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BI 105A Environmental Biology. Professor Jill Nissen Montgomery College Fall 2004. Chapter 10. Fossil Fuels. Objectives. p. 208, Questions #2-5, 7-8 Compare per-capita energy consumption in highly developed and developing countries
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BI 105AEnvironmental Biology Professor Jill Nissen Montgomery College Fall 2004
Chapter 10 Fossil Fuels
Objectives p. 208, Questions #2-5, 7-8 • Compare per-capita energy consumption in highly developed and developing countries • Describe the processes that formed coal, oil, and natural gas. • Discuss the advantages and disadvantages, including environmental problems, of using coal. • Discuss the advantages and disadvantages, including environmental problems, of using oil and natural gas. • Distinguish among the five kinds of synfuels and briefly consider the environmental implications of using synfuels. • Relate three reasons the U.S. needs a comprehensive national energy strategy. Briefly describe the National Energy Policy of the George W. Bush administration.
Energy use in highlydeveloped countries • Only 20% of the world’s population lives in highly developed countries • These people use 60% of the world’s commercial energy • Each person in highly developed countries uses 8 times as much energy as each person in a developing country!
Energy in U.S. • U.S. has 4.6% of world population; uses 24% of the world’s commercial energy; • 88% from nonrewable fossil fuels (65% oil & natural gas, 23% coal); • 7% from nuclear power; • 5% from renewable sources (hydropower, geothermal, solar, biomass).
Energy in U.S. • In 1973, 35% of the oil used in the U.S was imported • Today, U.S. imports 55.5% of its oil (12.9% from the Persian Gulf region) • The U.S Department of Energy estimates that by 2015, 100% of our oil will be imported
Changes in U.S. Energy Use Fig.19–4, p. 499
Coal formed from partially decomposed plant material exposed to heat and pressure for aeons
Sources & Uses • Most of the world's coal reserves are in the Northern Hemisphere, mainly the U.S.(25%), Russia, China, Australia, India, Germany, and South Africa. • Supplies 24% of world's commercial energy (23% in U.S.); • China largest user; U.S. second largest user.
Advantages and Disadvantages of Using Coal Advantages • most abundant fossil fuel; • major U.S. reserves, 200 yrs. at current consumption rates; • high net energy yield; Disadvantages • dirtiest fuel, highest carbon dioxide; • major environmental degradation; • major threat to health.
Oil and Natural Gas formed from large numbers of microscopic aquatic organisms that died and settled in oxygen-deficient sediments
Extraction & Processing Crude oil and natural gas are often trapped together Extraction: • primary - drill & pump • secondary - inject H2O • tertiary - inject steam or CO2 • refine to separate components based on different boiling components (Fig. 10-10) • transport by tanker, truck, pipeline
Oil • petroleum, or crude oil is acomplex liquid mixture of hundreds of hydrocarbon compounds, with small amounts of S, O, N impurities; • Supplies 61.5% of the energy used in the world (63% in U.S.);
Advantages and Disadvantages of Using Conventional Oil Advantages • low cost • high net energy yield • easily transported Disadvantages • Production is declining, and the supply will be depleted within 50–100 yrs • pollution & environmental degradation.
Natural Gas • mixture of only a few different hydrocarbons: mostly methane with smaller amounts of ethane, propane, and butane; • propane & butane are removed asliquefied petroleum gas (LPG) • Use of natural gas is increasing in 3 main areas – generation of electricity, transportation, and commercial cooling
Advantages and Disadvantages of Using Natural Gas Advantages • low cost; • reserves 65–80 yrs for U.S., 125 years for world at current consumption rates; • easy to transport by land via pipelines; Disadvantages • transport overseas difficult (LNG); • pollution & environmental degradation.
Oil in U.S. • Has 2.3% of world reserves, but • Uses nearly 30% of world reserves; • 65% for transportation; • increasing dependence on imports.
Sources • Organization of Petroleum Exporting Countries (OPEC) -- 13 countries have 65% world reserves: Algeria, Ecuador, Gabon, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, United Arab Emirates, & Venezuela • Almost half the recoverable reserves are in 2 countries, Russia and Iran
Synfuels Naturally occurring liquid or gaseous fuels that substitute for oil or natural gas • Tar sands, also known as oil sands • Oil shales • Gas hydrates, methane hydrates • Coal liquefaction • Coal gasification (Mini-glossary p. 226)
A National Energy Strategy Needed because: • The supply of fossil fuels is limited • The production, transport, and use of fossil fuels pollute the environment • Our heavy dependence on foreign oil makes us economically vulnerable
A National Energy Strategy Must have the following objectives: • Increase energy efficiency and conservation • Secure future fossil fuel energy supplies • Develop alternative energy sources • Accomplish the first three objectives without further damaging the environment
Current National Energy Policy Developed by President Bush (p. 230) 5 components: • Modernize conservation • Modernize energy infrastructure • Increase energy supplies • Accelerate the protection and improvement of the environment • Increase our nation’s energy security