ANALYSIS OF THE POTENTIAL FOR WIND AND SOLAR ENERGY SYSTEMS IN ...

ANALYSIS OF THE POTENTIAL FOR WIND AND SOLAR ENERGY SYSTEMS IN ANTARCTICA
Christopher Brown, Antoine Guichard, David Lyons
IASOS (Institute of Antarctic and Southern Ocean Studies)
University of Tasmania, GPO Box 252-77, Hobart TAS 7001, Australia.
Phone: +61 3 6226 2971, Fax: +61 3 6226 2973
Electronic Mail: enquiries@iasos.utas.edu.au
ABSTRACT
of central Australia. These sites (consisting of isolated
ranger stations, homesteads and Aboriginal out-stations)
As renewable energy generation devices become more
currently operate using diesel generator sets, or natural gas
efficient and less expensive, the market for providing power
turbines, depending on fuel availability. An increasing
to remote communities is expanding. Power for these sites
number of these sites are now turning to wind and solar
is usually provided by diesel generator sets although, with
energy generation, often combined with battery storage, to
high winds or solar radiation levels, wind-turbines and solar
reduce the amount of fuel used. Preliminary indications
arrays could prove an ideal alternative. This is especially
suggest that these hybrid systems are cost effective, a result
true for Antarctica.
that will encourage further expansion (1).
The Australian Antarctic Division currently ships
Supplemental use of Solar and Wind energy at grid
approximately 750,000 litres of diesel fuel annually to each
extremities is also gaining attention in parts of Australia.
of three continental stations located on the coastline of East
At Kalbarri, located 600 km to the north of Perth on the
Antarctica. These operations are expensive and savings
coast of Western Australia, a 20 kW photovoltaic system
could be expected from the introduction of a renewable
has been installed, providing not only local power
energy generation capability. These stations experience
generation, but also voltage regulation (2). Wind
strong winds with gusts recorded at up to 81 m/s, together
generation has also had success at Esperance in Western
with temperatures often plunging below -30oC in winter.
Australia where a number of units have been installed to
This, while providing adequate meteorological conditions
supplement the local grid. The scope for similar grid
for power generation by wind-turbines, also imposes harsh
connected renewable power systems is expected to increase
design criteria. Solar also remains an extremely promising
dramatically in the next few decades as costs continue to fall
alternative during the summer, but is not viable for the
(3).
winter.
The Australian Antarctic stations currently rely on diesel
As part of a project investigating 'Alternative Energy for
generator sets and boiler systems to provide electrical and
Antarctic Stations', analysis of meteorological data has
thermal energy. The introduction of renewable energy
given wind energy capacity factors estimates of up to 0.7,
generation and storage systems at these sites has been
and summer solar energy capacity factors estimates of up to
suggested as a method to reduce costs and lower
0.3. These, combined with station load measurements,
environmental emissions. Wind energy (and solar energy to
have been used to determine the optimal sizing of the
a lesser degree), were suggested as offering the best
number and ratio of wind/solar to storage devices. Results
opportunities to achieve these goals (4).
indicate that installation of a 110 kW wind turbine capacity
at Mawson would result in a 25% fuel saving, while a 55
To determine the practicality of introducing wind and solar
kW wind turbine capacity at Macquarie Island would reduce
power generation systems to the stations, investigations
fuel consumption by 30%.
into the following areas have been initiated (results from
numbers 1 and 2 are presented in this paper):
1. INTRODUCTION
1. Assessment
- wind resources
A market niche that is particularly well suited to wind (and
- solar resources
solar) energy generation systems is the provision of
- station energy needs
electrical power to isolated communities. Remote Area
2. System identification and sizing
Power Supply (RAPS) systems have been installed
- wind / solar / diesel systems
extensively throughout remote areas of rural Australia,
- storage options
providing power to communities ranging from 50 kW to
3. Testing
1 MW. Examples of this include the Northern Territory
- survival criteria
Power and Water Authority (PAWA) which currently
- reliability and maintainability
services some sixty remote sites scattered across the top end
4. Costing

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2. AUSTRALIAN ANTARCTIC STATIONS
administration offices), the Science building (housing
equipment for active research projects into fields such as
The Antarctic stations operated by Australia are situated in
radio astronomy, upper atmosphere physics and biology)
some of the most isolated and inhospitable locations on
and the Workshop (providing an indoor heated area for
earth. Three permanent winter stations - Casey, Davis and
mechanical repair and maintenance, and work areas for
Mawson - are maintained on the Antarctic continent through
electricians, plumbers, and carpenters).
ANARE (Australian National Antarctic Research
Expeditions). A fourth permanent winter station is also
The energy systems of the stations are designed to provide a
operated in the sub-Antarctic on Macquarie Island, mid-way
safe, efficient and above all, reliable supply of electrical and
between the southern tip of Tasmania and the Antarctic
thermal energy. Energy is needed in order to maintain the
continent. The location of the four Australian stations
array of scientific programs operated at each station and
together with their shipping distances from Hobart ia given
provide suitable comfort conditions for expeditioners over
in Table 1.
the long, cold, dark, winter months. The current energy
system of the Australian Antarctic stations meets the power
Supply to the stations is restricted to the brief Antarctic
needs through the use of co-generation systems comprising
summer when sea ice conditions allow access to the stations
diesel generator sets and oil-fired boilers.
by ship for dry cargo transfer and refuelling. Currently, the
research/ressupply vessel Aurora Australis is chartered for
The main power houses of the continental stations consist
this purpose, supplemented every three year by a dedicated
of four 125 kVA Caterpillar 3306 diesel engines coupled
cargo ship. Typically 6 to 7 voyages are made every season
with matching alternator sets. Two to three engines are
resulting in 2 to 3 calls at each station. One visit to each
typically engaged at any one time to meet station load
of the stations is used for re-supply and refuelling, with the
demands. Heat recovered from the engines and
other visits used for personnel change-overs. Time and
supplemented by oil-fired boilers is pumped throughout the
space aboard the ships is at a premium. Marine Science
station to most buildings to meet thermal energy needs,
programs also require extensive use of the Aurora Australis,
although some buildings use their own independent heating
one of only a handful of vessels currently devoted to
systems. At Macquarie Island a much milder climate,
research on a regular basis in the waters surrounding
combined with more traditional building methods and lower
Antarctica, an area immense in size and resources. The
population levels, has resulted in much lower power
introduction of on-site power generation would have
demands. Two generator units are maintained in the main
considerable advantages over the current system, lowering
powerhouse at the station, with a single unit operated to
time and costs associated with refuelling the stations.
satisfy power demands at any one time. Efficiencies of 35%
(electrical) and 32% (thermal) have been reported for the
The stations themselves are large, modern, extremely well-
generators, and 80% (thermal) for the boilers (5).
equipped facilities, extensively rebuilt and upgraded during
the 1980s and 1990s, and represent an enormous investment
Assessment of the potential for wind and solar energy
by Australia in the region. Each continental station
generation at the stations will consists of three components:
consists of a collection of approximately 10 to 15
identification of wind reserves, identification of solar
buildings, designed especially for the expected conditions.
reserves, and finally estimation of stations energy needs.
The largest building at each station is the Domestic
Although thermal energy production levels at the stations
building, comprising recreation/sleeping/eating and medical
are of the same order as electrical production levels, this
areas - and as such - is the focus of station life after working
paper will concentrate on electrical energy production, as
hours. Other main buildings on station occupied regularly
exact quantification of the thermal needs (as apposed to
include the Operations building (housing all radio
production), has yet to be determined.
communication equipment and workshops, meteorology and
Station
Latitude
Longitude
Distance to
Hobart
Casey
66o17' S
110o32' E
3,427 km
Davis
68o35' S
77o58' E
4,816 km
Mawson
67o36' S
62o52' E
5,447 km
Macquarie Island
54o30' S
158o56' E
1,495 km
Table 1: Australian Antarctic station locations and shipping distances from Hobart

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2.1
Wind energy resources

extremes in temperature and wind speed recorded at the
stations is given in Table 2.
Antarctica has the distinction of being the highest, coldest,
driest and windiest continent on earth. Climatic conditions
While the maximum winds encountered at the stations are
at the stations are harsh. Blizzards periodically blast the
very high, the average winds are much lower. High winds,
continental stations, often resulting in very high wind
averaging above 30 m/s over a ten minute interval, were
gusts. Continuous low temperatures also occur at the
found to account for at most 5% of all observation made
continental stations, with summer temperature rarely above
over the last five year at Mawson and Casey, and even less
0oC and never above 10oC. Macquarie Island, situated north
at Davis and Macquarie Island. Resolution of the wind into
of the Antarctic convergence zone, has warmer weather with
bins, each 2.5 m/s wide, has been presented in Figure 1,
temperatures often above zero and never falling below -
indicating the relative frequency distribution of winds at
10oC. This however results in an extra phenomenon rare at
each of the stations. Weibull functions have been set to
the other stations - rain! Fierce winds also lash the island,
these distributions using weighted least-squares techniques
situated in the middle of the Southern Ocean in the
with the scale parameter c and shape parameter k, calculated
infamous ‘furious fifties’, creating extremely windy and wet
using the method described by Justus (6).
gales that saturate the island. A summary of the climatic
Site
Maximum recorded
Minimum recorded
wind gust (m/s)
temperature (oC)
Casey
80.8
-41.0
Davis
57.1
-40.0
Mawson
68.9
-36.0
Macquarie Island
51.4
-8.9
Table 2: Extreme climatic conditions recorded at the stations (7)
Casey
Davis
0.4
0.4
0.3
c = 6.2
0.3
c = 5.6
k = 1.5
k = 1.6
0.2
0.2
0.1
0.1
0
0
0
10
20
30
40
0
10
20
30
Mawson
Macquarie Island
0.4
0.4
0.3
c = 13.0
0.3
c = 10.8
k = 1.8
k = 2.5
0.2
0.2
0.1
0.1
0
0
0
10
20
30
40
0
10
20
30
40
Wind speed [m/s]
Wind speed [m/s]
Figure 1: Frequency−of−occurence of wind speeds 1990−94

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The mean wind speed, giving an indication of the potential
during the afternoon in summer when winds drop to an
for power generation, was calculated for the stations and is
average of 6 m/s.
presented in Table 3. To construct these figures,
observations recorded by the Australian Bureau of
Macquarie Island experiences the second highest average
Meteorology (BoM) over last five years were used. These
winds, consistently averaging approximately 9 m/s
observations consist of 10 minute averages taken
throughout the day, increasing to just over 10 m/s during
immediately before the hour, every three hours, starting at
periods of the equinoctial gales. These occur in March and
midnight UTC.
September whipping up winds into gales, encircling the
southern hemisphere in a broad latitude band encompassing
There are however differences in the mean wind speed over
the Island.
the year and over the day. The best method to indicate these
changes is in the diurnal mean wind speed calendar of
The average winds reported at Casey and Davis are much
Figure 2, intended as a guide to the expected wind resources
lower. At Casey winds average up to 8-9 m/s during the
at the stations for a particular month at a particular time.
winter months, dropping to 6 m/s over the summer. For
Davis, wind speeds average around 5 m/s for most of the
Mawson, which experiences strong katabatic air flow off the
year, except for early morning summer when the wind speed
polar ice cap, is continuously blasted by winds averaging
average increases to 7-9 m/s.
between 12-14 m/s, except for a period of relative calm
Station
maximum
mean
standard
wind speed
wind speed
deviation
(m/s)
(m/s)
(m/s)
Casey
49.4
7.15
7.88
Davis
28.8
5.07
4.15
Mawson
39.1
11.15
6.95
Macquarie Island
28.8
9.45
4.13
Table 3: Wind-speed statistics using 10 minute BoM 3-hourly observations 1990-94 (8)
Casey
Davis
24
24
20
20
16
16
12
12
8
Hour of day
8
4
4
0
0
D J F M A M J J A S O N D
D J F M A M J J A S O N D
Mawson
Macquarie Island
24
24
20
20
16
16
12
12
8
Hour of day
8
4
4
0
0
D J F M A M J J A S O N D
D J F M A M J J A S O N D
Month of year
Month of year
4
6
8
10
12
14
mean wind speed [m/s]
Figure 2: Wind speed annual and diurnal mean 1990−94

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Monthly wind capacity factor estimates, based on the
0.6 and 0.7 are indicated for most of the year, except for a
reported performance curve of the UM-70X using wind
small decrease during the summer months. Macquarie
frequency-of-occurrence measurements (see Figure 1), are
Island capacity factors are also high over most of the year,
presented in Figure 3. These capacity factors represent the
especially during the equinoctial periods. Casey and Davis
ratio of the expected output of the machine against its rated
indicate capacity factors at only 0.2 to 0.3, half that at
output. At Mawson, high wind capacity factors between
Mawson and Macquarie.
Casey
Davis
1
1
0.8
0.8
0.6
0.6
0.4
0.4
Capacity−factor 0.2
0.2
0
0
D J F M A M J J A S O N D
D J F M A M J J A S O N D
Mawson
Macquarie Island
1
1
0.8
0.8
0.6
0.6
0.4
0.4
Capacity−factor 0.2
0.2
0
0
D J F M A M J J A S O N D
D J F M A M J J A S O N D
Month
Month
Figure 3: Estimated monthly wind capacity factors 1990−94
2.2
Solar energy resources

1973 to 1977 for Casey, from 1968 to 1993 for Macquarie
Island; while for Mawson, totals are based on recordings
Clear skies, frequent in Antarctica, offer the potential to
conducted over an 18 month period from 1961 to 1963 by
supplement power from wind turbines with solar power
Weller (10). Unfortunately no data was available for Davis.
using photovoltaics. Cloud cover in the latitude 60oS band
in Antarctica is characteristically U-distributed, with either
This data is only available on a monthly basis. To obtain
complete cloud cover or no cover at all (9). This, combined
daily and hourly solar radiation levels an empirical model
with high albedo values due to snow cover, lack of moisture
has been used. This model incorporates an empirical
in the dry, dust free pristine air over the continent and long
relationship between solar altitude and incident radiation
daylight hours during the summer months, provides for
level, modified by an extinction factor calculated from cloud
extremely high insolation rates at the continental stations.
measurements (11). Comparison with the recorded monthly
These conditions unfortunately only occur during the
reading indicated agreements to with 10% for global
summer months, precluding the use of photovoltaics in
radiation estimates and 20% for diffuse radiation estimates;
winter. Conditions at Macquarie Island are not as
values deemed sufficient for our purpose. The estimated
constructive, with high cloud cover occurring for most of
diurnal and seasonal average solar radiations incident at the
the year reducing incident solar insolation levels.
stations are presented in Figure 5.
Monthly averages of the daily global and diffuse radiation
(Note: the inclination angle of the photovoltaic panel was
levels recorded at Casey, Mawson and Macquarie Island are
set to 60o on the continent, and 40o at Macquarie Island -
presented in Figure 4. These averages are based on the
calculated to maximise exposure rates from model
information available. Data was provided by the BoM from
simulation runs).

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Daily average
Yearly total
10
1250
8
Casey
1000
6
750
4
500
[kWh/m2]
[kWh/m2]
2
250
0
0
D
J
F
M
A
M
J
J
A
S
O
N
D
Diffuse
Global
10
1250
8
1000
Mawson
6
750
4
500
[kWh/m2]
[kWh/m2]
2
250
0
0
D
J
F
M
A
M
J
J
A
S
O
N
D
Diffuse
Global
10
1250
8
1000
Macquarie Island
6
750
4
500
[kWh/m2]
[kWh/m2]
2
250
0
0
D
J
F
M
A
M
J
J
A
S
O
N
D
Diffuse
Global
Figure 4: Monthly recorded solar rdiation levels
Casey
Davis
24
24
20
20
16
16
12
12
8
Hour of day
8
4
4
0
0
D J F M A M J J A S O N D
D J F M A M J J A S O N D
Mawson
Macquarie Island
24
24
20
20
16
16
12
12
8
Hour of day
8
4
4
0
0
D J F M A M J J A S O N D
D J F M A M J J A S O N D
Month of year
Month of year
0
100
200
300
400
500
600
700
800
mean solar radiation flux density [W/m2]
Figure 5: Solar Radiation annual and diurnal mean 1990−94

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Average solar insolation levels are extremely high during
turbines will be used. The solar capacity factor, defined as
the summer period centred about mid-day. The general
the ratio of the expected output of the cell to the rated
difference between the best solar power and wind power
output of the cell under cloud free solar insolation levels of
production times, offers promising potential for mixed
1 kW/m2(for which panels are rated), was calculated for the
systems. This is clearly evident for Mawson, where times
stations and is presented in Figure 6.
of high solar insolation almost perfectly coincide with the
reduced summer mean wind speed.
High returns (useable power production for a given installed
solar power capacity) are evident over the summer at each of
Expected solar energy conversion efficiencies for
the continental stations over a seven month period,
photovoltaics typically range from 10% in production line
beginning of September and ending March. Macquarie
cells to up to 23% in new-generation experimental cells.
Island returns are approximately 30-40% lower than on the
To gain an indication of the performance of these cells at
stations, although winter insolation levels are higher.
the stations, a term analogous to the capacity factor of wind
Casey
Davis
0.5
0.5
0.4
0.4
0.3
0.3
0.2
0.2
0.1
Solar capacity factor
0.1
Solar capacity factor
0
0
D J F M A M J J A S O N D
D J F M A M J J A S O N D
Mawson
Macquarie Island
0.5
0.5
0.4
0.4
0.3
0.3
0.2
0.2
0.1
Solar capacity factor
0.1
Solar capacity factor
0
0
D J F M A M J J A S O N D
D J F M A M J J A S O N D
Month
Month
Figure 6: Estimated solar capacity factors

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2.3
Station energy demands

energy production levels met by the diesel generator sets are
given below in Table 6.
Electrical and thermal energy demands at the stations are
high, requiring the use of large quantities of fuel. Table 4
To obtain an indication of the inter-daily and intra-daily
and Table 5 indicate the quantity of fuel and used in the
variation in electrical power, recordings of 10 minute
generator sets and boilers at each station over the last four
averages of the power were initiated. A daily cycle of
years.
between 20-30 kW was identified at Davis station,
superimposed onto a day-to-day varying base load averaging
Costs associated with shipping and handling cargo to
approximately 220 kW over the year.
Antarctica effectively triples the end price per litre of fuel.
Exact costs are hard to assess, but current estimates place
Using regression analysis based on a method described by
the unit price per litre at $1 (AUD) (5). This high cost has
(13), this load was resolved into components correlated with
further focused attention to the possibility of on-site power
station population numbers, air temperature gradients and
generation from renewable sources.
wind speed. Results indicate the power load is heavily
correlated with station population numbers and outside
The introduction of renewable systems would also have the
ambient air temperature. Wind induced loads were identified
added advantage of reducing the overall emission levels of
as having a low correlation with power loads. The
the stations, the most prominent local pollutant source in
remaining base load was found to be fairly constant, with
the near pristine air over the continent - important for
only a 20-30 kW seasonal variation.
scientific and environmental reasons. Reduced fuel handling
also will reduce the risk of fuel spillage, another major
concern in the fragile Antarctic environment. The electrical
Site
Yearly diesel use by generator sets (kl)
1992
1993
1994
1995
Casey
584.8
538.0
483.4
447.2
Davis
526.5
535.3
646.4
561.4
Mawson
630.4
607.5
629.8
652.8
Macquarie Island
202.1
173.7
168.4
174.4
Table 4: Total diesel usage in generator sets 1992 - 95 (12)
Site
Yearly diesel use by boilers sets (kl)
1992
1993
1994
1995
Casey
139.9
89.6
131.1
121.1
Davis
324.1
151.7
165.9
125.7
Mawson
122.2
133.9
144.8
141.6
Macquarie Island
37.8
51.2
45.8
29.7
Table 5: Total diesel usage in boilers 1992 - 95 (12)
Site
Yearly electrical energy production (MWh)
1992
1993
1994
1995
Casey
1,871.6
1,786.1
1,630.3
1,595.1
Davis
1,756.7
1,919.9
2,311.1
1,996.7
Mawson
2,255.1
2,162.9
2,283.6
2,368.3
Macquarie Island
584.4
521.1
541.8
593.6
Table 6: Total electrical energy production 1992 - 95 (12)

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3. SYSTEM IDENTIFICATION AND SIZING
Solar energy power outputs have been similarly estimated
for an installed photovoltaic capacity. Estimated hourly
In order to determine system sizing and performance, a
solar insolation levels for a plane, facing north and tilted at
computer model of station electrical load and energy outputs
an angle of 60o to the horizon (40o for Macquarie Island),
of wind turbines and photovoltaics was constructed. The
were divided by the standard 1 kW/m2 to order to calculate
model design follows that suggested by (14) using simple
the per unit kilowatt solar power capacity factor.
efficiencies to estimate the performance of wind turbines and
photovoltaics. A one-hour time step has been employed in
Using these time series for station load, wind and solar
the model at which the anticipated station energy demands at
power, three system configurations have been investigated:
the stations are compared to the available wind and solar
envisaged as possible implementation steps of renewable
energy resources. The effect of battery storage was included
energy generation systems at the stations.
by assuming a 90% energy conversion efficiency into and
1. Direct use of renewable power generation to supplement
out of storage (resulting in an overall efficiency of 81%).
station power with penetration restricted to 40% of
station load at each given time step, allowing adequate
Station electrical load levels were constructed using
frequency and voltage regulation by the diesel generator
monthly electrical power levels (reported from the stations),
sets. Any additional power produced above the 40% of
combined with temperature, wind, population , daily and
station load is dumped.
weekly cycles identified from observed recordings. Using
2. Inclusion of power regulation equipment, stabilising
the method described by Little (13), these were combined to
load over the one-hour time step, thus allowing for full
conduct one-hour time series representative of typical
load penetration of renewables for a given time step and
conditions observed at the stations.
intermittent diesel usage (any additional power
production above station load is dumped).
Hourly wind energy estimations (linearly interpolated from
3. Inclusion of storage in the form of batteries, with two-
3-hourly BoM observations), were used to estimate the
way inverters sized to take all excess power produced
available wind power over the hour at each of the stations.
from renewables above station load and provide full
The wind-power response curve reported for the Aérowatt
station load during periods of insufficient renewable
UM-70X in turbulent conditions (Figure 7) was used to
energy generation (if maximum energy storage has
determine the expected power for a given wind speed. This
reached, any addition power above station load is
value was then divided by the rated power of the unit (10
dumped).
kW) to define a per unit kilowatt capacity factor. For
scaling in the case of multiple units, this per unit kilowatt
Model runs were performed on the CRAY J90 computer
capacity factor has been assumed constant - allowing for
located at the Antarctic CRC (Co-operative Research
power estimations to be calculated against an installed wind-
Centre) in the University of Tasmania. All programs were
turbine capacity.
written using the MatLAB programming language and run
on a UNIX platform.
16
laminar flow
14
turbulent flow (0.85 reduction factor)
12
10
8
6
expected power [kW]
4
2
00
5
10
15
20
25
30
wind speed [m/s]
Figure 7: Power curve for UM−70X

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3.1
Renewable load penetration limited to 40%

capacity of 110 kW. The plant utilisation factor is three
times that for the other continental stations of Casey and
Results from the 40% penetration limited renewable power
Davis. Macquarie Island also has excellent conditions, with
use are presented in Figure 8 for each of the stations,
a 55 kW installed wind capacity expected to meet 30% of
indicating the ratio of total station energy met through the
the stations electrical energy needs.
presented installed wind and solar energy capacities. These
results have been calculated using a twenty by twenty grid
Mixed systems, comprising 100 kW wind and 100 kW
based on data recorded during 1995. Some of the best
solar, offer methods to increase the ratio of the total station
systems, allowing the greatest yearly energy production
energy needs (met by renewables), to 15% at both Casey
ratios for a given installed generation capacity, are presented
and Davis. The use of solar is hardly warranted at Mawson
in Table 7.
under a 40% renewable load limited system, and likewise for
Macquarie Island.
The amount of fuel savings has been calculated using the
average fuel efficiency as reported at the stations over the
A 40% renewable load limited system offers the most
period 1992-95 (15). The plant utilisation factor indicates
simple method to include a renewable power generation
the return expected from the given system, with high dump
component to the stations (requiring no extensive capital
loads and/or low renewable energy resources resulting in
investment other than that for wind turbines and
low values. Combined wind/solar options have lower
photovoltaics). For higher energy production ratios above
returns per unit kW installed, but meet a higher proportion
these, however, power regulation must be included in order
of the overall station energy demands.
to reduce the negative impact of high diesel cycling
resulting in lower fuel efficiencies and increased wear.
Returns for Mawson are excellent, with wind only systems
able to produce 25% of the stations needs for an installed
Casey [station energy ratio]
Davis [station energy ratio]
200
200
150
150
0.15
0.15
100
0.1
100
0.1
50
Installed wind kW
50
0.05
0.05
0
0
0
50
100
150
200
0
50
100
150
200
Mawson [station energy ratio]
Macquarie Island [station energy ratio]
200
75
60
150
0.3
45
100
0.25
0.2
0.3
30
0.2
0.25
50
Installed wind kW
0.15
15
0.05
0.1
0.05
0.1
0.15
0
0
0
50
100
150
200
0
15
30
45
60
75
Installed solar kW
Installed solar kW
Figure 8: Station energy ratio met by renewables (40% load limit)
Site
installed
installed
station
useable
fuel
plant
wind
solar
load met
energy
savings
utilisation
(kW)
(kW)
(MWh/y)
(ltrs/y)
factor
Casey
75
-
8%
128
37,776
0.19
100
100
15%
239
70,830
0.14
Davis
100
-
10%
200
56,708
0.23
100
100
15%
300
85,062
0.17
Mawson
110
-
25%
592
164,602
0.61
150
75
30%
710
197,523
0.36
Macquarie
55
-
30%
178
57,170
0.37
Table 7: Estimated performance of wind/solar systems limited to 40% of load

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