IB Environmental Systems and Societies

1. Topic 3.3
Energy Resources

2. Range of Energy Resources
• Renewable
– Solar
– Hydroelectric
– Geothermal
– Biomass
– Tidal
– Wave
• Non-renewable
– Coal
– Gas
– Oil
– Nuclear
Macro-scale
(country-wide schemes contributing to the
national grid)
Micro-scale
(domestic or within small communities)
http://www.youtube.com/watch?v=Gz_L6KuqvFI

3. Range of Energy Resources
• In 2004, global energy production was 500 exajoules (1
exajoule = 1 x 1018 J)
• Approximately 80% of this was derived from fossil fuels
• Fossil fuels provided the basis of the industrial
revolution (initially coal in Britain) and have been
depended on ever since
• Oil is (was?) plentiful, portable and readily distilled into
fractions such as petroleum and kerosene
• The advent of the combustion engine has cemented
our dependence on oil
• Crude oil is extracted in combination with natural gas
• The effects of fossil fuels on the environment were not
really considered until recently

4. Range of Energy Resources

5. Energy Consumption

6. Energy Consumption
• Per capita energy use in MEDCs is much higher
than LEDCs
• The economies of MEDCs are based on high
technology, high energy use, high fossil fuel
use
• The economies of LEDCs traditionally have less
available technology, greater dependence on
natural resources (wood and biomass
combustion), lower use of fossil fuels
http://www.youtube.com/watch?v=9qFKqDnGX0g

7. Energy Consumption

8. Energy Consumption

9. Energy Consumption
• Non-renewable resources are generally cheaper than
renewables
• Natural gas is cheap, relatively plentiful, can be burned
without refining, and is fairly clean (compared to other
fossil fuels)
• Non-renewables generally have high capital costs, may
be in the experimental stage and may be dependent on
unreliable natural phenomena (wind, waves, sun etc.)
• The use of renewables will increase in the future as
fossil fuels become depleted and less accessible –
prices and taxes on polluting fuels will increase

10. Renewable Resources
• Do not usually release
greenhouse gases (the
exception is biofuels –
which are in any case
carbon neutral)
• Do not release NOx and
SOx
• Small ecological
footprint (biofuel
cultivation is an
exception)
• Generally expensive to
exploit compared to
fossil fuels (high capital
and maintenance costs)
• Many technologies are
still in the
developmental stage
• Locations may be limited
due to politics, local
conditions and
reluctance of local
people (e.g. to live near
wind turbines)
Advantages Disadvantages

11. Hydroelectric Power
• Reliable source of
energy which can be
switched on and off
when needed
• Do not release NOx and
SOx or greenhouse
gases
• Creates artificial lakes
which are used as
recreational areas and
reservoirs
• Cheap to run and
maintain once built
• High capital costs
• Large areas must be
flooded, displacing
populations, destroying
farmland and altering
downstream ecosystems
• Increased downstream
erosion rates
Advantages Disadvantages

12. Tidal Power
• Reliable source of
energy
• Do not release NOx
and SOx or
greenhouse gases
• Cheap to run and
maintain once built
• High capital costs
• Locations are limited
by tidal range and
shape of the
coastline
• May interfere with
navigation routes
and wildlife
Advantages Disadvantages

13. Solar Power
• Reliable source of energy
• Do not release NOx and SOx
or greenhouse gases
• Cheap to run
• High capital costs and still
being developed
• Locations are limited by
availability of sunlight
• Storage of energy requires use
of expensive batteries which
may be polluting when
disposed of
• May be expensive to maintain
if things go wrong
• Components are expensive
and their extraction may cause
environmental damage
Advantages Disadvantages

14. Wind Power
• Reliable source of energy
• Do not release NOx and
SOx or greenhouse gases
• Cheap to run and
maintain (there is little to
go wrong with a wind
turbine)
• High capital costs and still
being developed
• Locations are limited by
availability of wind
• In many places there is
reluctance to live near
wind turbines due to
noise and perception that
they spoil landscapes
• May have effects on
wildlife, especially birds
Advantages Disadvantages

15. Biofuels
• Carbon neutral
• Do not release NOx and
SOx
• Do not require existing
technologies to be
replaced for their use (i.e.
the internal combustion
engine)
• As portable as existing
fossil fuels
• Produce greenhouse gases
when combusted
• Large ecological footprint
• Monoculture – therefore
often displace farmland
and poor communities
(also affecting food prices)
or destroy virgin forest or
other ecosystems
• Pesticide use represents
further risk to the
environment
Advantages Disadvantages

16. Combustion of Waste Materials
• Free resource (readily
available and represents no
depletion of natural capital –
although waste should be
minimised)
• May be burned directly or
used as a source of methane
from decomposition
• Burning of methane reduces
the effect of a potent
greenhouse gas that would
otherwise enter the
atmosphere
• Reduces pressure on landfill
sites and waste
transportation
• Produces greenhouse gases
when combusted
• Results in the production of
other harmful pollutants,
especially dioxins
Advantages Disadvantages
Renewable or non-renewable resource?

17. Geothermal Energy
• Free and readily available
resource
• Does not need to be
converted to other forms of
energy if used for heating
• May also be used to generate
electricity
• Simple technology with low
capital and maintenance
costs
• Does not result in any form
of pollution or have any
visible effects on the
landscape if used
domestically
• Generally restricted to volcanic
areas such as Iceland
Advantages Disadvantages

18. Fossil Fuels
• Cheap and plentiful (at
least in the past)
• Existing technology for
extraction and use
• Existing technology to
control pollution (to some
extent)
• Generally portable and
can be delivered over
long distances (coal is
perhaps an exception)
• No other sources are able
to generate as much
energy at the present
time
• Polluting (CO2, NOx, SOx)
• Unsustainable (by
definition, supplies are
limited)
• As resources diminish it
will become more difficult
and dangerous to extract
them
• Accidents cause severe
damage to ecosystems
• Open-cast mining causes
habitat destruction on
large scales
Advantages Disadvantages

19. Nuclear Power
• Does not produce
greenhouse gases
• Existing technology
• Produces large quantities of
energy
• Extremely energy efficient
(1kg of uranium produces
20000 x more energy than
1kg of coal)
• By-products may remain
radioactive for many
thousands of years (there are
unresolved problems of waste
disposal)
• Radiation exposure results in
death, severe forms of cancer
and DNA damage (genetic
effects are heritable)
• Accidents may cause severe
damage to human health and
ecosystems (there is high
associated risk)
• Uranium is a scarce and non-
renewable resource
• Planning is long and complex
Advantages Disadvantages

20. Factors Affecting Choice of Resource
MEDCs have much higher energy demands than LEDCs
http://www.youtube.com/watch?v=KtWoPZluI2E

21. Factors Affecting Choice of Resource
• GDP has a large say in which resources can be used or developed
• Historical basis (fossil fuel dependence is a hangover from the industrial
revolution, especially in those countries that participated in it)
• Greater car use in MEDCs leads to greater dependence on petroleum
• Low uptake of nuclear power in MEDCs due to perceived risk and
problems of waste disposal (France is an exception with 78% of electricity
generation from nuclear sources; USA 20%)
• Fossil fuels are often a cheaper option due to existing, readily available,
large-scale technology
• Humans are resistant to large-scale change especially when costs are
stable (recession can change this perception)
• There is some reluctance to change to renewables due to the perception
that they can spoil natural landscapes
• There is increasing awareness of the environmental damage caused by
fossil fuel use which is leading to greater acceptance of renewable
resource use
• Choice of resources is largely driven by government policy

22. Questions
1. Outline the range of energy resources
available
2. Evaluate the advantages and disadvantages
of two named renewable resources and two
named non-renewables
3. Discuss the factors that affect the choice of
energy resources by MEDCs and LEDCs