energy resources and fossil fuels

Energy Resources and Fossil Fuels

Objectives:1.2.0 Evaluate various fossil fuels for their effectiveness as

energy resources.2.3.0 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:1. ?2. ?3. ?4. ?

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?1. Electric generator: a machine that converts

mechanical energy (motion) into electrical energy

2. Turbine: a wheel that changes the force of a moving gas or liquid into energy.

a. Heated water produces steam to turn the turbine.b. 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

A. World Patterns

B. Energy Use in the U.S.1. Only Canada and the United

Arab Emirates use more energy per person than the U.S.

2. Why do you think we use so much more than other countries?

3. 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.

Coal Petroleum Natural Gas

Formation

Uses

Environmental Effects

A. Coal Formation

1. From the remains of plants in swamps2. As ocean levels rose and fell, swamps were

layered with sediment, compressing plant remains.

3. Heat and pressure in the earth’s crust caused coal to form.

4. Most in eastern U.S. formed 250-300 million years ago under extreme heat and pressure

5. Most in western U.S. formed 40-100 million years ago

B. Oil and Natural Gas Formation1. Both form from the decay of tiny marine

organisms that accumulated on the bottom of the ocean millions of years ago.

2. Buried under sediment and heated until they became energy-rich carbon molecules

3. Found in porous rock formations• Why in AK, TX, CA, and Gulf of Mexico? Where

else worldwide?

V. Coal and the Environment1. Surface mining:

a. Sometimes removes entire mountains to expose the coal deposit

b. Toxic chemicals in waste rock can contaminate nearby water, if not contained properly

2. Air Pollutiona. Sulfur found in all coal enters air when burnedb. 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)

A.When burned, they release air pollutantsB.Oil spills pollute land and waterC.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

1. Popcorn reading: “Case Study” (pp.440-441)2. Answer questions on p.4413. Section Review (p.443): 2-4, 6