Chapter 5
Energy Resources
I. Natural Resources
A. Earth’s Resources
• The resources that the Earth provides for
you are called natural resources
- the Earth’s atmosphere provides air
and produces rain
- the Earth’s crust gives nutrients, such
as potassium, to the plants you eat
- other examples are water, petroleum,
minerals, forests, and animals
• The energy we get from these
resources ultimately comes from the
sun’s energy
B. Renewable Resources
• A natural resource that can be replaced at
the same rate at which it is used
- trees are fresh water are examples of
renewable resources
C. Nonrenewable Resources
• A resource that forms at a rate that is much
slower than the rate at which it is
consumed
- coal takes millions of years to form and
once it is used up, it is no longer available
- petroleum and natural gas are other
examples
D. Conserving natural resources
1. Energy conservation
• If we don’t limit our use of
nonrenewable resources now, the
resources may not be available in the
future
• You can conserve resources by being
careful to use only the resources that
you need
2. Reduce, Reuse, Recycle
• Recycling is the process of
reusing materials form
waste or scrap
• Recycling reduces the
amount of natural resources
that must be obtained from
the Earth
• Recycling also conserves
energy
II. Fossil Fuels
A. Energy Resources
• Natural resources that humans use to
generate energy
• Most of the energy we used comes from
a group of natural resources called fossil
fuels
• Fossil fuels are nonrenewable energy
resources formed from the remains of plants
and animals that lived millions of years ago
- examples are petroleum, coal, and natural
gas
• Energy is released from fossil fuels when they
are burned
B. Types of fossil fuels
• All living things are made up of the element
carbon
• Fossil fuels are therefore made of carbon
too because they are formed from the
remains of living things
1. Liquid Fossil Fuels: Petroleum
• Commonly known as crude oil
• Petroleum is separated into several kinds of
products by a processed called distillation
- products made from petroleum include
gasoline, jet fuel, kerosene, diesel fuel,
and fuel oil
2. Gaseous fossil fuels: natural gas
• Used for heating and generating electricity
• Some motor vehicles used natural gas as
fuel
• Methane, CH4, is the main component of
natural gas
3. Solid fossil fuels: coal
• Coal was once the major source of energy
in the U.S.
• As cleaner energy resources became
available, people reduced their use of coal
• Many power plants still use coal to
generate electrical energy
III. How do fossil fuels form?
A. Petroleum and natural gas formation
• Form mainly from the remains of
microscopic sea organisms
• These remains are buried in sediment on
the ocean floor
• The sediment is compacted and slowly
becomes rock
• Under pressure of overlying rocks, the
fossil fuels can move through permeable
rocks
• Permeable rocks become reservoirs that
hold petroleum and natural gas
http://www.youtube.com/watch?v=XoyqQgmwY9E&feature=related
B. Coal Formation
• Coal forms
underground over
millions of years when
pressure and heat
cause changes in the
remains of swamp
plants
1. Swamp plants that
have not decayed
change into peat,
brown, crumbly
matter that is 60%
carbon
Peat
2. When peat is buried
by sediment, pressure
and temperature
increase and turn peat
into a type of coal
called lignite that is
70% Carbon
Peat
Lignite
3. As the pressure and heat force water and
gases out of the lignite, it changes into
bituminous coal that is 80% carbon
Peat
Lignite
Bituminous
4. Upon increased pressure and temperature,
bituminous coal changes into anthracite that is
90% carbon
• The greater the carbon content of the coal,
the more cleanly the coal burns
Peat
Lignite
Bituminous
Anthracite
IV. How do we obtain fossil fuels
• Petroleum and natural gas are removed
from Earth by drilling wells into rock that
contains these resources
http://www.youtube.com/watch?v=xUBP-jQvi8M&feature=channel&list=UL
• Coal is obtained by either mining deep
beneath Earth’s surface or by surface mining
V. Problems with fossil fuels
A. Coal mining
• Surface mining removes soil, which some
plants need for growth and some
animals need for shelter
• Underground mines have the potential
of collapsing and endangering the lives
of miners
B. Petroleum problems
• The toxic oil can cause environmental
problems and endanger wildlife when
spilled
C. Smog
• Smog is photochemical haze that forms
when sunlight acts on industrial pollutants
and burning fuels
VI. Alternative resources
A. Splitting the atom: fission
• Fission is a process in which the nuclei of
radioactive atoms are split into two or
more smaller nuclei
• When fission takes place, a large amount
of energy is released
• The energy released is nuclear energy
• This energy can be used to generate
electrical energy
1. Pros
• Alternative source of energy that does not
have the problems that fossil fuels do
2. Cons
• Nuclear power plants
produce dangerous
radioactive wastes
• Radioactive wastes
must be stored until
their radioactivity
decreases to a harmless
level
• Nuclear wastes can
remain dangerously
radioactive for
thousands of years
B. Combining atoms: fusion
• Fusion is the joining of two or more nuclei
to form a larger nucleus
• This process releases a large amount of
nuclear energy
• Fusion happens naturally in the sun
1. Pros
• Produces few dangerous wastes
2. Cons
• Very high temperatures are required for
the process to take place
• No known material can withstand such
high temperatures
C. Chemical energy
• Chemical energy is the energy released
when a chemical compound reacts to
produce new compounds
• Fuel cells convert chemical energy into
electrical energy by reacting hydrogen and
oxygen into water
D. Solar Energy
• Solar energy is the energy received by the
Earth from the sun in the form of radiation
• Sunlight can be changed into electrical
energy through the use of solar cells
1. Solar heating
• Solar energy is used for
direct heating through
solar collectors
• Solar collectors are darkcolored boxes that have
glass or plastic tops
2. Pros and Cons of solar energy
• Solar energy does not produce pollution
• Solar energy is renewable because it comes
from the sun
• Solar cells and solar collectors are
expensive
http://www.youtube.com/watch?v=NDZzAIcCQLQ
E. Wind Power
• Wind is made
indirectly by solar
energy through the
uneven heating of
air
• Wind power is the
use of a windmill
to drive an
electrical generator
http://www.youtube.com/watch?v=tsZITSeQFR0
F. Hydroelectric energy
• Electrical energy produced
by falling water
1. Pros and cons of
hydroelectric energy
• Inexpensive and causes
little pollution
• Not available
everywhere
• Disrupts migratory paths
of fish populations
• Creates erosion
problems
http://www.youtube.com/watch?v=cEL7yc8R42k&feature=related
G. Power from plants
• Biomass is organic matter that can be a
source of energy
• Plants are sources of biomass because they
absorb energy from the sun and store it for
later use
1. Burning Biomass
• Energy contained in biomass can be
released by burning of it
• About half of the world’s population burn
wood or charcoal to heat their homes and
cook
H. Geothermal energy
• The energy produced by the heat within
Earth
• Groundwater is sometimes heated by
magma and is released as steam through
vents, called geysers, above ground
• Geothermal power plants can harness
energy from within Earth by drilling wells
into the rock