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Energy
Non-renewable and Renewable Resources
The Earth’s Interior
• Composed of 4 layers
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Crust
Mantle
Outer Core
Inner Core
Crust
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Temperature: Over 175 degrees Celsius
Topmost layer of the Earth
Relatively cool
Made of rock
2 types of crust
• Oceanic (4-7 km thick)
• Continental (20-40 km thick)
Mantle
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Temperature: Over 1250 degrees Celsius
Makes up about 80% of the Earth’s volume
~ 2900 km thick
Outer mantle – rocks
Inner mantle – “plastic”
Core
• Temperature: Over 6000 degrees Celsius
• Outer core – liquid
• Pressure from the mantle & crust do not allow the metals in the
outer core to become gasses
• Inner core – solid
• Pressure from the mantle and crust do not allow the metals to
become liquid
Plate Tectonics
• The Earth’s lithosphere is made up of 7 tectonic plates
• Plate tectonics – the movement of these lithospheric plates
Why do the plates move?
• One theory suggests that plates move due to the
convection currents in the asthenosphere
(“plastic” inner portion of the mantle)
Divergent Plate Boundaries
• 2 plates move apart
• Magma fills the gap created from this movement
• Magma cools as it reaches the Earth’s surface creating rift
valleys
Convergent Plate Boundaries
• Oceanic plates dive beneath continental or oceanic plates
(called subduction)
• Creates deep ocean trenches
Wall diving- coral reefs form over
time on the “walls” of deep sea
trenches. Many are thousands of
feet deep.
Convergent Plate Boundaries
• Mountains form at the convergent plate boundaries as magma
from the mantle rises, pushing continental crust upward
Convergent Plate Boundaries
• Volcanoes form at the convergent plate boundaries as magma
rises to the surface and cools
Transform Fault Boundaries
• Plates move past each other at cracks in the lithosphere
(called faults)
• Transform fault boundary – horizontal movement between
two plates
Earthquakes
• Occur at plate boundaries
• Plates slide past each other creating pressure
• Rocks break along the fault line
• Energy is released, called seismic waves
San Andreas Fault
Focus = point of earthquake origination
Epicenter = point on the Earth’s surface
directly above the focus
Energy from an earthquake
• Energy is released in the forms of waves
• P wave: Primary or longitudinal waves
originate from the focus & move quickly
through rock. These are the first waves to be
recorded
• S wave: Secondary or transverse waves
originate from the focus & moves more slowly
through rock.
• Surface waves: move across the earth’s
surface, causes building to collapse
Earthquake Measurement
• Seismograph
• Records data about P, S and surface waves
• Used to locate the epicenter of an earthquake
• Richter scale
• Measures energy released at the epicenter of
an earthquake (in magnitude)
• Each step up in magnitude represents a 30-fold
increase in energy released!
Volcanoes
• Volcanoes result from openings or vents in the
Earth’s surface
• Magma reaches the surface through these vents
• When magma reaches the surface it changes
physically and is called lava
Shield Volcano
• Formed from fluid lava, rich in iron
• Shield volcanoes are large
Mauna Loa in Hawaii
Composite Volcano
• Made of alternating layers of lava, ash and
cinders.
• Magma is rich in silica and thick
• Large with steep slopes
Cinder Cone
• Large amounts of gas are trapped in the magma
causing violent eruptions
• Active for short periods of time
Minerals & Rocks
• Minerals:
• naturally occurring, inorganic substances
• (inorganic = does not contain Carbon)
• can be expressed by a chemical formula
• Quartz SiO2 (silicon dioxide)
• Rocks:
• Composed of minerals
Types of Rock
• Igneous
• Formed when magma or lava cools and hardens
• Magma forms intrusive igneous rock
• Lava forms extrusive igneous rock
• Sedimentary
• Formed when rock particles, plant and animal
debris are carried away by water, redeposited,
then fused together
• Metamorphic
• Rock particles are fused together by pressure beneath
the Earth’s surface
Determining the age of rocks
Two ways to “determine” the age of a rock:
1. Superposition – determine the age based on
layers, older rocks are on the bottom, newer
ones on top
2. Radioactive dating
The Rock Cycle
Weathering and Erosion
• Two types of weathering
• Physical
• Breaks rocks into smaller pieces, chemical
composition does not change
• May be caused by ice or plants
• Chemical
• Changes the chemical composition of rocks
• May be caused by oxidation or acid rain
Erosion
• Erosion: the process of loosening and removing
sediment
• Caused by water, glaciers, wind
Deposition
• Occurs when loose sediment is laid down
• Causes river beds to widen and deltas to form.
Important Elements
• Oxygen – most abundant element in the
Earth’s crust
• Nitrogen – most abundant element in the
atmosphere
• Iron – most abundant element in the core
Non-renewable Resources
• Defined:
• An energy source that cannot be renewed in our
lifetime
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Examples:
Oil
Natural Gas
Coal
Aluminum
Gold
Uranium
Non-renewable resources –
Environmental Impacts
• Mining
• IMPACTS:
• Disrupts land
• Disrupts ecosystems
• Causes acid rain
Surface Mining
• Description – if resource is <200 ft. from the
surface, the topsoil is removed (and saved),
explosives are used to break up the rocks and to
remove the resource, reclamation follows
• Benefits – cheap, easy, efficient
• Costs – tears up the land (temporarily),
byproducts produce an acid that can accumulate
in rivers and lakes
Underground Mining
• Underground Mining
• Description – digging a shaft down to the
resource, using machinery (and people) to tear
off and remove the resource
• Benefits – can get to resources far underground
• Costs – more expensive, more time-consuming,
more dangerous – mining accident in Chile
Coal
• formed from ancient peat bogs (swamps) that
were under pressure as they were covered.
• Used for electricity, heat, steel, exports, and
industry, may contribute to the “Greenhouse
Effect”
• Four types of coal exist: lignite (soft, used for
electricity), bituminous and subbituminous
(harder, also used for electricity) and anthracite
(hardest, used for heating)
• 50% of all the coal is in the United States, the
former Soviet Union and China
Increasing heat and carbon content
Increasing moisture content
Peat
(not a coal)
Lignite
(brown coal)
Bituminous
(soft coal)
Anthracite
(hard coal)
Heat
Heat
Heat
Pressure
Pressure
Pressure
Partially decayed
plant matter in
swamps and bogs;
low heat content
Low heat content;
low sulfur content;
limited supplies in
most areas
Extensively used as
a fuel because of its
high heat content
and large supplies;
normally has a high
sulfur content
Highly desirable
fuel because of
its high heat
content and low
sulfur content;
supplies are
limited in most
areas
Fig. 16-12, p. 368
Waste heat
Coal bunker
Cooling tower
transfers waste
heat to
atmosphere
Turbine
Generator
Cooling loop
Stack
Pulverizing
mill
Condenser
Filter
Boiler
Toxic ash disposal
Fig. 16-13, p. 369
COAL
• Coal reserves in the United States, Russia, and China could last
hundreds to over a thousand years.
• The U.S. has 27% of the world’s proven coal reserves, followed
by Russia (17%), and China (13%).
• In 2005, China and the U.S. accounted for 53% of the global coal
consumption.
Reclamation
• returning the rock layer and the topsoil to a
surface mine, fertilizing and planting it
• Benefits – restores land to good condition
• Costs – expensive, time-consuming
• In the United States, mining companies are
required to do this!
Open-pit Mining
• Machines dig holes and
remove ores, sand,
gravel, and stone.
• Toxic groundwater can
accumulate at the
bottom.
Figure 15-11
Area Strip Mining
• Earth movers strips away
overburden, and giant
shovels removes mineral
deposit.
• Often leaves highly
erodible hills of rubble
called spoil banks.
Figure 15-12
Contour Strip Mining
• Used on hilly or
mountainous terrain.
• Unless the land is
restored, a wall of dirt is
left in front of a highly
erodible bank called a
highwall.
Figure 15-13
Mountaintop Removal
• Machinery removes the
tops of mountains to
expose coal.
• The resulting waste rock
and dirt are dumped into
the streams and valleys
below.
Figure 15-14
United States mining
• Central – diamonds (Arkansas), bituminous coal
• West – bituminous and subbituminous coal, gold,
silver, copper
• East – anthracite coal, bituminous coal
• South – some gold (SC), bituminous coal
• North – bituminous coal, some gold (SD, WI)
Energy from non-renewable
resources
• Cogeneration
• Primary
• Secondary
Fossil Fuels
• Only about 30% efficient
• Benefits –
• easy to use, currently abundant
• Costs –
• a nonrenewable resource, produces pollutants that
contribute to acid rain and the greenhouse effect
• Oil- Supplies the most commercial energy in the
world today. People in the U.S. use 23 barrels of
petroleum per person or 6 billion barrels total each
year!!!
Gases
Gasoline
Aviation fuel
Heating oil
Diesel
oil
Naptha
Heated
crude oil
Furnace
Grease
and wax
Asphalt
Fig. 16-5, p. 359
OIL
• Eleven OPEC (Organization of Petroleum
Exporting Countries) have 78% of the world’s
proven oil reserves and most of the world’s
unproven reserves.
• After global production peaks and begins a slow
decline, oil prices will rise and could threaten the
economies of countries that have not shifted to
new energy alternatives.
Case Study: U.S. Oil Supplies
• The U.S. – the world’s largest oil user – has only
2.9% of the world’s proven oil reserves.
• U.S oil production peaked in 1974 (halfway
production point).
• About 60% of U.S oil imports goes through
refineries in hurricane-prone regions of the Gulf
Coast.
Heavy Oils from Oil Sand and Oil Shale:
Will Sticky Black Gold Save Us?
• Heavy and tarlike oils from oil sand and oil shale
could supplement conventional oil, but there are
environmental problems.
• High sulfur content.
• Extracting and processing produces:
• Toxic sludge
• Uses and contaminates larges volumes of
water
• Requires large inputs of natural gas which
reduces net energy yield.
Oil Shales
• Oil shales contain a
solid combustible
mixture of
hydrocarbons called
kerogen.
Figure 16-9
Core Case Study:
How Long Will the Oil Party Last?
• We have three options:
• Look for more oil.
• Use or waste less oil.
• Use something else.
Figure 16-1
NATURAL GAS
• Natural gas, consisting mostly of methane, is
often found above reservoirs of crude oil.
• When a natural gas-field is tapped, gasses are
liquefied and removed as liquefied petroleum
gas (LPG).
• Coal beds and bubbles of methane trapped in ice
crystals deep under the arctic permafrost and
beneath deep-ocean sediments are
unconventional sources of natural gas.
NATURAL GAS
• Russia and Iran have almost half of the world’s
reserves of conventional gas, and global reserves
should last 62-125 years.
• Natural gas is versatile and clean-burning fuel,
but it releases the greenhouse gases carbon
dioxide (when burned) and methane (from leaks)
into the troposphere.
Nuclear
Economics
Energy Efficiency – Nonrenewable energy sources
• Coal, Natural Gas, Oil: about 30% efficient
• Nuclear:
Laws of Thermodynamics
• 1st law: Conservation of Energy
• Energy cannot be created nor destroyed
• Energy can be transferred from one system to another
• 2nd law:
• Energy transfer must only have one direction
• Entropy (disorder) increases over time
• 3rd law:
• Absolute zero is achieved when all kinetic energy stops
SO…..
• 1st law of Thermodynamics
• Explains how we can convert energy from chemical or
mechanical energy to usable electric energy
• windmill animation
• 2nd law of Thermodynamics explains WHY energy efficiency can
be so low
Renewable Energy
Solar
• Solar energy is harnessing energy from the sun’s
rays
• Passive Solar – Placing buildings strategically to
take advantage of the sun’s heat
• Example: Log Homes
• Active Solar – uses solar panels to convert
energy into a usable form such as electricity
Single solar cell
Solar-cell roof
–
+
Boron
enriched
silicon
Roof options
Junction
Phosphorus
enriched silicon
Panels of
solar cells
Solar
shingles
Fig. 17-17, p. 398
• Benefits of Solar:
• Readily available
• Renewable
• Fairly simple system
• Pollution free energy source
• Can sell back extra energy to the power company
• Drawbacks of Solar:
• High start up cost for active solar energy system
• Location dependent (Seattle would not be a good
city for solar energy)
Core Case Study: The Coming
Energy-Efficiency and RenewableEnergy Revolution
• It is possible to get electricity from solar cells
that convert sunlight into electricity.
• Can be attached like shingles on a roof.
• Can be applied to window glass as a
coating.
• Can be mounted on racks almost
anywhere.
Core Case Study: The Coming
Energy-Efficiency and RenewableEnergy Revolution
• The heating bill for this energy-efficient passive solar radiation
office in Colorado is $50 a year.
Figure 17-1
Passive Solar
Heating
• Passive solar heating
system absorbs and
stores heat from the sun
directly within a structure
without the need for
pumps to distribute the
heat.
Figure 17-13
Direct Gain
Ceiling and north wall
heavily insulated
Summer
sun
Hot air
Warm
air
Superinsulated
windows
Winter
sun
Cool air
Earth tubes
Fig. 17-13, p. 396
Greenhouse, Sunspace, or
Attached Solarium
Summer cooling vent
Warm air
Insulated
windows
Cool air
Fig. 17-13, p. 396
Earth Sheltered
Earth
Reinforced concrete,
carefully waterproofed
walls and roof
Triple-paned or
superwindows
Flagstone floor for heat
storage
Fig. 17-13, p. 396
Trade-Offs
Passive or Active Solar Heating
Advantages
Disadvantages
Energy is free
Need access to sun
60% of time
Net energy is
moderate
(active) to high
(passive)
Quick installation
No CO2 emissions
Sun blocked by
other structures
Need heat storage
system
Very low air and
water pollution
High cost (active)
Very low land
disturbance
(built into roof
or window)
Active system
needs maintenance
and repair
Moderate cost
(passive)
Active collectors
unattractive
Fig. 17-14, p. 396
Cooling Houses Naturally
• We can cool houses by:
• Superinsulating them.
• Taking advantages of breezes.
• Shading them.
• Having light colored or green roofs.
• Using geothermal cooling.
Wind
• Wind energy is converted into a usable energy form by using
wind turbines
www.lacoastpost.com
www.windenergyplanning.com
Wind Power
• Benefits of Wind Power:
• Readily available
• Can sell back extra power
• Pollution free energy source
• Drawbacks of Wind Power:
• Disrupts migration patterns
• Turbine farms are not aesthetically pleasing
• Turbines are expensive
• Good for specific locations only
Hydro
• Hydro power is mechanical energy derived from
water
• Most hydropower is generated by damming
rivers
• Using waves or ocean currents is being
researched as a source of hydropower
www.southeastasia.biz
Three Gorges Dam in China
www.livescience.com
Three Gorges Dam
• 1.5 miles long
• 574 feet deep
• $23 billion
• 13 cities and 1,300 villages were flooded
www.howstuffworks.com
• Benefits of Hydropower
• Readily available
• No pollution produced
• Constant source of power
• Drawbacks of Hydropower
• Damming rivers disrupts ecosystems, causes
sediment to build up and disrupts the natural
flow of a river
Geothermal
• Geothermal energy uses natural underground
heat sources
• When heat escapes the earth in the form of
steam, the steam is used to turn a steam turbine
which converts the heat energy into electrical
energy
• Benefits of Geothermal:
• When drilled correctly, little pollution is
produced
• Takes up a relatively small area, does not
disrupt the landscape
• Drawbacks of Geothermal:
• Can only be used in a limited capacity
• Very location specific
• May run out of steam
• May release hazardous gasses or minerals if
drilled improperly
Biomass
• Biomass is burning biomass fuel in a specialized
burner. Steam generated turns a steam turbine
which turns mechanical energy into electrical
energy
Biomass at the Denver Zoo!
• Trash and animal
waste is converted into
pellets
• The pellets are put into
a gassifier and heated
to 400 degrees!
• When hot enough, a
gas is emitted that is
converted by micro gas
turbines into electrical
energy
• Denver Zoo
• Benefits of Biomass
• Less waste in landfills
Readily available
• Drawbacks of Geothermal
• Not currently available on a large scale basis
USING RENEWABLE SOLAR
ENERGY TO PROVIDE HEAT AND
ELECTRICITY
• The European Union aims to get 22% of its electricity from
renewable energy by 2010.
• Costa Rica gets 92% of its energy from renewable resources.
• China aims to get 10% of its total energy from renewable
resources by 2020.
• In 2004, California got about 12% of its electricity from wind
and plans to increase this to 50% by 2030.
Energy Efficiency – renewable
energy sources
• Solar
• Wind
• Hydro
• Biomass
• Geothermal
USING RENEWABLE SOLAR
ENERGY TO PROVIDE HEAT AND
ELECTRICITY
• Denmark now gets 20% of its electricity from
wind and plans to increase this to 50% by
2030.
• Brazil gets 20% of its gasoline from sugarcane
residue.
• In 2004, the world’s renewable-energy
industries provided 1.7 million jobs.