Download Chapter 26 - Lake Fenton Community Schools

Conventional Energy Resources
Objectives
• Recognize the Sun as the ultimate source of most
energy on Earth.
• Describe how energy changes from one form to another.
• Identify materials that are used as fuels.
• Explain how fossil fuels form.
Vocabulary
– fuel
– peat
– fossil fuel
Conventional Energy Resources
Transfer of Solar Energy
• The energy that humans and all other organisms
use comes mostly from the Sun.
• Green plants, protists such as algae, and
cyanobacteria are producers that capture the
Sun’s energy in the process of photosynthesis.
• Trapped solar energy is transferred through the
food chains when consumers eat producers.
• A food chain is a model that shows how solar
energy flows from the Sun to producers and
then to consumers in an ecosystem.
Conventional Energy Resources
Transfer of Solar Energy
• Traditional sources of energy, such as wood,
peat, and fossil fuels, are derived from
producers such as plants.
• The energy stored in organic materials is
released when they are burned.
Conventional Energy Resources
Traditional Sources of Energy
• Humans have been able to survive in cold
climates primarily because of their ability to alter
the environment to meet their needs.
• Fuels are materials that are burned to produce
heat or power.
• Humans have burned wood to cook their food for
many thousands of years.
• Traditional fuels include renewable resources
such as wood, dried field crops, and dried fecal
material from animals such as cows and bison.
Conventional Energy Resources
Traditional Sources of Energy
• The total amount of living things in an ecosystem
is its biomass.
• Biomass fuels, which are fuels derived from
living things, are widely used in many developing
countries.
• Wood is the most commonly used traditional
biomass fuel.
Conventional Energy Resources
Traditional Sources of Energy
Wood
– Humans have been using wood as an energy source
for thousands of years.
• People living in developing countries use half of the
world’s wood supply as their primary source of fuel,
which has led to deforestation in many areas.
• In industrialized countries, trees are cut down for
lumber and paper production rather than fuel.
Conventional Energy Resources
Traditional Sources of Energy
Field Crops
– Humans use other materials, including field crops, as
fuel when wood is scarce.
• The simplest way to use field crops is to burn
them directly.
• Crop residues left after harvest are other sources of
energy. All of these can be burned to provide heat.
Conventional Energy Resources
Traditional Sources of Energy
Fecal Material
– Feces are the solid wastes of animals.
– In many cases, dried feces contain undigested pieces of
grass that help the material to burn.
– Fecal material from cows often meets the energy needs
of people in developing countries that have limited
forest resources.
Conventional Energy Resources
Traditional Sources of Energy
Peat
– Bogs are poorly drained areas with spongy, wet
ground that is composed mainly of dead and decaying
plant matter.
– Plants in bogs including Sphagnum moss, which forms
large mats on top of the water, accumulate as they die.
– Peat is a light, spongy material that is formed when
dead plant material is compressed in a bog.
– Highly decomposed peat burns with greater fuel
efficiency than wood and is still used to heat homes in
Ireland, England, parts of northern Europe, and the
United States.
Conventional Energy Resources
Fossil Fuels
• Fossil fuels are energy sources that formed
over geologic time as a result of the
compression and partial decomposition of plants
and other organic matter.
• Fossil fuels are considered to be nonrenewable
because their formation occurred over thousands
or even millions of years.
• Fossil fuels include peat, coal, natural gas, and
petroleum.
Conventional Energy Resources
Fossil Fuels
• The high concentration of carbon and hydrogen
in fossil fuels makes them very efficient
energy sources.
• All fossil fuels originated from organic matter
trapped in sedimentary rock.
Conventional Energy Resources
Fossil Fuels
Coal
– Coal formed from compressed organic matter at the
bottom of ancient swamps in which the carbon
concentration increased as oxygen and hydrogen
were lost.
– Coal can be classified according to carbon concentration
which is determined by the amount of pressure under
which it formed and the amount of time involved.
– The higher the carbon concentration, the hotter and
cleaner the coal burns.
Conventional Energy Resources
Fossil Fuels
Coal
– Lignite is a soft, brown, low-grade coal that forms from
peat and has carbon concentrations of around
40 percent.
– Bituminous coal is the most distributed coal in the
United States and has carbon concentrations as high
as 85 percent.
– Anthracite is the most efficient and most cleanly burning
coal with carbon concentrations of 90 to 95 percent.
– Bituminous coal is the most widely used coal in the
United States although carbon and sulfur and nitrogen
oxides are released into the air when it burns.
Conventional Energy Resources
Fossil Fuels
Petroleum and Natural Gas
– Petroleum refers to the natural crude oil found
underground and on Earth’s surface.
– Crude oil is a mixture of compounds of hydrogen and
carbon called hydrocarbons, which can be burned to
release energy.
– Oil originated organically as organisms died and fell to
the oxygen-poor environment at the bottom of the seas
where they were compressed into sedimentary rocks.
– Bacteria that do not require oxygen partially
decomposed the accumulated organisms and released
methane, which is one of the components of natural gas.
Conventional Energy Resources
Fossil Fuels
Migration
– Crude oil and natural gas migrate sideways and upward
from their place of formation through the pores of
permeable sedimentary rocks.
– Oil and gas continue to rise until they reach a barrier of
impermeable rock, such as slate or shale, that prevents
their continued upward movement.
– Geologic formations such as faults and anticlines can
trap petroleum deposits.
Conventional Energy Resources
Fossil Fuels
Migration
Conventional Energy Resources
Section Assessment
1. Match the following terms with their definitions.
___
B fuel
___
A peat
___
C fossil fuel
___
D anthracite
A. a fuel that is cut from bogs and
dried in the sun
B. materials that are burned to
produce heat or power
C. energy sources formed over
geologic time as a result of the
compression and partial
decomposition of organic matter
D. the cleanest-burning type of coal
Conventional Energy Resources
Section Assessment
2. What is biomass fuel?
Biomass fuel is any fuel derived from living things.
Conventional Energy Resources
Section Assessment
3. Identify whether the following statements are
true or false.
______
false Coal is a biomass fuel.
______
true Bituminous coal is the most widely available
coal in the United States.
______
true Highly decomposed peat burns with greater
fuel efficiency than wood.
______
true The stored energy in petroleum originally came
from the Sun.
Alternative Energy Resources
Objectives
• Identify alternative energy resources.
• Compare the advantages and disadvantages of the
various alternative energy resources.
Vocabulary
– photovoltaic cell
– geothermal energy
– biogas
– gasohol
Alternative Energy Resources
Alternative Energy Resources
• Most people rely on nonrenewable fossil fuels
for their energy needs which are being used up
at an alarming rate.
• Some experts estimate that petroleum resources
may be used up within the next 60 years.
• Renewable alternatives to traditional energy
resources include solar energy, wind, water,
geothermal energy, nuclear energy, and biomass.
Alternative Energy Resources
Solar Energy
• The Sun is the ultimate source of most energy
on Earth.
• The main advantages of solar energy are that it is
free and it doesn’t cause any kind of pollution.
Alternative Energy Resources
Solar Energy
Passive Solar Heating
– The Sun can heat up the inside of a car or a building
just by shining through the windows.
– The Sun’s energy also can be captured to be released
during the evening in floors and walls made of
concrete, adobe, brick, stone, or tile, which have heatstoring capacities.
– Passive solar designs can provide up to 70 percent of
the energy needed to heat a house, as well as up to 60
percent of the energy needed to cool it.
Alternative Energy Resources
Solar Energy
Passive Solar Heating
Alternative Energy Resources
Solar Energy
Active Solar Heating
– Active solar-heating systems include collectors such as
solar panels that absorb solar energy and fans or
pumps that distribute that energy throughout the house.
– Heat collected by the solar panels can be used to heat
a house directly, or it can be stored for later use in
insulated tanks that contain rocks, water, or a heatabsorbing chemical.
Alternative Energy Resources
Solar Energy
Solar Cookers
– Solar cookers can be used effectively where fuels are
scarce or expensive, as in countries that have cut
down most of their forests.
– A solar cooker can be as simple as an enclosed box
with reflectors to direct the Sun’s rays inside the box.
Alternative Energy Resources
Solar Energy
Photovoltaic Cells
– An economical and practical method of storing large
amounts of direct solar energy for long periods of time
has not yet been developed.
– Photovoltaic cells, which are thin, transparent wafers
made up of layers of boron- and phosphorus-enriched
silicon, convert solar energy into electrical energy.
– The electricity produced by photovoltaic cells can be
stored in batteries.
– It is estimated that power towers may someday supply
30 percent of the electric power used worldwide.
Alternative Energy Resources
Energy from Water
• Hydroelectric power is energy produced by water
moving through turbines that drive generators.
• Hydroelectric power currently provides about 20
percent of the world’s electricity and 6 percent of
its total energy.
• One advantage of hydroelectric power is that it
is nonpolluting.
• Dams built to harness hydroelectric power have
negative impacts including flooding large areas,
destroying wildlife habitats, and changing the
natural pattern of water flow.
Alternative Energy Resources
Energy from Water
Energy from the Oceans
– The kinetic energy in waves, which is created primarily
by wind, can be used to generate electricity.
– Barriers built across estuaries or inlets can capture the
energy associated with the ebb and flow of tides for
use in tidal power plants.
– While power from moving ocean water is renewable
and nonpolluting, barriers in the ocean can change the
water level and may disrupt coastal and marine
ecosystems.
Alternative Energy Resources
Geothermal Energy
• Geothermal energy is energy produced by
steam and hot water generated by Earth’s own
internal heat.
• Abundant at some surface locations usually
coinciding with plate boundaries, geothermal
energy can be harnessed to heat homes and
businesses and generate electricity.
• If developed, geothermal reservoirs in the United
States could possibly provide up to 30 times as
much energy as the country currently uses.
Alternative Energy Resources
Geothermal Energy
Advantages and Disadvantages
of Geothermal Energy
– Geothermal energy is abundant and reliable at the
sites where it occurs but must be managed carefully.
– Water heated by geothermal energy frequently
contains large amounts of minerals that can clog
pipes and pollute surface water.
– Geothermal energy is useful only near sites where it
exists, because transporting it is not practical.
Alternative Energy Resources
Wind Energy
• The wind turbines on a wind farm convert the
energy of the wind to mechanical energy, which is
then used to produce electrical energy.
• Wind energy increases with the cube of the
wind speed.
• Most of the wind farms in the United States are
currently in California, although North Dakota,
South Dakota, and Texas have the best locations.
• Wind power could supply more than 10 percent
of the world’s electricity by the year 2050.
Alternative Energy Resources
Wind Energy
Advantages and Disadvantages of Wind Energy
– Wind is a virtually unlimited energy resource at
favorable sites worldwide.
– Wind farms are nonpolluting and can be built quickly
and expanded as needed.
– Wind energy is one of the least expensive ways to
produce electricity, but it is economical only in areas
with steady winds.
– Wind farms are not very attractive and they have been
shown to interfere with and even kill migrating birds, as
well as birds of prey.
Alternative Energy Resources
Nuclear Energy
• During nuclear fission, a large amount of energy is
released when a heavy nucleus (mass number
greater than 200) divides to form smaller nuclei
and one or two neutrons.
• Uranium is a radioactive element that is commonly
used in the production of nuclear energy.
• Nuclear power plants do not produce carbon
dioxide or any other greenhouse gases.
• After 50 years, 424 nuclear reactors in 25
countries currently are producing only 17 percent
of the world’s electricity.
Alternative Energy Resources
Nuclear Energy
• No new nuclear plants have been built in the
United States since 1978.
– Poor management, high operating costs, poor reactor
designs, and public concerns about safety and disposal
of radioactive wastes contributed to the decline of
nuclear power.
– In addition, nuclear accidents such as those at
Three Mile Island and at Chernobyl, Ukraine, in 1986,
alerted people worldwide about the hazards of
nuclear power plants.
Alternative Energy Resources
Biomass
• Biomass is a renewable energy resource as long
as the organisms that provide the biomass are
replaced.
• Bacteria and chemical processes can be used to
convert solid biomass into gaseous and liquid
biofuels, such as biogas, liquid ethanol, and
liquid methanol.
• A disadvantage of biomass fuels is that when they
are burned, they release carbon dioxide and
particulate matter into the atmosphere.
Alternative Energy Resources
Biomass
Biogas
– Biogas is a mixture of gases that includes 50 to 70
percent methane gas and 30 to 48 percent carbondioxide gas.
– Plant and animal wastes can be converted into
methane gas in simple containers, called digesters,
by the action of bacteria.
– In the digesters, gas is separated from the solid wastes
and piped into homes for use as a cooking fuel.
Alternative Energy Resources
Biomass
Ethanol and Methanol
– Liquid ethanol is another name for grain alcohol that can
be made from sugar and grain crops including sugar
cane, sugar beets, sorghum, and corn.
– Gasohol is gasoline mixed with ethanol produced from
corn, which can be burned more cleanly than pure
gasoline in conventional gasoline engines.
– Liquid methanol, which is wood alcohol, is made mostly
from natural gas, but it can also be made from wood,
wood wastes, agricultural wastes, sewage sludge,
garbage, or coal.
Alternative Energy Resources
Energy from Oil Shale and Tar Sand
• Oil shale is a fine-grained rock that contains a
solid, waxy mixture of hydrocarbon compounds
called kerogen.
• When oil shale is heated, the kerogen vaporizes
and can be condensed to form a heavy, slowflowing, dark-brown oil known as shale oil.
• At present, the cost of processing oil shale is
higher than the cost of traditional crude oil.
Alternative Energy Resources
Energy from Oil Shale and Tar Sand
• Tar sand is a mixture of clay, sand, water, and
bitumen, which is a heavy, black, high-sulfur oil.
• When heated, the bitumen fluid softens and floats
to the top where it can be collected and upgraded
into a type of crude oil.
• The processing of oil shale and tar sand requires
large amounts of energy and produces air and
water pollution.
Alternative Energy Resources
Section Assessment
1. Match the following terms with their definitions.
___
D photovoltaic cell
___
B geothermal
energy
___
A biogas
___
C gasohol
A. a mixture of gases produced in a
digester that includes 50 to 70
percent methane gas and 30 to
48 percent carbon-dioxide gas
B. energy produced by naturally
occurring steam and hot water
C. a mixture of gasoline and ethanol
that can be burned in
conventional gasoline engines
D. thin, transparent wafers that
convert solar energy into
electrical energy
Alternative Energy Resources
Section Assessment
2. How would you store large amounts of solar
energy for long periods of time?
To store solar energy for long periods of time
you would need to convert direct solar energy
into electrical energy which can be stored in
batteries.
Alternative Energy Resources
Section Assessment
3. Identify whether the following statements are
true or false.
______
false Hydroelectric power represents about
20 percent of the electricity in the United States.
______
true No greenhouse gases are released from nuclear
power plants.
______
false Shale oil is profitable to extract and refine.
______
true Burning biomass fuel produces approximately
10 percent of Hawaii’s electrical supply.
Conservation of Energy Resources
Objectives
• Recognize the need for the conservation of
energy resources.
• Identify ways to conserve energy resources.
Vocabulary
– energy efficiency
– cogeneration
– sustainable energy
Conservation of Energy Resources
Conservation of Energy Resources
• Although fossil fuels are nonrenewable and in
limited supply, industrialized countries continue to
consume these resources at ever increasing rates.
Conservation of Energy Resources
Conservation of Energy Resources
• The best way to meet energy needs is a
combination of improved energy efficiency and
increased use of locally available, renewable
energy resources.
Conservation of Energy Resources
Energy Efficiency
• Energy efficiency is the use of energy resources
in the ways that are most productive.
• Using resources more efficiently is a type of
conservation.
Conservation of Energy Resources
Energy Efficiency
• How can energy efficiency be improved?
– People can recycle old appliances and vehicles and
purchase newer, more energy-efficient models as well as
improve the energy efficiency of older homes.
– Local power companies can use energy from alternative
resources in areas where they are available to reduce
dependence on petroleum.
– Governments can offer tax savings to people who buy
more efficient vehicles and appliances, and provide
funding for research and development projects related
to energy efficiency.
Conservation of Energy Resources
Energy Efficiency
Conservation of Energy Resources
– There are many ways that you could conserve energy
at home, at school, and in the workplace, such as
simply turning lights off when you leave a room.
– Conserving energy is, in the long run, less expensive
than finding new energy sources.
Conservation of Energy Resources
Getting More for Less
• Higher energy demand requires a greater supply
and results in higher costs.
• In the United States, approximately 43 percent of
the energy used by motor vehicles and to heat
homes and businesses is wasted.
• Shifting to the more efficient use of energy rather
than the search for more energy would reduce
demand, thus lowering the total cost of energy.
Conservation of Energy Resources
Getting More for Less
Cogeneration
– Waste heat, which could be recovered and used to
produce another form of energy, is given off when
power plants generate electricity.
– Cogeneration is the production of two usable forms of
energy, such as steam and electricity, at the same time
from the same process.
– Cogeneration can produce income and reduce the
need for additional energy resources.
Conservation of Energy Resources
Getting More for Less
Improving Efficiency in Transportation
– Conservation practices can help reduce dependency
on the fuel resources used for transportation.
• The use of fuel-efficient vehicles and driving at lower
speeds reduces the amount of petroleum resources
consumed by motor vehicles.
• Using bicycles, public transportation, or carpooling
reduces the number of vehicles on the roads which
in turn reduces gasoline consumption.
• Computers and access to the Internet allow more
jobs to be performed from home.
Conservation of Energy Resources
Getting More for Less
Improving Efficiency in Industry
– Cogeneration has allowed some industries to increase
production while leveling off their energy use in part by
the use of more efficient machinery.
– Industries can further improve their energy efficiency
by making greater efforts to reduce their use of
both materials and the energy used to produce
those materials.
Conservation of Energy Resources
Getting More for Less
Increasing Efficiency at Home
– The use of energy-efficient appliances can significantly
reduce energy consumption.
– The use of building materials and windows with high
insulation values (R-values) can significantly reduce
energy consumption.
– Incorporating passive and active solar heating in new
buildings can reduce the consumption of traditional
energy resources.
– New buildings that are designed to save energy cost
more initially, but they can save money and resources
in the long run.
Conservation of Energy Resources
Sustainable Energy
• Energy resources on Earth are interrelated,
meaning that they affect one another.
• Sustainable energy involves the global
management of Earth’s natural resources to meet
current and future energy needs without causing
environmental damage.
• A good management plan incorporates both
conservation and energy efficiency.
• Global cooperation can help ensure the necessary
balance between protection of the environment
and economic growth.
Conservation of Energy Resources
Section Assessment
1. Match the following terms with their definitions.
___
A energy
efficiency
A. the use of energy in ways that are
most productive
___
C cogeneration
B. global management of Earth’s
natural resources to meet current
and future energy needs without
causing environmental damage
___
D R-value
___
B sustainable
energy
C. the production of two usable forms
of energy at the same time from
the same process
D. a rating that indicates the
insulation abilities of building
materials
Conservation of Energy Resources
Section Assessment
2. How does the use of renewable resources as a
percentage of energy consumption in developing
countries compare to industrialized countries?
A larger percentage (42 percent) of the energy
used in developing countries comes from
renewable resources compared to industrialized
countries (10 percent). Most of the difference can
be attributed to the higher use of biomass as a
percentage of the total among developing
countries (35 percent) compared to industrialized
countries (3 percent).
Conservation of Energy Resources
Section Assessment
3. Identify whether the following statements are
true or false.
______
false It is better to depend upon a single energy
source that has been reliable in the past.
______
false An insulation rated at R-13 has a higher
insulation value than insulation rated at R-19.
______
false It is more energy efficient to drive at higher
speeds because your trip takes less time.
______
true Cogeneration has allowed some industries
to increase production while leveling off
energy use.
Chapter Resources Menu
Study Guide
Section 26.1
Section 26.2
Section 26.3
Chapter Assessment
Image Bank
Section 26.1 Study Guide
Section 26.1 Main Ideas
• The Sun is the ultimate source of most energy on Earth.
The Sun’s energy is transferred from photosynthetic
organisms to all other living things.
• Materials derived from living things, known as biomass,
have been used as renewable fuels by humans for
thousands of years.
• Wood continues to serve as a fuel for over half of the
world’s population.
• Fossil fuels, such as natural gas, coal, and petroleum,
formed from organisms that lived millions of years ago.
The burning of these fossil fuels releases sulfur into the
atmosphere, and thus contributes to air pollution.
Section 26.2 Study Guide
Section 26.2 Main Ideas
• Alternative energy resources, such as solar energy, water,
geothermal energy, wind, nuclear energy, and biomass,
can supplement dwindling conventional energy resources.
• Solar energy is unlimited, but technological advances are
needed to find practical solutions to collect and store it.
• Hydroelectric power is derived from the energy of moving
water and is commonly used in the production of
electricity. Geothermal energy is a product of Earth’s
internal heat. Its usefulness is limited to areas where it is
found near Earth’s surface. Wind is a source of energy in
areas that have consistently strong winds.
Section 26.2 Study Guide
Section 26.2 Main Ideas
• Nuclear energy results when atoms of radioactive
elements emit particles in the process known as fission.
• Oil shale and tar sand contain secondary oil resources
that are expensive to extract.
Section 26.3 Study Guide
Section 26.3 Main Ideas
• Energy resources will last longer if conservation and
energy efficiency measures are developed and used.
Energy efficiency results in the use of fewer resources to
provide more usable energy.
• Cogeneration, in which two usable forms of energy are
produced at the same time from the same process,
saves resources in the long run.
• The achievement of sustainable energy use will ensure
that current and future energy needs are met while
maintaining standards of living and at the same time
protecting the environment.
Chapter Assessment
Multiple Choice
1. Which type of coal is the most efficient and
cleanest burning?
a. anthracite
c. peat
b. lignite
d. bituminous
Peat, if continued to be compressed, becomes lignite
which has carbon concentrations around 40 percent.
Bituminous coal, the most abundant coal in the United
States, has carbon concentrations as high as 85
percent. Anthracite has carbon concentrations as high
as 95 percent. The higher the carbon concentration, the
hotter and cleaner the coal burns.
Chapter Assessment
Multiple Choice
2. Which of the following is a traditional
energy source?
a. wind energy
c. solar energy
b. geothermal energy
d. biomass fuels
Wind, geothermal, and solar energy are all renewable
alternative energy sources. Biomass fuels, including
wood, field crops, fecal matter, and peat, are traditional
energy sources.
Chapter Assessment
Multiple Choice
3. What percentage of the industrialized countries’
energy use is from oil?
a. 23 percent
c. 44 percent
b. 37 percent
d. 50 percent
In industrialized countries, more energy comes from oil
than any other source. In developing countries, biomass
is the leading source of energy at 35 percent.
Chapter Assessment
Multiple Choice
4. Which of the following states has the best
conditions for a wind farm?
a. North Dakota
c. Texas
b. South Dakota
d. all of the above
Nearly all of the energy needs of the country could be
met if wind farms were built in just these three states
which experience constant, steady winds.
Chapter Assessment
Multiple Choice
5. When was the last nuclear plant built in the
United States?
a. 1978
c. 1988
b. 1984
d. 1994
Poor management, high operating costs, poor reactor
designs, and public concerns about safety and disposal
of radioactive wastes contributed to the decline of nuclear
power. An accident at the nuclear plant at Three Mile
Island near Harrisburg, Pennsylvania in 1979 further
sealed the fate of nuclear power in the United States.
Chapter Assessment
Short Answer
6. Why isn’t oil shale widely used as a source
of oil?
Oil shale is not widely used as a source of oil
because the cost of processing oil shale is
higher than the cost of crude oil sold by
countries that have abundant oil supplies.
Chapter Assessment
Short Answer
7. What is an active solar-heating system?
An active solar-heating system includes
collectors, such as solar panels, that absorb
solar energy and fans or pumps that
distribute that energy throughout the house.
Chapter Assessment
True or False
8. Identify whether the following statements are
true or false.
______
true Almost everything you eat contains trapped
solar energy.
______
true The search for crude oil often begins in areas
with thick layers of sedimentary rock.
______
false Passive solar designs can only provide up to 40
percent of the energy needed to heat a house.
______
false Roughly 2.5 billion people throughout the world
use wood as their primary energy source.
______
true In China, approximately 300 million bicycles
are in use.
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Chapter 26 Images
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Chapter 26 Images
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