Generating electricity methods

3. Boiler
Generator
Turbine
FUEL
Chemical
energy
Heat
energy
Kinetic
energy
Electrical
energy
Grid

4. Facts
• The fossil fuels are coal, oil and natural gas.
• They are fuels because they release heat
energy when they are burned.
• Fossil Fuels were formed from the remains of
living organisms millions of years ago.
• About three-quarters of the electricity
generated in the UK comes from power
stations fuelled by fossil fuels.

5. Advantages
•A major advantage of fossil fuels is their capacity to
generate huge amounts of electricity in just a single
location.
•Fossil fuels are very easy to find.
•When coal is used in power plants, they are very cost
effective. Coal is also in abundant supply.
•Transporting oil and gas to the power stations can be
made through the use of pipes making it an easy task.
•Power plants that utilize gas are very efficient.
•Power stations that make use of fossil fuel can be
constructed in almost any location. This is possible as long
as large quantities of fuel can be easily brought to the
power plants.

6. Disadvantages
•Fossil fuels are non-renewable energy resources.
•They are limited and they will eventually run out one day.
•Fossil fuels release carbon dioxide when they burn, which
adds to the greenhouse effect and increases global warming.
•Of the three fossil fuels, for a given amount of energy
released, coal produces the most carbon dioxide and natural
gas produces the least.
•Coal and oil release sulfur dioxide gas when they are burnt,
this then causes breathing problems for living creatures and
contributes to acid rain.

8. Fuel rods of uranium
and plutonium

9. Facts
• The main nuclear fuels are uranium and
plutonium, both of which are radioactive metals.
• Nuclear fuels are not burned to release energy.
Instead, heat is released from changes in the
nucleus.
• Just as with power stations burning fossil fuels,
the heat energy is used to boil water.
• The kinetic energy in the expanding steam spins
turbines, which drive generators to produce
electricity

10. Advantages
•Unlike fossil fuels, nuclear fuels do not produce carbon
dioxide.
Disadvantages
•Like fossil fuels, nuclear fuels are non-renewable
energy resources.
•If there is an accident, large amounts of radioactive
material could be released into the environment.
•Nuclear waste remains radioactive and is hazardous to
health for thousands of years. It must be stored safely.

12. Boiler
Generator
Turbine
FUEL
Chemical
energy
Heat
energy
Kinetic
energy
Electrical
energy
Grid

13. Facts
• Biofuels are fuels produced from plant material.
• For example, bioethanol is produced from plant
sugar and biodiesel is produced from plant oils.
• Unlike fossil fuels, biofuels are renewable
resources.
• In addition, their use may lead to an overall
reduction in emissions of carbon dioxide because
the growing plants absorb carbon dioxide from
the atmosphere.

14. Advantages
• Are cheaper than fossil fuels. Many governments are now
offering tax incentives to buy greener cars that run on biofuels
(ethanol being one example).
• Are considered ‘carbon neutral’ by some people.
• Reduces carbon emissions by 50-60%.
• Reduce dependence on foreign oils. Oil fluctuates in price
rapidly, so changing to biofuels will help buffer against the
change.
• Emit less particulate pollution than other fuels, especially
diesel.
• Are renewable sources of energy as you can just keep
producing more.
• Ethanol is very inexpensive to produce.
• Can help prevent engine knocking.

15. Disadvantages
• Setting aside land to grow biofuels means that there is
less land to grow food.
• It is also possible that food prices will rise as a result.
• More land must be set aside to make biofuels. Natural
habitats (flora and fauna) may be lost as a result.
• There are better solutions- such as using hydrogen fuel
cells.
• Not many gas stations have biofuels available at the
moment. This discourages people from buying cars that
are not reliant only on gas.
• Burning corn may release high concentrations of
nitrous oxide into the air, which is a greenhouse gas.

18. Facts
• Wind turbines (modern windmills) turn wind energy into
electricity.
• The wind is produced as a result of giant convection
currents in the Earth's atmosphere, which are driven by
heat energy from the sun.
• This means that the kinetic energy in wind is a renewable
energy resource: as long as the sun exists, the wind will too.
• Wind turbines have huge blades mounted on a tall tower.
• The blades are connected to a nacelle or housing that
contains gears linked to a generator.
• As the wind blows, it transfers some of its kinetic energy to
the blades, which turn and drive the generator.
• Several wind turbines may be grouped together in windy
locations to form wind farms.

19. Advantages
•Wind is free, wind farms need no fuel.
•Produces no waste or greenhouse gases.
•The land beneath can usually still be used for farming.
•Wind farms can be tourist attractions.
•A good method of supplying energy to remote areas.
•Wind power is renewable. Winds will keep on
blowing, it makes sense to use them.

20. Disadvantages
• The wind is not always predictable - some days have no wind.
• Suitable areas for wind farms are often near the coast, where
land is expensive.
• Some people feel that covering the landscape with these
towers is unsightly.
• Can kill birds - migrating flocks tend to like strong winds.
However, this is rare, and we tend not to build wind farms on
migratory routes anyway.
• Can affect television reception if you live nearby.
• Can be noisy. Wind generators have a reputation for making a
constant, low, "swishing" noise day and night, which can
annoy people.

23. Facts
• The water in the sea rises and falls because of
waves on the surface.
• Wave machines use the kinetic energy in this
movement to drive electricity generators.

24. Advantages
•Wave power is a renewable Energy Source.
•Wave Energy Is a Clean Fuel.
•Wave Energy is Environmentally Friendly - it doesn't destroy
the environment.
•There is plenty of it.
•Tides/Waves are always predictable.
•You can always produce a significant amount of energy.
•You don't need fuel so it doesn't cost that much .
•Waves are free and will not run out so the cost is in building
the power station.

25. Disadvantages
• It can cost a lot of money and requires further research.
• If the whole tidal/wave energy scheme does get popular real
estate will be losing money for beach front houses since they
will be using the beaches for the tidal/wind farms.
• It depends where you put it for the costs so not much good
financially
• May interfere with mooring and anchorage lines commercial
and sport fishing.
• Waves can be big or small so you may not always be able to
generate electricity.
• You need to find a way of transporting the electricity from the
sea onto the land.

28. Facts
• To make electricity this way, the water is held in a
reservoir, behind the dam.
• The water close to the control gates is where the
intake is, and when the control gates open, the water
rushes through the penstock and turns the turbine.
• After the water does so, it goes through the outflow
into the river.
• The turbine spins the generator, and the electricity
goes to the transformer in the powerhouse.
• Then the transformer transforms the electricity into a
usable form, and the electricity travels through the
power lines and goes to homes and businesses.

29. Advantages
• Once a dam is constructed, electricity can be produced at a
constant rate.
• If electricity is not needed, the sluice gates can be shut,
stopping electricity generation.
• Dams are designed to last many decades and so can
contribute to the generation of electricity for many years.
• The lake that forms behind the dam can be used for water
sports and leisure / pleasure activities. Often large dams
become tourist attractions in their own right.
• The build up of water in the lake means that energy can be
stored until needed, when the water is released to produce
electricity.
• When in use, electricity produced by dam systems do not
produce green house gases. They do not pollute the
atmosphere.

30. Disadvantages
• Dams are extremely expensive to build and must be built to a
very high standard.
• The flooding of large areas of land means that the natural
environment is destroyed.
• People living in villages and towns that are in the valley to be
flooded, must move out.
• The building of large dams can cause serious geological
damage.
• Although modern planning and design of dams is good, in the
past old dams have been known to be breached. This has led
to deaths and flooding.
• Dams built blocking the progress of a river in one country
usually means that the water supply from the same river in the
following country is out of their control.
• Building a large dam alters the natural water table level.

33. Facts
• Solar cells are devices that convert light energy directly into electrical
energy.
• Larger arrays of solar cells are used to power road signs in remote
areas.
• Solar panels do not generate electricity, but rather they heat up
water.
• They are often located on the roofs of buildings where they can
receive heat energy from the sun.
• Cold water is pumped up to the solar panel, there it heats up and is
transferred to a storage tank.
• A pump pushes cold water from the storage tank through pipes in the
solar panel. The water is heated by heat energy from the sun and
returns to the tank.
• In some systems, a conventional boiler may be used to increase the
temperature of the water.

34. Advantages
•Solar energy is a renewable energy resource
•There are no fuel costs.
•No harmful polluting gases are produced.
Disadvantages
•Solar cells are expensive and inefficient, so the cost of
their electricity is high.
•Solar panels may only produce very hot water in very
sunny climates, and in cooler areas may need to be
supplemented with a conventional boiler.
•Although warm water can be produced even on cloudy
days, neither solar cells nor solar panels work at night.

36. Grid
turbines
7Km

37. Facts
• Several types of rock contain radioactive
substances such as uranium and plutonium.
• Radioactive decay of these substances releases
heat energy, which warms up the rocks.
• In volcanic areas, the rocks may heat water so
that it rises to the surface naturally as hot water
and steam.
• Here the steam can be used to drive turbines and
electricity generators.
• This type of geothermal power station exists in
places such as Iceland, California and Italy.
...

38. Hot rocks
• In some places, the rocks are hot, but no hot
water or steam rises to the surface.
• In this situation, deep wells can be drilled
down to the hot rocks and cold water pumped
down.
• The water runs through fractures in the rocks
and is heated up.
• It returns to the surface as hot water and
steam, where its energy can be used to drive
turbines and electricity generators

39. Advantages
•Geothermal energy is a renewable energy resource and
there are no fuel costs.
•No harmful polluting gases are produced.
Disadvantages
•Most parts of the world do not have suitable areas where
geothermal energy can be exploited.

40. Wind Power
(Scottish highlands)
• We have plenty of highlands where the wind turbines can
be placed and gather a lot of energy, which can then be
generated into electricity to provide to many households
and other buildings. It is also more efficient in this country
than others, also the waste products are low and people
can live with the sound.