Earth’s Resources
Earth’s Resources
• Most Energy Sources are nonrenewable
• Nonrenewable Resources
– Used up faster than the Earth can replace them
– Fossil Fuels
• Oil, Natural Gas, and Coal
• Formed from the remains of swamp plants and other
organisms that were buried and altered over millions
of years
Coal
Coal
• Most abundant fossil fuel
• Contains 50% plant remains
• Hydrocarbons can be extracted from coal
to form liquid and gaseous synthetic fuels
• As decaying plant material loses gas and
moisture, carbon concentration increases
Coal Formation
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•
•
•
Peat
Lignite Coal
Bituminous Coal
Anthracite Coal
(Cleanest Burning)
Oil and Natural Gas
Oil and Natural Gas
• Oil is thick black liquid hydrocarbon
• Natural Gas is a gaseous hydrocarbon that often
forms with oil, but above it, since it is less dense
• Americans obtain most of their energy from oil and
natural gas
• Natural Gas is used mostly for heating and cooking
• Oil is used in many ways included
– Heating oil
– Gasoline
– Manufacturing
Fossil Fuel Removal
Fossil fuels are removed from the ground
through mining or pumping
• Strip Mining (Open Pit)
– Upper layers of rock and soil are removed to
expose coal
– Used when coal deposits are near the surface
• Underground Mining
– Tunneling, drift mines, slope mines
Strip Mining
Fossil Fuel Removal
• Oil and Natural Gas are under pressure,
therefore they can be pump from the
ground
Fossil Fuel Reserve
Reserves
• Amount of fossil fuel that can be extracted at a
profit using current technology
• Current Reserves of Coal
– 250 Years
• US reserves of Natural Gas
– 60 Years
• Methane Hydrates (Located in ocean floor
sediments)
– Yield high amounts of carbon
– May be a source of methane in the future
Conservation
• Conserving fossil fuels will help slow down
the current consumption rate
Nuclear Energy
Nuclear Energy
• Produces Energy by
splitting an atom in a
process called fission
• Nonrenewable
• Produces Highly
Radioactive Waste
• Must be stored in a
Container for 10,000
years
Nuclear Energy
• Fusion
– Fusing of low-mass materials to form higher
mass substances
– Potential Clean Energy Source
– Current technologies do not exist to allow
fusion in a controlled manner
Renewable Energy Resources
Inexhaustible energy resources include:
• Sun
• Wind
• Water
• Geothermal
Solar Energy
Solar Energy
• Energy from the sun
• South facing windows can act as passive
solar collectors, warming exposed rooms
• Solar cells actively collect Sun energy and
convert it to electricity
• Solar energy is not readily useable on
cloudy days or at night
Wind Energy
Wind energy uses windmills to generate
wind
• Wind farm uses large number of windmills
to generate electricity
• Few regions of the world have strong
enough wind to generate electricity
• Wind does not always blow steadily, so it
is unreliable energy source
Hydroelectric Energy
• Electricity is generated from running water
flowing over dams
• Dams can create environmental problems
Geothermal Energy
• Energy obtained from hot magma or dry,
hot rocks inside Earth
Biomass
Biomass Energy
• Energy from burning organic material
• Can be replaced in a short period of time
• Examples
– Wood
• Causes pollution and disrupts natural habitats
– Corn
• Distilled into alcohol (Ethanol) added to Gasoline
• Ethanol production uses more energy than it produces
– Trash
• Air pollution and toxic ash residue