power plant's smokestack. It contains carbon dioxide, sulfur compounds, and toxic mercury. We can spray it with limestone and water to remove sulfur and carbon dioxide. 4. Say, for example, that we gr ow a crop of palm trees. While the trees grow they will remove carbon from the atmosphere through photosynthesis. Then, suppose we harvest those palm trees and burn them as fuel in a power plant. They will then release carbon back to the atmosphere in the form of carbon dioxide gas, but the amount they re lease is offset by the amount they removed when they were growing. There is no net gain or loss of carbon in the carbon cycle. By contrast, because fossil fuels are derived from dead organisms, they do nothing to remove carbon from the atmosphere; they can only release carbon to the atmosphere. This makes for a net increase in environmental carbon dioxide.

3. About how many years ago were most coal deposits formed?

350 million

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After plants and animals die, their bodies decay and release some carbon back to the atmosphere. But some of the decaying material may be buried deep underground for millions of years and turn into fossil fuels. The carbon in these materials moves back to the atmosphere when humans extract and burn fossil fuels.

Oil refining

After we extract oil from Earth, we use it to make everything from automotive oil to plastics to asphalt, grease and wax. Most of the products we use in daily life are somehow connected to oil. The oil industry is the world's largest business. As shown in the diagram, oil refining is the process whereby we heat crude oil to different temperatures to make different useful products. For example, automotive gasoline forms when we heat crude oil to about 150° C, and kerosene forms at about 200° C. This refining process is done at an oil refinery plant.

Oil reserves

An oil reserve is an identified deposit from which crude oil can be extracted for a profit. The map shows you where major oil reserves are located. The largest exporter of oil in the world is Saudi Arabia Total worldwide known reserves of oil are about 3.7 trillion barrels. China, the United States, and Japan are the three biggest oil users. In the U.S., we produce about nine percent of the world's oil, but use about 25 percent of it. Thus, we import a large portion of our oil from other countries. Japan and China also import huge amounts of oil. In fact, Japan imports 90 percent of the oil it consumes. Currently, oil is consumed at about 84 million barrels per day. If this consumption rate remains the same, estimates indicate that we may begin to run out of oil around 2038. Some factors that could extend our oil supply, or make it last longer, include: new discoveries of previously unknown oil reserves energy conservation (would mean less need for oil to produce energy) more use of renewable energy, or energy not derived from fossil fuels (e.g., solar power, wind power, etc.) Factors that could decrease our oil supply, or make it run out faster, include: increased demand from China and other rapidly developing nations increased industrial and transportation needs from a growing human population

6. In what parts of the U.S. is coal found?

Appalachian Mountain area Intermountain West *both of these

Impact of Fossil Fuels on Society and the Environment

Because fossil fuels are so crucial to our day-to-day lives, and to national economies, they are used extensively in just about every part of the world. They are a necessary part of our society, but like many things, they come with environmental consequences. These tabs go over some environmental consequences of fossil fuel use.

Why is natural gas found above oil, and not below it?

Because gas is lighter than the dense oil; it rises to the top

Because they contain massive amounts of carbon

Because they contain massive amounts of carbon, fossil fuel deposits are an important carbon supplier on Earth. The carbon interacts with the environment once we bring these fossil fuels to the surface and burn them. When fossil fuels are burned, they release all that stored carbon into the atmosphere and interact in Earth's carbon cycle. Roll over the numbers on the diagram to explore the steps of the carbon cycle.

Impact on the carbon cycle

But fossil fuels have several large environmental impacts. The biggest of these is how they impact Earth's carbon cycle. Remember that as long as fossil fuels are buried in Earth they have no interaction with the environment. But as soon as we dig them up and burn them, they release massive amounts of stored carbon into Earth's atmosphere. This disrupts the natural balance of carbon on Earth. The carbon dioxide gas that fossil fuel combustion sends up into the air is a major contributor to Earth's enhanced greenhouse effect and global warming. This, in turn, has implications for sea level rises, wildlife, and human populations. Fossil fuel combustion also contributes to several types of air pollution. The incomplete combustion of fossil fuels produces carbon monoxide gas, which is toxic to humans. The combustion of fossil fuels releases sulfur and nitrogen compounds and toxic mercury. The sulfur and nitrogen form acids in the atmosphere and produce acid rain. The mercury is poisonous and can accumulate in our bloodstreams. Also, the use of crude oil often leads to oil spills on land and water. Oil spills can be deadly to wildlife, especially marine wildlife.

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Carbon is an essential part of all living things and is found in all plant and animal materials. Plants remove carbon from the atmosphere and use it for photosynthesis; they later return it to the atmosphere when they die and decay. Thus, carbon is moved from the atmosphere to the bodies of plants by photosynthesis. It is moved to the bodies of animals when they eat plants or other animals that have eaten plants.

Problems With Imports

Coal is found all over the world and is relatively easy to mine. The U.S. government has worked to ensure that we have adequate access to coal and that we are able to import the oil and gas we need. But having to import our fossil fuels can be a problem. For example, in the 1970s, we were not able to import much foreign oil into the U.S. because of political reasons. This lead to a shortage of automobile gasoline and gas had to be rationed. People with even numbered license plates could buy gas on certain days and people with odd numbered license plates could buy gas on other days. The frustration of gasoline shortage s led many Americans to realize how much we depend on foreign oil. But since then, our dependence on oil imports has only increased, not decreased. Currently in the U.S., we use nearly three times more oil than we make on our own; that means we import the rest from other countries. What would happen if political difficulties meant that we could no longer import all that oil?

What can be made from crude oil?

Crude oil can be refined and converted to several products, including gasoline and wax

What is crude oil?

Crude oil is the petroleum, when it first co mes out of the ground, before it has been refined

Slide 2

First the coal is crushed into a powder and fed into a furnace. As the burning coal produces heat, the water in the boiler turns to steam. The steam moves outward and exerts pressure on the turbine making it spin like a pinwheel. This process changes heat energy into mechanical energy. The spinning turbine powers a generator. The magnets attached to the turbine spin. The magnets are enclosed in copper wires, and when magnets spin within a coil of copper wire, electric current is generated. This converts the mechanical energy to electrical energy. The electricity generated then leaves the power plant and passes through a transformer. A transformer changes the power of the electricity into a useable form. From the transformer, electricity heads toward your home through transmission lines. Back at the power plant, a condenser cools the used-up steam moving through the turbine. Coolant water is often drawn from a nearby river or other body of water. This makes the steam condense and turn back into liquid water. The water returns to the boiler and the cycle begins again. Notice that the burning coal produces some waste smoke, just like burning a campfire produces smoke. This material leaves the power plant through a tall smokestack. From here, huge amounts of carbon are released into the atmosphere.

Coal

Fix a smoothie in the kitchen blender, or plug in your cell phone to charge it up, and you are likely relying on a resource that's been called "king coal." Coal supplies nearly half of all electricity used in the U.S., so chances are pretty good that you are connected to it in some way. Luckily for the U.S., coal is the world's most abundant fossil fuel. Scientists estimate that our coal supplies will last another 200 years or so. The U.S. has 27 percent of the world's proven coal reserves. Saudi Arabia, Russia, and China also have large amounts. There are huge deposits of this important natural resource in the Appalachian Mountains of the eastern U.S. Click through the tabs to learn more about coal formation, types, and where we find it.

Natural Gas

If you have a gas stove in your home, you are relying on a second fossil fuel. How is the gas in your kitchen stove different from the gas you put in your car? The gas in your stove is natural gas rather than refined oil. Natural gas is a fossil fuel that forms directly in the environment, and exists naturally in a gaseous form. It is a mixture of gases and is 50 to 90 percent methane. It also contains smaller amounts of propane and butane gas. These are commonly sold as the fuel for gas barbecue grills. Natural gas is usually found above reservoirs of crude oil. Like oil, it can be burned as a fuel. Natural gas supplies about 23 percent of U.S. energy needs. Scientists estimate that global reserves of natural gas will last between 62 to 125 years. Like all fossil fuels, natural gas releases carbon dioxide when burned, and can cause air pollution. Natural gas, however, releases less carbon dioxide than oil or coal. So it is sometimes referred to as the cleanest of the three main fossil fuels. Natural gas gives us a high energy yield and burns cleaner than other fossil fuels, but it is dangerous to transport and can explode if not handled properly. Click each image to learn more about natural gas.

What are the advantages and disadvant ages of using natural gas as a fuel?

It has the advantage of producing less carbon dioxide air pollution than oil and coal. It also gives a high energy yield. However, natural gas has the disadvantage of being dangerous to transport because it is explosive.

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Most carbon in the atmosphere exists as carbon dioxide gas. Carbon enters the atmosphere through plant and animal respiration—it is what you breathe out with every breath. It also enters the atmosphere through the burning of carbon-bearing fuels, like wood and fossil fuels; through t he decay of plant and animal material; and through the production of cement.

automotive

Natural gas can be used in automotive fuel. It produces less air pollution that oil-based fuel, which is why this bus says that it runs on "clean" natural gas.

Since natural gas is associated with oil deposits, from what materials do you think natural gas formed?

Natural gas is derived from the same material as oil. It is formed by the decay of ancient marine organisms that lived about 100 to 500 million years ago.

Natural gas

Natural gas is found and sold in many countries worldwide. Russia, shown here in brown, is the worldwide number one natural gas exporter.

transported

Natural gas is transported throughout the world through long underground pipes. In the U.S., a new natural gas pipeline has been proposed that would run almost 2,000 miles from Alaskan natural gas deposits to the American Midwest.

What is offshore drilling?

Offshore drilling is the extraction of oil from underwater, near shorelines

Offshore oil drilling

Offshore oil drilling refers to the exploration for and extraction of oil from under water, near the shoreline. It is common in the Gulf of Mexico and has potential to be a major source of oil for the U.S. in the future. However, it is more costly than land-based oil extraction and has serious environmental impacts. The biggest problem is the damage done to seas by oil spills. The oil is deadly to marine organisms. Offshore drilling has been banned along many U.S. shores, but in July 2008, U.S. President George W. Bush wanted to lift, or stop, this ban because of rising oil prices, and the demand from many citizens to find new sources of American oil. However, lifting the band required Congressional approval, which it did not receive. In March 2010, newly-elected U.S. President Barack Obama also pushed Congress to lift the ban on offshore drilling, citing the need to find more sources of American oil so the U.S. could be less dependent on other countries to supply the oil. President Obama announced plans to open parts of the Virginia and Florida shorelines to offshore oil drilling.

Offshore oil drilling would mean

Offshore oil drilling would mean more sources of American oil

Oil contains many ___, which burn easily

Oil contains many hundreds of hydrocarbon molecules, which contain carbon and burn easily.

Oil is formed from the decay of

Oil forms from the decay of ancient marine organisms

About how many years ago did oil form?

Oil is a fossil fuel that formed 100 to 500 million years ago

What happens at an oil refinery?

Oil is heated to convert it to useful products at an oil refinery

How is oil refined?

Oil is refined by heating it to various temperatures to produce different products.

Oil Sands and Oil Shale

Oil sands are mixtures of sand or clay and extremely thick deposits of a form of petroleum, called bitumen. They are found in large amounts throughout the world, especially in Canada and Venezuela. Oil sands have only recently been considered part of the world's oil reserves as new technology has made their extraction easier. You will sometimes hear the term "conventional oil." This refers to crude oil deposits of regular petroleum. Oil sands are considered non-conventional oil. Extracting and processing oil sands has a severe impact on the land; the process produces toxic waste, and pollutes air and water. But oil sands have the advantage of potentially expanding our oil supply. Oil shale is another non-conventional source of oil. These are oily rocks that contain a solid combustible mixture of hydrocarbons, called kerogen. When heated, Kerogen can be extracted from the crushed rock. About half of the world's oil shale deposits are in the western U.S. Some scientists estimate that these deposits could meet the U.S. demand for oil for more than 100 years. The drawbacks of oil shale include the high cost of extracting them and the water and air pollution when they are extracted and burned.

Oil Formation

Petroleum or crude oil, as it is called when it first comes out of the ground, forms from the decaying remains of plankton and marine animals that lived 100 to 500 million years ago. When tiny sea organisms die, they are buried under layers of silt and sand on the ocean floor. As the remains became buried deeper and deeper over time, the enormous heat and compression turns them into oil. Oil deposits are buried deep beneath layers of soil and rock in ancient marine sediments. They are not always under water; they could have been formed in areas that were once under ancient seas but are dry land today. We use special drills to extract the oil from beneath the surface for fuel. Crude oil is a thick, gooey liquid containing hundreds of combustible hydrocarbons, which are molecules that contain carbon and that burn easily. The hydrocarbons are derived from the bodies of the organisms from which the oil formed. Crude oil also contains smaller amounts of sulfur, oxygen, and nitrogen.

Word Web: Electricity Generation Vocabulary - turbine - generator - boiler - furnace - transformer - condenser - carbon

Place where fuel is burned to heat water Place where the steam is cooled back into water Place where steam is produced Present in the smoke that leaves a fossil-fuel power plant A special machine that converts mechanical energy to electrical Spins in response to steam; generates mechanical energy A special machine that changes the voltage of electricity

____ lifted a ban on offshore drilling

President George W. Bush lifted the ban on offshore drilling in hopes to find more American oil.

Oil

Putting gasoline in your car is not the only thing you need to do with your car to make it run. You also need to change the oil on a regular basis to keep your engine in top shape. Since gasoline is also derived from oil, your car is consuming fossil fuels in multiple ways. So how does this oil get from underground to your gas tank? Click through the tabs to learn more about oil formation, storage, refining, and use.

Fossil Fuels: Introduction

Stretched end to end, the number of barrels of oil the world uses in just one year would circle the equator 650 times. Oil supplies about a third of the world's energy and its demand is increasing. Some experts argue that we can keep up with this increasing demand. They suggest we will discover new oil deposits and have improved drilling technologies that will help us access more oil. Others point out that for every barrel of new oil discovered, three to four barrels are consumed. The world consumed nine times more oil than the oil industry discovered from 2000 to 2005. Fossil fuels provide the energy necessary for much of the world's economies. Read on to see how these fuels are formed, where they exist, the size of the supply for each, and some of the arguments for and against future use of fossil fuel resources

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The carbon cycle describes how carbon moves between air, water, and land on Earth. Carbon is recycled throughout Eart h and all of its living organisms. Like the water cycle, the carbon cycle really has no beginning or end; it is simply a cycling of carbon through various materials.

In your own words, explain how burning fossil fuels in a power plant leads to electricity generation.

The fuel is first burned to heat water and produce steam. The steam then turns a turbine. The turbine turns magnets enclosed in copper wires within the generator. This creates electrical current, which can then flow out of the power plant and be transmitted to your home.

What makes the magnets in a generator spin and how does this result in the production of electric current?

The magnets are attached to the turbine and they spin in response to the spinning of the turbine. They are enclosed in copper wires. When magnets spin within a coil of copper wire, electric current is generated.

What is the world's largest business?

The oil industry is the world's largest business.

Section Warm-Up

The sources of oil in the United States are not always as straightforward as you may think. Political and economic factors often prompt the U.S. to look into ways of finding more oil sources in America, so that we do not have to rely on other countries. But there are only a few places in America where we can find the oil, which we burn for energy. One current possible source is the oil just off the coast of the American continent. We would have to drill off shore to get to this oil; this news clip will show you why this idea is so controversial.

What makes the turbine in a power plant spin?

The turbine spins when steam exerts a force on it, just like blowing on a pinwheel makes it spin.

The world's 3 biggest users of oil are

The world's three biggest users of oil are China, the U.S., and Japan

The Types of Coal

There are different types of coal based on how long and how far down the initial plant material is buried. Peat is partially decayed plant material and it accumulates when dead plant material exceeds the rate of the material's bacterial decay. It has very high moisture content. Lignite is also called brown coal. It is the youngest of all the coal types and has only 25 to 35 percent carbon. It is used almost exclusively for electric power plants, where it is burned to produce steam. It has a low energy yield and so is not usually transported internationally or even locally. Lignite is often used in power plants close to where it is mined. Lignite can have up to 66 percent moisture content, making it an inefficient, low-grade fuel source. Sub-bituminous coal is in a more advanced stage of development than lignite, and is 35 to 45 percent carbon. It has properties in between lignite and bituminous coal and is used primarily for electricity production. Bituminous coal is used extensively as a fuel source because it has a high energy yield. There are large supplies of it worldwide, so it is readily available for use. Bituminous coal has 45 to 86 percent carbon, and is commonly used as a source of electric power and in the steel industry. Anthracite is a very hard, glossy black coal. It has low moisture content and is highly desirable for fuel because of its high energy content. It has the highest carbon content (86 to 98 percent) and the fewest impurities of all coal types.

Solutions

To address the environmental and societal problems associated with fossil fuel use, we have come up with several possible solutions. One of these is to simply use less energy. Another is to rely more on non-fossil fuel sources of energy, such as hydro power, solar power, and wind power, all of which you learn about later in this unit. Another solution is to come up with technology that prevents some of the pollution associated with fossil fuels. For example, that billowing cloud of smoke that you see coming out of a power plant's smokestack is called flue gas. It contains carbon dioxide, sulfur and mercury pollutants. Flue gas can be treated to remove carbon dioxide and sulfur as it leaves the smokestack. One of these treatments is called a wet scrubber, which works by spraying flue gas with limestone and water to remove sulfur. Carbon dioxide can then be cooled and condensed to a liquid and buried deep underground for long-term storage. Currently, however, the technology required to remove carbon dioxide from coal on a large scale is too expensive to make it useful for most power plants. And the question of what to do with the carbon dioxide that gets removed from the emissions has not been answered. It does not go away; it just gets stored somewhere else.

Electricity Generation

Turn on your computer or flip on a light switch and you get electricity. Where does that electricity come from? Ultimately, it can be traced back to a power plant. If your local power plant uses any of the fossil fuels for electricity generation (and almost all of them do in the U.S.), then they do so by burning one of those fuels. This presentation goes over how burning a fossil fuel results in the generation of electricity. Watch the presentation for more information.

Our dependence on fossil fuels

What do you think could happen if there was a fossil fuel shortage? What if we could not get the oil we need to run our cars? What if we could not get the coal we need to power our power plants? What if we had no natural gas for cooking our food and heating our homes? Clearly fossil fuels play an important role in our society and our culture because they make working, playing, and surviving possible. Fossil fuels supply our electricity. Nearly half of the world's electricity comes from burning coal alone, though oil and natural gas also contribute their fair share. Fossil fuels make modern transportation possible. We mostly take it for granted that we can drive across the country and stop whenever we need to fill up our cars with gas. We also take it for granted that shipping trucks can do the same, in order to bring fresh vegetables to our grocery stores, shipments of new clothes to the malls, and packages from around the world. Fossil fuels are our leading source of power to heat and cool our homes. If you live in a cold climate, you know how good it feels to be able to switch the heat on in your home. Or maybe you live somewhere with sweltering summers and you appreciate being able to run the air conditioner. All of this is possible because of fossil fuels. So, what would a day without fossil fuels be like? Think about that for a minute.

In terms of energy conversions, what is the difference between a turbine and a generator?

When a turbine is acted on by the force of steam, the turbine begins to spin. This converts the heat energy of the steam to the mechanical energy of the moving turbine. A generator then converts mechanical energy to electrical energy

Fossil fuels come from the decay of plants. Since wood comes from trees, why is wood not considered one of the fossil fuels?

Wood is derived from trees that are still alive or that died only recently. To be a fossil fuel, the substance must be derived from the decay of organisms that died and were buried deep in Earth for hundreds of millions of years.

Fuels

You may have noticed that the cost of gasoline has fluctuated over the years. In fact, it reached an all-time high of over four dollars a gallon in 2008. Your car consumes this fuel to produce energy. Finding new sources of oil within the United States, or just off the coast, is an important part of reducing the cost of gasoline since most of the oil we use is purchased from other countries. Gas is not the only available fuel. Wood is also a fuel. You can burn wood to produce heat energy and to toast marshmallows around the campfire. Basically, a fuel is any substance that is consumed to produce energy. Another type of fuel is called a fossil fuel. Humans burn fossil fuels to produce the energy that powers our vehicles and provides electricity from electric power plants.

4. What is peat made of?

partially decayed plant material with high moisture content

1. In what types of rocks are coal deposits found?

sedimentary