Geology And Global Energy Resources Environmental Sciences
Energy can be generally classified as non-renewable and renewable. Over 85% of the energy used in the world is from non-renewable supplies which is the focus of this assignment. Energy is used for transportation, manufacturing, electricity generation, heating and cooking. Most developed nations are dependent on non-renewable energy sources such as fossil fuels and nuclear power. These sources are called non-renewable because they cannot be renewed or regenerated quickly enough to keep pace with their use. Some sources of energy are renewable, e.g. solar, geothermal, hydroelectric, biomass, and wind. Industrialized nations depend on non-renewable energy sources.
In 19th century, the industrial revolution in Europe evoked the man's search for alternative sources of fuel to meet energy needs of the growing industries. Fossil fuels fulfilled these needs for the time being. Fossil fuels are called so because they have been derived from fossils. When plants and other ancient creatures died, they decomposed and were buried, layer upon layer under the ground. It took millions of years to form these layers into a hard, black rock-like substance called coal, a thick liquid called oil or petroleum, and natural gas -the three major forms of fossil fuels:
A soft, black solid that can be scratched with a fingernail. It is made up of carbon, hydrogen, oxygen, nitrogen and varying amounts of sulfur. Coal formed slowly over millions of years from the buried remains of ancient swamp plants. During the formation of coal, a compressed spongy material called "peat" formed first which contained 90% water. As the peat became more deeply buried, the increased pressure and temperature turned it into coal (Fig. 1).
Figure 1: Coal was formed from the remains of ancient plants.
Different types of coal resulted from differences in the pressure and temperature that prevailed during formation. The softest coal (about 50% carbon), which also has the lowest energy output, is called lignite. Lignite has the highest water content (about 50%) and relatively low amounts of smog-causing sulfur. With increasing temperature and pressure, lignite is transformed into bituminous coal (about 85% carbon and 3% water). Anthracite (almost 100% carbon) is the hardest coal and also produces the greatest energy when burned. Most of the coal found in the United States is bituminous. Unfortunately, bituminous coal has the highest sulfur content of all the coal types. When the coal is burned, the pollutant sulfur dioxide is released into the atmosphere.
Coal mining creates several environmental problems. Coal is most cheaply mined from near-surface deposits using strip mining techniques. Strip-mining causes considerable environmental damage in the forms of erosion and habitat destruction. Sub-surface mining of coal is less damaging to the surface environment, but is much more hazardous for the miners due to tunnel collapses and gas explosions.
Coal is the most abundant fossil fuel in the world with an estimated reserve of one trillion metric tons. Most of the world's coal reserves exist in Eastern Europe, Asia and United States. Currently, the world is consuming coal at a rate of about 5 billion metric tons per year. The main use of coal is for power generation, because it is a relatively inexpensive way to produce power. Over 50% of the electricity in the United States is produced by Coal. In addition to electricity production, coal is sometimes used for heating and cooking in less developed countries and in rural areas of developed countries. If consumption continues at the same rate, the current reserves will last for more than 200 years.
The burning of coal results in significant atmospheric pollution. The sulfur contained in coal forms sulfur dioxide when burned, contributing to acid rain. Harmful nitrogen oxides, heavy metals, and carbon dioxide are also released into the air during coal burning. The toxic ash remaining after coal burning is also an environmental concern and is usually disposed into landfills.(ii) Oil:
All living things are made of complex molecules of long strings of carbon atoms. Connected to these carbon atoms are others such as hydrogen and oxygen (Fig. 2). Crude oil or liquid petroleum is a soft and sticky black stuff that contains many different molecules, but all are made of carbon and hydrogen atoms. Oil forms underground in rock such as shale, which is rich in organic materials. After the oil forms, it migrates upward into porous reservoir rock such as sandstone or limestone, where it can become
Figure 2: Organic materials are formed from chains of carbon atoms.
trapped by an overlying impermeable cap rock. Wells are drilled into these oil reservoirs to take out the oil and gas (Fig. 6). Over 70 percent of oil fields are found near tectonic plate boundaries, because the conditions there are favorable for oil formation.
Oil recovery can involve more than one stage. About 25 percent of the oil in a reservoir can be recovered during primary stage which involves pumping oil from reservoirs under the normal reservoir pressure. The secondary recovery stage involves injecting hot water into the reservoir around the well. This water forces the remaining oil toward the area of the well from where it can be recovered. Sometimes a tertiary recovery technique is used in order to draw as much oil as possible. This involves pumping steam, carbon dioxide gas or nitrogen gas into the reservoir to force the remaining oil toward the well. Tertiary recovery is very expensive and can cost up to half of the value of oil recovered. Carbon dioxide used in this method remains attached in the deep reservoir, thus mitigating its potential greenhouse effect on the atmosphere (Fig. 3).
Figure 3: Oil recovery.
Oil is stored in large tanks until it is sent to various places to be used. At oil refineries, the process required to convert crude oil into useable hydrocarbon compounds involves boiling this thick black crude to split it into various types of products. The products include gasoline, diesel fuel, aviation or jet fuel, home heating oil, oil for ships and oil to burn in power plants to make electricity. Besides its use as a source of energy, oil also provides base material for plastics, provides asphalt for roads and is a source of industrial chemicals. Here's what a barrel of crude oil can make (Fig. 4).
Most known oil reserves are already being exploited, and oil is being used at a rate that exceeds the rate of discovery of new sources. Over 50 percent of the world's oil is found in the Middle East; sizeable additional reserves occur in North America. If the consumption rate continues to increase and no significant new sources are found, oil supplies may be exhausted in another 30 years or so. Despite its limited supply, oil is a relatively inexpensive fuel source. It is a preferred fuel source over coal. An equivalent amount of oil produces more kilowatts of energy than coal. It also burns cleaner, producing about 50 percent less sulfur dioxide, it, however, does cause environmental
Figure 4: Source: American Petroleum Institute (www.api.org). Figures are based on 1995 average yields for U.S. refineries. One barrel contains 42 gallons of crude oil.
problems. The burning of oil releases atmospheric pollutants such as sulfur dioxide, nitrogen oxides, carbon dioxide and carbon monoxide. These gases pollute the atmosphere and contribute to global warming. Substantial oil reserves lie under the ocean. Oil spill accidents involving drilling platforms kill marine organisms and birds. The building of roads, structures and pipelines to support oil recovery operations can severely impact the wildlife in those natural areas.(iii) Natural Gas:
Natural gas production is often a by-product of oil recovery, as the two commonly share underground reservoirs (Fig. 6). Natural gas is a mixture of gases, the most common being methane (CH4) (Fig. 5). It also contains some ethane (C2H5), propane (C3H8), butane (C4H10). Natural gas is usually not contaminated with sulfur and is therefore the cleanest burning fossil fuel. After recovery, propane and butane are
Figure 5: Methane (CH4)
removed from the natural gas and made into liquefied petroleum gas (LPG). LPG is shipped in special pressurized tanks as a fuel source for areas not directly served by natural gas pipelines. The remaining natural gas is further refined to remove impurities and water vapor and then transported in pressurized pipelines. Natural gas is highly flammable and is odorless; therefore a smelly sulfur compound is added during its refining to warn consumers of gas leaks.
Most of the world's natural gas reserves are found in Eastern Europe and the Middle East. Its use is growing rapidly. Besides being a clean burning fuel source, natural gas is easy and inexpensive to transport once pipelines are in place. In developed countries, natural gas is used primarily for heating, cooking, and powering vehicles. It is also used in a process for making ammonia fertilizer. The current estimate of natural gas reserves is about 100 million metric tons. At current usage levels, this supply will last an estimated 100 years.
Figure 6: Pockets of oil and natural gas may become trapped between layers of non-porous rocks.(iv) Oil Shale and Tar Sands:
Oil shale and tar sands are the least utilized fossil fuel sources. Oil shale is sedimentary rock with very fine pores that contain a waxy substance known as kerogen. If shale is heated to 490° C, the kerogen vaporizes and can then be condensed as shale oil, a thick viscous liquid. This shale oil is generally further refined into usable oil products. Production of shale oil requires large amounts of energy for mining and processing the shale. Indeed about a half barrel of oil is required to extract every barrel of shale oil. Oil shale is plentiful, with estimated reserves totaling 3 trillion barrels of recoverable shale oil. These reserves alone could satisfy the world's oil needs for about 100 years. Environmental problems associated with oil shale recovery include: large amounts of water needed for processing, disposal of toxic waste water, and disruption of large areas of surface lands.
Tar sand is a type of sedimentary rock that is saturated with a very thick crude oil. This thick crude does not flow easily and thus normal oil recovery methods cannot be used to mine it. Tar sands can be mined directly if they are near the surface. Extraction from deep-seated tar sands, however, steam must be injected into the reservoir to make the oil flow better and push it toward the recovery well. The energy cost for producing a barrel of tar sand is similar to that for oil shale. The largest tar-sand deposit in the world is in Canada and contains enough material (about 500 billion barrels) to supply the world with oil for about 15 years. However, because of environmental concerns and high production costs these tar sand fields are not being fully utilized.Nuclear Power
Nuclear fuel makes use of the radioactivity of some elements. The nucleus in the atom may spontaneously break down to release energy and produce fast-moving particles, atoms of other elements. In a nuclear power plant, the fission of uranium atoms in the reactor provides the heat to produce steam for generating electricity. Heat is produced in a nuclear reactor when neutrons strike uranium atoms, causing them to split in a continuous chain reaction. Control rods, which are made of a material such as boron that absorbs neutrons, are placed among the fuel assemblies. When the neutron-absorbing control rods are pulled out of the core, more neutrons become available for fission and the chain reaction speeds up, producing more heat. When rods are inserted into the core, fewer neutrons are available for fission, and the chain reaction slows or stops, reducing the heat generated. Heat is removed from the reactor core area by water flowing through it. The heat is transferred to a second water loop through a heat exchanger. The water also serves to slow down the neutrons, which is necessary for sustaining the fission reactions. The second loop is kept at a lower pressure, allowing the water to boil and create steam, which is used to power the turbine-generator and produce electricity.
Nuclear fission does not produce atmospheric pollution or greenhouse gases, so it was expected that nuclear energy would be a clean, cheap and last longer than fossil fuels. But unfortunately, because of construction cost overruns, poor management etc, nuclear power ended up being much more expensive than predicted. The nuclear accidents at Three Mile Island in Pennsylvania and the Chernobyl Nuclear Plant in the Ukraine raised concerns about the safety of nuclear power. Furthermore, the problem of safely disposing spent nuclear fuel remains unresolved.Environmental Impacts and the Cost of Fossil Fuels:
Several years ago, people were concerned that the earth's supply of coal and oil would be exhausted because of the continuously increasing world population and of the growing demand of developing countries for more fuel. This standpoint, however, has completely changed in this present time. The people's attention has dramatically shifted to saving the environment from the various forms of pollution caused by the continued use of fossil fuels. Today, the real pressing concern is: Even before the earth's supply of fossil fuels is completely used up, save the environment from being totally destroyed by pollution caused by the uninterrupted use of fossil fuels.
In his article "An Economy for the Earth" in the May/June 2002 issue of the Humanist, Lester Brown makes the important point that a "deteriorating environment will eventually hurt the economy," stressing the need for an environmentally sustainable economy. The fossil-fuel-based energy path that the industrial nations have stepped for so long isn't the boon that its advocates--especially in the United States--currently claim. Even in purely financial terms, its cost to the economy outweighs its benefit when a full accounting is performed. Worse yet, in light of what we now know, the disease and death it causes can--without exaggeration--be called criminal. Staying on the present path means that we'll continue the devastating impact on health while accepting the growing environmental disaster of a kind unprecedented in human history. There's a grim synergy here: global warming will increase disease. "It's not only going to be a warmer world, it's going to be a sicker world," says Andrew Dobson, an epidemiologist at Princeton University and co-author of a recent study from the National Center for Ecological Analysis and Synthesis. An acceptable new path requires a humanistic energy program informed by science rather than greed, which serves human needs nationally and internationally (Huebner, 2003).
Fossil fuels are one of the greatest threats to the environment today. Burning any fossil fuel means pollution of some sort. At present, the worldwide burning of coal, oil, and natural gas releases billions of tonnes of carbon dioxide into the atmosphere every year. Even if the fossil fuel is low in sulphur, the atmosphere contains nitrogen, which combines with oxygen at the high burning temperatures found in boilers, jet, or car engines, yields nitrogen oxides, which like sulphur dioxide, dissolves in rain to form nitric acid. Both gases are poisonous to humans.
Their burning contributes heavily to global warming, the pollution of the air, water and land, as well as the production of acid rain. When fossil fuels are burned, huge amounts of carbon are released into the air. This contributes to the greenhouse effect, causing the sun's heat to be excessively trapped in the atmosphere rising global temperature. Melting of the polar ice caps causes ocean levels to rise as well. This reduces the salinity of the ocean, endangering many organisms that are dependent upon a certain level of salt concentration to be able to live. It also poses a serious risk of many cities and settlements located close to sea level entirely disappearing under water. Mining and exploration for fossil fuels can cause disturbance to the surrounding ecosystem.Literature Review
IEA: Fossil energy to dominate market through 2030 by Doris Leblond.Introduction:
Fossil fuels will continue to dominate the energy system in 2030, despite reduced oil production rates. Projecting current growth rates forward, the two major renewable energy sources - wind and solar - will still only contribute a fraction of the energy from present coal production, alone.
Fossil fuels currently comprise more than eighty percent (80%) of the world's primary energy production (Fig. 7).
Figure 7: World primary energy production 2005 (EIA). Uses the most recent data available from the U.S. Department of Energy's Energy Information Agency (EIA).
According to the International Energy Agency's World Energy Outlook 2006, fossil fuels will dominate the energy market through 2030. The report says that the reliance on fossil fuel prevails both in a reference scenario as well alternative policy scenario. In the reference scenario, oil demand would grow by 1.3%/year during 2005-2030. The main demand for oil to 2030 will be from the transport sector. Over 70% of the oil demand increase will come from developing countries. The share of natural gas also rises, but grows less than projected in the last Outlook due to higher prices. Organization of Petroleum Exporting Countries share of global supply grows to 48% by 2030 from 40%.Sources of demand:
The share of developing nations in this hike is 70% being economically fast growing countries. Oil demand rises more slowly in developed countries, Organization for Economic Cooperation and Development member countries, especially in Europe and the Pacific region but its worth mentioning that North America is the largest oil consumer and an absolute increase of 5.9 million b/d has been noted over the Outlook period. The share of natural gas also rises, but grows less than anticipated in the last Outlook due to higher prices. However, gas demand grows faster than coal, which sees the biggest fossil fuel demand increase but it does not overtake it before 2030.
Coal - by far the dirtiest of the fossil fuels, mainly used for generating electricity - also has a wide range of future production estimates. The EIA recently estimated global reserves at about 140 years at current usage rates, with production rising by more than half over the next two decades.
Transport sector will be the major utilizer of oil to 2030, which rose to 47% in 2004 from 35% in 1980. It is projected to increase to 52% in 2030. Although bio-fuels are expected to make a significant contribution to meeting the sector's needs, their share by 2030 will reach only 4%. However, report points out that new biofuels technology, could allow bio-fuels to play a significant role.Petroleum Supply Sources:
"All the easy oil and gas in the world has pretty much been found. Now comes the harder work in finding and producing oil from more challenging environments and work areas."
- William J. Cummings, Exxon-Mobil company spokesman, December 2005
"It is pretty clear that there is not much chance of finding any significant quantity of new cheap oil. Any new or unconventional oil is going to be expensive."
- Lord Ron Oxburgh, a former chairman of Shell, October 2008
Oil supply is greatly dominated by a small number of major producers where oil resources are concentrated. Organization of Petroleum Exporting Countries share of global supply grows to 48% by 2030 from 40% now and 42% in 2015. Conventional oil production from non-OPEC will be declining from 2010 and the rate, but natural gas liquids production continues to grow. This leaves an increasing importance for non-conventional oil in total production and implying higher real oil prices. According to the Outlook, there are sufficient oil resources in place for the period up to 2030, provided that sufficient investments are made and that new technologies for improved oil recovery (IOR) or enhanced oil recovery (EOR) are available. Conventional oil accounts for the big share of the increased oil supply over the Outlook period where as non conventional resources-mainly oil sands in Canada and to a lesser extent, gas-to-liquids plants play a growing role. Canadian oil sands are projected to triple to 3 million b/d by 2015 and reach 5 million b/d by 2030. Heavy oils of Venezuela are also of greater importance.
The oil industry needs to invest $ 164 billion/year over 2005-30. Three quarters of this will go to the upstream but IEA does not guarantee that all investment needed will be available due to the certain constraints, which include possible impact of government policies, geopolitical factors, unexpected changes in unit costs, and prices and new technology could affect the opportunities and incentives for private and publicly owned companies to invest. IEA is particularly uncertain about the ability and willingness of major oil and gas producer countries to step up investment in order to meet rising global demand. Although the capital spending by the world's leading oil and gas companies increased sharply over the first half of the current decade and will rise further to 2010 but the rising cost may affect this trend.Prices:
The trend in the price of oil is harder to predict. Volatility in oil prices can be induced by the impact of severe weather conditions on offshore supplies, industrial strife impacting on short-term supplies, the threat of terrorist strikes against oil infrastructure, and political uncertainties in producing regions like the Middle East, Russia, Central Asia, Venezuela and Africa. As the crude oil and refined-product market remains tight over the Outlook period, IEA has revised the oil prices upwards in the expectation. Market may tend to show a decline in prices as new capacity comes on stream and demand growth slows down but prices could be driven up by new geopolitical tensions or a major supply disruption.
The Outlook assumes that the average IEA crude oil import price-$51/bbl in 2005-will average slightly over $60/bbl through 2007, then decline to $47/bbl by 2012. It would rise slowly thereafter, reaching $50/bbl in 2020 and $55 in 2030. Assuming a 2.3%/year inflation rate, the price in nominal terms would reach $97/bbl in 2030. Natural gas prices should follow this trend because of inter-fuel competition and the continuing use of oil-price indexation in long-term gas supply contracts.
Oil demand in global oil consumption becomes insensitive to shifts in international crude prices; implying prices would fluctuate more than in the past to future short-term demand and supply shifts. However, it is careful to add: "oil prices still matter to the world economy," which would have grown more rapidly had oil prices and other energy prices not increased, the impact being higher on heavily indebted poor countries.Sources / References:
Montgomery, C.W, (2008), Environmental Geology, Eighth Edition.
Tarbuck, E. J. and Lutgens F.K, (1999), Earth -An introduction to Physical Geology, Sixth Edition.
Plummer, C.C, (2005), Physical Geology, Tenth Edition.
Leblond, D, 2006, IEA: Fossil energy to dominate market through 2030, Oil & Gas Journal. Tulsa: Nov 20, 2006. Vol. 104, Iss. 43; pg. 28, 2 pgs.
Huebner, A.L, 2003, The Cost of Fossil Fuels, Humanist; Mar/Apr 2003, Vol. 63 Issue 2, p7, 3p
Deal, W.F, 2006, Resources in Technology-Energy Perspectives: Another look at fossil fuels, The Technology Teacher, May/June 2006, pg. 10-14.
Nanji, N, and Klippenstein, M, 2009, The Energy System of 2030-Towards an Electron Democracy, McKinsey & Company, management consultants, under the title "Electron-democracy". Available in McKinsey's What Matters online publication at: http://whatmatters.mckinseydigital.com/energy.
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