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Why are we studying this?
What are our main energy sources?Do we have enough energy sources?
Glossary words from last lesson
• Earth’s crust• Mineral ore• Open-cut mining• Underground mining
Fossil fuelsEnergy is stored in the form of fossil fuels below the Earth’s surface: coal, oil & natural gas– Fossil fuels were once the remains of ancient
plants and animals– Formed before the dinosaurs roamed the earth
(300 million years ago)
Burning fossil fuels converts the stored energy into usable forms E.g. Heat, movement, light
Non-renewable resource!
Fossil fuels• Coal formed from the remains of dead trees and
plants which had fallen into swamps and were unable to rot fully under water
• Layer of partially rotted plant material: peat• Over time the layers of peat built up and then
rocks formed on top of them (sedimentary rocks)
Coal• The pressure from the rocks above compressed the peat• The heat from the Earth’s crust made the peat warmer
and drove out most of the remaining water, forming coal • Brown coal is young coal, Black coal is produced by
longer compression and the driving out of more water. It is harder and drier.
Brown coal (lignite)
Black coal(anthracite)
Coal formation
Brown coal Black coal
Coal mining• Major brown coal reserves in Victoria are found in
Latrobe Valley• More than 80% of Victoria’s electricity is generated
here -> what problems are associated with using coal?• The coal is close to the surface so open mining is used• If it is deeper in the ground underground mining must
be used- more expensive & more dangerous
Oil and gas• Dead plants and sea animals buried at the bottom of the sea
decomposed and were compressed over millions of years• Chemical reactions gradually produced oil and natural gas• Oil is taken from the Earth’s surface and converted to usable fuels in
oil refineries, E.g. Diesel and petrol for cars, kerosene for lamps and camping stoves
• Gas is also collected and mostly used for heating and to power stoves for cooking
Fossil fuels
Question 13 on page 243 Think, pair, share
• Answer this question by yourself: • Turn to your friend and discuss your choices
and your reasoning– Did you have different reasons for picking the
same items?• Share with the class
Glossary words covered so far
OilNatural gas
Earth’s crustMineral oreOpen-cut miningUnderground miningPeatFossil fuelsBrown coalBlack coal
Homework:• 1. Use your textbook to produce a Glossary
containing definitions to all the terms I have given you today. I will be testing your knowledge of these terms next lesson!
Plant projects: water your plants, those who are treating plants with something dissolved in water make sure you do this.
Nuclear energy• Nuclear energy is produced from metals called
uranium or plutonium. • renewable or non-renewable??• Energy is produced by a splitting a molecule in two
(‘splitting the atom’). This energy is used to produce steam which drives turbines and produces electricity
• Uranium is radioactive and gives off energy called radiation, radiation sickness in humans can be fatal
Solar energy• Solar energy is produced when
solar (photovoltaic) cells transform light energy from the sun into electrical energy
• can be used immediately or stored in a battery
• In the past solar power stations uses the suns rays to heat up oil, the oil then heats up the water and the steam drives turbines
• Modern power stations use huge arrays of solar panels to produce energy
Wind power• Wind is caused by the sun unevenly heating the Earth and its
oceans• A single wind turbine can produce enough energy to supply
700 homes, but some people think they are noisy and unsightly
• Wind can turn a turbine without the need to produce steam or emit carbon dioxide like the fossil fuels
• Wind energy is renewable
Biomass• Dead and rotting plant and animal tissue produces
gases such as methane, methanol and oils that can be used as fuels to drive small turbine electricity generators, E.g. Rubbish tips
• Renewable resource• Worm farms process food waste• The nutrient-rich fluid produced can be used as
fertiliser for gardens
Ocean wave energy• The up and down movement of the waves can
be used to drive motors that generate electricity
• Waves are produced by the effect of the wind on the ocean
Renewable ornon-renewable??
Tidal energy
• Power stations harness the energy of the rising and falling of the tides
• Turbines are placed at the entrance of a bay and the water moving in and out of the bay drives the turbines as the tides change
Renewable ornon-renewable??
Geothermal energy• Energy transferred from rocks just below the
Earth’s surface is used to produce water from steam, this steam drives turbines in geothermal power stations.
• In New Zealand, but there has been research to use this technology in Australia.
Hydroelectric power
• Hydroelectric energy is produced by using falling water to turn turbines and produce electricity
• Requires a constant source of free flowing water so turbines are often built in high-altitude areas
• Water is held in Dams and then released to cause free-flowing water which turns turbines
Glossary words covered so far
OilNatural gasNuclear energyOcean wave energyTidal energyGeothermal energyHydroelectric power
Earth’s crustMineral oreOpen-cut miningUnderground miningPeatFossil fuelsBrown coalBlack coal
Science Quest 7 p.259 Table 1- make table and fill in the answers.