Alternative Energies

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Alternative Energies
Before the bell rings…
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Turn in your graph and worksheet up front.
 Get out your book HW assignment from yesterday.
 Get out your notes and answer the following…
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What are the three fossil fuels, give an advantage and
disadvantage of each?
What are the different types of coal, and the characteristics
of each?
What is a major issue facing us using fossil fuels as a main
source of energy?
What are alternative energies?
Alternative Energies
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Energies that are not
fossil fuels. Most are
renewable.
The following are
renewable: hydropower,
solar, wind, geothermal,
biomass, hydrogen, tidal,
and wave.
Research toward
alternative energies
started in the 70’s due to
the oil embargo and are
continuing today due to
foreign oil dependency
and environmental
concerns.
About 8% of today’s
energy in the U.S. is
renewable.
Alternative Energy Overview
 Alternative
Energy Video
Hydropower
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This uses the mechanical
power of flowing water to
generate electricity. Power
depends on the amount of
water (flow) and the
distance it falls (head).
(diagram pg. 450)
 Accounts for 42 % of U.S.
renewable energies and is
the largest renewable
source for electricity –
10%.
 Will not increase in the
U.S. because most
suitable sites have been
used.
HydropowerImpacts
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Renewable, nonpolluting,
and reliable.
Costly to build and funds to
build new dams have not
been approved in more than
a decade.
Dams disrupt the
environment and create
different habitats.
Block fish migration (fish lifts)
Dams can fill with sediment
becoming useless if not
maintained.
Hydropower is on the decline
Fish
Ladder
Video
Wind
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Use of wind to spin turbine to
generate electricity.
 Researchers are looking for
ways to store energy and
reduce cost.
 Fastest growing energy
source in the world. (coastal
Europe)
 Electricity is almost as cheap
as fossil fuel in areas with
strong winds.
 Most effective on coasts,
mountains, and open plains
 Accounts for only 1% of our
alternative energy.
 (1% is enough to provide
energy to CO for one year)
Wind Impacts
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Few
environmental
impacts (noise,
space, damage
to bats and
birds)
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No air pollution
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Limited
globally due to
varying winds
Poor Bird
Messed Up
Biomass
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The burning of wood,
agricultural wastes,
sewage, algae, and
processed trash. Also
includes fuels made from
organic matter.
Various methods are
used to create fuels that
can be used for heating
or transportation. (could
possibly replace
petroleum)
Sugar crops and grains
can be converted through
fermentation by yeast to
produce ethanol. (can be
blended with gasoline)
 The
average American produces more
than 1,600 pounds of waste a year. If all
this waste were landfilled, it would take
more than two cubic yards of landfill
space. That's the volume of a box 3 feet
long, 3 feet wide, and 6 feet high. If that
waste were burned, the ash residue would
fit into a box 3 feet long, 3 feet wide, but
only 9 inches high.
Ethanol
 Usually
put
more energy
into making it
then you get
out of the
product itself!!!!
 Why do you
think people
still produce it?
Biomass
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Biodiesel is a substitute for
diesel engines and is made
from animal fat or vegetable
oils.
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Use is increasing with new
technologies.
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Accounts for close to 50% of
alternative energy (4% of the
total energy used) in this
country. Major source for
Hawaii.
Biodiesel
Bagasse-Hawaii
Biomass-Impacts
 Some
air
pollution.
 Processing of
some organic
wastes release
hazardous
chemicals.
 Responsible for
forest destruction
and soil erosion in
rainforests.
(burning of wood)
Geothermal
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Uses the natural heat
(dry heat, steam, or hot
rock) trapped in the
earth to heat homes or
produce electricity.
(diagram pg. 476)
Power plants must be
near the source
because too much
energy is lost during
transportation.
Accounts for 6% of our
renewable energy (.4%
of total US electric
generation).
California has 34 geothermal power plants,
which produce almost 90% of U.S. geothermal
electricity.
Nevada has 16 geothermal power plants.
Hawaii, Idaho, Montana, and Utah each have
one geothermal plant.
Impacts
 It
is limited to certain areas.
 Nothing is burned so there is limited
air pollution.
 Harmful gases can sometime be
vented with heat and land surfaces
may collapse.
Tidal
 Converts
the
mechanical energy
from ocean tides to
electricity.
 Limited to coastal
regions and
therefore will never
be a major energy
source in this
country. (Canada,
China, and France)
 Cool
Tidal Video
Wave
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Waves force water up a large tower pushing the
air up over a turbine to generate electricity.
(Norway)
Hydrogen Fuel
 The
changing of hydrogen gas into a
fuel source (gas or liquid)
 Makes up ¾ the mass of the universe
and is the lightest element.
 Requires natural gas (methane) and
water vapor is the only product given
off when burned
 The Department of Energy is looking
into expanding its use (fuel cell
technology)
HFuel
 It
would require new equipment and
engines to burn it (fuel cells)
 Hydrogen fueled cars have been made.
 * Check out this web site:
www.eere.energy.gov/hydrogenandfuelcell
s/
Impacts
 Pollution
free.
 It is too expensive and difficult to
store.
 It could one day replace gasoline
engines and our dependency on
foreign oil.
 A transition from fossil fuels to
hydrogen fuel will take a lot of time
and money.
is the so-called “chicken and egg”
problem that hydrogen developers are
working hard to solve. Namely: who will
buy hydrogen cars if there are no refueling
stations? And who will pay to build a
refueling station if there are no cars and
customers?
 This
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