Electricity Fact Sheet
What is Electricity?
It is a form of energy. It is difficult to explain what electricity
really is because:
- Electricity has no weight - we cannot weigh it. And yet
electricity can be used to lift or haul thousands of tonnes
of material.
- Electricity has no shape - we cannot see electricity.
And yet it produces light at the flick of a switch.
How is Electricity Made?
The majority of our electricity is made in coal-fired power
stations.
- Heat from burning the coal changes water to steam.
- The steam is forced into a turbine, which is made up of
a shaft with a row of blades.
- The shaft is connected to a generator rotor.
- When steam is forced through the turbine it rotates very
fast making the generator rotor spin.
- As the rotor spins, electrons in the wire of the stator
move backwards and fowards.
- The moving electrons are called the electric current.
Coal is a non-renewable resource.
What other sources of energy can be used to generate electricity?
Water, wind, sun, gas diesel fuel, tidal energy, waves and
geothermal energy. Nuclear power also uses steam to operate
a turbo-generator. New research is going on all the time in
an effort to reduced global warming attempt
to use renewable sources of energy.
Do you know what BAGASSE is? It is the waste
produced from milling sugar cane. The bagasse is plant fibre.
It is burnt to produce steam and electricity for the operation
of the mill. Some of the electricity is also made available
for sale into the State electricity grid.
Water A hydroelectric power station uses
the force of water to turn turbines, which drive generators
to produce electricity. Water can be stored in a dam and released
at intervals when required. The greater the height the water
has to fall, the greater the volume of water forced through
the turbines and the greater the amount of electricity produced.
You can see an early hydroelectric power station on the Electric
Memories panels. What is the name of it?
Wind The latest wind turbines were based
on the design of the old windmills. The force of the wind
in very windy places, such as Thursday Island, works in a
similar way to the force of water. A wind farm is the term
for a group of wind turbines. Do you know where the wind farms
are in Queensland? Can you find out how many wind farms there
are in Australia? Can you think of any advantages or disadvantages?
Sunlight is also used to produce electricity.
Solar (photovoltaic) cells convert light from the sun into
electricity. Geo-thermal energy is stored deep down below
the Earth’s surface. Some work is being done in Birdsville
to tap the geo-thermal energy there. Birdsville is too far
to receive a supply of electricity from its nearest large
power station.
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