Solar Energy

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Solar Energy
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What is Solar Energy Used For?

• Solar cookers
• Solar towers
• Electricity

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Solar Cookers

• Use sun to obtain energy/heat and channel it to
  your objective (greenhouse effect)
• Invented by Horace de Saussure (1767)
• reported cooking fruits at temp. 87.5
• THREE BASIC KINDS
• (1) Box Cookers
• (2) Panel Cookers
• (3) Parabolic Cookers

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THREE BASIC KINDS

• Box Cookers
• slow, even cooking
• large quantities of food
• vary this kind of cooker by (1) changing the
  number of reflectors or (2) slanting the face
  towards/away from sun
• can be made at home out of a cardboard box

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THREE BASIC KINDS

• Panel Cookers
• recent
• Roger Bernard in France
• design many flat panels direct suns rays onto
  a pot inside a plastic bag or under a glass bowl
• advantage quickly and cheaply made

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THREE BASIC KINDS

• Parabolic Cookers
• concave disks
• focus light onto bottom of a pot
• advantage cooks food as fast as regular stove
• disadvantage complicated to make, must be
  monitored to follow sun, can cause eye injury and
  burns

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Solar Towers

• Built to observe the sun (solar rotation,
  splitting of sunspots, etc.)
• like a telescope
• consists of metal framework, complicated lens
• longest focal length of any solar tower telescope
  in the world 150 ft tower in Arizona

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Electricity

• Solar power photovoltaics
• use suns energy directly to produce electricity
• complicated silicon cells used in the process
• advantage no moving parts, heat, noise,
  pollution
• disadvantage very expensive
• examples solar powered lights in the yard, solar
  powered traffic lights, calculators
• future as utility costs increase on other types
  of power, solar power will be more common and
  competitive with other types of power, more

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Efficiency of Solar Energy

• Photovoltaics not very efficient application of
  solar energy (expensive, complicated)
• on a large scale good outlook for future and
  efficiency (Solar Space Power Satellites beam
  collected energy by microwaves)

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Efficiency of Solar Energy contd

• Solar cookers efficient on small scale
• good for home use and cooking food but thats it

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Benefits Costs

• No pollution
• cheap (solar cookers)
• does not destroy environment
• uses a renewable resource
• provides alternative to using natural gas stoves,
  etc. and other nonrenewable resources

• Not very efficient on a large scale (solar
  cookers)
• expensive (photovoltaics)

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How can we conserve our energy and
resources? THE ANSWER COMES UP EVERY
MORNING (El Paseo Solar Energy Association)