Electricity is generated by using another form of energy, such as coal, natural gas, nuclear, or renewable resources, to produce steam that turns a turbine connected to a generator; the turbine spins a coil of wire inside a magnet, creating an electric current; other methods of generating electricity include using wind, water, or solar energy to directly turn the turbine or create electricity via photovoltaic cells.
3. Electricity
So useful
So scary
How is it generated?
4. Let’s look at how electricity, one form of
energy is generated.
But remember, energy cannot be created
or destroyed. It can only be transformed
from one type to another. This means that
to generate electricity, we have to use
another kind of energy to fuel the process-
in this world you just don't get something
for nothing!
5. An electrical generator is made up of the following
parts: a strong magnet and copper wire that turns
inside the poles of the magnet.
6. A simple electrical generator
A magnet with
north and south
poles
The wire turning
Electrons flowing
7. To cause electrons to flow through the wire, we
must have something to spin the loop of wire.
What kind of energy is motion?
So to get electrical energy from a generator we
must have ______________ energy.
8. With this generator
what provides the
mechanical energy?
How would you like to
turn the wire to generate
all the electricity you use?
What about here?
9. Yes, steam is often used to turn a blade shaft
called a turbine which then turns the wire
inside the magnet generating electricity.
turbine
10. steam turning turbine turning
the turbine the wire inside a transformer to
the magnet make the electricity
less strong
Wires to take the
electricity to our
homes
water being
heated to make
steam
11. Now we have to find something to heat the
water to make steam.
Most often either coal or natural gas is burned
to heat the water changing it to steam.
The steam turns the turbine which turns the
wires inside the generator producing electricity.
12. Here is a power station that burns coal to
generate a flow of electrons in a wire which
travels to a house through power lines.
13. When coal or natural gas is burned to generate
electricity____________ energy is changed to
____________ energy to electrical energy.
14. Sometimes nuclear energy is used to heat the
water to make steam that turns the turbine.
In this case, _________ energy is changed to
___________ energy to _________ energy.
15. Most power plants need steam to generate
electricity. The steam rotates a turbine that
activates a generator, which produces
electricity. Most power plants still use fossil
fuels to boil water for steam. Geothermal
power plants, on the other hand, use steam
produced from reservoirs of hot water found
a couple of miles or more below the Earth's
surface to drive the turbines.
16. If you drill deep down into the Earth's
crust, the temperature rises dramatically..
17. Deep underground in these hot rocks are
pools of hot water and steam. When
released this steam has tremendous
amounts of energy and can be used to
turn a steam turbine.
Steam rising in pipe
Pools of hot water
and steam
18. A few power plants do not use steam to turn
the turbines. Wind pushing
the blades of a windmill can
cause the turbine to rotate.
19. In other plants, flowing water in a river or
waves in the ocean can be used to turn a
turbine to generate electricity.
20. Here flowing water held back by a dam on the
river is powering the turbine.
21. In this instance, the motion of the waves forces
air in and out of a chamber which then turns
the turbine.
23. At this link you can find an animated slide show
illustrating examples of energy resources used to
generate electricity.
http://www.childrensuniversity.manchester.ac.uk/interactives/science/energy/electricity
/
24. On your paper, draw a picture of a simple
electrical generator. Label the parts and explain
how it works.
Steam is usually used to turn the turbine. List
the energy resources that can be used to heat
water making steam to turn the turbine inside
the generator.
What other energy resources that do not use
steam can be used to turn the turbine inside the
generator?
What energy resource does not need a
generator and can be directly converted into
electricity?