Warm Up 10/13
1. Which of the following lists presents forms of coal in the
correct order from the first stage of development to the
last stage of development?
a. peat, lignite, anthracite, bituminous
b. anthracite, bituminous, lignite, peat
c. peat, lignite, bituminous, anthracite
d. bituminous, anthracite, peat, lignite
2. Vein deposits are usually produced by ____.
a. hydrothermal solutions
c. weathering
b. cementation and compaction d. density sorting
3. Which of the following is an example of a nonrenewable
resource?
a. cotton
c. uranium
b. cattle
d. trees
Answers: 1) c. 2) a. 3) c.
Alternate Energy Sources
Chapter 4, Section 2
Solar Energy
• Every second, the total energy Earth receives from
the sun amounts to more than 10,000 times the
total energy used by all human societies in a day
• Solar energy technologies use the sun’s rays to
supply heat or electricity
• Solar energy has two advantages: The “fuel” is
free, and it’s non-polluting
• There are a few drawbacks to solar energy: the
necessary equipment and installation is not free,
and a supplemental heating unit is needed for the
times when the sun is not out
• Research is currently underway to improve the
technologies for collecting sunlight
Solar Energy
Solar One outside Barstow, California
Concept Check
• What are the two main advantages to using
solar energy?
• The fuel is free and it is non-polluting!
Nuclear Energy
• Nuclear power meets about 7% of the energy
demand of the U.S.
• The fuel for nuclear plants comes from radioactive
materials that release energy through nuclear fission
• In nuclear fission, the nuclei of heavy atoms such as
uranium-235 are bombarded with neutrons; the
uranium nuclei then split into smaller nuclei and
emit neutrons and heat energy
• The neutrons that are emitted then bombard the
nuclei of adjacent uranium atoms, producing a chain
reaction
• The heat energy drives steam turbines that turn
electrical generators
Nuclear Energy
Fuel Pool
San Onofre Nuclear Plant,
California
Concept Check
• What is nuclear fission?
• The splitting of an unstable nucleus of an
atom into smaller parts, releasing large
amounts of energy
Wind Energy
• Wind is not a new energy source, we have
been using it for centuries to power sailing
ships and windmills for grinding grain
• In the year 2000, wind supplied a little less
than one percent of California’s electricity
• Some experts estimate that in the next 50 to
60 years, wind power could meet between 5
to 10 percent of the country’s demand for
electricity
• The need for technical advances, noise
pollution, and the cost of large tracts of land
in populated areas are obstacles to
development
Wind Energy
Wind Turbines outside Palm Springs, California
Hydroelectric Power
• Like wind, moving water has been an energy source
for centuries
• Hydroelectric Power – the power generated by
falling water
• In the U.S., hydroelectric power plants produce
about 5 percent of the country’s electricity
• The water held in a reservoir behind a dam is a form
of stored energy that can be released through the
dam to produce electric power
• Eventually rivers deposit sediment in the reservoir to
a point where the dam can no longer produce
electricity; this process takes approximately 50 to
300 years, depending on the amount of material the
river carries
Hydroelectric Power
Glen Canyon Dam and Lake Powell, Arizona and Utah Border
Geothermal Energy
• Geothermal Energy – the energy that can be
extracted from Earth’s internal heat, for example,
natural steam used for power generation
• Hot water is used directly for heating and to turn
turbines to generate electric power
• The reservoirs of steam and hot water occur where
subsurface temperatures are high due to relatively
recent volcanic activity
• Geothermal power is clean but not inexhaustible,
with the steam and hot water from individual wells
usually lasting no more than 10 to 15 years
Geothermal Energy
The Geysers north of Santa Rosa, California
Concept Check
• In what two ways is geothermal energy
used?
• Directly for heating and to turn turbines to
generate electricity
Tidal Power
• Tidal power is harnessed by constructing a
dam across the mouth of a bay or an estuary
in coastal areas with a large tidal range
• The strong in-an-out flow that results drives
turbines and electric generators
• Tidal power development isn’t economical if
the tidal range is less than eight meters or if
a narrow, enclosed bay isn’t available
• Tides will never produce a high portion of the
world’s energy needs, but it is an important
source at certain sites
Tidal Power
Assignment
• Read Ch. 4, Sect. 2 (pg. 102-107)
• Do Section 4.2 Assessment #1-6 (pg. 107)