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Energy Resources and Fossil Fuels. Objectives: 2.0 Evaluate various fossil fuels for their effectiveness as energy resources. 3.0 Evaluate other sources of energy for their effectiveness as alternatives to fossil fuels. . Discussion.
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Energy Resources and Fossil Fuels Objectives: 2.0 Evaluate various fossil fuels for their effectiveness as energy resources. 3.0 Evaluate other sources of energy for their effectiveness as alternatives to fossil fuels.
Discussion • What is the difference between renewable energy and nonrenewable energy? • Give examples of each. • Which type do you think is used most worldwide? • Do you think there is a difference in the types of energy used by developed and developing countries?
Fossil fuels: • Def: the remains of ancient organisms that changed into coal, oil, or natural gas
I. Fuels for Different Uses • Used for 4 main purposes: • ? • ? • ? • ?
II. Electricity – Power on Demand • Advantages: • Travels long distances in short time • Convenient • Disadvantages: • Difficult to store • Has to be generated from other sources
A. How is Electricity Generated? • Electric generator: a machine that converts mechanical energy (motion) into electrical energy • Turbine:a wheel that changes the force of a moving gas or liquid into energy. • Heated water produces steam to turn the turbine. • The turbine spins a generator to produce electricity.
Most power plants only convert 33-40% of the energy in fossil fuels into electricity. Where does the rest of the energy go?
III. Energy Use • World Patterns
B. Energy Use in the U.S. • Only Canada and the United Arab Emirates use more energy per person than the U.S. • Why do you think we use so much more than other countries? • What do you think is the largest use of energy in the U.S.?
IV. How Fossil-Fuel Deposits Form Uneven distribution is due to the geological histories of the regions.
A. Coal Formation • From the remains of plants in swamps • As ocean levels rose and fell, swamps were layered with sediment, compressing plant remains. • Heat and pressure in the earth’s crust caused coal to form.
Most in eastern U.S. formed 250-300 million years ago under extreme heat and pressure • Most in western U.S. formed 40-100 million years ago
B. Oil and Natural Gas Formation • Both form from the decay of tiny marine organisms that accumulated on the bottom of the ocean millions of years ago. • Buried under sediment and heated until they became energy-rich carbon molecules • Found in porous rock formations • Why in AK, TX, CA, and Gulf of Mexico? Where else worldwide?
V. Coal and the Environment • Surface mining: • Sometimes removes entire mountains to expose the coal deposit • Toxic chemicals in waste rock can contaminate nearby water, if not contained properly • Air Pollution • Sulfur found in all coal enters air when burned • Higher grade coal burns cleaner and produces more heat
VI. Environmental Effects of Petroleum • Def: oil that is pumped from the ground (AKA, crude oil) • When burned, they release air pollutants • Oil spills pollute land and water • Natural gas is found along with oil, and burns much cleaner than other fossil fuels.
VII. Fossil Fuels and the Future • Fossil fuels supply about 90% of energy used in developed countries. • As demand increases and supplies dwindle, what happens to price? • What can we do to make sure we don’t run out? • Alternative energy sources • Deep-ocean oil reserves
Assignment • Popcorn reading: “Case Study” (pp.440-441) • Answer questions on p.441 • Section Review (p.443): 2-4, 6