Presentation on theme: "Energy for the future Electricity Generation - Part 2."— Presentation transcript:
1Energy for the futureElectricity Generation - Part 2
2Generators 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.magnetCoil of wiretorch bulb
3The inventor of the generator Michael Faradayinvented the generator in 1831.
4energy What do we need to make a generator for a power station? Strong magnetsLots of wirethen lots ofenergyto turn the generator.
5Factories, homes and schools need huge amounts of energy Generators inpower stations supplyelectricity to factories,homes and schools.These generators arein power stationsand are huge!
6Generators 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
7How can a generator be turned? Steam can be used to turn a turbine to turn the generator.TurbineSource of steam
9How can water be heated to make steam? The smoke is dirty and pollutes the atmosphere.Also produces lots of carbondioxide which is a green house gas –heats up the Earth.Old way:Burn coalNewer way:Burn gasGas is cleaner than coal but still makes lots of carbon dioxideEventually the world will run out of coal and gas.
10Steam from nuclear energy Nuclear reactors can be used- to split atoms- to release energy- to boil water– to make steam- to turn the generators.+splits to giveThis does not cause pollutionbut some waste is very dangerous and has to be handled very carefully.
11Steam from the Earth It is hot inside the Earth 70000 C5000 C- giving energy to generate electricity.In some countries there are hot rocks close to the surface of the Earth.
12Energy from the EarthIn some countries energy from the Earth can be usedto boil waterto turn generators.This does not cause pollutionand will not run out.NREL geo pacific gas and electricBut is not an option in the UK !It would need very very deep holes!
13Electricity from waste Vegetation and animal dung give off energy as they rot. This can be used to heat homes and greenhouses directly.Also waste can be burned- to boil water- to make steam- to turn generators.The process uses up waste.But produces carbon dioxide.
14How else can we turn a generator without polluting the Earth? Use flowing water.top of damHoover Dam in USA – 220m high
15Hydroelectricity Running water turns the generator Water from a mountain lake(Tennessee Valley Authority)Does not pollute the atmosphere.The dam must be high in mountains.
16Waves Energy from waves can be used to turn generators. We have lots of waves in the seas around the UK.Does not cause pollution.There are more problems to solve.
17We can make a windmill When you blow the windmill it turns. The moving air pushes the blades round.What happens if you blow harder?
18Wind can turn generators Many years agowindmills were used to turnmill stones to grind grain.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.
20Solar cellsUse solar cells to change the energy in sunlight into electricity– no generator needed- needs lots of sunlight.Solar cellstraffic signparking meter
21The space station has huge solar panels The International Space Station uses solar panels to collect energy, making it possible for scientists to live on board and do experiments.NASAThe framework is 109 metres long.
22+ 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.Will not run out.Does not pollute the air.The future? Not possible for another 20 years!+gives
23Energy Sources: Fossil fuels Renewable sources – do not run out Coal - pollutionGas - pollutionOil pollutionRenewable 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 farEnergy from nuclear reactionsFission – waste needs very careful handlingFusion – waste less dangerouswill not run out - but very difficult !
24You will have to choose ! Re-cap A generator generates an electric currentby moving magnets near a coil of wire.We need a source of energy to turn thegenerator:Burn fossil fuels?Nuclear reactions?Renewable energy?You will have to choose !