Renewable and Alternative Energy

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Renewable and Alternative Energy

• Leon County Schools
• 8th Grade Comprehensive Science

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What is Renewable Energy?

• An energy source that
• is replaced quickly by natural processes
• is environmentally friendly and does not cause
  pollution
• does not contribute to global warming
• does not come from fossil or nuclear fuel
• can not be depleted

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Examples of Renewable Energy

• Solar
• Wind
• Tidal
• Hydropower
• Geothermal power
• Biomass

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Solar PowerHarnessing solar energy to produce
electricity

• Positive
• The most abundant source of energy on Earth
• Does not pollute the planet
• With the right technology, could easily supply
  our current and future energy needs.
• Negative
• Some hazardous materials are used in the
  production of solar panels
• Solar panels take up a lot of space.
• Solar panels are expensive and are not very
  efficient yet

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Wind PowerUses the power of the wind to turn
turbines which produces electricity

• Positive
• Environmentally friendly
• Low cost
• Wind farms can be established on land or in the
  ocean
• Negative
• Only produces energy when the wind is blowing
• Large turbines can injure birds and disrupt
  ecosystems due to noise

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Tidal PowerTides are used to turn turbines to
produce electricity

• Positive
• Non-polluting
• Reliable and predictable
• Negative
• low capacity for producing electricity
• misses peak demand times
• could disrupt or damage aquatic ecosystems

http//www.youtube.com/watch?vqRUl1mJQHmcfeature
player_embeddedlistPL7AC997353CC33B26
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HydropowerDams use the flow of water to turn
turbines to produce electricity

• Positive
• Currently supplies 20 of the worlds electricity
• Non-polluting
• Low maintenance, low cost once built
• Negative
• Can cause a lot of damage to ecosystems around
  them
• Takes years and a lot of money to build

Image take from www.clipartof.com
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GeothermalUses heat found within earth to
produce steam to turn turbines

• Positive
• Clean energy stored within earth
• Cannot be depleted and is not harmful
• Negative
• High installation costs
• Not available everywhere

Image take from abcteach.com
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What is an Alternative Energy source?

• An energy source that
• may or may not come from natural processes.
• can be depleted in some cases
• may not have the undesirable effects of fossil
  fuels (pollution, etc)
• May be more efficient than the current fuel used

Image taken from http//www.google.com/images
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Examples of other Alternative Energy Sources

• Alcohols such as methanol and denatured ethanol
• Biodiesel
• Natural gas (compressed or liquefied)
• Propane
• Hydrogen
• Coal-derived liquid fluids

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Biomasswood, waste, garbage, landfill gases and
alcohol fuels are burned to produce heat and
electricity

• Positive
• Abundant, found everywhere
• Less CO2 emissions than fossil fuels
• Negative
• Produces some air pollution (CO2)
• More expensive than coal

Image taken from http//cr.middlebury.edu/es/alte
nergylife/sbiomass.htm