2. On July 4, 1997, the Pathfinder spacecraft bounced
to a stop on Mars. The next day, the rover
Sojourner rolled out of one of the lander petals
onto the surface of the planet to begin its mission
of exploration.
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3. Sojourner was able to move around the planet and
examine rocks like this one named “Yogi” – located
20 feet from the Pathfinder lander – thanks to
the power generated by the solar panel on its
back.
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4. Dramatic as this was, it was just one use
of solar energy.
To many students, exciting projects like
this are what solar energy is all about.
But there really is much more to solar
energy technologies, how they are being
used, and how they impact our lives today.
This presentation will introduce you to the
entire field of solar energy.
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5. Let’s begin our overview of
solar energy by asking:
What do you see here?
Take a close look –
is this the profile of a
beautiful young lady,
or the face of an ugly,
old woman?
They’re both here, but for
a variety of reasons that
make up your own
individual psychological
make-up, some of you see
one woman, some the
other.
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6. When people think of solar
energy, the same thing often
happens. Some see it as
something for the future,
others see it as something
that is here today.
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7. If you think solar energy is something
to be used in the future . . .
you may be picturing
something like this
solar array used by
the space shuttle to
provide for power
needs in outer space.
There are people who
think that solar
energy is something
not quite down-toearth and not ready
to use today.
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8. However, there are other people who think of
solar energy as something that’s been around for a
long time.
Solar collector for
heating water
A home in California in 1906
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9. For hundreds of years, people have wanted to harness
the sun’s power for weapons, heating, and many other
uses to make their lives more comfortable.
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10. Actually, the first solar water heating
collector appears to have been built
in the 18th Century by a Swiss
scientist who constructed a simple
wooden box with a glass top and a
black base. It trapped solar energy,
and the collector reached a
temperature of 190 degrees
Fahrenheit.
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11. So which view of solar energy
-- for the future or for today –
is correct?
Probably a little of both.
Solar energy will certainly play an important
role in the future energy needs of our
planet, but it’s also here today and ready
for hundreds of uses in homes, businesses,
and industry.
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12. The sun is an inexhaustible power
supply. It brings enough energy to our
planet every single day to meet a full
year’s worth of energy for everyone on
Earth.
And during the past century – back to 1891,
in fact, when the first solar collector was
manufactured in the United States, U.S.
industry has developed a variety of
products that have proven both reliable
and cost-effective in meeting all kinds of
energy needs.
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13. The batteries in this solar-powered light in a
remote part of Key West, Florida, are charged by
the sun during the day to provide power for street
lighting at night.
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14. But to many people,
solar power today
means just reliable
calculators,
watches and other
simple home
products like this
lantern that use
solar power
instead of
electricity to
charge the
batteries.
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15. They don’t realize that millions of
people around the world use
solar energy because it is the
only available, reliable power
source for many of their basic
needs such as lighting and water
pumping.
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17. The owner of a small laundry in northern Florida
tried to build his own concentrating system for
water heating. (We don’t know if the sign in the
background was put up before or after this
homemade system was built.)
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18. But we do know that growing public concern
about environmental problems . . .
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19. including global warming, acid rain and toxic air
emissions, has in recent years turned a great deal
of attention to environmentally friendly solar
energy systems.
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