10. Fossil fuels are used to produce two
kinds of energy that are very
important to us.
Let’s first look at mechanical
energy—the energy of moving
things. You and others depend on
many things that move.
What are some of these things?
12. But in order to move, all
these vehicles must have a
fuel.
What fuels do these vehicles
burn?
13. The fuel for
each of these
vehicles usually
comes from
crude oil, a
fossil fuel.
14. Remember
all the fuels
that come
from crude
oil?
Gasoline, diesel
fuel and jet fuel
are the fuels for
transporation.
15. Another form of energy we
depend upon is electricity.
But electricity has to be generated.
Just how is electricity generated?
16. To generate electricity you
have to turn a magnet
inside a coil of wire or turn
a coil of wire inside a
magnetic field.
17. Open this website to see
how this is done.
http://new.wvic.com/index.php?option=com_content&task=view&id=9&Itemid=46
18. And what force is used to
turn the wire or magnet?
Often it is steam.
Coal and natural gas
(two more fossil
fuels) are burned
heating water to
make steam.
19. The burning coal The water
Coal is changes into
burned. heats the water.
steam.
The steam turns The turbine turns Electricity is
the turbine. the coil of wire generated.
inside the magnet.
21. But there are many problems with
burning the three fossil fuels.
1. coal
2. natural gas
3. crude oil --gasoline and
diesel fuel
What are some of these problems?
22. • They are limited and very expensive.
-Crude oil is becoming hard to find
and even more expensive to obtain.
• Burning these fuels puts:
-pollutants into the air which are
harmful to our health and
-carbon dioxide into the air which
leads to global warming.
• Accidental spills, as in the recent
Gulf Oil spill, pollute our water.
23. So what are we to do?
Man can use other (alternative)
forms of energy to move our
vehicles and generate electricity
.
What are some of these
alternative forms of energy?
25. Biomass is organic material made
from plants. Biomass contains
stored energy from the sun.
Some examples of biomass fuels
are wood, corn, sugar cane and
some types of garbage.
But where do these plant materials
get their energy?
26. During
photosynthesis, pl
ants change the
sun’s radiant
energy into
chemical energy
in the form of a
sugar called
glucose.
So the energy from the sun is actually stored in
the structure of the plant.
27. When plant material is burned, the
stored chemical energy is released as
heat. If you have a fireplace, the wood
you burn in it is a biomass fuel.
Wood waste and certain garbage
(forms of biomass) can be burned to
produce steam for making electricity
and also to provide heat for homes
and industries.
28. Sugar cane and corn can be used to
produce ethanol, a liquid fuel, that can be
added to gasoline for vehicles.
Biodiesel, another transportation fuel, can
be produced from left-over food products
like vegetable oils and animal fats.
40. First, solar cells change the energy
from the Sun (solar energy) directly
into electrical energy.
41. It would take many many solar cells to
provide for all of a city’s electrical needs.
42. The second way the Sun can be used to fluid
produce electricity is by using: mirrors
Concentrating Solar Power Plants togenerate
electricity. Mirrors reflect and focus the sun’s
light on a
container
of fluid. The
hot fluid changes
water into
steam which is
used to power
a generator.
43. Can you think of
In summary
some
advantages of
These
these
alternative
are some
forms of
of the
energy?
alternative
Do they have
any
forms of
disadvantages?
energy
44. Below is a website that has good reading
material that you can print (in black and
white) alternative energy sources such as
wind, solar, biomass and geothermal.
Under the tab student choose Energy
Infobooks. Both the Complete Primary and
Elementary Energy Infobooks are excellent.
So are the individual printouts on each
energy source such as
coal, petroleum, natural
gas, wind, solar, etc.
(http://www.need.org/)