energy for the future

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Electricity Generation

Generators Use energy to generate electric currents. A moving magnet pushes the electrons along a

wire. The energy used to move the magnet is carried by

the electric current.

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magnet

Coil of wire

torch bulb

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The inventor of the generator

Michael Faraday 1791-1867invented the generator in 1831.

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What do we need to make a generator for a power station?

• Strong magnets• Lots of wire

then lots of energy

to turn the generator.

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• Generators in power stations supply electricity to factories,

homes and schools.

• These generators are in power stations

• and are huge!

Factories, homes and schools need huge amounts of energy

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Generators in power stations are very, very big

Huge generators need huge amounts of energy.

The energy turns the generators.

The electric current carries the energy to where it is needed.

Size of a person

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How can a generator be turned?

Source of steam

Turbine

Steam can be used to turn a turbine to turn the generator.

A power station

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electric current

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How can water be heated to make steam?

Old way:Burn coal

The smoke is dirty and pollutes the atmosphere. Also produces lots of carbon dioxide which is a green house gas – heats up the Earth.

Newer way:Burn gas

Gas is cleaner than coal but still makes lots of carbon dioxide

Eventually the world will run out of coal and gas.

Steam from nuclear energy

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+

splits to give

Steam from the Earth

70000 C

5000 C

Energy from the Earth

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NREL geo pacific gas and electric

Electricity from waste

waste can be burned - to boil water - to make steam- to turn generators.

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How else can we turn a generator without polluting the Earth?

Use flowing water.

Hoover Dam in USA – 220m high

top of dam

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HydroelectricityRunning water turns the generator

(Tennessee Valley Authority)

Water from a mountain lake

Does not pollute the atmosphere.

The dam must be high in mountains.

Waves

Energy from waves can be used to turn generators.

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We can make a windmill When you blow

the windmill it turns.

The moving air pushes the blades round.

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What happens if you blow harder?

Wind can turn generators

Now modern wind turbines are used to turn generators.

Do not pollute the air. Wind is not used up. But sometimes the wind

does not blow.16

Many years ago windmills were used to turn mill stones to grind grain.

Then we place the winds in these types of areas.

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Solar cellsUse solar cells to change the energy in sunlight into electricity

parking meter

Solar cells

traffic sign

– no generator needed - needs lots of sunlight.

The space station has huge solar panels

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The framework is 109 metres long.NASA

The International Space Station uses solar panels to collect energy, making it possible for scientists to live on board and do experiments.

Fusion Makes the Sun shine.

Scientists are finding ways to get huge amounts of energy. when small atoms join together,

energy is given out– like in the Sun.

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+gives

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Fossil fuelsCoal - pollutionGas - pollutionOil - pollution

Renewable sources – do not run outHydroelectricity – needs mountainsWind - only works when wind blowingWaste & rotting vegetation – greenhouse gasesSunlight – best in sunny countriesGeothermal – only in countries with hot springsWaves – small scale only – so far

Energy from nuclear reactionsFission – waste needs very careful handlingFusion – waste less dangerous

will not run out - but very difficult !

Energy Sources:

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Saving electricity is important to our future.

TO ONE & ALL… TO ONE & ALL…

Any QUERIES…….?Any QUERIES…….?