Turn It On!
How Do Power Plants Use Magnets
To Generate Electricity?
Nearly all the electricity you use is produced by large
generators that have coils of wire moving between
magnets. The magnets are very strong. There is a lot of wire
in the coils. The coils turn very fast. Where does the energy
to turn the coils come from? How is it used to turn the coils?
Most generators use turbines. Turbines look
a little like the sails of a windmill or the propeller
of a ship. As water or gas moves past a turbine,
the turbine turns. This motion is used to turn the
coils of wire in a generator.
Many power plants in Canada use water to
push turbines. Power plants that use water
power are called hydroelectric plants. The larger
hydro plants use dams to control the flow of
water past the turbines. With wind and water
energy, no fuels are used up, and there isn’t any
smoke or pollution from the power plant.
Steam is also used to push turbines. The
most common way to make the steam is by
burning a fuel such as coal, natural gas, or oil to
boil water. These fuels are called fossil fuels,
because they were formed over millions of years
from plant fossils. There isn’t enough fossil fuel
on Earth to last forever. That is why people have
looked for other ways to make steam.
Nuclear power plants use tiny amounts of a
metal called uranium to start a nuclear reaction.
The reaction releases heat, which is used to
make steam. Nuclear power plants don’t pollute
the air, but their waste is very dangerous. A
nuclear accident can be so dangerous that a
large area around the accident may be poisoned
for thousands of years.
Most fuels have to be mined and carried to a
power plant, but some energy sources deliver
themselves. Water and wind are two energy
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sources that do this. Windmills have been used
for over 1,400 years. Water power has been used
for even longer. One other source of energy that
delivers itself is solar energy. Huge mirrors can
be used to collect energy from the sun. This
energy boils water to make the steam to run a
generator.
• Which sources of electricity are renewable
and which are non-renewable?
• Which way of producing electricity is the most
efficient? least harmful to the environment?
most reliable? Make a chart to grade the
different sources of electricity.
TURBINE
▲ Hydro electric plant in James Bay, Quebec
Water
or gas in
Information Connection:
Sources of electricity
Water
or gas out
Which source of power do you think is used
the most in Canada? in your province? Check the
Internet or library to find out. Do you think this
source will be the one most used in the future?
Explain.
New ways of using the sun, the wind, water,
and other materials to make electricity are being
tried out all over the world. Many of these
sources of energy are free, and they are very
clean because there are no waste products. But
so far, these energy sources don’t produce very
much of the electricity that people use.
• Power plants don’t store electricity—they
produce it when it is needed. Most electricity is
produced at 6:00 pm. Why do you think most
people would need electricity at that time?
• What time of year do you think people use the
most electricity. Why?
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