Download Lesson 6 Energy sources summary

Electricity production
Generally (except for solar cells) a turbine
is turned, which turns a generator, which
makes electricity.
Fossil fuels
Fossil fuels
In electricity production they are burned,
the heat is used to heat water to make
steam, the moving steam turns a turbine etc.
Fossil fuels - Advantages
• Relatively cheap
• Can produce a lot of energy
• Variety of engines and devices use them
directly and easily
• Easy to transport
Fossil fuels - Disadvantages
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Will run out (Non-renewable)
Coal in particular produces acid rain
Oil spillages etc.
Contribute to the greenhouse effect by
releasing greenhouse gases
Nuclear Fission
Heat
Heat from nuclear fission is used to heat
water, to make steam, which turns a turbine,
which turns a generator, which makes
electricity.
Nuclear power - Advantages
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High power output
Large reserves of nuclear fuels
No greenhouse gases
No acid rain
Nuclear power - disadvantages
• Waste products dangerous and difficult to
dispose of
• Major health hazard if there is an accident
• Produces material for Nuclear weapons
• Expensive to build and run
Solar power
Solar panels
• Simply heat water
Solar cells
• Produce electricity
Solar power - advantages
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“Free” energy (once installed)
Renewable
No grrenhouse gases
No acid rain
Solar power - disadvantages
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Only works during the day
Affected by cloudy weather
Low power output
Requires large areas
Initial costs are high
Hydroelectric power
Water storage in lakes
“High” water has GPE. AS it falls this urns
to KE, turns a turbine etc.
Tidal water storage
• Tide trapped behind a tidal barrage. Water
turns turbine etc.
Hydroelectric - Advantages
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“Free” once built
Renewable
No greenhouse gases
No acid rain
Hydroelectric - disadvantages
• Very dependent on location
• Drastic changes to environment (flooding)
• Initial costs very high
Wind power
Wind power - advantages
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“Free” once built
Renewable
No greenhouse gases
Ideal for remote locations
No acid rain
Wind power - disadvantages
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Works only if there is wind!
Low power output
Unsightly (?) and noisy
Best located far from cities
High maintainance costs
Wave power
OWC
Oscillating
water column
Wave power - Advantages
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“Free” once built
Reasonable power
Renewable
No greenhouse gases
No acid rain
Wave power - disadvantages
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Only in areas with large waves
Waves are irregular
Maintainance and installation costs high
Transporting power
Must withstand storms/hurricanes
Geothermal energy
Geothermal energy
• Wells are drilled into hot rocks beneath the
earth’s surface
• Cold water is pumped down to the hot rocks
• Hot water/steam used to drive turbines,
which turn generators, which produce
electricity.
Advantages
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Renewable
No greenhouse gases
No acid rain
“Free” energy once built
Disadvantages
• Expensive to build
• Not suitable in all places
Noooooooooo!
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“Eco-friendly”
“Green”
“Sustainable”
“Environmentally friendly”
“Clean”
Nuclear fusion
Nuclear fusion
• In the centre of the sun, hydrogen is fused
in helium. LARGE amounts of energy are
produced.