ENERGY CHOICES AND
SECURITY
7.1
Applications and Skill
• Evaluate the advantages and disadvantages of different
energy sources
• Discuss the factors that affect the choice of energy
sources adopted by different societies
• Discuss the factors which affect energy security
• Evaluate an energy strategy for a given society
Energy Resources
• Energy security: the uninterrupted availability of energy
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sources at an affordable price
Energy poverty: a lack of access to modern energy services
Fuel poverty: when a low-income household is living in a
home that cannot be kept warm at a reasonable cost
Non-renewable energy sources: are finite, so as they are
used up the supply that remains is reduced
Renewable energy sources: can be used over and over
again – mainly forces of nature, usually cause little to no
environmental pollution
Energy mix: the relative contribution of different energy
sources to a country’s energy production/consumption
Energy Resources
• The demand for energy has steadily increased
• Fossil fuels dominate the world energy situation
Energy Resources
• Fossil fuels have varied impacts with both production and
use
• Coal has the largest impact overall due to both production and
being dirty
• Oil spills can cause large scale devastation
• Natural gas is considered the least impactful
Energy Resources
• Consumption of energy
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varies
Most MEDCs tend to
use a wide mix of
energy sources
Nuclear energy requires
high investment thus
limits its use
Renewable energy
tends to be a “rich
nation” option
Fuelwood is extremely
important where
electricity is not an
option
Renewable Energy
• Hydroelectric: 4 big nations
account for about 53% of the
global total
• China – 23.4%
• Brazil – 11.4%
• Canada – 10.4%
• USA – 7.6%
• Scope for large-scale
expansion is limited due to
most suitable locations are
already in use
• Small-scape development is
still possible
Renewable Energy
• Wind: world leaders are
China, USA, Germany,
and Spain – account for
about 67% of world total
• In recent years wind
energy has reached a
critical, self-sustaining
stage both in
development and as a
source of energy
Renewable Energy
• Biofuel: fossil fuel substitute
made from a range of agri-crop
materials such as oilseed,
wheat, corn, and sugar
• Blended with petrol and diesel
• Largest producers are USA,
Brazil, and China – reduces the
amount of oil consumption
• Increasing concern that biofuel
is not reducing environmental
damage
Renewable Energy
• Solar power: growing source
of global energy, but currently
only about 0.4% of all
electricity generated
• Global leaders: Germany,
Italy, USA, China, and Japan
• Produced in two ways:
• Photovoltaic systems – uses
solar cells
• Concentrated solar power
systems – uses mirrors and
lenses
Renewable Energy
• Geothermal energy: natural
heat found in the Earth’s crust
in the form of steam, hot
water, and hot rock
• USA is the world leader, but
this is only 0.4% of electricity
production
• Other countries include
Philippines, Italy, Mexico,
Indonesia, Japan, New
Zealand, and Iceland
Renewable Energy
• Tidal power: act like
underwater windmills
• More predictable than solar
and wind
• Infrastructure is less intrusive,
but start-up costs are high
• Only utility scale tidal system is
in north-western France
• Greatest potential in Canada’s
Bay of Fundy in Nova Scotia
Renewable Energy
• Wave energy: generators
placed on the ocean surface
• Energy levels determined by
strength of waves which varies
considerably
• Areas with the best potential
include western coasts of
Scotland, northern Canada,
southern Africa, Australia, and
the northwestern coast of the
US
• Still in the research stage
Oil: non-renewable advantages
• Compact, portable source of energy, relatively easy to transport
and store
• Used for most forms of mechanical transportation
• Flexible use – can be distilled into different fuel products
• Cleaner and easier to burn than coal
• Remains one of the most economical sources of energy
• Oil industry has been the source of much advanced technology
• Refining produces elemental sulfur as a by-product, used for
many industrial applications
• Well established global infrastructure
Oil: non-renewable disadvantages
• Non-renewable – takes millions of years to form
• Burning oil generates CO2, a greenhouse gas
• Oil contains sulfur, which, when burnt, forms sulfur dioxide and
sulfur trioxide – combined with atmospheric moisture to form
sulfuric acid, leading to acid rain
• Not as clean or efficient in use as natural gas
• Serious oil spills have occurred from super-tankers and
pipelines
• Locating additional reserves requires a high level of investment
Oil: non-renewable disadvantages
• Political instability of some major oil-producing countries and
concern about the vulnerability of energy pathway
• There are concerns that “peak oil” (the highest level of oil
production) is not far away
• The price of oil has risen significantly over the past decade
• Some oil is now being strip-mined in the form of tar sands,
which raises serious environmental concerns
Oil: advantages and disadvantages
• Reserve to production ratio: the reserve remaining at the
end of any year divided by the production in that year. The
result is the length of time that those remaining reserves
would last if production were to continue at that level
• Shale oil: oil extracted from reserves, sometimes
described as “tight oil” reserves, held in shales and other
rock formations from which it will not naturally flow freely.
Shale oil has become more accessible due to advances in
technology
Oil: advantages and disadvantages
• Strategic petroleum reserves are large reserves of oil held
by countries including the US and China to tide them over
for a few months or so if normal oil supplies are disrupted
• Energy pathways are supply routes between energy
producers and consumers, which may be pipelines,
shipping routes, or electricity cables
Oil Sands: environmental concerns
• Canada and Venezuela – huge deposits oil (tar) that could
be vital over the next 50 years as conventional oil fails
• Concerns:
• Takes almost 2 tonnes of mined sand to produce 1 barrel of
synthetic oil leaving lots of waste
• Takes about 3 times as much energy to produce a barrel of Albertaoil-sands crude as it does a conventional barrel of oil resulting in a
large amount of greenhouse gases being released in the process
Pros of Wind Power
• Renewable source of energy that can produce reasonable
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levels of electricity with current technology
Advances in turbine technology over the last decade have
reduced the cost per unit of energy
Suitable locations with sufficient wind conditions can be
found in most countries
Has reached the take-off stage both as energy source and
manufacturing industry
Flexibility in location – offshore wind farms increasing
Repowering (replacing old turbines with modern ones)
can increase the capacity of existing wind farms
Significant public support
Cons of wind power
• Concerns about the impact on landscapes as the number
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of turbines and farms increased
Not in my backyard protests staged by people concerned
about the impact to their property values
Turbine hum can be disturbing to both people and wildlife
Debate about the number of birds killed by turbine blades
TV reception can be affected by wind farms
Development has required significant government
subsidies – some argue that this money could have been
better spent
Many farms are in coastal locations where land is very
expensive
Concerns of Nuclear Power
• Possibility of power plant accident – radiation into air,
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land, sea
Radioactive waste disposal/storage – “high level waste” is
a small portion of the waste yet creates the largest
concern because it generates heat and corrodes all
containers
Rogue state or terrorist use of nuclear fuel for weapon
High construction and decommissioning costs
Seen as less “democratic” by some due to the genuine
risk and level of security required
Possible increase in certain types of cancer near power
plant
Advantages of Nuclear Power
• Creates zero greenhouse gas emissions
• Reduces reliance on imported fossil fuels
• Not as vulnerable to fuel price fluctuations as oil and gas
– uranium is relatively plentiful and mines are in politically
stable countries
• Recently, plants have demonstrated a high level of
reliability and efficiency
• Nuclear technology has spin offs in areas such as
medicine and agriculture
Factors affecting energy source choice
PHYSICAL:
• Deposits of fossil fuels are only found in limited locations
• Large-scale hydroelectric requires high precipitation, major
steep-sided valley and impermeable rock
• Large power stations require flat land and geologically stable
foundations
• Solar power needs a large number of days a year with strong
sunlight
• Wind power needs a high average wind speed throughout the
year
• Tidal power stations require a very large tidal range
• The availability of biomass varies widely due to climatic
conditions
Factors affecting energy source choice
ECONOMIC/TECHNICAL
• The most accessible and lowest cost deposits of fossil fuels
are invariably developed first
• Onshore deposits of oil and gas are usually cheaper to
develop than offshore deposits
• Potential hydroelectric sites close to major transport routes
and existing electricity transmission corridors are more
economical to build than those in less accessible locations
• In poor countries foreign direct investment is often essential
for the development of energy resources
• When energy prices rise significantly, companies increase
spending on exploration and development
• The level of technology expertise in a country may be a
significant factor in decision making
Factors affecting energy source choice
POLITICAL/CULTURAL:
• Countries wanting to develop nuclear electricity require
permission from the International Atomic Energy Agency
• International agreements such as the Kyoto Protocol can
have a considerable influence on the energy decisions of
individual countries
• Potential hydroelectric power on “international rivers” may
require agreements of other countries that share the river
• Governments may insist on energy companies producing
a certain proportion of their energy from renewable
sources
• Public perception in some countries may be firmly against
certain sources of energy
Variable energy patterns over time
The use of energy has changed in all countries due to a
variety of factors:
• Technological developments
• Increasing national wealth
• Changes in demand
• Changes in price
• Environmental factors – public opinion