Unit 3 VCE Environmental Science: Area of Study 1 - Energy and Greenhouse gases. This presentation has some typical exam a review of some typical exam questions for this unit of work as well as a comparison of the Mortlake Gas fired power plant and the Macarthur wind farm.

1. VCE Environmental Science
Unit 3: AoS 1: Energy
SAC 1B: Fossil vs Non-Fossil
550 MW Gas at Mortlake Power Station
Versus
420MW Wind Energy at Macarthur Wind Farm

2. First a revision of the greenhouse effect:
• You need to know the terms absorption,
dissipation, electromagnetic, radiation,
transmission, reflection, ultra-violet, infrared
and visible light.
• You need to be able to draw a labelled
diagram of the natural and enhanced
greenhouse effects.

5. Question 1
Which of the following groups contains only
examples of renewable energy sources?
A. hydroelectric, coal, wind
B. nuclear, natural gas, solar
C. solar, wind, hydroelectric
D. hydroelectric, natural gas, wind

6. Question 2:
Considering the overall global effect, which
of the following gases is the most significant
contributor to the natural greenhouse
effect?
A. methane
B. water vapour
C. carbon dioxide
D. chlorofluorocarbons

7. Question 3
Which of the following gases has the
greatest impact globally on the enhanced
greenhouse effect?
A. methane
B. water vapour
C. carbon dioxide
D. chlorofluorocarbons

8. Question 4
Which of the following lists of energy sources are
in order of increasing emission of carbon
dioxide per unit of energy produced?
A. biomass, natural gas, coal, nuclear
B. biomass, natural gas, nuclear, coal
C. nuclear, biomass, coal, natural gas
D. nuclear, natural gas, biomass, coal

9. Question 5
Figure 1 shows the atmospheric concentrations of CO2 as
measured at a particular location over the period 1960–2008.
The percentage increase in atmospheric concentrations of CO2
from 1960 to 2000 is closest to
A. 12%
B. 17%
C. 19%
D. 22%

11. Question 6
Which of the following options best identifies the type of
incoming radiation?
ultraviolet visible infrared
A. S R Q
B. R Q S
C. R P S
D. S R P

12. Question 7
Which of the following options best identifies the
type of outgoing radiation?
ultraviolet visible infrared
A. X X Y
B. None Y X
C. Y X Y
D. none Y none

13. 1 tonne = 1000 kg
kilo (k) = 103
mega (M) = 106
A thermal electricity generating plant is powered by coal. Each
kilogram of the particular quality of coal used produces 5 MJ of
energy.
Question 9
Burning of coal in the boiler is the first step in the process of
generating electricity. This burning of coal in the boiler is best
described as
A. an exothermic reaction.
B. an endothermic reaction.
C. conversion of kinetic energy to heat energy.
D. conversion of chemical energy to mechanical energy.

14. 1 tonne = 1000 kg
kilo (k) = 103
mega (M) = 106
A thermal electricity generating plant is powered by coal. Each
kilogram of the particular quality of coal used produces 5 MJ of
energy.
Question 10
The boiler burns approximately 50 tonnes of coal per hour.
Which of the following is the best estimate of the coal energy used
per hour?
A. 2.5 × 109 MJ
B. 1.8 × 107 MJ
C. 2.5 × 105 MJ
D. 1.8 × 103 MJ

15. 1 tonne = 1000 kg
kilo (k) = 103
mega (M) = 106
A thermal electricity generating plant is powered by coal. Each
kilogram of the particular quality of coal used produces 5 MJ of
energy.
Question 11
When burning 50 tonnes of coal per hour, the output of the
electricity generator is 25 MJ per second. The percentage efficiency
of the whole power station is closest to:
A. 0.01%
B. 0.36%
C. 3.6%
D. 36%

16. Question 12
Name a fossil fuel energy source you have studied.
Name a non-fossil fuel energy source you have studied.
You should use these two sources in answering Questions 1a. to d.
You have been asked to design the electricity supply for a city of
100 000 people.
12a. Describe the steps involved in using your nominated fossil
fuel source to provide electricity to the homes and industries in
the city. (4 marks)
12b. Describe the steps involved in using your nominated non-
fossil fuel energy source to provide electricity to the homes and
industries in the city. (4 marks)

17. 12c. Outline some advantages and disadvantages of using your
nominated fossil fuel energy source to supply energy to this city.
(4 marks)
12d. Outline a strategy that could be used to reduce the impact of
your nominated fossil fuel energy source on the enhanced
greenhouse effect. Your answer should make reference to the
specific emissions of your nominated fossil fuel source. Your answer
could address either the process of using the fossil fuel energy
source or reducing the impact of its emissions.
(5 marks)

18. SAC 1B: A report in annotated poster or
multimedia format (recommended – either a
slideshow or website of about 15 pages).
Outcome 1: Describe the principles of energy
and relate them to the contribution of one
fossil fuel and one non-fossil energy source to
the enhanced greenhouse effect.

19. Your report should demonstrate:
• Your understanding of the following key knowledge – energy
efficiency of conversions, ways of increasing energy efficiency,,
heat, combustion, greenhouse effect, the interaction of energy with
greenhouse gases: energy absorption, re-emission, radiation and
dissipation by greenhouse gases
• The use of data in describing the scientific concepts associated with
energy including: energy conversions and energy efficiency;
transmission, absorption, radiation and dissipation; greenhouse
gases
• Methods of recording and processing information ie
Acknowledgement of sources of information (bibliography of
written and electronic sources). Make sure you include a References
page.

20. Performance Descriptor:
‘Comprehensive use of accurate data relating to energy
conversions and efficiency in the use of one fossil and
non-fossil energy source. Reasoned and articulate links
are made between the use of one fossil and one non-
fossil energy source and their level of contribution to
the enhanced greenhouse effect. A well developed
explanation of relevant international, national, state
and/or local strategies and protocols for reducing the
impact of fossil fuel energy sources is included.
Detailed analysis is evident in explaining and assessing
the effects of one fossil and one non-fossil energy
resource use on the environment and society.’

21. Mortlake gas-fired power plant

22. 550 MW Gas –fired Power Station
• 550 MW can power
about 550,000 homes
(assuming 1MW =
approx 1,000 homes),
which is roughly
equivalent to a city the
size of Perth or 50 times
the size of
Warrnambool.

23. Location
The Mortlake Power
Station Project is a
550 MW gas-fired
power station 12km
west of Mortlake in
South-Western
Victoria. The Origin
Board approved
construction of
Project on 4 July
2008.

24. Location
The site was chosen due
to a range of factors,
including its access to the
500kV high voltage
electricity transmission
line, well serviced state
highways and roads, the
suitability of the land for
construction and its
proximity to Origin’s gas
reserves in the offshore
Otway Basin. (good
accessibility)

25. Base vs Peak Load
• Due to be completed this year, the open cycle power
station will supply peaking power to Victorian homes in
times of high electricity demand. The project also
involves construction of a dedicated 83km gas pipeline
which is completed and will be ready for
commissioning to meet the power station’s needs.
• The underground natural gas transmission pipeline
runs through more than 80 properties and stretches
through the Timboon, Brucknell, Garvoc and Terang
districts. Along this route, some sites required
horizontal direct drilling which bores underground to
ensure the minimum environmental impact.

26. Improved Efficiency
Currently Mortlake
Power Plant is an “Open
cycle” generator, but has
the capacity to be
converted to a
“Combined Cycle” or Co-
Generation (Heat and
Power) plant in future.
Co-generation plants are more efficient because the heat is not
wasted but used for other purposes – for example: space heating in
some countries, drying fruit and vegetables or hot water for
cleaning.

27. Social and Economic Impacts
• The Mortlake Power Plant has provided employment
for 300 workers, including as contractors, during
construction. When it is fully operational it will provide
up to 30 full time positions.
• Multi-million dollar construction, with opportunities
for local businesses in the supply of goods and services
(eg accommodation, fuel, food, construction materials,
cleaning, equipment hire and security). Property prices
and rental costs in Mortlake have increased since
construction started.

28. Environmental Impacts
High efficiency natural gas-fired power stations
can produce up to 70% lower greenhouse gas
emissions than existing brown coal-fired
generators, and less than half that of the latest
technology black coal-fired power stations.
Increasing the use of natural gas as a fuel for
electricity generation will assist Australia to
reduce its greenhouse gas emissions. However,
natural gas is a fossil fuel and although we have
over 100 years supply at 2002 rates of use, it is a
finite resource.

29. Advantages of Gas
• Gas burns cleaner than the other fossil fuels such as coal and oil due to
the highly efficient combustion process, which produces very few by-
products that are released into the atmosphere as pollutants.
• Gas produces 70% less carbon dioxide emissions compared to other
fossil fuels.
• Due to the clean burning process, natural gas does not leave residues
like soot or ash when compared to coal.
• Gas offers a high heating value, approximately 24,000 Btu per pound.
• Utilising gas removes the need for large underground storage facilities
and reduces the possibility of soil contamination when compared with
oil and there is less chance of the need for large scale environmental
clean ups using natural gas.
• Gas is relatively inexpensive when compared to coal (saves money).
• Gas is considered to be a reliable form of energy production because the
pipeline system is not susceptible to bad weather conditions unlike the
transport of coal or oil, which is often moved by road or rail.
• Increased reliability over wind and solar power.

30. Disadvantages of Gas
• Gas is a highly flammable substance and it needs
to be produced in highly managed circumstances.
• Creating and managing the pipelines used to
transport natural gas can be costly.
• Gas is considered to be a non-renewable energy
source and will run out eventually if our current
usage levels continue.
• Gas is colourless, odourless and tasteless which
can make finding potentially hazardous leaks
difficult.

31. Macarthur Wind Farm
Power from a non-fossil energy source

32. Location
The wind farm area covers approximately 5,500
hectares of freehold agricultural land approx 16km
east of Macarthur, between Hamilton and
Warrnambool in South Western Victoria.

33. Location
• The 420MW Macarthur
Wind Farm Project is made
up of 140 wind turbines
located on three
properties that are
predominately used for
sheep and cattle grazing.
About 90km of tracks
service the wind farm site.
Construction commenced
in December, 2011.

34. Environmental benefits
The Macarthur Wind Farm will
save approximately 1.7 million
tonnes of greenhouse gases per
year from being emitted into
the atmosphere. It will
contribute to the Federal
Government's expanded
Renewable Energy Target which
aims to have 20% of the
country's electricity generated
from renewable sources by
2020.

35. Economic and Employment Benefits
The project will create up to 900
construction and manufacturing
jobs in the region, with up to
300 on-site jobs during the peak
construction period, and up to
30 full-time ongoing operations
and maintenance positions to
service the wind farm during its
25 year design life, providing
long term employment
opportunities and associated
benefits for local businesses and
services.

36. Social and Community benefits
• The on site workforce now numbers in excess of 350 and a
large majority of these employees have been drawn from a
100km radius of the site. Leighton Contractors and Vestas
are providing training opportunities for workers and
developing new skills that will be of significant benefit to
these workers in the future.
• AGL, Meridian Energy, Vestas and Leighton Contractors are
all contributing to various community projects, including
upgrading sporting facilities, augmenting health care
equipment, improved child care facilities and development
of public spaces. The communities of Macarthur and
Hawkesdale will see the benefits of these projects in the
coming months.

37. Advantages of Wind Power
• Clean – no greenhouse gas emissions
produced in operation
• Renewable – wind is a resource that will not
run out
• Can operate at night (unlike solar)
• Other industries can operate in the vicinity
(eg. Agriculture)

38. Disadvantages of Wind Power
• Cost – this is a $1 billion project, over ten years in
the planning.
• Much of the infrastructure (blades and turbines)
have been manufactured overseas and
transported here, at great cost.
• Wind is not a constant energy source and
therefore cannot be used for base-load power.
• Aesthetics – some people complain about the
changed appearance of the landscape.
• Noise – some people complain about the noise
from wind turbines.

39. Disadvantages of Wind Power
• Impact on native vegetation and habitat
• Bird kills and disruption of threatened species.
• Areas of cultural and historical significance
• Potential health impacts
• TV and radio interference
• What happens at the end of the 25 year life
span? (Decommisioning)

40. References
• http://www.originenergy.com.au/1376/Mortl
ake-Power-Station-Project
• http://www.agk.com.au/macarthur/index.php
/the-project/