CHAPTER 17 Nonrenewable Energy Oil of Wilderness on

CHAPTER 17 Nonrenewable Energy

Oil of Wilderness on Alaska’s North Slope? • Oil has been extracted from parts of Alaska’s North Slope since 1977. • The Arctic National Wildlife Refuge (ANWR) contains oil deposits but oil exploration has been forbidden. • In 1980, a region called the 1002 Area was designated for future decision making. Today, a debate rages as to whether oil drilling should be allowed. Talk About It How might oil exploration in the 1002 Area affect the surrounding people and wilderness?

Lesson 17. 1 Energy: An Overview The United States has only 4. 5% of the world’s population but uses 21. 1% of the world’s energy.

Lesson 17. 1 Energy: An Overview What Is Energy? • The ability to do work or cause a change • Kinetic energy: Due to motion • Potential energy: Due to an object’s position or shape

Lesson 17. 1 Energy: An Overview Forms of Energy I • Mechanical: Associated with the motion and position of an object; can be kinetic or potential • Electrical: Associated with electric charges; can be kinetic or potential • Thermal: Kinetic energy of atoms and molecules— the faster atoms and molecules move in an object, the warmer it becomes Overhead transmission lines carry electrical current.

Lesson 17. 1 Energy: An Overview Forms of Energy II • Electromagnetic: Kinetic energy that travels as waves • Chemical: Potential energy stored in molecular bonds • Nuclear: Potential energy stored by forces that hold atomic nuclei together Chemical energy is stored in food.

Lesson 17. 1 Energy: An Overview Energy Conversion and Efficiency • Energy cannot be destroyed; it can only be converted, or changed, from one form to another. • Energy efficiency is an expression of how much of the energy put into a system actually does useful work. First Flight The combustion of gasoline powered the first airplane as it flew over the beach in Kitty Hawk, North Carolina, on December 17, 1903.

Lesson 17. 1 Energy: An Overview Energy Sources and Uses • Energy Sources • Renewable: Nearly always available or replaceable in a relatively short time; includes sunlight, wind, flowing water, heat from Earth • Nonrenewable: Cannot be replaced in a reasonable time; includes fossil fuels and nuclear energy • Energy Use • Four uses of energy: Industrial, transportation, residential, commercial • Developed nations tend to use more energy than developing nations. Wind power is a renewable energy source.

Lesson 17. 2 Fossil Fuels One quarter of global coal reserves are found in the United States.

Lesson 17. 2 Fossil Fuels • Include coal, oil, and natural gas • Formed from the remains of organisms over millions of years • Different conditions produce different fossil fuels A front loader piles coal at a steam station in Dunkirk, New York.

Lesson 17. 2 Fossil Fuels Coal • Formed from plant remains subjected to high heat and pressures over millions of years • Provides 1/4 of the world’s energy • Compared to other fossil fuels, coal is cheap, needs little processing, and is easy to transport. Did You Know? Coal is the most abundant fossil fuel on Earth. How Coal Forms

Lesson 17. 2 Fossil Fuels Coal Mining Strip mining: Overlying rock and soil are removed to access coal (safer for miners). Subsurface mining: Underground shafts are dug to access coal under Earth’s surface.

Lesson 17. 2 Fossil Fuels Oil • Dark, liquid fossil fuel made up mostly of hydrocarbons • Formed from the remains of ancient marine organisms and found in underground deposits • Used in fuel for cars, trucks, planes, ships • Used in chemical compounds (petrochemicals) • Also know as petroleum

Lesson 17. 2 Fossil Fuels Drilling and Refining Oil • After crude oil is extracted from the ground, it is separated into different fuels in a refinery. • Primary extraction: Oil flows out of the well, because it is already under pressure. • Secondary extraction: Increased pressure or injections needed to remove oil

Lesson 17. 2 Fossil Fuels Natural Gas • Primarily methane gas with small amounts of other gases mixed in • Often found above oil or coal deposits • Much less polluting than coal or oil and releases more energy when combusted • Used for heating, appliances (stoves, dryers), and making electricity

Lesson 17. 2 Fossil Fuels Fossil Fuel Supply • Consumption is still rising, but new fossil fuels do not form on a human timescale. • New oil sources—oil sands, oil shale, methane hydrates— are expensive, energy-intensive, and can be hazardous to obtain. • Coal sources are still relatively abundant, but not infinite. Did You Know? Some studies suggest we have extracted nearly half Earth’s oil, and that U. S. coal supplies may last just 130 years.

Lesson 17. 3 Consequences of Fossil Fuel Use The United States imports two thirds of its crude oil.

Lesson 17. 3 Consequences of Fossil Fuel Use Pollution, Climate Change, and Public Health • Burning fossil fuels releases carbon dioxide, which contributes to global climate change. • When coal and oil burn, sulfur dioxide and nitrogen oxides are released, which contribute to smog and acid deposition. • Oil spills, equipment ruptures, and oil in runoff pollute waterways, oceans, and coastal areas. • Coal-fired power plants release mercury, which harms human health. Crude oil contains trace amounts of lead and arsenic. Did You Know? Coal-burning power plants cause 40% of mercury emissions due to human activity in the United States.

Lesson 17. 3 Consequences of Fossil Fuel Use Gulf of Mexico Oil Well Explosions • 1979: Ixtoc I exploratory oil well • 50 m below surface • Released 126 million gal oil; containment efforts took 9 months • What didn’t work: cap, siphoning, controlled burn, “top kill” • What did work: relief wells • 2010: Deepwater Horizon oil well • 1500 m below surface • Largest U. S. offshore oil breach as of 2010— 21. 2 – 33. 5 million gal oil released during first 6 weeks, based on USGS rough estimates • Hundreds of miles of coastal habitats threatened • Methods tried: dome, cap, siphoning, controlled burns, “top kill, ” “junk shot, ” and relief wells Controlled burns attempt to contain oil pumping into the Gulf, one month after the 2010 well blow-out.

Lesson 17. 3 Consequences of Fossil Fuel Use Damage Caused by Extracting Fuels • Mining: • Humans risk lives and respiratory health. • Ecosystems are damaged by habitat destruction, extensive erosion, acid drainage, and heavy metal contamination downslope of mines. • Oil and gas extraction: • Roads and structures built to support drilling break up habitats and harm ecosystems. • The longterm consequences of accidents can be uncertain or unpredictable Acid drainage from a coal mine

Lesson 17. 3 Consequences of Fossil Fuel Use Dependence on Foreign Sources • Fossil fuels are not evenly distributed over the globe, so some countries must import fuel sources. • Nations that import fuel may be vulnerable to changes in fuel prices set by suppliers. • Nations can import less fuel by developing domestic oil sources and renewable energy sources.

Lesson 17. 3 Consequences of Fossil Fuel Use Energy Conservation • Practice of reducing energy use to make fossil fuels last and to prevent environmental damage • Transportation: Gas-efficient cars and higher gas prices could help conserve energy in the U. S. • Personal choices: Individuals can save energy by turning off lights, taking public transit, and buying energy-efficient appliances. Did You Know? Transportation accounts for 2/3 of U. S. oil consumption.

Lesson 17. 4 Nuclear Power Scientists estimate that nuclear power helps us avoid emitting 600 million metric tons of carbon each year worldwide.

Lesson 17. 4 Nuclear Power Nuclear Fission • Splits an atomic nucleus into two smaller nuclei • Releases neutrons and large amounts of energy. If enough unstable nuclei are present, a nuclear chain reaction can occur. Did You Know? About 20% of electricity produced in the United States comes from nuclear power.

Lesson 17. 4 Nuclear Power Generating Electricity Using Nuclear Energy

Lesson 17. 4 Nuclear Power Benefits and Costs of Nuclear Power Benefits Costs No air pollution Expensive to build and maintain Requires little uranium fuel and little mining Catastrophic accidents are possible. Under normal conditions, nuclear power plants are safer for workers than coal-burning power plants. Nuclear waste must be stored for thousands of years. Chernobyl

Lesson 17. 4 Nuclear Power Nuclear Waste • Waste is currently held at power plants as a stopgap, but a long-term storage location is needed. • Long-term storage sites must be distant from population centers, protected from sabotage, have a deep water table, and be geologically stable. • Yucca Mountain, Nevada, was chosen by the U. S. government in the 1980 s, and a storage site was constructed there. But, as of 2010, the Yucca Mountain project is no longer under development. Yucca Mountain storage site

Lesson 17. 4 Nuclear Power Nuclear Fusion • Joining two atomic nuclei to form one nucleus • Releases much more energy than fission • Currently impractical because very high temperatures are needed, but scientists continue exploring fusion for our future energy needs