ks3 energy. the ultimate energy source the sun is the ultimate source of all our energy. for...
Post on 18-Dec-2015
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KS3 EnergyKS3 Energy
The ULTIMATE energy The ULTIMATE energy sourcesource
The sun is the ultimate source of all our energy.
For example, we often get energy from beef:
BEEF comes from COWS,
COWS eat GRASS,
GRASS gets energy from the sun by PHOTOSYNTHESIS
The 9 types of energyThe 9 types of energyType 3 example sources
Heat
Kinetic (movement)
Nuclear
Sound
Light
Chemical
Electrical
Gravitational potential
Elastic potential
Energy changesEnergy changesTo describe an energy change for a light bulb we need to do 3 steps:
Electricity Light + heat
1) Write down the starting energy:
3) Write down what energy types are given out:
2) Draw an arrow
What are the energy changes for the following…?
1) An electric fire
2) A rock about to drop
3) An arrow about to be fired
Conservation of EnergyConservation of EnergyIn any energy change there is ALWAYS some “waste” energy:
e.g. a light bulb:
Electricity Light + heat
In this example HEAT is wasted – it’s given to the surroundings. Waste energy is virtually
always heat and it’s always given to the surroundings.
Heat transferHeat transfer1) Conduction – this is when heat is passed on through a solid by vibrations of particles:
2) Convection – this is when “heated stuff” moves somewhere else and takes heat with it:3) Radiation – this is when heat is moved by “heat waves” (infra-red) – this is how heat reaches us from the sun:
Power stationsPower stations
Cooling tower
Turbine
Generator
Transformer
Boiler
What does What does each part each part
do?do?
The boiler is where the fuel is burnt to boil water
The steam from the boiler is used to turn a turbine
The turbine is connected to the generator, which acts like a dynamo – it generates electricity out of movement
The steam is cooled down and turned back into water in the cooling tower
Renewable vs. non-renewable Renewable vs. non-renewable fuelsfuels
A ________ energy source is blatantly one that can be _______ (“renew = make again”), e.g. _____, solar power etc. Biomass is also an example of a renewable energy source – ______ is a form of biomass.
A ___________ energy source is one that when it has been used it is gone forever. The main examples are ____, oil and gas (which are called ______ ____, as they are made from fossils), and nuclear fuel.
Words to use – non-renewable, coal, wind, renewable, fossil fuels, wood, renewed
Non-renewable energy Non-renewable energy sourcessources
Coal, oil, gas and nuclear
Advantages Disadvantages
Cheap fuel costs
Short start-up time
Good for “basic demand”
Fuel will run out
Costs a lot of money to
decommission a nuclear plant
Pollution – CO2 leads to global warming and SO2 leads to
acid rain
Other ways of generating Other ways of generating electricity…electricity…
Can we drive the turbine without burning anything?
Other ways of generating Other ways of generating electricity…electricity…
Wind
TidalWave
Hydro-electric
Renewable energy Renewable energy sourcessources
Coal, oil, gas and nuclear
Advantages Disadvantages
Clean
Easily accessible
Won’t run out Very expensive
Energy is “dilute” – in
other words, it’s very spread out
Often depend on the weather – is it
sunny???