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Glossary for Unit 2
Energy generation CGP pg12-13
Renewable energy sources Non-renewable energy sources
Wind turbine Oil
Solar energy Gas
Tidal energy Coal
Hydroelectric energy
Biofuel
Nuclear power
Nuclear power; however, is a controversial form of power generation because although nuclear energy itself
is a renewable energy source, the uranium used in nuclear power plants is not:
For Against
• Nuclear power produces very few CO2 • They take a lot of energy, resources and
emissions in use money to build
• Uranium, which is used as the fuel, is an • They cost a lot to decommission
abundant resource and is unlikely to ever • Difficult storage of spent fuel which stays
run out radioactive for thousands of years
• Large amounts of power can be produced
which is easily controllable
• Relatively quick in terms of response time /
meeting demand
Fracking – is the process of extracting gas from shale, it involves drilling a well down into the earth’s crust
and then sending a high-pressure water, sand and chemical mixture into the rock to release the trapped
gas. The gas then travels back up the drilled shaft and is collected at the well head.
Energy storage CGP pg12-13
Pneumatics – another form of compression used to store gas or air under pressure, where movement is
controlled by using a system of valves, pistons and they are accurate, efficient and low maintenance.
Hydraulics – the gas or air in a pneumatics system can be swapped for a liquid, most commonly oil. This is
usually delivered through a type of pump called a compressor, most compressors have a storage tank where
the air or liquid is help under pressure ready to be used.
Flywheel – stores kinetic energy providing a continuous energy (something that will never run out or stop)
when the primary energy source is discontinuous, or delivers bursts of energy when required, by
accumulating stored energy in the flywheel over a period of time and releasing it when required.
Alkaline cells – alkaline batteries have a higher capacity for their size as the dense manganese oxide inside
them uses less space to produce the same power as a traditional acid based battery.
Rechargeable batteries – they are capable of being recharged hundreds of times reducing the quantity of
resources needed to produce new disposable batteries
, Statement / Question Answer
Pneumatic systems move compressed ______ to
Gas or air
create movement.
Batteries store which type of energy? Chemical energy
Fluid or oil pumped around a system under pressure is
Hydraulics
known as what?
Why do alkaline cells usually last longer than The dense manganese oxide inside of them uses less space
traditional lead-acid varieties? to produce the same power
A battery cell
Draw the circuit symbol for a cell and a battery. typically
provides 1.5 V
What energy is stored in a candle and what is it
Chemical energy into light and heat energy when burned
converted to when it is burned?
Justify the best times to pump water back up to an During periods of low demand. Less demand means that
upper reservoir at a kinetic pumped hydroelectric power being produced from other sources can be used
power station. more efficiently to load balance the grid.
Modern materials CGP pg38
Corn starch polymers – Corn-starch plastic products look and feel just like regular plastic, but they are
100% biodegradable and compostable. The natural bacteria in the soil break down the plastics very quickly
and unlike petrochemical based polymers, they are not toxic to the environment.
Flexible MDF – made from wood pulp fibred in the same way as standard MDF, with the addition of groves
cut across the width and length of the board allowing the board to be flexible.
Titanium – a very versatile metal which is usually alloyed with other metals to enhance its properties
Fibre optics – they allow digital information to travel as pulses of light along thin glass strands at very high
speeds
Graphene – a two-dimensional material, one atom thick but 200 times stronger than steel; it is transparent
yet impermeable, flexible and stretchable also being the most conductive material known. It is to be
developed but has potential uses in the medical, electronic and energy industries.
Liquid Crystal Displays (LCD) – they offer a low-cost and low-power method of displaying information
Nanomaterials – a material between 1-100 nanometres and has helped aid miniaturisation whilst
improving conductivity.
Why are biodegradable polymers CO2 neutral?
Biopolymers have the potential to cut carbon emissions and reduce CO2 quantities in the atmosphere:
this is because the CO2 released when they degrade can be reabsorbed by crops grown to replace
them: this makes them close to carbon neutral.
As the plant grows CO2 is absorbed by the plant, some energy is used during manufacture and
transportation and often during use, when the plant is disposed of, the carbon is returned to the
ground, some gases are released as the polymer decomposes.
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