Energy revision – AS option module

Types of energy – renewable (flow) resources, non-renewable (stock) resources,
primary/secondary energy, the primary energy mix considered in a national context.
Renewable resources – resources that will not run out and which are
continuously being created. They include solar, wind, tide, hydroelectric and
geothermal power.
Flow resources – the result of a continuous flow like wind or tide.
Non-renewable resources – finite or limited resources, which will run out sooner
or later. They include fossil fuels like coal, oil and natural gas and also nuclear
because it uses uranium. Breeder reactors, which create their own fuel, are
theoretically possible but are not sufficiently developed.
Stock resources – there is a stock of each resource and when that stock is
gone it’s gone forever.
Fossil fuels
= http://www.discoveringfossils.co.uk/fossilfuels.htm
Primary energy – is released from a direct source, e.g. heat energy is released
from burning coal.
Secondary energy – when primary energy is converted in to a different form it
becomes a secondary energy, e.g. when heat energy form burning coal is used
to generate energy.
Resources have to be carefully managed if they’re to be considered to be
renewable, e.g. wood – techniques such as coppicing (traditional method of
woodland management in which young tree stems are repeatedly cut down to
near ground level) and replanting; geothermal – if the power station is too large
for the site and continually pumping water in to the ground it will end up cooling
the ground.
Primary energy mix – UK energy mix CASE STUDY

Global patterns of energy supply, consumption and trade. Recent changes in these patterns.
Some countries produce lots of energy because they have large energy
reserves and the money to exploit them.
Iran, Saudi Arabia – large oil reserves
UK, Russia, Canada – large oil and gas reserves
China, Australia – large coal reserves
USA, Indonesia – large coal, oil and gas reserves.
Some countries produce little energy because they have few resources or are
unable to exploit their resources due to lack of money or political instability.
Sudan – politically unstable and lack of money
Ireland – few recoverable resources
Key Figures:
Global energy consumption is unevenly distributed. A strong relationship
between GDP and energy consumption.
Wealthy countries tend to consume lots of energy per person because they’re
wealthy and can afford to. Most people in these countries have access to
heating and electricity and use energy intensive devices like cars.
Poorer countries consume less energy per person as they are less available to
afford it. Lifestyles are not dependent on it.
Some countries don’t consume much energy per person, but consume a lot
overall because they have a large population, E.g. Brazil consumes less
energy per person than Ireland, but has a higher total energy consumption.
Some countries don’t produce much energy but still consume a lot, and vice
versa. This is possible because energy is traded between countries.
1. Countries that are able to produce a lot of energy can export it to
those that can’t.
2. Canada, Saudi Arabia, UAE etc all export large amounts of energy.
3. Ireland, Italy and Japan all import large amounts of energy.
Trade in gas – developed as an economic fuel in the mid- 2othC. Transported
by pipeline or tanker. To move by tanker it needs to be cooled first.
3rd most important source of energy in the world.
It has the benefit of producing less atmospheric pollutants than either coal or oil.
Over last 10 years annual production worldwide increased by 2.5%
Most important trend is the increasing production in the USA and Russia.
Biggest new discoveries in the Middle East.
Trade in Coal – basis of industrial revolution in the UK in the 18-19thC.
Since 1950s European Coal industry has gone into rapid decline.
Deep mining of coal has almost completely ended in the UK, France and
Belgium.
Eastern Europe still mines significant quantities.
Decline in UK due to various factors including cheaper labour in S. Africa; all
easy accessible coal had been mined; remaining deposits to deep and faulted to
mine economically.
Changes in production
Energy production increased where new reserves have been discovered e.g.
Algeria
Angola is now more politically stable and increases have also taken place
Changes in consumption
China has largest population and one of fastest economies in the world. More
consumer demand for products therefore more energy usage increases.
NIC’s such as Malaysia using more energy as they develop.
Changes in trade
Exports from ex-soviet controlled countries such as Kazakhstan are increasing.
More attractive than the Middle East because the country is stable and not
controlled by Russia, this therefore reduces the dependence on these 2 areas.
Brazil and Denmark are now energy self-sufficient because of the development
of renewable resources and discoveries of oil reserves.

The geopolitics of energy – conflict and cooperation in world affairs. The role of transnational
coorportations in world energy production and distribution.
Energy security is an important issue for all governments for several reasons:
1. All countries dependent on energy supply;
2. Large reserves of oil and gases are in areas that are politically
unstable e.g. Russia, which means that energy supplies are often at
risk of being disrupted e.g GAZPROM and Ukraine.
(How important is Russia in the geopolitics of energy) CASE STUDY
– SEE YOUR INDIVIDUAL NOTES OR PAGE 242 – 245 IN AS (BLUE)
TEXT BOOK.
3. Global energy use is increasing and fossil fuels are decreasing.
Governments are trying to ensure that future energy supplies are
secure.
4. Agreements reached between exporting and importing countries e.g.
EU and Russia in 2000.
5. Conflict may arise when governments can’t agree. 2980 Carter
doctrine stated that the USA would use force in the Middle East to
protect its investment.
6. International agreements such as Kyoto Protocol to address the
impact that energy has on the environment.
7. Political ideologies have changed throughout the last 30 years which
means that there is a struggle for power in energy supplies.
Trans-National Corporations – companies that operate in more than 1 country.
Play a major role in world energy production and distribution.
Use your BP example – can also link to recent oil spill, Gulf of Mexico

Environmental impact of energy production – fuel wood gathering; nuclear power and its
management; the use of fossil fuels – acid rain; the potential exhaustion of fossil fuels.
Extraction of fossil fuels, e.g. by mining, can damage the environment.
Acid Rain
Burning fossil fuels releases various gasses. Some of these dissolve in water
vapour in the atmosphere, which then falls as acid rain. Acid rain can:
Kill fish which can lead to reduced biodiversity.
Kill trees and other plant life.
Reduce nutrient content of soil.
Corrode rocks, e.g. limestone.
Managing acid rain – use coal which contains less sulphur; washing coal before
it’s burned; burning other fuels in power stations; using other sources of electricity
beside fossil fuels;
Global Warming
Burning fossil fuels leads to an increase in the amount of carbon dioxide in to the
air. This enhances the planet’s natural greenhouse effect, increasing world
temperatures and causing climate change. This could lead to – rising sea levels
and increased flooding; more frequent and extreme weather events and habitat loss.
Oil Spills
Spills happen when pipes, oil wells or tankers transporting oil leak. The effects of
oil spills last a long time and lead to the death of the wildlife.
1. Oil reduces the ability of animals to move freely.
2. Hypothermia – feathers and fur are coated in oil.
3. Consumption of oil.
You can refer to the recent oil spill in the Gulf of Mexico
Fuelwood
Supplies 87% of the world’s energy. Many people in LEDC’s such as those in
Burkino Faso use wood as an energy source for cooking and energy within the
home. Wood that is burnt for fuel is called fuel wood. The gathering of fuel wood
damages the environment in various ways:
Deforestation – most fuelwood gathering isn’t regulated and can seriously deplete
local woodland;
Habitat loss – deforestation can damage or destroy the habitats of a wide range of
wildlife;
Soil erosion – tree roots bind soil together. If the trees are removed the soil isn’t
held together as well and can be washed or blown away by the wind.
BURKINO FASO – over 90% of the energy used for cooking comes from wood.
Consumption of wood is greater that the rate of growth, so there is no ecological
sustainability.
Alternative fuels are so expensive there is no alternative and no economic
sustainability. For a family to cook with containers of liquid costs 72 francs per
year, which is more than the average income of 45% of the population. One author
commented on the area that there may need to be a fuel aid given to these
countries as there was food aid packages.
Fuelwood crisis emerged at the same time as the oil crisis of the 1970s.
Agricultural policies introduced to make countries more self-sufficient in food
production. This was at the expense of existing forest lands.
Wood energy is not being exploited in a manner that is sustainable to African
countries.
Nuclear energy
Heat released from uranium or plutonium is used to generate electricity.
First commercial reactor opened in 1956.
439 nuclear reactors in 31 countries around the world.
Supply 15% of the world’s electricity = 6.3% of total energy consumption.
Advantages
Disadvantages
Low carbon dioxide emissions
Nuclear waste highly radioactive. Has
to be stored carefully for thousands of
years and is expensive.
Less toxic waste released into
Accidents causing radioactive waste to
environment than fossil fuel plants
leak in to the environment can have
devastating consequences e.g. human,
animal and plant deaths; illness;
destruction of the local environment
and contamination of large areas of
land. The damage lasts for a long
time.
Large amount of energy are generated
Only a limited amount of uranium and
from small amounts of fuel
plutonium so this makes it a non
renewable resource.
Electricity produced by nuclear power
Decommissioning power stations at the
is cheap
end of their life is very expensive.
Less venerable to shortages because
Breeder reactors need a feedstock of
of strikes, natural disasters or
uranium and thorium, so when we run
international tensions.
out of these two fuels (in about 1000
years) breeder reactors will cease to
be useful.
In France 78% of electricity is
Chernobyl - Ukraine
produced from nuclear power. France
1986
had the cleanest air of any
56 deaths – 31 as an immediate
industrialised country and the cheapest
result.
electricity in Europe.
Radiation released caused thousands
of deaths and illnesses.
Radioactive material detected as far
away as Ireland.
4km² area of forest around Chernobyl
destroyed
Food supplies (particularly fish) were
affected in Scandinavia for several
years after the accident and the
Chernobyl area is still heavily
contaminated today.
Estimated 15,000 more died in the
surrounding area after exposure to
radiation.
Independent Committee on Radioactive Waste
Management to look at nuclear waste
disposal and recommends :

Geological disposal as the end point in
the long term management of
radioactive waste

Geological disposal in an underground
repository is the waste management
option that is currently favoured by
many countries for spent fuel. No
country is yet operating a geological
repository for these materials but have
identified sites

Geological disposal is based on the
concept of retention of the waste
within a geological repository behind a
buffer of crushed rock, clay and grout.

Excavation would typically be to a
depth of 200-1000 metres in a variety
of rock types.
Also see: http://www.greenpeace.org.uk/nuclear
http://www.smh.com.au/business/saudi-push-for-power-20100418-smr3.html
http://www.guardian.co.uk/environment/nuclearpower

The potential for sustainable energy supply and consumption. Renewable energy, bio-mass,
solar power, wind energy, wave energy, tidal energy. Appropriate technology for sustainable
development.
Sustainable energy sources are always renewable.
For energy production to be sustainable it mustn’t deplete resources or cause
any long term environmental damage. Energy production using non-renewable
resources isn’t sustainable as it’s environmentally damaging and the resource will
one day run out. Energy produced from renewable resources is sustainable as it
doesn’t usually cause long term environmental damage and the resource won’t
run out.
Wind energy is responsible for 1% of the world’s electricity production. Carbon
dioxide is released during the production and installation of wind turbines but
once that’s done no greenhouse gasses are released and no fuel is needed.
Wind turbines are built in
open exposed areas
Disadvantages include:

where there’s a high
Wind energy is
chance of strong and
unpredictable.

regular
winds.
The
energy
of the wind
Large numbers of
turns the blades of the
turbines are needed
turbine, converting wind
to produce
energy to mechanical
significant amounts
energy, which is then
of electricity, which
converted to electrical
Large scale wind
energy by a generator.
power involves wind
takes up a lot of
space

The most
farms that may have
appropriate places
for turbines are
often protected
areas of natural
beauty

Wind farms
produce a constant
humming noise,
which some people
living nearby don’t
like

Turbines can kill or
injure birds and
bats
thousands of turbines.
The electricity
Small scale wind power
generated is fed in to
involves small turbines that
an electrical grid and
might be connected to a grid
transports electricity to
but often supply one building.
consumers. Wind farms
UK has built many small onshore wind farms but
can be both on/off
they don’t produce a large amount of electricity.
shore.
Suitable wind energy
farm locations are in the
remote highland regions where building, maintenance
and grid connections are high.
The future of UK wind power lies offshore because
of opposition from local people.
The biggest operating at present are Barrow and
Kentish Flats have a capacity to generate 90MW of
electricity.
London Array project

Up to 341 turbines, installed over 4 years
For more info on London Array:
http://www.londonarray.com/
http://www.telegraph.co.uk/news/u
knews/1537317/Windfarms-topower-a-third-of-London-homes.html
Biomass is material that’s burnt for power or used to produce biofuel.
Biomass is material that is or was recently living.
It includes wood, plants and animal waste.
These materials can be burnt to release energy.
Biomass can be processed to produce biofuels, which are then burnt to release
energy.
A common way of producing biofuel is to ferment sugar cane to produce alcohol,
which can then be burnt. Methane and biogas are also types of biofuel produced
using fermentation.
Using biomass as an energy source can involve a lot of technology (if biofuels are
being made) or very little (if biomass is being burnt directly). This means that
biomass is a suitable energy source for a wide range of countries.
Biomass energy is released by burning, which produces carbon dioxide. Biomass
doesn’t contribute to global warming though, as the amount of carbon released
equals the amount of carbon taken in when the material was growing. This means
there’s no overall increase in the amount of carbon dioxide in the atmosphere from
the burning of biomass.
Advantages
Disadvantages
The price of oil is rising
Land is being lost from food production
as it is turned to production of crops
like corn (maize) and oilseed rape,
which are grown in increasing
quantities. This could lead to increased
food prices or even food shortages. In
this case it is likely to be poor people
and poor countries that suffer first.
There is an impending shortage of oil
Production can lead to monocultures
and loss of traditional countryside.
A wide variety of crops can be used
Production on the necessary scale will
and much crop and food industry
almost certainly demand big inputs of
waste can also be converted
fertiliser and pesticides which, at
present, are mainly produced from oil-
based chemicals.
Biofuels only release carbon that has
been collected by photosynthesis as
the producer plants have grown.
Biofuels allow countries greater energy
supply.
BRAZIL
Been running an ethanol fuel programme since the 1970s. The ethanol is made by
fermenting sugar cane, and any leftover cane is burnt for heating and power.
Ethanol supplies 18% of transport fuel and cars either run on ethanol or a petrol
and ethanol mix. This has decreased Brazil’s dependence on imported oil.
Solar power
How Does Solar Power Work?
Solar energy is collected by photovoltaic ("photo-vol-tay-ick") cells which are made
(partially) of silicone, are installed in panels, and are placed in areas that receive a
lot of direct sunshine-- typically, a person's roof. When the sun beats down on
these photovoltaic cells, negatively charged neutrons are dislodged from the silicone
of each cell. These neutrons are trapped by a magnetic field and then harvested
by tiny wires in the silicone to form an electric current, which can then be put to
productive use. Contrary to popular belief, you don't have to live in a hot climate
to be able to use solar power; you just have to be in an area that receives a good
amount of sunshine.
Disadvantages of solar power include carbon dioxide released in equipment
production; PV cells are expensive and large areas of solar panels and sunny
climates are needed to produce large amounts of electricity.
Solar cookers work by concentrating sunlight, converting it to heat energy and then
trapping it for use in cooking.
Case study in text book
Tidal Energy
A reliable source of energy. Comes from the movement of tides.
Less variable than wind or solar energy as tides are regular, unchangeable events.
Tidal energy can be harnessed using tidal barrages or tidal stream systems. Tidal
barrages (dams) are built across estuaries. As the tide flows in and out water
passes through gates in the barrage, turning turbines that generate electricity. Tidal
streams are fast flowing currents caused by the tide. They turn turbines placed in
their pathway to generate electricity.
SEVERN BARAGE
The Severn Barrage is a proposed tidal power station to be built across the Bristol Channel (Severn
Estuary). The River Severn has a tidal range of 14 metres - the second highest in the world - making
it perfect for tidal power generation.
The 20 billion pound Severn Barrage would involve the construction of a 10 mile long barrage
(dam) between Lavernock Point south of Cardiff, Wales, and Brean Down in Somerset, England. The
barrage would act as a bridge between England and Wales and will have an operational lifetime of up
to 200 years. It would be the world's largest ever renewable energy project, and the UK's largest
engineering project since the Channel Tunnel.
Along the length of the Severn Barrage open sluice gates would allow the tide to flow in. These
gates would then be closed at high tide trapping enormous quantities of water behind the barrage.
A total of 214 40MW turbines would be built into the barrage through which the trapped water
would return at high pressure when the tide turns generating electricity. (In order to permit shipping
to pass through the barrage an enormous set of shipping locks would be constructed.)
The tidal turbines along the barrage would generate the same amount of electricity as three of the
latest nuclear power stations - 8.6 GW during flow and 2 GW on average. This would be sufficient to
provide 5-6% of the current electricity usage of England and Wales - equivalent to 8 large coal-fired
power stations.
Producing on average in excess of 17 billion kWh of electricity annually, the UK's carbon
emissions would be cut by 16 million tonnes each year (assuming Severn Barrage electricity replaced
electricity which would otherwise be generated in coal-fired power stations) which equates to 3% of
total current emissions.
A total of 200,000 man years of employment would be generated with a total of 35,000 jobs during
Wave energy
Harnessed by using a wave generator – a chamber with a hole at the top that
contains a turbine.
When a wave flows into the bottom of the chamber, the increased mass of water
forces air in the chamber upwards and through the hole, which turns the turbine.
The turbine is connected to a generator that produces electricity.
Disadvantages include: wave energy is unreliable, as there aren’t always waves and
the generators are expensive and making them release carbon dioxide in to the
atmosphere.
Hydroelectric power
Supplies about 20% of the world’s electricity and is responsible for over 60% of all
electricity from renewable resources. Once plants are built they release no
greenhouse gases.
As HEP plants dams are built to trap large volumes of water. Tunnels containing
turbines are luilt into dams.
The pressure of water above drives through the tunnels, turning the turbines.
Generators then convert this energy into electricity.
Disadvantages of HEP
Creating reservoirs can mean destruction of communities and habitats; If the dam
fails then large areas of land are likely to be flooded rapidly; ecosystems and fish
migratory paths are disrupted and the plants are expensive and making them
release carbon dioxide.
Appropriate technology is technology that’s suitable for the area.
Simple, low cost technologies. They’re made and maintained using local knowledge
and resources only, so aren’t dependent on any outside support, expensive
equipment or fuel.
Can contribute to sustainable development of they produce energy from renewable
resources.
SEE SOLAR POWER COOKING info

Energy conservation – designing homes, workplaces and transport for sustainability.
Energy supply can be made more sustainable by conserving as much energy as
possible. By reducing overall use of energy fewer resources are ised up and the
environmental effects of energy use are limited, e.g. emission by greenhouse gases.
Homes, workplaces and transport can all be designed to conserve energy.
Buildings can be made more sustainable:
1. Install double glazing, loft insulation, cavity wall insulation and
draught-proofing.
2. Installing energy efficient boilers.
3. Use computers, printers and faxes that turn themselves off after a
period of time.
4. Build in features that help absorb and retain the sun’s energy e.g.
south facing windows.
5. Using energy saving appliances wherever possible, e.g. energy saving
light bulbs
Transport
1. Changing to vehicles that don’t need any fuel, e.g. bicycles.
Employees receive tax benefits for loaning or selling bicycles as part
of the ‘Cycle to work’ scheme
2. Establishing out of town park and ride schemes and investing in
public transport. This can reduce fuel consumption.
3. Introducing congestion charges. This encourages public transport.
London congestion charge introduced in
2003.
Charges drivers for entering a central
zone of the city during normal working
hours.
Aims to reduce congestion and raise
money for public transport
improvements.
Since the scheme started the number of
vehicles within the zone has decreased
by 21%
Carbon dioxide emissions have
decreased by 20%
2007/08 £137 million was raised,
which was invested in public transport.
Bicycle use has increased by 12% since
2003
Use of public transport has increased by
6%
An increase in congestion in the area
surrounding the central zone and some
small businesses claim that the charge
Transport can also be made more sustainable by using technologies that run off
sustainable energy:

Hydrogen fuel cell buses run on electricity produced from hydrogen. The
hydrogen that fuels the bus is made from water. The process uses
electricity. So, for hydrogen fuel cells to be sustainable this initial electricity
must be renewable.

Electric buses

Using hybrid fuel vehicles (which run off a mixture of two fuels)

Case studies at national scale of two contrasting approaches to managing energy supply.
SEE Kenya, Iceland and UK