Perspectives on Alternative Energy

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Perspectives on Alternative Energy
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What we wish to learn

• What are the pros and cons of both renewable and
  nonrenewable energy?
• Is the implementation of renewable energy in
  modern society realistic?
• We will use coal as an example of renewable
  energy solar and wind power for nonrenewable
  energy

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World Energy Use

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Coal Pollutes

• Coals combustion adds more carbon dioxide
  emissions to the atmosphere than any other
  resource (38.2 of ALL CO2 IN THE WORLD from coal
  plants in 1999)
• Coal plants also emit toxins such as sulfur
  dioxide, nitrogen oxide, carbon monoxide,
  hydrocarbons, etc

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Coal Health Effects
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Coal Health Effects

• Coal mining deaths are relatively common
• In 2004, 6,434 Chinese miners died on the job
• The pollution from factories often enters houses

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Coal Pros

• The only thing that keeps some countries (i.e.
  China) using coal is because its -
• A) Cheap about 4 cents for every kilowatt-hour
  of energy produced, or 3,600,000 J
• B) Efficient when coal is burned, about 40 of
  its energy is converted into electricity

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Is coal worth it?

• Pros
• Its cheap
• Its efficient

• Cons
• It pollutes
• It releases lots of CO2 lots of global warming
  (?)
• Mining is dangerous
• Strip mining destroys the environment
• Its non-renewable

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Clearly,

• alternative forms of energy are necessary!

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Wind Power?

• While coal is terrible for the environment, wind
  power is not only a renewable resource, but it
  also doesnt pollute!

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Wind Power?

• In fact, wind is also pretty cheap its only
  3-4.5 cents/kilowatt-hour (kWh)
• BUT, thats because its making its money back
  over timethats the bonus of renewable energy
• Of course, it is expensive to install in the
  first place, around 800,000 for a big 750 kW
  turbine
• But over time, itll get even more back

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Wind Power?

• Wind power has about 20 conversion
  efficiencyonly about half as much as coal power
• There are two
• factors in determining how
• much power you will generate
• wind speed,and wind consistency

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Wind Power?

• Of course, wind power does have its drawbacks
• A) Wind farms take up a lot of space
• B) They can dominate a landscape that might
  otherwise have aesthetic value
• C) They can kill birds or interfere with
  television reception

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So what?

• Overall, wind power looks good!
• Implementation difficult in a rapidly developing
  country without (like China or India)
• Wind power- difficulty meeting such huge power
  demands
• Maybe slow implementationis the way to go

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How aboutSolar Power?

• Solar power is also a renewable form of energy

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Solar Energy?

• It is more expensive - at 30 cents/kWh
• Coal and wind power could operate in a 24 hr
  cycle, solar energy is only effective during a
  portion of the day.

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Solar Energy?

• The suns energy is typically harnessed through
  photovoltaic cells to convert the suns power
  into usable energy
• These cells convert the suns energy into
  electricity at 10-15 efficiency
• Large flat expanses of land are usually needed,
  BUT they can also be placed
• on rooftops

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Solar Energy?
There great payback over time!
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Solar Energy?

• A common use of solar energy is to heat homes

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So, which is the best?For price, its two
against one.
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So, which is the best?When the data is
extrapolated out - costs even out
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Conclusion

• Its not easy to quantify exactly which renewable
  resource is bettereach has its pros and its cons
• Renewable energy may not replace fossil fuels
  overnight, but logical implementation would be
  wise.