Transcript Alternative Resources Layered Curriculum Notes

Alternative Resources
Layered Curriculum Notes
Swainston MS
Science 8
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Alternative Resources
• Nonrenewable Resources
– Fossil Fuels
• Coal, crude oil (petroleum), natural
gas
– Biomass
• Renewable Resources
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Wind Energy
Solar Energy
Hydroelectric Energy
Tidal Energy
Geothermal energy
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Fossil Fuels
Fossil fuels are formed by the anaerobic decomposition of remains of
organisms including phytoplankton and zooplankton that settled to the
sea (or lake) bottom in large quantities under anoxic conditions,
millions of years ago.
Fossil fuels are oil, coal and natural gas. In 2006 primary sources of
energy consisted of petroleum 36.8%, coal 26.6%, and natural gas
22.9%, amounting to an 86% share for fossil fuels in primary energy
production in the world.
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Crude Oil
•Crude oil is a smelly, yellow-toblack liquid and is usually found
in underground areas called
reservoirs.
•Scientists and engineers explore
a chosen area by studying rock
samples from the earth.
•Measurements are taken, and, if
the site seems promising, drilling
begins.
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Natural Gas
•Natural gas is a gas
consisting primarily of
methane.
•It is found associated
with fossil fuels, in coal
beds.
•It is created in marshes,
bogs, and landfills.
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Coal
•Coal is a readily combustible black or brownish-black sedimentary
rock normally occurring in rock strata in layers or veins called coal
beds.
•At current usage, the coal supply will last 1500 years. However at
a 5% growth rate the coal supply will last only 86 years.
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Biomass
• Biomass is made up of
organic material of
animals & plants
• It is stored energy from
the sun.
• Biomass makes up 4%
of the US use in energy.
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Alternative Resources
• Nonrenewable Resources
– Fossil Fuels
• crude oil (petroleum), natural gas
– Biomass
• Renewable Resources
– Wind Energy
– Solar Energy
– Hydroelectric Energy
– Tidal Energy
– Geothermal energy
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Wind Energy
•Wind is simply air in motion. It is caused by the
uneven heating of the Earth's surface by the sun.
•Daily Wind Cycle
•During the day, the air above the land heats
up more quickly than the air over water.
•The warm air over the land expands and
rises, and the heavier, cooler air rushes in to
take its place, creating wind.
•At night, the winds are reversed because the
air cools more rapidly over land than over
water.
•Used to convert wind energy to electric power
using turbines.
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Solar Energy
• Solar Energy is better for the
environment than traditional
forms of energy.
• Solar energy has many uses such
as electricity production and
heating of water through
photovoltaic cells and directly for
drying clothes.
• Solar energy is responsible for
weather patterns and ocean
currents.
• Clouds, pollution and wind can
prevent the sun's rays from
reaching the earth.
Other Interesting Facts
about Solar Energy:
•Da Vinci predicted a solar industrialization
as far back as 1447.
•In one hour more sunlight falls on the
earth than what is used by the entire
population in one year.
•A world record was set in 1990 when a
solar powered aircraft flew 4060km across
the USA, using no fuel.
•Fierce weather cost the world a record
$130 Billion in the first eleven months of
1998- more money than was lost from
weather related disasters from 1980 to
1990 ($82 Billion).
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*Photovoltaic Cells*
We have a solar farm in our valley at Nellis AFB
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Photovoltaic Cells
• What are they?
– Thin wafers of silicon
• Similar to computer chips
• Much bigger
• Much cheaper
– Silicon is abundant (sand)
• Non-toxic, safe
– Light carries energy into cell
– Cells convert sunlight energy
into electric current-they do
not store
– Sunlight is the “fuel”
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Hydroelectric
• Hydropower is the renewable
energy source that produces
the most electricity in the
United States.
• It accounted for 6% of total
U.S. electricity generation and
67% of generation from
renewable resources in 2008.
• Relies on the water cycle
• Mechanical energy is
harnessed by hydropower
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Tidal Energy
• The power of the tides can be
harnessed to produce electricity.
• Similar to the more conventional
hydroelectric dams, the tidal process
utilizes the natural motion of the tides
to fill reservoirs, which are then
slowly discharged through electricityproducing turbines.
• Advantages
– Tides rise and fall every day in a constant
pattern
– No fuel to run the plant
– It produces clean energy
• Disadvantages
– Altering the ecosystems
– Only produces energy when there are tidal
serges
– Only available in small number of regions
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www.mywindpowersystem.com
Geothermal
Energy
• The energy stored in the mantle of the
earth is harnessed from the internal
heat of the planet and can be used to
generate steam to run a steam turbine.
This in turn generates electricity, which
is a very useful form of energy.
• Advantages
– Cost of land is usually less expensive
– Low running costs
– Clean energy with no pollution
• Disadvantages
– Must be harnessed from deep within the
earth
– Harmful gases come from the sites
– Suitable hotspots are located near fault
lines and volcanoes
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