2. Executive summary
This report is a nancial feasibility and technical study for a wind farm on the
Isle of Cumbrae. In the following chapters the details of the project will be outlined
in a organized manner. The site was selected through a series of environmental
assessments further outlined in section 1. Arriving at a specic site the wind is
predicted and analyzed in section 2. The results of this analyzis resulted in the
choice of a best turbine for the specic site, the Vestas-90 2.0MW. Once a specic
turbine had been selected it was possible to carry out designs regarding the foun-
dation of the turbine and other construction considerations. These designs and
considerations can be seen in detail in section 5. During such a large project it is
always required to ensure that the quality of the materials is sucient to ensure
their functionality. The quality management is shown in detail in section 4 and
further in appendix C.
The nancial side of the project is shown in detail in section 6. This section goes
into the estimated energy production after the estimated losses from section 5.5.4
have been subtracted from the ideal energy production. The project is estimated
to produce about 8.98GWh of energy in its rst year and then slowly degrade by
0.15% per year. The turbine will be operating at a capacity factor of 51.25%.
The projected lifetime of this project is 20 years. This is based on data from the
manufacturer of the proposed turbine. During this time it is estimated that an
initial investment will gain 8.6% interest rate. This is a relatively high interest
rate making this a very protable long term investment scheme for investors. The
estimated payback period of an investment in this project is 3.7 years and it is
estimated to bring the initial investment, of 2.95 million $, to a total of 15.4million
$ by the end of its lifecycle.
3. Wind turbines are gaining ground as a viable source of energy. This is due to
the awareness of the impact of carbon dioxide on the earth's atmosphere and peo-
ple's attempts to mitigate the eect. The realization that fossil fuels are limited
resources is also a huge factor in the reason for changing to wind energy. Contribut-
ing to the production of sustainable energy, this project is very environmentally
friendly and will provide the Isle of Cumbrae with electricity for the near future.
This will be highly benecial to the island and contributes to the goal of the UK
of reaching 100% of its energy produced by renewable energy sources.
Included at the end of this document are planning permision cover letters to
apply for the necessary permits to build the required structures to carry this project
out. Also there is a Gantt chart that shows how the construction is proposed to be
carried out. In the appendix B there is a risk assessment that outlines the potential
risks to the project that Mass Power's engineers have thought of. These risks are
thoroughly thought out and include most if not all potential risks. In appendix
A, the computation done to implement all of the necessary calculations to analyze
the power output are presented.
4. Acknowledgements
From left, Back row; Callum Maxwell(Project manager), Li Xu(Construction manager), Joe
Thomas(Engineering manager), Tian Lou(Health and Safety manager), Scott Li(Environmental manager),
Front row; Hongrui Yan(Accounting manager), Deepthi Vijayan(Quality manager), Weiwei Shi(Business
manager), Atli Thrastarson(Research and Information manager)
The team would like to say Thank you to everybody in the group for all the commitment and hard work
that they showed throughout the project.
Also the team would like to thank course convener Dr. Marion Hersh for giving us the opportunity to
work on this project. Also the mentors Dr. Anthony Kelly from Electrical Engineering, Dr. Ian Watson
from mechanical engineering and Dr. William Stewart from Civil Engineering, their valuable assistance was
very important to the success of the project.
The nal and most important thanks are to our mentor, Ikpe Okara, for his continued encouragement
and motivation from the rst day, as well as his valued opinions on our work. It is with immense gratitude
we wish to acknowledge his eorts.
8. 1 Site
Having decided on the isle of Cumbrae for a wind farm, the rst objective was identify potential sites and
then to narrow down the selection to one specic site. The key factors for site selections are of course, wind
speed, environmental impact, noise impact, distance to grid and visual impact, in order of importance. In
order to select a site, specic values were given for each parameter and then the total sum gave the best site.
1.1 Environmental impact
Principles of government regulations [9] :
Conserve heritage assets appropriately to their signicance, so that they can be enjoyed by future genera-
tions. Encourage eective use of land, such as reusing previously developed land(browneld land), provided
that it is not of high environmental value. Focus signicant development in locations which are or can be
made sustainable. Support local strategies to improve health, social and cultural facilities and services to
meet local needs.
Potential factors
ˆ Habitats
The construction of a wind turbine can signicantly impact habitats especially in areas such as peat-
lands, and woodlands. The island is mainly farmland, therefore destroying habitatual areas is unlikely.
ˆ Animal species and plants
The areas that were identied, were not areas of natural animal habitat, aside from birds. Farm animals
can be easily controlled via fences so the main concern was the birds. Concerns regarding birds are,
collisions with the turbine, destruction of nests during construction. Most bird species on the island
are found at or close to the coast, there are several birds on the elds as well but none that cannot be
removed from site during construction without much interference to their lives, reference [39].
ˆ TV signal interference
TV signals are the most fragile electromagnetic signals(if interference is strong enough, it will result
in the most severe disruption to service) therefore if they are not aected neither should radio signals
or cellphones signals. Our site then must not aect TV signals, the best mitigation eect is to ensure
that there is no line of sight to the TV transmitter. Without line of sight there can only be little to
no interference, with line of sight however the interference can exist depending on the proximity to the
transmitter.
In the case of our sites there is no chance of line of sight because the tv transmitter on the island is
situated near the town and behind a hill respectively to the two sites closer to the town, gure 2.
1.2 Noise impact
There are two sources of noise from any wind turbine. The rst one is aerodynamic noise and the second is
mechanical noise. For our purposes we do not need to look into this at great detail because the manufacturers
of the turbines have already done this for us. It is therefore enough to look at the attenuation of sound
considering distance. The relationship that connects sound pressure to distance is described by equation (1).
Lp = Lw + 20log10(
rw
R
) (1)
Where Lw is the sampled sound pressure at distance rw from the source, R is the distance for estimated
sound pressure Lp. This relationship can be seen in gure 1 (computed with MatlabT M
see appendix A.
1
9. 0 200 400 600 800 1000 1200 1400 1600 1800 2000
−20
0
20
40
60
80
100
120
Distance R [m]
Soundpressure[dB] Noise from turbine
Figure 1: Noise levels
Figure 2: Noise map showing potential sites
A hard limit for noise should be about 40[dB] which is roughly about the average residence sound level,reference
[3]. In our case this means we need our turbine at the minimum 240 meters away from residential houses.
The turbine must therefore be positioned at least 240m away otherwise measures to reduce the sound eect
of the turbine, such as running it in noise reduction mode during nighttime, must be taken.
There were 4 potential sites selected ltered out from a noise map, gure 2, that shows the 240m radius
from every residential house on the island. This is eectively the easiest way to lter out sites on the island.
1.3 Visual impacts
From a visual environment there is little that can be done without reducing the eciency of the turbine.
The island is a pretty at environment, with small hills in between. The turbine will be raised to an 80m
hub height which means it will be visible on many parts of the island. The tactic chosen to deal with this is
to campaign for acceptance of the turbine through community forums and raising awareness of the benets
of sustainable energy.
1.4 Wind speed
The wind speed concerning the site selection was only the average wind speed attained from reference [21].
Sites 1, 2, 3 and 4 on the map in gure 2 have respectively average wind speeds of 6.7, 5.9, 5.7, 6.1[m/s].
For further wind analysis see section 2.
1.5 Distance to grid
Due to the small area of the island, distances to the grid connections are not perceived as a major issue,
however this was a factor to the site selection. For the sites proposed 1, 2, 3 and 4 the distances to possible
grid connections are respectively 400, 600, 300 and 400[m].
2
10. 1.6 Choice of site
Looking at gure 2 rstly site 1 is on a hill and does not stand on active farmland. It is situated in the
middle of the island so birds will mostly be Geese, Lawping, Crows and then other species that are less
numerous. Therefore the potential environmental impact is very minimal on this site. This site also has the
highest average wind speed and is reasonably close to the grid whilst maintaining distance to the town.
Site 2 is also on a hill, it is not active farmland, however it is situated on wetter land that is very close to a
marsh so there will be more birds such as Snipes that will be wandering around in addition to the ones that
will be found on site 1. This site has the third highest wind speed and is furthest from the grid.
Site 3 is situated in the middle of a large eld within a farm. This site will have similar bird species as site 1
but in addition it will also have forest birds, such as sparrohawks and treecreepers, and pool birds, such as
ducks and Mallards, furthermore there will have to be something done to keep the farm animals from harms
way. This site is the one that is closest to a grid connection, the connection will require digging up a huge
portion of farmland, however there is another connection available 600m away that does not go through as
much farmland. This site has the lowest wind speed of the 4 that were proposed.
Site 4 is situated in between 2 active elds which would require some additional work on the site beforehand,
it is also situated reasonably close to the sea so it is very likely that there will be some sea bird activity on
the site such as Gulls, Mallards and other less common sea birds. This site has the second highest wind and
is 400m away from the grid.
Site Wind eval Environmental eval Noise eval Grid eval Visual eval Total
1 10 8 4 2.5 1 24.5
2 8 7 3 1 1 20
3 7 5 6 4 1 23
4 9 6 5 2.5 1 23.5
Table 1: Showing the site evaluations numerically
Table 1 sums up the results of this chapter nicely. The total column shows us that the best site to commission
a wind turbine is site 1. This conclusion was reached by giving the sites numerical values for each aspect to
be considered. The most important aspect, wind speed, gets 10 for the best possible and then subsequently
reduces by 1. The second most important, environmental impact, gets 8 and then reduces by 1 subsequnently.
Third most important, noise, has highest value of 6 and then is reduced by 1 for each subsequential site.
The fourth most important, grid distance, gets a maximum of 4 and then 1 less for each subsequential. The
last is the visual impact and since very little can be done about it, and previously stated the tactic utilized
to x this is to raise public feelings towards the turbine, all sites get 1.
3
11. 2 Wind analysis
Accurate wind data for the island was dicult to obtain, the closest weather stations to it are in Dalry and
Prestwick airport. So in order to produce a wind probability density function for the island it was decided
that the data obtained from Prestwick airport, reference [38], would give sucient results to produce an
estimation of the wind for the island. The reason for Prestwick rather than Dalry is that Dalry is further
inland and therefore less similar to the characteristics of the isle of Cumbrae. In order to generalize the results
to nearby locations(namely the isle of Cumbrae) it is noted that the distribution is a Weibull distribution.
Weibull distribution is demonstrated in equation (2).
f(x, λ, k) =
k
λ
x
k
k−1
e−(x
λ )
k
(2)
Where k is the shape parameter of the probability density function and λ is the scalar parameter.
2.1 Probability density function
The data obtained from Prestwick was day by day average wind speeds. In order to appreciate it MatlabT M
was utilized to compute probability density functions and all further calculations. The MatlabT M
codes can
be seen in appendix A. In order to nd a best Weibull distribution(tted) to the data from Prestwick, an
online web applet was used(inserting our probability density from MatlabT M
), reference [23], to nd the
parameters k and λ. The tool provided the following results k = 1.80, λ = 5.08[m/s]. This was then plotted
against the actual data, gure 3.
0 5 10 15 20 25 30 35 40
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
0.2
wind [m/s]
probability
Prestwick at 21m
Data
Fitted Graph
Figure 3: Fitted graph vs. actual data
Now for further analysis of the wind the relationship
between the mean wind speed and the scalar and shape
parameters were examined. This relationship is de-
scribed by equation (3)
xmean = λ · Γ(1 + 1/k) (3)
This relationship is of great importance because it pro-
vides information for the determination of mean wind
speed provided the two parameters or otherwise deter-
mining one of the parameters given the other and the
mean.
The assumption here is that the shape parameter of
the Weibull will be relatively similar in areas that are
situated close to each other, the wind changes are re-
lated. This assumption is assumed to be accurate since
the wind speeds in connected areas are highly corre-
lated.
Given this assumption the shape parameter was then derived for the isle of Cumbrae as k = 1.80. Then
using this known k, it was possible to nd the value of the gamma function for Γ(1 + 1/k). The Gamma
function is dened as given by equation (4)
Γ(t) =
∞
0
xt
e−x dx
x
(4)
This is a very dicult integral to calculate exactly therefore an approximation based on Stirling's approx-
imation was used. The gamma function can then be rewritten as shown by equation (5) which is acquired
from reference [31]
Γ(t) = tt− 1
2 e−t
√
2π 1 +
1
12t
+
1
288t2
−
139
51840t3
−
571
2488320t4
+ O
1
t5
(5)
4
12. Here the O 1
t5 represents the big O notation, meaning the next parameter will be linear to 1
t5 . Equation
(5) is then rewritten as equation (6)
Γ(t) ≈ tt− 1
2 e−t
√
2π 1 +
1
12t
+
1
288t2
−
139
51840t3
−
571
2488320t4
(6)
This formula yields the result Γ(1 + 1/k) = Γ(1 + 1/1.8) ≈ 0.889226. With respect to equation (3) we are
only missing the information about the xmean in order to gure out λ. Since the average annual wind speeds
for three dierent heights at our site was already known, reference [21], it is simple to raise the height of the
wind speed using the formula for wind gradients, equation (7)
v(h) = vref ·
h
hhref
a
(7)
Here v(h) is the wind speed in [m/s] at height h in [m], vref is the reference velocity at height href given
by reference [21] and a is the Hellman's exponent. The height for the analysis was 80m, this allows the
visual impact of the turbine to be minimized, keeping it low while still maintaining wind resources good
enough for the big turbines. In order to calculate the wind speed at this height, the Hellman's exponent
is needed. From the wind source, there were already 3 dierent heights producing 3 dierent wind speeds.
Manipulating equation (7) we acquire equation (8)
a =
ln v(h)
vref
ln h
href
(8)
From equation (8) the average α was calculated by inputting data for the 3 available heights, the result was
a ≈ 0.11. Using this data v(80) was found to be v(80) ≈ 8.4[m/s]. λ was then determined from equation
(3) at a height of 80m giving λ80m ≈ 9.45[m/s]. MatlabT M
was then utilized (see appendix A) to provide a
probability density function, gure 4.
0 5 10 15 20 25 30 35 40
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
wind [m/s]
probability
Probability density function for h=80m at site
Figure 4: Probability density function for site at h=80m
5
13. 2.2 Wind direction
For wind turbines the wind direction has a direct correlation with the power produced. Imagine a turbine
with a xed angle, it can only produce at 100% capacity when the wind is facing it directly. The turbines
looked at in this report are however all tted with an active yaw control that makes the turbine face the
wind at all times. This of course can not be perfectly accurate and therefore it was required to add in an
error bar of some sort. The error caused by this is worst case scenario with the new yaw control systems a
5% deviation from perfect eciency (turbine facing the wind at all times).
Wind direction on the island is not logged in any public record. For that reason data was taken from Dalry
to give a rough idea of direction (Dalry is closer than Prestwick). The data for the direction was taken from
reference [35]. The results for the whole year can be seen in table 2 or in gure 5
N NNE NE ENE E ESE SE SSE S SSW SW WSW W WNW NW NWN
4.9 8.9 5.3 3.4 2.4 2.6 4.0 4.6 11.4 12.0 9.6 8.3 9.6 7.1 2.7 3.1
Table 2: Wind direction table showing probability of each in [%]
5
10
15
30
210
60
240
90
270
120
300
150
330
180 0
Wind direction probability in % in Dalry
Figure 5: Probability of wind coming from
each direction in Dalry
The vectors in gure 5 represent each direction in %
from center. It is worthy to note that the wind direc-
tion on the island should follow this trend of direction
except for the east and west directions, which should
even out. This is an educated guess based on the posi-
tion of the island compared to the bigger islands sur-
rounding it and normal wind behaviour.
Now as previously stated the turbines that were con-
sidered all have active yaw control. For example the
Vestas turbines, when purchased, come with a soft-
ware that automatically does this and allows for re-
mote monitoring of the turbine. The software also
has a feature which allows for manual overrides of the
automatic function, allowing for easy control of the
turbine.
2.3 Maximum winds
In order to be able to design a turbine foundation, a few maximum wind speed readings are required.
Since there have been no actual wind readings obtained at the site, a good approximation is needed. The
estimation made was that where the probability density function falls below a certain limit, to be exact
p(x) ≤ 10−6
= 0.0001%, where x is the wind speed, this is the limit that the maximum wind speed will occur
at. This approximation makes the assumption that every wind speed that is higher than x is so unlikely to
happen that it can be ignored, that is in reality it will never happen. Considering this at various heights,
that is h = 36m, h = 80m and h = 124m, to be more precise, an example was taken for the lowest, highest
and hub height of the Vestas-90 2.0 MW turbine. The calculations are the same as before using equation (3)
to nd λ for dierent heights. Since the shape factor, k, will be the same the gamma function will be treated
exactly the same as in equation (6). The average wind speed will be manipulated by equation (7) to t the
relevant heights. This gives the results λ36m ≈ 8.66[m/s] and λ124m ≈ 9.90[m/s] and λ80m has already been
calculated as λ80m ≈ 9.45[m/s]. Now these numbers are all that was required to construct a Weibull function
for each of these heights, this was done as before using MatlabT M
(see appendix A). From the denition of
the maximum winds it can then be derived from the MatlabT M
computation that the maximum and average
speeds for each height are as given by table 3.
6
14. Height [m] Maximum wind speed [m/s] Average wind speed [m/s]
36 37 7.7
80 40 8.4
124 42 8.8
Table 3: Maximum and average wind speeds for dierent heights
The data obtained can then be
used for foundation design. For
the actual probability of these
winds the notation ph(x) is used,
where h is the height, x is the
wind speed.
These maximum wind speeds shown in table 3 are the rst wind speeds, x, at relevant heights, h, that
resulted in the probability, ph(x), going below 10−6
. The chances of these winds happening is then, p36(37) =
7.813 · 10−7
= 0.000078%, p80(40) = 8.923 · 10−7
= 0.000089%, p124(42) = 8.077 · 10−7
= 0.000081%, for
heights h = 36m, h = 80m, h = 124m respectively.
This approximation suggest that these wind speeds will be the least likely and that any wind speed higher
than these are so unlikely that in reality they never happen. We can note here that lower, but close, wind
speeds are still very unlikely for example, p36(36) = 1.475·10−6
, p80(39) = 1.59·10−6
, p124(41) = 1.404·10−6
.
3 Turbine selection
Following the completion of wind
data, a comparison of the performance
of dierent turbines was carried out
for this exact circumstance. Each tur-
bine considered has a brochure avail-
able on the respective manufacturer's
website. These brochures include
functions for the turbines peformance
in dierent winds, power production
over wind speed. This function is rep-
resented on a graph in the brochures
and it has been hand interpreted by
our engineers into a vector form repre-
sented in MatlabT M
(see appendix A).
This function, W(x), was then used
with the previously acquired proba-
bility density function, p(x), as is put
forth in equation (9)
Pmean =
∞
0
p(x)W(x)dx (9)
Model Pmean[kW] Capacity Factor
GE 1.85-82.5 1.85MW 1,006 54.4 %
GE 1.6-82.5 1.6MW 933 58.3 %
GE 1.85-87 1.85MW 1,011 54.6 %
GE 2.5MW 1,303 52.1 %
GE 2.75-103 2.75MW 1,434 52.1 %
GE 2.85-103 2.85MW 1,474 51.7 %
Mingyang 1.5-77 1.5MW 803 53.5 %
Mingyang 1.5-82 1.5MW 852 56.8%
SCD 3.0-108 3.0MW 1,533 51.1%
SCD 3.0-100 3.0MW 1,462 48.7 %
SCD 3.0-92 3.0MW 1,345 44.8 %
Siemens 2.3-93 2.3MW 1,231 53.5 %
Suzlon 2.1-88 2.1MW 1,099 52.3 %
Suzlon 2.1-95 2.1MW 1,168 55.6 %
Suzlon 2.1-97 2.1MW 1,151 54.8 %
Suzlon 1.5-82 1.5MW 800 53.3 %
Suzlon 2.1-88 2.1MW 1,092 52.0 %
Vestas 2.0-110 2.0MW 1,117 55.9 %
Vestas 2.0-100 2.0MW 1,045 52.3 %
Vestas 2.0-90 2.0MW 1,103 55.2 %
Vestas 2.0-80 2.0MW 1,008 50.4 %
Table 4: Shows the capacity factors and mean production for
various turbines
And as before this calculation was carried out in MatlabT M
(for details see appendix A). A selection of models
from a few manufacturers and the results they provide can be seen in table 4. The capacity factor seen in
table 4 is purely based on the turbine and it does not take into account losses in transmission lines to the
grid or transformers in between the grid and the turbine.
This is also an average number over a whole year, for example, the Vestas-90 2.0 MW has Pmean = 1, 103[kW]
which in an ideal world suggest a steady production of 1,103[kW] over the whole year. However looking at
7
15. the wind data from section 2 an analysis was carried out on how many days a year this turbine would
be out of operation due to winds below or above the cut-in and cut-out wind speeds respectively. This
analysis was done in MatlabT M
(see appendix A) and resulted in the probability of the turbine being in
operation,poperation, is poperation = 0.8438 = 84.38%. Which means that over a whole year there will be 57
days that are unoperational due to wind. This number is the proposed start/stop cycles number, estimating
that the wind speeds will stay relatively similar over a whole day it is somewhat accurate to assume that
the actual number is equal or greater than 57.
3.1 Vestas-90 2.0MW
The Vestas-90 2.0 MW is the turbine that is proposed as the best turbine for this specic site. It produces
a high power output, 1,103[kW], while maintaining a high capacity factor as well. It does also ts in to the
IEC IIIA which is the wind classication of the site. The IEC IIIA standard for wind means, there is a
higher turbulence and the annual average wind speed at hub height is in the range 7.5 ≤ x 8.5. This is
not the only reason this turbine was selected as the best one for the site, it also has the best information
available and is widely implemented. Vestas is a company that has been around for over 30 years (founded
in 1979) and they have the incredible market share of almost 19% of global wind energy produced by their
turbines, reference [33]. For these reasons it was decided that this turbine was the best to install on the isle
of Cumbrae.
3.2 Monthly average power production
In order to provide a better view for the economic side of this project there was a need to investigate a
month by month description of the wind.
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month average
year average 1.12 0.92 0.85 1.18 1.07 0.80 0.62 0.92 0.87 0.97 0.95 1.73
Table 5: Monthly average divided by yearly average for each month
For a month by month analysis there is insucient data to
calculate a new shape factor for each month as the data
only spans one year. k = 1.80 was instead used to recreate
the shape factor for each individual month. The average for
each month was taken and as before equation (3) was used
to determine the parameters for the distribution of each.
Then using equation (9) an average power number was cal-
culated for each month. These numbers were then taken
and summarized before being compared to the yearly aver-
age in table 5, and then they were plotted in gure 6.
These numbers are too inaccurate for assessing power pro-
duced, however they are accurate enough to indicate when
maintanence jobs should be scheduled. It is anticipated that
over the summer the production is reduced, so if the turbine
requires some heavy maintainence it will be done over the
summer time as well as scheduled maintenance will likely
be during this time. It can also be noted that less power
will be produced over the summer than the winter, this is
in accordance with power consumption during those times.
1 2 3 4 5 6 7 8 9 10 11 12
500
600
700
800
900
1000
1100
1200
1300
1400
Month
Power[kW]
Power by month
Power number for each month for Vestas−90 2.0MW
Figure 6: Power number per month in kW
8
16. 4 Quality management
The purpose of a quality management system is to ensure the functionality of the project as a whole. Firstly
to ensure the construction is carried out in accordance with standards, secondly to ensure all materials meet
the standards required, thirdly to ensure that the site itself is made to meet the standards required. An-
other purpose of the quality management would be to ensure the reduction of carbon emission and accidents
during construction. Furthermore the quality management has to ensure that after the turbine is raised, its
operation meets the required standards.
Summarized the quality management has three aspects, management procedures, operational procedures
and general risk assessment.
To ensure all standards are upheld at all times the standard that will be followed by our company is the ISO
9001/IEC from the British Standard Institute(BSI). This standard summarizes many substandards that all
need to be met to meet this standard. Therefore, by adhering to this standard all other quality management
aspects are considered.
The IEC standards under this standard are made to develop international co-operation for the standardiza-
tion in electrical and electronics elds, since a wind turbine produces electricity these standards apply to it.
When the project gets into the construction phase there will be an external assessor that ensures that the
project meets all the specications necessary for the ISO 9001/IEC to gain certication. This certication is
required to be an acceptable contractor on the market. The certication is split in two parts, rstly type cer-
tication is performed for the wind turbine itself, this is done by the manufacturers of the turbine. Secondly
project certication is done to the complete wind farm. The dierent modules in a project certication are
described in a owchart shown in gure 7.
Figure 7: Modules of project certication
9
17. 4.1 Quality of construction
For construction, the operations that need to be overlooked by the quality management to meet standards
are as follows:
ˆ Location has to be made to meet standards, taking such action as moving nests if necessary build
fences to keep out animals and so on.
ˆ Road construction.
ˆ Foundation construction.
ˆ Health and safety standards during construction.
ˆ All bought parts need to be inspected and approved.
4.2 Management procedures of quality
To make it easier to implement the quality standards the following actions are needed:
ˆ The quality policies and procedures made understandable to everyone and made sure they are main-
tained by the project team.
ˆ Make sure quality procedures are continually updated throughout the project and improved if need be.
ˆ Make sure preventative and if necessary corrective measures are carried out to eliminate or minimize
risks.
ˆ Make sure the quality management plan documentation is led in a reasonable manner so anyone can
access it.
ˆ Quality audit needs to be carried out systematically, and make sure the quality plan is being followed.
ˆ To set measuring and testing procedures to ensure quality of everything and make sure calibrated
measuring equipment is being used.
4.3 Quality of operation
Operational procedures apply to everything after the construction phase. The quality management needs to
ensure the following things are up to standards:
ˆ Proper training for employees, such as training of Vestas operation software.
ˆ Ensure cleaning is done in a safe and secure manner.
ˆ If any repairs need to be made, make sure all components are up to standards and repair crew is
certied if necessary.
4.4 Risk assessment
In any big project like this there are risks that need to be considered. These risks have been througouhly
considered in appendix B.
For more details on the quality plan refer to appendix C.
10
18. 5 Construction
This section includes all aspects of the construction of a wind turbine on the site. It includes all the
foundation designs, transport of materials to the site, construction plan and more.
For the feasibility of this project it is vital to consider construction details. The selected turbine has the
production capabilities of 2 MW for the isle of great Cumbrae. There are six vital components that were
considered for the construction plan. These components are; wind turbine foundation design, planning
access roads, site planning, operating and maintanance building, trac management and delivering the
turbine components. A typical wind turbine construction process can be seen in gure 8.
Figure 8: Wind turbine construction process
The timetable for the project will be as seen in table 6.
Start date Finish date Job description
01.04.2014 30.04.2014 Cleaning around turbine site for access track and turbine information
01.05.2014 30.06.2014 Access track construction
01.07.2014 30.07.2014 Foundation construction
01.08.2014 30.08.2014 Turbine installation
01.09.2014 28.10.2014 Operation and maintenance building construction
01.11.2014 NA Wind turbine comissioning
Table 6: Showing the dates of the dierent phases of the construction
11
19. 5.1 Construction of access tracks and trac management
Transportation of the components to the site requires the construction of some additional roads as well
as reinforcing some that already exist. The basic design principles for the roads are as shown in table
7. The objectives of these roads will be to maintain water ow across the line of the road and minimize
disruption to the hydrology of the soil. Access requirements for construction and wind turbine delivery
vehicles must be met. Where new roads are required, they will follow already existing tracks, if possible, to
reduce environmental impact. Roads shall t into the landscape avoiding unstable ground, constructed to a
uniform longitudinal and horizontal prole. The crossing of watercourses and eects on local hydrology will
be minimized as well as identied environment and archaeological constraints will be avoided.
Design speed 25m/h
Design load Max component weight
Road width 5m running surface (slightly wider on bends)
Max gradient straighs 7.1◦
(12.5%, 1/8)
Gradients on bends Inner radius 60m-max gradient 8%
Outer radius 90m-max gradient 10%
Cross slopes Cross slope of land traversed by road no steeper than 18◦
(33%, 1/3)
Table 7: Showing the design principles of the access roads
The total stretch to the town of the access road is shown in gure 9.
Figure 9: Access road to town(image, edited from Google maps)
12
20. To get a better appreciation of how the roads need to be altered, gure 10 includes the length of each stretch
of road inside the town. Figure 11 includes an illustration of the problems with the nal turn onto College
street, the box on the down left in gure 10.
Figure 10: Access road inside town(edited from
google maps)
Figure 11: Turn at College street(photo taken
and edited by Li Xu)
Figure 10 contains 3 boxes, all of which are a bit of road that needs to be reinforced, the box on the right
is over a turn that needs to be made wider, the box on the left is the turn onto College street, the box on
top is where the new road will need to be connected to the old one. College street is a stretch of road that
is only 3.5m wide, this is enough to transport so long as opposite trac is closed down during the transport
period. This can be achieved by planning the transport during night time with a police escort.
5.2 Site plan
The layout for the construction compound is shown in gure 12. This temprorary construction compound
will be approximately 50 · 70[m2
] and then additionally a temprorary car parking area 30 · 30[m2
] will be
constructed. Not all of this area needs to be purchased, however it will be necessary come to an agreement
with the farmer that owns this area and rent it from him during the construction period. The 50 · 70[m2
]
area will however need to be purchased indenately for the turbine. These areas will include:
ˆ A bundled area for storage of fuels and oils
ˆ A receiving area for incoming vehicles
ˆ Containerized storage areas for tools, small plant machinery and parts
ˆ Toilet facilities with a packaged treatment system to be designed in liaison with SEPA
13
21. Figure 12: Construction compound layout
It should be noted that the compound layout in gure 12 does not include the location of re extinguishers,
rst aid kits and a debrillator. These things will be placed on the site where the health and safety manager
sees t as soon as work starts on the site.
5.3 Foundation design
The foundation plays a key role in the stability and lifetime of the turbine. With this particular project the
most appropriate foundation type is the spread footing foundation. It is cheap and more importantly strong.
For the designing of the foundation, a few parameters were identied:
ˆ Bearing capacity
ˆ Stability analysis
ˆ Structure design
ˆ Shear force design
ˆ Failure analysis
ˆ Overturning moment(M)
ˆ Total turbine weight (V)
ˆ Horizontal shear force (H)
14
22. The rst step in identifying these parameters was analysing the soil at the site. This analysis was based on
reference [15], which indicates the wind farm location mainly consists of old sandstone. Then in order to
calculate the bearing capacity of the soil, rstly the strength parameters of the soil had to be calculated.
Equation (10) shows these calculations.
qult = c · Nc + γD · Nq +
1
2
B · γ · Nγ (10)
Where γD is the overburden pressure, B is the width of the foundation, γ is the unit weight of the soil, Nc
is the bearing capacity factor (cohesion), c is the cohesive strength of the soil, Nq is the bearing capacity
factor(surcharge and friction), Nγ is the bearing capacity factor (self weight and friction).
The foundation must fulll the condition
H
qult
0.4 (11)
The stability of the structure can be analyzed using equation (12).
e =
M
V
B
2
(12)
Where M is the bending moment at the bottom of the structure, V is the vertical load on the structure
including the weight of the structure, B is the width of the structure(in our case diameter). The e is the
eccintricity of the foundation. This number must be less than the radius of the foundation, B
2 , in order for
the structure to be stable.
The foundation's structural design is made according to european standards for concrete strength and safety
parameters. The european safety factors can be seen in table
Limit state Concrete, λc Reinforcement, λs Long time eect λαcc Fatigue, λfat
ULS 1.50 1.15 1.00 1.00
SLS 1.00 1.00 1.00 1.00
Table 8: Table showing values for safety factors concerning structural designs
The wind shear force is calculated as shown in equation (13)
Fd = Cd · P · A · v2
(13)
Where P is the air density, A is the surface of the wind turbine, v is the wind velocity and Cd is the drag
coecient.
The turbine that was selected, the Vestas-90 2.0MW, has a hub height of 80m. The rotor blades are 44m long
and have an average width of 1.07m. With these dimenstions the moment and shear force were calculated
as in equations (14) and (13).
Mu = Fd ·
B
2
(14)
Where Mu is the moment force caused by the wind on the structure. Then the critical shear force is calculated
as shown in equation (15).
Fdc =
Pu
4
+
Mu
2r
·
B2
− πr2
B2
(15)
Where Pu is the force of the mast and rotor blades, r is the distance from the center of the mast to the
critical shear line. Equation (16) is then used to calculate the distance of reinforcement bar required to
endure the bending moment on the foundation.
L =
2B − (C + Cp)
4
(16)
15
23. Where L is the cantilever distance, C is the width of the steel column, Cp is the width at the bottom of the
column. The factored bending moment, Muc, is calculated by equation 17.
Muc =
Pu · L2
2 · B
+
2 · Mu · L
B
(17)
To nd the area that needs to be reinforced by steel, equation was used.
As =
fck · B
1.176 · fy
·
d − (2.353 · Muc)
(Ø · fc · B)0.5
(18)
Where fc is the compressive strength of concrete, B is the diameter of the foundation, Ø is the exure in
reinforced concrete, fy is the yield stress of reinforcement steel bars and d is the diameter of the reinforcement
steel bars. The sectional moment ad sectional shear forces were calculated at four dierent points equally
spaced on the beam. In addition, the sectional forces were calculated for all sets of loading, and fatigue
loading where need be, (one maximum and one minimum).
To approximate the cost of the foundation a report made by Elforsk, reference [5], was used as a source for
the estimation. This report suggests that the foundation will use approximately 450m3
of concrete and 40
tons of steel reinforcing. The foundation design can be seen in gure 13 and then further explained by table
9.
Figure 13: Showing the foundation design, taken from reference [5]
Material type Length/Thikness
Soil Old sandstone
Concrete layer Grade C25 concrete 100mm
L1 Grade C37 concrete 10m
L2 Grade C37 concrete 1.6m
L3 Grade C37 concrete 1.8m
Pedastal Grade C37 concrete
L4 Grade C37 concrete 0.6m
L5 Grade C37 concrete 5.5m
Top layer reinforcements Ø25 mm B500B
Bottom layer reinforcements Ø25 mm B500B
Shear reinforcements Ø25 mm B500B
L6 Ø25 mm B500B 4.8m
Table 9: Showing the parameters of gure 13
16
24. 5.3.1 Fatigue analysis
In order to make some analysis of the structure the point of failure for the turbine was investigated. The
wind turbine foundation designed in accordance with ULS, SLS and European standards. The foundation
concrete class is C37 and the compression strength fck of that concrete class is 30MPa. In order for the
structure not to collapse equation (19) has to be fullled.
fcd,fat = fcd 1 −
fck
250
30[MPa] (19)
Where fcd is the concrete tension strength and fck is the concrete compression strength. A margin of safety
or MOS can be calculated by equation (20).
MOS =
Failure load
Design load
− 1 (20)
The MOS of this project is calculated as 0.70, which means that the load needs to be 70% more than the
maximum load in order for the structure to fail. This is a safe margin because the approximation of maximum
wind speed acquired in section 2.3 shows that this is an extremely unlikely event.
5.4 Turbine delivery and rented equipment
There are a few key components that need to be delivered by big trucks, these are: tower, support crane
and main crane, generator, nacelle, hub, blades, transformer and building materials.
For transportation
purposes table 10
sums up the dimen-
sions of the dierent
components.
Block Length [m] Max width [m] Max height [m] Max weight [ton]
Blade 3x 44 3.5 4.0 6.7
Hub 4.2 4.0 3.3 18
Nacelle 10.4 3.4 4.0 70
Tower 2x 40 4.0 4.0 80
Generator 7.7 3.0 3.5 14
Transformer 2 1.2 2.4 4
Table 10: Vestas-90 2.0MW component dimensions
For the construction,
rented equipment will
be required as shown
in table 11. The
table includes esti-
mated costs for rental
of the equipment per
day as well as the
total amount, prices
from references [2],
[27], [26], [7], [12],
[32], [28], [40].
Type Nr. Duration[days] Daily rental rate ($) Total rental cost ($)
Crane (small) 1 30 577 17,310
Crane (400 ton) 1 10 8,536 85,360
Dump truck 2 40 209 16,720
Blackhoe Loader 2 20 400 16,000
Water truck 1 30 350 10,500
Excavator 2 60 220 26,400
Bulldozer 1 22 350 7,700
Roller 2 30 250 15,000
Flatbed 1 10 225 2,250
Total NA NA NA 197,240
Table 11: Required rented equipment for construction
17
25. 5.5 Grid connection
The grid connection is one of the key features of this project. It is what allows the company to sell its
produced energy to a larger network, allowing the minimization of nancial risk. The network can be seen
in gure 14.
Figure 14: Electrical network connecting to the grid
Figure 14 shows the structure of the
network. The bottom of the network
shows the power source(the wind tur-
bine) which is then connected to a
transformer and then through various
protective mechanisms into the grid
itself. It can also be seen that at
the dotted line is where the generated
power is delivered, that is everything
above the dotted line is the infras-
tructure of the DNO network and not
Mass Power's.
The Mass Power infrastructure con-
sists of the source, the step up trans-
former, a circuit breaker in case of
emergencies and then a protection for
our infrastructure. These components
will all have to be approved by the
SSE before they are installed since
they are the ones that will resell the
energy produced by Mass Power.
The transformer will be a step up
transformer that takes the electricity
produced by the turbine, 690[V], and
steps it up to 33,000[V]. The circuit
breaker is there in case of emergencies,
it might be required to isolate the tur-
bine and transformer completely from
the grid to protect them or possi-
bly even protect the grid. The pro-
tection system is there to make sure
that the voltages and frequencies be-
ing produced are correct also to min-
imize earth faults and loss of main,
the relays are then there to control the
ow of electricity.
5.5.1 Earthing
It is very important that earthing is done properly in such a project, there are three main types of earthing
that are possible:
ˆ Solidly earthed - The neutral point is solidly bonded to the earth, this can result in high fault currents
ˆ Resistance earthed - The neutral point is bonded to the earth through a resistance in order to reduce
earth fault currents
18
26. ˆ Arc suppression coil earthed - The neutral point is connected to the earth by inductive coils that are
tuned to match the network capacitance and hence limit the earth fault currents
These three options are all viable, Mass Power can not choose one however, but the choice of these remains
in the hands of the SSE, who will have the nal say in this. They are listed above from unsafest to safest
and from cheapest to most expensive.
The relays are powered by batteries. The distribution network operator may be prepared to provide a fuse
supply from their battery and charger. This is on the condition that this supply is not extendible outside
our boundary, the amount of drain imposed by the generator on the batteries is xed and that it is mutually
agreed that an alarm will be tted to the battery charger connected to the DNO's telecontrol system. In
such a situation Mass Power is liable to pay any costs associated with the failure of the battery charger due
to the failure of the generator system.
The alternative is that Mass Power provides its own battery system which would be topped up by a charger
connected to an AC supply. For only one turbine this is a costly procedure therefore the former option is
more suitable.
5.5.2 Cable trenching
Figure 15: Map showing the already existing grid, reference
[25]
The cable connecting the turbine to the
grid will be buried rather than installed as
an overhead line. The reason for this is the
proximity of the turbine to the grid, that
is the distance is small, and the fact that
overhead lines have a huge visual impact
on the site which should be avoided when
possible. The distance that needs to be
covered by Mass Power is approximataley
400[m], the technical specs of the cable
will be as shown in table 12 . The cost of
trenching such a cable is 165$ per meter,
reference [34].
Rated voltage 33[kV]
Max operating voltage 36[kV]
Max conductor temperature 90◦
C
Max operating temperature 130◦
C
Short circuit temperature 250◦
C
Max bending radius 12x diameter
Table 12: Showing technical specs of cable
19
27. 5.5.3 Connection process
Figure 16: Showing
the dierent connec-
tion phases
Figure 16 shows the dierent phases that are associated with connecting
the turbine with the grid. The rst one is the planning phase, this phase
includes all that has been done so far as well as contacting the SSE and
getting even more detailed specications of the grid in the vicinity of the
turbine. These detailed specications will include everything about the grid
itself on the island as well as readily available spare capacity on the network.
This phase includes a price estimation of the connection.
The second phase is the information phase, during this phase the SSE will
be asked to prepare a draft connection design that supplies Mass Power's
engineers with an outline of the generation scheme.
The third phase is the design phase, during this phase our engineers will
review the draft supplied by the SSE and decide which of their options the
project will utilize. The extent of information required will be specied by
the SSE at the end of the information phase. The SSE is required by law to
supply Mass Power within three months with a receipt of all required infor-
mation. During this phase Mass Power will be supplied with a connection
oer from the SSE. The details of this oer need to be examined carefully
and mutually agreed upon with the SSE.
The 4th one is the construction phase, this begins once all terms of service
have been agreed upon by the SSE. A liaison between Mass Power and SSE
will be in place to ensure that the connection is up to the required qual-
ity. During this phase the construction of the wind turbine needs to be
nished. It needs to be ensured that all appropriate lease agreements have
been signed to enable the electrical cables to be placed in the ground. A
meter opperator needs to be appointed to undertake the task of providing
metering equipment and to make arrangements for meter readings and data
collection by the appropriate parties. The nalisation of the agreement with
the SSE regarding the purchase of power will be done during this phase. In
this phase the following agreements need to be made:
ˆ A connection agreement - Regarding the conditions based on which a
connection has been oered
ˆ A use of system agreement - Regarding the terms based on which Mass
Power is allowed to use the SSE network
ˆ An adoption agreement - regarding the terms on which SSE will adopt
the infrastructure set up by a third party contractor
ˆ An agreement covering the arrangements for the operation of the in-
terface between the SSE network and the Mass Power infrastructure.
This region needs to be accessible by both the SSE and Mass Power
The last phase will be the testing and commisioning phase, during which Mass Power will hand the SSE a
detailed technical information about the wind farm. This phase will also incorporate testing of all equipment
that has been installed by the SSE, Mass Power or a third party associate. It will be during this phase that
the date, in which power generation and export will commence, will be announced to the SSE.
20
28. 5.5.4 Losses
In order to complete the business feasibility the losses in the system had to be assessed. The previous
calculations carried out assumed no losses in transmission or wind direction (see section 2.2). The losses
used in the business feasibility calculations are for the worst case scenario losses. The rst loss in the system
is due to the wind direction. This accounts for circa 5% of the power being produced, this was calculated
from the average power over the year. Next in the system is the transformer and according to reference [22],
the losses in a transformer such as the one Mass Power will use is 1-2%. As stated earlier the worst case
scenario was assumed which gives 2% losses. The last signicant loss is the transmission line which goes the
rest of the way until the SSE infrastructure takes over. Losses in cables are calculated as shown in equation
(21).
Losses = I2
R (21)
where I is the current and R is the resistance of the cable. For this estimation a typical cable will be used,
reference [19], a 33kV single core aluminium cable is the worst case scenario. Using this cable at the turbines
maximum capacity, 2MW, gives a current of circa 60[A], calculated from equation (22).
P = V I (22)
Then using the aluminium cable, a 50mm cable was used for estimation (in reality a bigger cable made out
of copper will most likely be used but this is a decision that needs to be taken in co-operation with the SSE).
The cable has a resistance of 0.821Ω/km, for the worst case assumption, the distance is approximated as
500m and then the loss at the turbine maximum capacity is found to be 1.5kW.
In summary the lossesin the system are 5% from the wind direction, 2% from the transformer and then worst
case assumes a constant of 1.5kW lost in the line. This results in the total power number being calculated
in [kW] as given by equation (23).
PActual = Pmean · 0.95 · 0.98 − 1.5 (23)
This yields the result PActual = 1025[kW].
5.6 Constructional health and safety
Numerous factors need to be considered during the construction phase in regards to the health and safety
of the workers. It must be ensured that heavy equipment is used properly, especially the crane during the
erection. The crane must be placed on solid ground that has no potential to shift, before use all crane
equipment must be examined and made sure it is correctly placed. It is paramount that workers receive
proper training in all operations they take part in. Workers working in high places must be taught to use
personal fall arrest systems to ensure no serious injuries will occur. These are the main issues that need to
be acted upon during the construction, for a further list refer to appendix B.
5.7 Construction summary
The proposed design requires a compound of roughly 3500m2
accommodating the operation and maintenance
building. It includes space for the network control building and also the outdoor electrical infrastructure.
The diameter of the foundation is 10m, the control building will measure 10·20m2
.
6 Business
6.1 Isle of Cumbrae power consumption
The estimated power consumed by the isle of Cumbrae was calculated using the average power consumption
per capita in the UK, reference [1]. This average power was seen as Pavg = 5516[kWh] for 2011. Then in
21
29. order to make use of this the number of inhabitants on the island was acquired from reference [24] as 1,376.
Equation (24) was then used to calculate the energy consumed by the island.
Consumed Energy = Pavg · Population (24)
These calculations suggest that the island requires 7.59[GWh] annually. This number can be represented as
average power consumed at every moment by equation
Power =
Consumed Energy
Hours
=
7.59 · 109
365 · 24
= 866[kW] (25)
6.2 Turbine Degradation
To complete a thorough business plan the degradation of the turbine had to be investigated. The turbine
will degrade somewhat over its life span of 20 years. Degradation of wind farms happens over a long period,
however it is dicult to measure since wind changes from year to year, therefore these calculations are
based on a Danish study, reference [36]. This study was done on an oshore wind farm which will suer
more from degradation than an onshore wind farm since the components are exposed more violently to the
elements. The study was done for 3 wind farms, 2 of which increased in capacity factors, one of them showed
a decrease in capacity factor of 1.5 percentage points over 20 years. This is the number used for calculations
here so the actual capacity factor has to be calculated. Looking at section 5.5.4 then the actual mean power
is PActual = 1025[kW]. As the turbine can at its maximum capacity produce 2MW then this provides a
capacity factor of 51.3%. Degrading 1.5% points over 20 years means that after 20 years the capacity factor
will be 49.8% and assuming linear degradation the yearly degradation was found using equation (26).
PActual · x20
= PActual,20 ⇒ 20 PActual,20
PActual
= x ≈ 0.9985 (26)
This shows that every year the turbine degrades 0.15%.
6.3 Annual power production
To estimate the energy production per year the power number acquired in section 5.5.4, PActual = 1025[kW],
is multiplied by hours in a year, detracting only maintenance hours, as shown in equation (27).
Energy Per Year[kWh] = PActual · (Hours In A Year − Maintenance Hours) (27)
It is worth noting that the PActual already includes all downtime caused by the wind. According to the
project's health and safety manager the scheduled maintenance tasks for the turbine will take roughly 40
hours per year. Using these numbers the power produced by our turbine becomes Eproduced = 8, 979, 000[kWh] ≈
8.98[GWh].
6.4 Taris
The primary source of income over the project's lifecycle will be the sale of electricity. This revenue stream is
dependant on the feed-in tari, paid to the Mass Power from the company in control of the grid connections,
the Scottish and Southern Electric(SSE). According to data from reference [16], energy generated from a
power plant of between 1.5MW and 5MW in capacity the tari for generation is 3.32p/kWh. On top of
this there is an export tari to the grid which is 4.64p/kWh. In the case of Mass Power the wind farm
sells all of the energy and therefore the tari used is 7.96p/kWh. The whole business plan has been done in
dollars so the conversion rate was taken on the 18.03.14 and it was ¿0.6 per dollar leading to a total tari
of 13.21cents/kWh.
22
30. 6.5 Estimated cost
The estimated cost of the project can be split into inital cost(ICC) and annual operation expenses(AOE).
These then can be split down further into base components. The biggest cost of the project will be the wind
turbine itself.
6.5.1 Wind turbine cost
The exact price of the turbine cannot be found online anywhere and it will not be exact until the actual
purchase of the turbine. To get a good estimate we looked at a project done by IRBS international, reference
[14]. According to this project the complete Vestas-90 2.0MW turbine will cost roughly 3,369,663e this price
was converted into dollars on the 21.03.14 as 0.72e per dollar. Giving us the ballpark price of 4,652,829.67$.
This price is considerably higher than the one estimated by Mass Power for the reason that this project uses
a higher turbine and the turbine model is the same but it is meant for a dierent wind class(a higher one).
The total cost of the project can be seen in table 13.
Component Cost[$]
Wind turbine 1,700,000
Connection 150,000
Access road 35,000
Permits 60,000
Foundation 250,000
Decomissioning 25,000
Rented equipment 200,000
Engineering cost 86,000
Transportation cost 90,000
Labour cost 260,000
Site buildings 100,000
Total 2,956,000
Table 13: Showing the captial
expenses of the project
Some of these costs can be divided further. The wind turbine includes
only the turbine itself as it comes from Vestas, the connection includes
wiring from the turbine to the transformer from there through all of
the protective mechanisms to the grid. The connection also includes
a fraction of the transformers expenses which are mostly represented
as annual expenses, paying o for the transformer and its maintenance
yearly over its life cycle. The operational expenses(OPEX) can be seen
in table 15. The access roads includes the xing of all roads already
existing as well as making the new stretch to the turbine. The permits
include all consultants expenses for acquiring the permits, it includes
costs in regards to building permits and costs for being certied for
the required standards. The foundation includes the material that
goes into the foundation as well as the soil boring and preparations
that need to be done on site before the construction starts.
The decomissioning is a part of the capital expenses be-
cause starting such a project means that it also has to be
nished at some point and reserving money from the capital
expenses to do this is good practice. The rented equipment
is the rental of all big machinery that is required to execute
the construction of this project(can be seen broken down in
table 11. The engineering cost includes all design costs, and
paying the managers for their work this can be seen broken
down in table 14, the expected time for each manager is 500
hours. The transportation cost includes the cost associated
with getting materials to the island. The labour cost is the
estimated wages required for all the construction. The site
buildings include the material for the other structures on
the site.
Position Salary[$]
Project manager 12,000
Project accountant 11,000
Engineering manager 17,000
Health and safety manager 10,000
Quality manager 11,000
Environmental manager 12,000
Construction manager 13,000
Total 86,000
Table 14: Showing the estimated expert
salaries for their work
As can be seen in table 15 the transformer is to be paid of slowly over the lifetime of 20 years. This does
include, and mostly consists of, the maintenance that has to be performed on it for its lifecycle.
23
31. 6.5.2 Operational costs
The operational costs are summed up in table 15. The maintenance of the turbine will be done using proper
These as stated before consist of maintenance of the turbine and site, as
well as maintenance of the transformer which in table 15 is referred to
as the transformer and not maintenance. There are various health and
safety features that need to be considered during the operation as well,
this all falls under the maintenance and includes making sure there are
warning signs up if possible ice throw. Making sure the turbine is
stopped in case of excessive wind. Making sure all feautures such as
the aircraft protection on the blades is functional. Verifying that the
gates on the access roads are locked and no accessible by public. Bird
repellers must also be placed and ensured to be operational.
Operation Annual Cost[$]
Land lease 12,000
Maintenance 50,000
Warranty 20,000
Insurance 15,000
Transformer 24,000
Total 121,000
Table 15: Showing the opera-
tional expenses of the project
equipment as per the quality plan, section 4. This includes things as climb assists for workers, if working in
very conned spaces, such as inside transformer, oxygen bags are needed. When doing bung and resurfacing
of blades respirators are necessary. The proposed maintenance hours for the project yearly are 40 hours,
reference [13], on top of which is a budget to have monitoring of the turbine at all times.
6.6 Financial feasibility
The nancial feasibility of this project is the biggest contributor to the decision if it should be carried out.
Table 16 sums up all the required components for such an analysis.
Year AEP[kWh] LRC[$] OPEX[$] AEX[$] Electricity income[$] Income[$] Accumulated cash[$]
0 0 0 0 0 0 -2,956,000 -2,956,000
1 8,979,000 270,293 121,000 391,293 1,186,125 794,832 -2,161,167
2 8,965,532 270,293 121,000 391,293 1,184,346 793,053 -1,368,113
3 8,952,083 270,293 116,000 386,293 1,182,570 796,277 -571,836
4 8,938,655 270,293 116,000 386,293 1,180,796 794,503 222,667
5 8,925,247 270,293 116,000 386,293 1,179,025 792,732 1,015,399
6 8,911,869 270,293 116,000 386,293 1,177,256 790,963 1,806,362
7 8,898,491 270,293 116,000 386,293 1,175,490 789,197 2,595,560
8 8,885,143 270,293 116,000 386,293 1,173,727 787,434 3,382,995
9 8,871,815 270,293 116,000 386,293 1,171,966 785,673 4,168,668
10 8,858,508 270,293 116,000 386,293 1,170,208 783,915 4,952,584
11 8,845,220 0 116,000 116,000 1,168,453 1,052,453 6,005,038
12 8,831,952 0 116,000 116,000 1,166,700 1,050,700 7,055,739
13 8,818,704 0 116,000 116,000 1,164,950 1,048,950 8,104,690
14 8,805,476 0 116,000 116,000 1,163,203 1,047,203 9,151,893
15 8,792,268 0 116,000 116,000 1,161,458 1,045,458 10,197,352
16 8,779,080 0 116,000 116,000 1,159,716 1,043,716 11,241,069
17 8,765,911 0 116,000 116,000 1,157,976 1,041,976 12,283,045
18 8,752,762 0 116,000 116,000 1,156,239 1,040,239 13,323,285
19 8,739,633 0 116,000 116,000 1,154,505 1,038,505 14,361,791
20 8,726,523 0 116,000 116,000 1,152,773 1,036,773 15,398,565
Table 16: Showing the annual electricity produced(AEP), the loan repayment cost(LRC), the operational
expenses(OPEX), the annual expenses(AEX), the electricity income, the income after expenses, the cash
ow beginning at the negative amount of the captial expenses(CAPEX)
24
32. To analyze if this project is then nancially viable rstly we take a look at the payback period. The far
right column in table 16 shows the accumulated cash ow beginning at the end of year 0 with a negative
value of the capital expenses. It is clearly seen that at the end of year 4 the accumulated cash has become a
positive number meaning that at that point the project has generated more cash than went into it to begin
with, in other words the payback period is roughly 4 years. Now there is a column designated specically
for loan repayment that continues annually until the end of year 10. The income column is calculated by
subtracting the AEX from the Electricity income. From the tbale it is clear that after 4 years there should
be enough money on hand to pay the initial expenses if it would come to that, this money will be kept in
a backup fund as is briey mentioned in appendix C. Equation (28) demonstrates how the exact payback
period is calculated as 3.7 years.
n
p + n
+ Nn (28)
Where n is the absolute value of the last negative value in the accumulated cash ow, p is the value of the
rst positive value and Nn is the years that have passed when the last negative value n is the accumulated
cash ow. The capital expenses shown in table 13 can also be seen graphically in gure 17. Figure 18 shows
the accumulated cash ow column from table 16 graphically. It should be noted that the loan acquired in
table 16 is a typical 1.9million $ loan as from a bank.
Figure 17: Pie chart showing the capital expenses Figure 18: Accumulated cash ow of the project
The bill of quantity can be seen in table 17, prices acquired from contact with various construction companies
and reference [37].
Item Quantity Cost per unit [$] Total cost [$]
New road ≈200m 90 per meter 18,000
Concrete for foundation ≈450m3
125-165 per m3
56,250-74,250
Rebar - 25mm ≈40tons 550 per ton 22,000
Aluminium ≈200m2
65-125 13,000-25,000
Table 17: Bill of quantity
6.7 Carbon oset
The carbon oset calculations are all based on reference, [29]. These references suggest that the annual
carbon emission saving should be calculated as shown in equation (29).
S[tCO2/year] = Eout · Efuel (29)
25
33. Where Eout is the energy produced by the wind farm and Efuel is the emission factor for the fuel that would
produce the energy if it was not produced by wind. Energy produced into the grid in UK is composed of
electricity generated by gas(46%), coal-red(31%), nuclear(14%) and renewable(5.5%), reference [11]. The
Efuel parameter was acquired from reference [29] as Efuel = 0.43[tCO2/MWh](tons of CO2 per megawatt
hour). There is also a carbon cost to transport the turbine to the location, operate it and decomission it.
This loss of carbon is calculated as in equation (30).
L[tCO2] = 934.35 · Cturb − 467.55 (30)
Where Cturb is the capacity of the turbine. This L accounts for all CO2 emisssions during the inital set up
of the turbine, the operational and maintenance of the turbine and the decomissioning of the turbine. This
is an absolute value calculated for the total lifetime of the turbine. Using equations (29) and (30) we have
calculated the carbon oset of our turbine as S = 4136[tCO2/year] and the carbon loss as L = 1419[tCO2].
6.8 Summary
Looking at these numbers presented in the business section it can be seen that the project is protable. In
the production of electricity everything has been considered including the degredation of the turbine over
its lifecycle and the losses in transmission lines. This means that the accumulated cash ow after 20 years
is the estimated total income of the project, seen as 15,398,565$ in table 16. This means that in only 20
years the initial investment increased more than vefold. Equation (31) shows how interest is calculated and
can be used to nd out the equivilent gain per year.
I · x20
= G · I (31)
Where I is the initial money, x is 1 plus the interest and G is the gain. This yields the result that this project
will average 8.6% interest for its investors. Therefore the project is both very protable and furthermore it
will produce sustainable energy for the isle of Cumbrae for the next 20 years.
26
35. 8 Planning permission cover letter
Mass Power PLC
James Watt Building
University of Glasgow
Glasgow
G12 8QQ
Dear North Ayrshire Council,
Outline planning application: land in the center of the Isle of Cumbrae adjacent to College
Street
It is with great pleasure that we are able to submit an application on behalf of the company Mass Power
PLC.
As you may be aware, this application for planning permission follows the completion of a successful feasibility
study of the potential implementation of a wind turbine to generate electricity for the inhabitants of the
Island.
Our purpose is to help the Scottish Government achieve its 2020 target of 100of electrical generation to come
from renewable sources. This application for planning permission follows consultation with the locals of the
island, and is supported throughout the community.
The environmental impacts of the proposed wind turbine are seen to be low, and can be viewed in the
Environmental Impact Assessment of the attached report. The construction phase of the project may have
a minor impact on the locals initially as selected roads must be reinforced to allow delivery of the key
components of the Turbine. During the construction phase there is a risk of noise pollution and air pollution
via delivery of the project components, however when the turbine is commissioned the likely disturbances will
be minimal, with little trac to or from the site. Drainage plans have been designed and will be implemented
on site to minimize the impact to the hydrological cycle. TV signal interference will be reduced as the site
selected protects the main town of Millport behind a hill. This will negate the possibility for a shadow icker
throughout the Isle of Cumbrae.
Mass Power PLC are committed to delivering safe, green power for the community of the Isle of Cumbrae
for the duration of our partnership, with the hope that in the future the door will remain open for projects
encouraging the generation of green power in Scotland, with as little impact on the natural beauty and
heritage of the Island as possible
Yours sincerely,
Callum Maxwell
Project Manager
28
36. References
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indicator/EG.USE.ELEC.KH.PC.
[2] Kendall cars. Flatbed rental, March 2014. URL: http://www.kendallcars.com/vehicles/
7-5t-flatbed/.
[3] Marshall day acoustics. Noise considerations, March 2014. URL:
http://www.seai.ie/Publications/Renewables_Publications_/Wind_Power/
Examination-of-the-Significance-of-Noise-in-Relation-to-Onshore-Wind-Farms.pdf.
[4] International electrotechnical commision IEC. Iec standards, March 2014. URL: http://www.iecex.
com.
[5] Elforsk. Cracks in onshore wind power foundations, March 2014. URL: file://M:/11_56_rapport_
screen.pdf.
[6] Scottish environment protection agency. Guidance and position statements, March 2014. URL: http:
//www.sepa.org.uk/waste/waste_regulation/guidance__position_statements.aspx.
[7] Rental Force. Bulldozer rental, March 2014. URL: http://www.rentalforce.com/bulldozers.php.
[8] gl group. Quality in manufacturing of wind turbines, March 2014. URL: http://www.gl-group.com.
[9] UK Government. Environmental regulations. UK government, London, England, 2012.
[10] Health and safety executive. Personal protective equipment, March 2014. URL: http://www.hse.gov.
uk/toolbox/ppe.htm.
[11] HI-energy. How electricity is generated in the uk, March 2014. URL: http://www.hi-energy.org.uk/
Renewables/Why-Renewable-%20Energy/How-electricity-is-generated-in-the-UK.htm.
[12] Rocky hill equipment rentals. Roller rental, March 2014. URL: http://rockyhillequipmentrentals.
com/roller-rentals/.
[13] IFC. Health and safety gengeral guidelines, March 2014. URL: http://www.ifc.org/wps/wcm/
connect/554e8d80488658e4b76af76a6515bb18/final%2B-%2BGeneral%2BEHS%2BGuidelines.pdf?
MOD=AJPERES.
[14] IRBS international. Wind turbine cost, March 2014. URL: http://www.irbs-international.com/
index.php/component/k2/item/136-wind-project-52-mw-kavarna.
[15] M. Keen. A guide to the geology of cumbrae, March 2014. URL: http://geologyglasgow.org.uk/
docs/017__074__general__Cumbrae_Island__Saturday_30_April_20112__1319376462.pdf.
[16] FIT Ltd. Feed in taris, March 2014. URL: http://www.fitariffs.co.uk.
[17] Government of Scotland. Health and safety act 1974, March 2014. URL: http://www.hse.gov.uk/
legislation/hswa.htm.
[18] Government of Scotland. Roads (scotland) act 1984, March 2014. URL: http://www.legislation.
gov.uk/ukpga/1984/54.
[19] Olex. Typical electrica 33kvl cable information, March 2014. URL: http://www.olex.com.au/
eservice/Australia-en_AU/fileLibrary/Download_540225176/Australasia/files/OLC12641_
HighVoltageCat_1.pdf.
29
37. [20] OPITO. Working at heights, March 2014. URL: http://www.uk.opito.com.
[21] RenSmart. Annual mean wind speed data, March 2014. URL: http://www.rensmart.com/Weather/
BERR.
[22] H. Riemersma ; P. Eckels; M. Barton; J. Murphy; D. Litz; J. Roach. Transformer loss study,
March 2014. URL: http://md1.csa.com/partners/viewrecord.php?requester=gscollection=
TRDrecid=0043264EAq=superconducting+transformeruid=790516502setcookie=yes.
[23] Energie schweiz. Weibull distribution t, February 2014. URL: http://wind-data.ch/tools/weibull.
php.
[24] scotlandscensus. Inhabitants of cumbrae, March 2014. URL: http://www.scotlandscensus.gov.uk/
documents/censusresults/release1c/rel1c2sb.pdf.
[25] SSE. SSE Mapping Services. SSE Mapping Services, Glasgow, Scotland, 2014.
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aspx?ETID=2catid=1046.
[27] Machiner trader. Excavator rental, March 2014. URL: http://www.machinerytrader.com/list/list.
aspx?ETID=2catid=1031.
[28] Machiner trader. Water truck rental, March 2014. URL: http://www.machinerytrader.com/list/
list.aspx?pg=2ETID=2catid=30006bcatid=4Pref=0Thumbs=1.
[29] TSG. Calculating potential carbon losses and savings from wind farms on scottish peatlands, March
2014. URL: http://www.scotland.gov.uk/Resource/Doc/917/0121469.pdf.
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download.cfm?docid=56B656A3-67EC-40F0-B036A64E5ECDFD33.
[31] unknown. Gamma function approximation, March 2014. URL: http://www.answers.com/topic/
gamma-function.
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2011_9_p16-27.pdf.
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windpowermonthly.com/article/1173200/no-big-drop-performance-turbines-older.
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toolbox/chapter-8-costs#daoc.
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dump-truck.
30
38. A Matlab codes
Hellman.m
1 %usage data=hellman(oldData,a,h,href);
2 %applies the hellman's exponent function for wind on
3 %data the oldData is wind speed at height href, data
4 %will be estimated wind speed at h and a is the
5 %hellmans's exponent for the area
6 function data=hellman(oldData,a,h,href)
7 multi=(h/href)^a;
8 data=zeros(1,(length(oldData)));
9 for i=1:length(oldData)
10 data(i)=oldData(i)*multi;
11 end
12 end
totalPower.m
1 %usage y=totalPower(A,B)
2 %B is a matrix [1,2,3,....,n]
3 %A is a matrix [1;2;3;....;n]
4 %Multiplies and adds
5 %A(1,1)*B(1,1)+A(2,1)*B(1,2)+....+A(n,1)*B(1,n)
6 function y=totalPower(A,B)
7 y=0;
8 for i=1:length(A)
9 y=y+A(i,1)*B(1,i);
10 end
11
12 end
properWind.m
1 clear all
2 close all
3
4 %Prestwick data
5
6 Pfeb2013=[47,34,16,5,10,6,10,11,8,26,21,14,11,13,6,2,8,13,10,3,3,6,10,2,3];
7 Pmar2013=[5,6,6,8,5,14,14,18,18,18,13,6,5,10,18,8,5,16,23,13,16,34,21,21,16,11,11,11,6,6,13];
8 Papr2013=[13,10,8,10,6,10,8,16,13,10,11,10,13,40,29,39,23,34,14,18,23,21,23,18,13,21,11,27,29,11];
9 Pmay2013=[18,11,26,19,19,13,8,23,19,14,21,21,32,29,14,11,8,6,5,11,23,24,24,18,10,13,21,11,10,6,11];
10 Pjun2013=[14,10,6,5,3,5,5,6,5,10,11,16,13,18,24,13,5,6,11,5,10,18,27,26,8,16,13,14,18,21];
11 Pjul2013=[21,13,11,19,16,11,8,5,5,6,3,6,10,6,13,10,8,6,6,8,10,10,6,11,6,10,6,6,10,14,10];
12 Paug2013=[13,24,23,13,10,14,8,8,16,14,21,24,10,8,14,14,18,26,21,11,13,5,6,11,5,5,8,8,13,16,27];
13 Psep2013=[27,21,14,16,10,5,13,13,5,16,11,10,8,6,31,32,26,18,16,18,13,16,3,3,8,10,3,3,6,10];
14 Poct2013=[13,19,14,6,14,14,19,23,27,6,5,10,8,8,6,10,8,8,14,11,8,19,24,18,18,18,23,21,19,19,23];
15 Pnov2013=[27,14,32,3,11,23,26,14,11,5,19,26,23,27,14,24,3,8,10,29,3,0,2,0,2,11,13,6,32,10];
16 Pdec2013=[10,10,16,23,47,14,18,29,21,23,23,24,23,34,26,27,16,34,37,34,31,34,24,43,31,14,47,34,21,16,23];
17 Pjan2014=[14,23,40,18,18,29,32,23,6,13,14,19,13,6,13,8,3,14,11,10,23,13,21,18,27,27,24,11,10,5,19];
18 Pfeb2014=[27,27,35,14];
19
20
21 wind=[0:1:40];
22
23 % Power by wind all given in KW starting at 1m/s and working up to 25m/s
24 % from respective brochures
25 gamesa11425MW=[0;110;360;670;1025;1400;1800;2150;2300;2475; ...
2500;2500;2500;2500;2500;2500;2500;2500;2500;2500;2475;2375;2075;1825;0];
26 gamesa11420MW=[0;100;350;660;1000;1325;1625;1875;1950;2000; ...
2000;2000;2000;2000;2000;2000;2000;2000;2000;2000;2000;1900;1775;1550;0];
31
