Potential Offshore Wind Energy Systems

28
Potential Offshore Wind Energy Systems By Danaraj CHANDRASEGARAN KGH070029

Transcript of Potential Offshore Wind Energy Systems

Page 1: Potential Offshore Wind Energy Systems

Potential Offshore Wind Energy Systems

By

Danaraj CHANDRASEGARAN KGH070029

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Abstract

Recent developments have shown the Malaysian government is giving serious

consideration for renewable energy sectors. Wind energy is one of solution which offers

an alternative to the fossil fuels. Furthermore, substantial investments are ploughed in to

develop the technologies for worldwide use.

In this paper, preliminary technical and economical feasibility of offshore wind

farms are investigated in the Malaysian region. This study indicates the best sites in

Malaysian region for offshore wind farms with the cost of energy calculated. Also, two

types of wind turbine models are compared to provide the better selection. In Site 2,

which corresponds to average wind speed of 4.1 m/s, the cost of energy is at RM 0.40.

Moreover, the analysis shows the feed-in tariff policy reduces the cost of energy and

increases the profitability of the wind farms.

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INTRODUCTION 4

LITERATURE REVIEW 5

Characteristics of Offshore Wind Energy Systems 5

Offshore Wind Energy Technology and Components 5

Wind Turbine Generators 6

Electrical System 6

Environmental Impacts 7

PRELIMINARY FEASIBILITY OF OFFSHORE WIND ENERGY IN MALAYSIA 9

SELECTED SITES IN MALAYSIA 14

RESULTS AND DISCUSSION 15

Comparison of selected sites 15

Comparison of WTG models 15

Sensitivity analysis 15

CONCLUSION 17

REFERENCES 18

LIST OF FIGURES AND TABLES 19

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Introduction

Wind energy systems are dynamic energy source, which are becoming more

significant in recent years. Wind energy facilities have since more than doubled

compared to yesteryears, particularly in Australian and European Continents. This trend

is expected to be followed by the rest of the world in the near future. Worldwide capacity

has reached 121 188MW in 2008 and compared to 7 480MW in 1997, signifying

substantial development in this type of energy source [1].

Pursuant to worldwide development for wind energy resources, offshore wind

energy facilities have grown in recent years. Nevertheless, this only accounts for about

1% of the total wind energy facilities and all of it is located in the European continent.

Meanwhile in Malaysia, wind energy is being given serious consideration in

future developments [2]. Rapid development in Malaysia contributes to the ever

increasing energy consumption. Malaysian government has targeted to generate 5% of

the country’s electricity by renewable energy sources, but on 0.3 % was achieved.

National Green Technology Policy launched in April 2009 seeks to provide guidance and

creating opportunities for businesses and industries towards higher economic growth.

Nevertheless, fossil fuels are expected to be dominant part of the energy mix in the future

but renewable energy sources share are expected to increase significantly.

In this paper, the technical and economical features of off-shore wind farms are

summarized and a methodology is described for evaluating the expected annual energy

yield and the cost of produced energy. This methodology is applied to six sites in the

Malaysian region, which offer promising potentials. The investigation is carried out

based selected wind turbine generator models suitable for off-shore applications.

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Literature review

Characteristics of Offshore Wind Energy Systems

Over the past decade offshore wind energy resources have emerged as potential

energy source and practiced widely in European continent. Nevertheless, its

competitiveness are being improved further and to make it feasible all over the world

[1,3].

Offshore wind energy systems are different from on-shore installation due to

several reasons:

a) Offshore wind turbines generate mote power than onshore installations

because the wind speeds are higher and steadier. In addition, the wind

turbine generators are of larger diameters and rated power.

b) The plants are inaccessible during period of high winds

c) The installation and maintenance of the facilities require high investment

cost.

d) Submarine electrical transmission to the shore is considered as a major

portion of the works involved.

In addition, offshore environment are more uncertain and difficult than onshore

sites. Therefore, it presents more costs and risks to the parties involved.

The pertinent characteristics of this energy system are further elaborated in the

subsequent sections based on Ref. [4,5].

Offshore Wind Energy Technology and Components

Development of offshore wind energy systems covers a wide range of area of

discipline such as mechanical, civil and electrical. Research and development of offshore

wind power began in 1970s and focused in Europe and United States. A summary of key

technologies involved in offshore wind farms is shown in Table 1[5].

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Wind Turbine Generators

Basically, offshore wind energy system workings are similar to the onshore

installations with distinct requirements due to the reason stated earlier. To illustrate this,

wind turbines converts the wind energy to the kinetic energy and subsequently to

electricity. However, for offshore installations, key considerations are given to the size

and reliability to maximize the energy generated.

Principle components for the offshore wind turbine are illustrated in Figure 1

based on offshore wind farm in Denmark [6]. These are mainly concerns of rotor, turbine

assembly, tower and foundation which support the tower. Rotor refers to the blades and

blade hub. Turbine assembly includes the gearbox and the generator. These are enclosed

in a shell or nacelle. Meanwhile, tower supports the turbine assembly and houses the

remaining components and facilitates the maintenance access. Apart from this,

foundation or special structure required to support the whole turbine and tower assembly.

Due to the fact that wind velocities are higher and steadier in offshore area,

offshore wind turbines are substantially larger with blade length of about 30 - 40m and

tower heights of about 60 – 80m. Apart from this factor, demanding climates and

servicing constraints need to be considered as well. Towers shall be strengthened to cope

with wind and wave loading to the structures and also the corrosive nature of the sea

environment. In addition, an offshore installation requires corrosion protections, internal

climate control systems and internal cranes for servicing.

Characteristics indicated here are only snapshots of the requirements. However,

detailed engineering are required to finalize it as it may change due to the nature of the

environment, costs and localities factors.

Electrical System

Firstly, deployment of offshore wind farms requires dedicated offshore electrical

system. This can be established by sub-sea cabling to the onshore grid from the offshore

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substation. Figure 2 shows the AC grid connection of an offshore wind farm. At the

moment, offshore grid networks are being developed in Northern Europe. In addition,

High Voltage Direct Current grid technologies are being utilised as well [7] .

Substations required for offshore installations concern with higher requirement

due to the nature of operating area and servicing conditions. For example, the following

listed have been considered and installed in an offshore wind farm substation in Denmark

apart from the switchgears and transformers; (a) Emergency diesel generator with fuel

storage; (b) Sea water-based fire-extinguishing equipment; (c) Staff and service facilities;

(d) Helipad; (e) Crawler crane; (f) MOB boat (Man Over Board) [6].

Characteristics indicated here are only snapshots of the requirements. However,

detailed engineering are required to finalize it as it may change due to the nature of the

environment, costs and localities factors.

Environmental Impacts

As with any other potential energy source, environmental impacts are also given

substantial considerations as well. Nevertheless, wind energy is described as green

energy irrespective it’s either on the land or offshore. Currently, environmental studies

are conducted prior to the construction and subsequently any resulting recommendation

will implemented during the succeeding project phase. The following paragraphs

summarize the potential environmental consideration during the development and

operation of the offshore wind energy installations [7,8].

During construction phase, sedimentation, noise and vibration will be the

concerns. Technologies are available to mitigate these impacts and preparation of

component away from the wind site also helps. In addition, oil spills and other

contaminants also present risks to water quality.

Impacts on marine life and birds have to be evaluated diligently. At times,

foundation supports may act as an artificial reef and promote species around it. However,

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this may also stimulate the bird population, subsequently resulting in collision between

the towers and birds. In addition, it also has similar consequences towards migrating

birds by causing navigational disorientation. Wind farms also can diminish essential

habitats for seabird, as they have restricted areas which thay can successfully feed.

Electromagnetic fields due to the submarine cabling, support pilings and anchoring

devices may also affect the underwater species and diminish its habitat. For example, this

may affect fish’ perception of electric and magnetic field for orientation and prey

detection.

Another concern would be the visual impact of the wind turbine installations.

However, this impact diminishes as the distance to the shores increases. Also, the wind

turbines may interfere with shipping routes, fishing areas and recreational uses of the

selected area.

Therefore, environmental impacts need to be studied prior and subsequent

recommendation taken into account to ensure proper mitigation of suspected impacts.

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Preliminary Feasibility of Offshore Wind Energy in Malaysia

In the succeeding sections, the main technical and economical aspects for offshore

wind farm developments are appraised. The methodology of the appraisal is based on

Ref. [9].

Annual energy yield assessment, E

The evaluation of annual energy, E (GWh/ year) for an offshore wind farm requires the

following steps.

a) Offshore wind flow prediction.

Predictions of wind flow for a particular site plays a crucial role in determining

the feasibility of the project. Therefore, a detailed knowledge of wind characteristics and

historical data is required for efficient planning and implementation of wind farms. These

data can be sourced from meteorological department of the locality and marine surface

observation reports. For this study, the wind flow data is obtained from Ref. [10]. Sites

selected are shown in Figure 3 and the water depth of the sites is indicated in Figure 4.

b) Gross energy assessment

Gross energy , EG (GWh/ year) contributed by each of the wind turbine can be

calculated using software tools with wind flow information and the wind turbine

generators (WTGs) power curve. In this paper, the HOMER software used considering

the WTGs power curves, prevailing wind directions and the Weibull distribution

parameter on the basis of values in Table 2 and Ref [10].

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c) Wind farm design

Offshore wind farm layouts can be optimized for energy generation. However, the

water depth and sea bed conditions shall be considered as well to reduce the overall

project costs.

In this paper, the available space is assumed to be 2km2. Layout is composed by

arrays with distance between columns (dc) and rows (dr) of 8D and 6D. With these

assumptions, the number of WTGs in the wind farm can be summed as:

N = A/ (48. D2)

Also, the array efficiency, ηL if often assessed using software tools considering

the sheltering effects of the WTGs and wind flow characteristics. In this paper, the value

is assumed at 0.9.

d) Wind farm electrical system

Based on Ref. [9], an AC 20kV transmission line is the best solution for a wind

farm size of 10-20 MW with estimated distance to coast of 0.5 – 2.0 km. Considering the

same case for this paper, the electrical transmission losses coefficient ηE is expressed as:

ηE = 0.98 – (d/ 600)

with d is distance to shore (km)

e) Wind farm availability, ηA

Wind farm availability, ηA refers availability of the plant to produce electricity in

percentage. Studies have shown that availability of the plant has significant effect on the

costs of electricity. Hence, the system shall be sufficiently designed using high quality

and reliable components. Overall, wind farm availability considers both electrical system

availability and WTGs availability. In this paper, the availability is assumed to be 95% of

the annual energy yield.

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On the basis of previous assumptions, the annual gross energy yield, E (GWh/

year) can be summed as

E = EG x N x ηL x ηE x ηA

Investment, operation and maintenance costs

The evaluation of economical aspects for offshore wind energy system is described

here and estimated investment and costs are provided. The total investment costs

comprised of the following items.

a) Wind turbine costs, CT

The costs include the tower, shell and electrical devices of the WTGs. It mainly

depends on the size, hub height of the WTG and particularly increases to adapt the WTGs

to the sea conditions. For this study, value of CT is in the range of RM 3,750,000 to

4,500,000/ MW, according to literature data is assumed.

b) Support and installation costs, CS

This cost comprises of material, construction and installation cost. The foundation

material cost is factored by hub height and site conditions such as water depth and

climate. Meanwhile the installation cost is a function of number of WTGs erected. For

the present study this costs is expressed as

CS = (H/0.5) 0.3 [(1700 W2

- 9455W+ 21836)/ 1000]

Where, W = water depth

H = WTG hub height

c) Grid Connection Cost, CG

Grid connection costs is subject to the distance involved to the onshore point, type of

transmission system and the electrical system within the wind farm. The cost of 20kV/

150kV transformer is assumed of RM42,500/ MW and the additional costs of other

devices is of RM500,000/ MW, according to literature data.

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d) Operation and Maintenance Cost, CM

This cost is ties up with the overall operational and maintenance strategy employed by

the plant operator. In addition, distance from shore points and plant reliability influences

it as well. Here, value of RM250,000/ MW is considered, according to literature data.

e) Project and Development Cost, CP

The project and development cost is assumed to be 4% of the investment cost.

On the basis of previous assumptions, the total investment cost, I can be summed up as:

I = N [PR (CT + CG + CM +CP) + CS]

Where PR is the WTG rated power

f) Operation and Maintenance Annual Cost, O

For this study, the annual O & M cost is assumed to be 2% of the total investment, I.

Economical Feasibility

This section described the methodology to calculate the costs of energy from the

offshore wind farm.

The total operating cost is the sum of the annual operation and maintenance

(O&M) costs, total fuel cost, and annualized replacement cost minus the annualized

salvage value. For grid-connected systems, the operating cost includes the annualized

cost of grid purchases minus grid sales.

The total net present cost of a system (NPC) is the present value of all the costs

that it incurs over its lifetime, minus the present value of all the revenue that it earns over

its lifetime. Costs include capital costs, replacement costs, O&M costs, fuel costs,

emissions penalties, and the costs of buying power from the grid. Revenues include

salvage value and grid sales revenue. This can be summed as:

NPC = Total annualized cost of the system/ CRF

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Where, CRF = Capital recovery factor = i(1+i)n/[(1+i)

n – 1]

i = discount rate

n = number of years

Levelized cost of energy (COE) is defined as the average cost per kWh of useful

electrical energy produced by the system. To calculate the COE, the annualized cost of

producing electricity (the total annualized cost minus the cost of serving the thermal load)

divided by the total useful electric energy production. Therefore COE can be summed up

as:

COE = Total annualized cost of the system/ Total electricity produced.

For this study, the economic parameters are defined in Table 3.

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Selected Sites in Malaysia

The main parameters of selected sites for this study are described in Table 2.

These sites face the South China Sea and present a potential offshore wind resource.

Figure 3 shows the sites, indicated by numerical identification of 1, 2, 3, 4, 8 and 13.

Wind speeds at these sites reach more than 5 m/s during the northeast monsoon season

and the rest of the year marked low. The directions of the wind are from the northeast and

east quadrant during the northeast monsoon season and south and southwest during the

southwest monsoon season [10].

Currently, there is no available precise bathymetry survey conducted in South

China Sea concerning these sites. Also, a general survey shown in Figure 4 indicates the

water depth for the sites are less than 50m. However, for the purpose of this study, the

wind farms are estimated to be 20m water depth, within a distance of 5km from the shore.

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Results and discussion

Comparison of selected sites

The economic feasibility analysis described in the preceding sections is applied

on the selected sites in Malaysia described in Table 2, considering the wind turbine

models described in Table 4.

The results are tabulated in Table 5. The lowest cost of energy system is achieved

at Site 2. Meanwhile, highest cost of energy system is found on Site 8. This is due to the

differences in the wind resources available in the particular site.

Figure 5 shows the monthly average electricity production in Site 2 using both

WTG models. The results confirm that electricity production is highest during the

northeast monsoon season and low for the rest of the year.

Comparison of WTG models

For all the sites, two models of WTGs were assessed. The results are shown in

Table 5 as well. It results that larger sized WTG produces higher energy output compared

to the smaller sized WTG, corresponding to Site 1, 4, 8 and 13. However, the variances

are between the two models is less than 5%. Meanwhile, net specific production results in

having smaller rated WTG with higher value for all sites as shown in Figure 6. Table 6

shows the COE, for both models of WTG in all the investigated sites. The results

confirm that the higher rated WTGs are more competitive at approximately 33% lower

against the lower rated WTGs, due to their lower energy system cost.

Sensitivity analysis

The influence of the feed-in tariffs in the cost of energy for Site 2 and for the V-

80 WTG model is explored in the sensitivity analysis. Table 7 describes the variation of

the cost of energy as a function of feed-in tariff. The initial values in the table are those

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considered in Table 7. The analysis shows that feed-in tariff ratio of 2.38 would represent

the break even point for the energy system cost. Any subsequent increase in feed-in tariff

ratio would be present an attractive climate for private sectors to invest.

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Conclusion

In this paper, a preliminary feasibility study of offshore wind farms to 6 selected

sites in Malaysia was conducted. The results indicate that Site 2 as the best location due

high wind resources availability.

The 2 MW rated wind turbines, provides the lowest energy cost at RM0.40.

However, higher net specific production is provided by the 0.66 MW rated wind turbine.

The sensitivity analysis confirms that the feed-in tariff is a significant factor in

determining the feasibility of the offshore wind farm in Malaysia. Feed-in tariff higher

than the break even point would attract private sectors to invest on this type of energy

system. Nevertheless, the uncertainty in the renewable energy policies and wind farm

availability shall make it difficult to forecast the cost of energy for this type of

applications.

In summary, the main obstacle in the Malaysian offshore wind farm deployment

would be the feed-in tariff policy. An attractive policy would determine the profitability

of an investment in the offshore wind farms and encourage private sectors to invest here.

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References

[1] World Wind Energy Association. “World Wind Energy Report 2008”. February

2009

[2] Tick Hui Oh, Shen Yee Pang, Shing Chyi Chua. “Energy policy and alternative

energy in Malaysia: Issues and challenges for sustainable growth”. Renewable

and Sustainable Energy Reviews, Vol. 14, pp1241–1252, 2010.

[3] Gaetano Gaudiosi. “Offshore Wind Energy Prospects”. Renewable Energy, Vol.

16, pp828-834, 1999.

[4] Minerals Management Service, U.S. Department of the Interior. “Wind Energy

Potential on the U. S. Outer Continental Shelf”. May 2006.

[5] Wang Zhixin, Jiang Chuanwen, Ai Qian, Wang Chengmin. “The key technology

of offshore wind farm and its new development in China”. Renewable and

Sustainable Energy Reviews, Vol. 13. pp216–222, 2009.

[6] Dong Energy. (undated). [Online]. Viewed 2010 March 15. Available

http://www.hornsrev.dk/

[7] Brian Snyder, Mark J. Kaiser. “Ecological and economic cost-benefit analysis of

offshore wind energy”. Renewable Energy, Vol. 34, pp1567–1578, 2009.

[8] European Wind Energy Association. “Oceans of Opportunity: Harnessing

Europe’s largest domestic energy resource”. September 2009.

[9] Antonio Pantaleo, Achille Pellerano, Francesco Ruggiero, Michele Trovato.

“Feasibility study of offshore wind farms: an application to Puglia region”. Solar

Energy, Vol. 79, pp321-331, 2005.

[10] E. P. Chiang, Z. A. Zainal, P. A. Aswatha Narayana and K. N. Seetharamu.

“Potential of Renewable Wave and Offshore Wind Energy Sources in Malaysia”.

Marine Technology Seminar, pp1-7, 2003.

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List of Figures and Tables

Figure 1 - Offshore Wind Turbine Installation

Figure 2 - AC grid connection of an offshore wind farm.

Figure 3 -Selected Offshore Wind Farm Sites

Figure 4 - Bathymetry for South China Sea Areas

Figure 5 - Monthly Average Electric Production

Figure 6 - Net Specific Production for Different Sites

Table 1 - Key Technologies of Offshore Wind Farm [5]

Table 2 - Main Parameters of Selected Site

Table 3 - Economic Parameters

Table 4 - Main Wind Farm Parameters

Table 5 - Investment and O & M Costs

Table 6 - Energy Costs

Table 7 - Sensitivity Analysis for V-80 model, Site 2

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Figure 1 - Offshore Wind Turbine Installation

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Figure 2 - AC grid connection of an offshore wind farm.

Figure 3 -Selected Offshore Wind Farm Sites

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Figure 4 - Bathymetry for South China Sea Areas

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Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec0

2,000

4,000

6,000

8,000

Po

we

r (k

W)

Monthly Average Electric Production

Wind

Grid

V-47

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec0

2,000

4,000

6,000

8,000

Po

we

r (k

W)

Monthly Average Electric Production

Wind

Grid

V-80

Figure 5 - Monthly Average Electric Production

Net Spec Production for Different Site

0

200

400

600

800

1000

1200

1400

1600

1 2 3 4 8 13

Site

MW

h/

MW

V-47 V-80

Figure 6 - Net Specific Production for Different Sites

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Table 1 - Key Technologies of Offshore Wind Farm [5]

Key technologies Contents and characteristics

1. Foundations 1. Bearing hydrodynamic and aerodynamic load, considering factors as wind and wave load, support construction

and dynamic characteristics of wind turbines and response to unit control system etc.

2. Types of foundations: (1) gravity, mature construction and installation technologies, suitable for water depths

about 0–10 m. The disadvantages are seabed needed and hard to remove with large weight and size; (2) mono pile

foundation, no need of seabed preparation, simple to manufacture, be considered for depth of 0–30 m. The

disadvantage is special installation equipment is needed. (3) tripod foundation, seabed preparation is little needed,

suitable to water depths higher than 20 m.

3. IEC61400-3 based

2. Selection of site Considered factors: (1) wind resources; (2) permission to project construction; (3) rights of using farm site; (4) grid

situations, location and voltage levels of transformer station, accessible largest capacity and grid plan, etc.; (5) sites

situations, scope, water depths, wind resources and marine geological conditions; (6) environment constraints.

Negative impact on tourism, birds, fishing and coast defense.

3. Wind measurement (1) Primary evaluation of wind resources: evaluate power generation through weather station, oil drilling platform, etc.

(2) Installing wind measure tower about 50–80 m or beacon wind measurement. In addition, Ultrasonic radar wind

measurement instrument can also be adopted. Its character is that the installation is under the low plane and

measurement is on the flow platform.

4. Investigation (1) Sonar is used to survey sites, water depths, and drawing water depths maps. These provide basis for microsite and

design of outlines; (2) collecting soil data of surface layer; (3) seabed exploration drilling depth is 20–40 m under sea

geological conditions. (4) Measured waves, tides and currents and other data used to calculate the foundation of

hydrodynamic loads of underwater structures.

5. Wind turbines of offshore (1) Greater diameter and lower rated speed of the same rated power generating units; (2) the little rate of change of

wind farm wind speed with the variable height; (3) the speed of units increase by 10–30%. Power generation is increased and

torque is decreased as well as decreased weight and cost of system; (4) corrosion protection standards are enhanced,

such as internal closed measurement. In addition, dehumidification equipment is installed in the cockpit and tower; (5)

new structures are used, which include double-blades, down wind direction, high-voltage transmission, etc.

6. Hoisting Slifting vessels currently used are mainly modified boats. A2SEA modified ship, mayflower ship , jump-firecrackers are

in operation. Among them, mayflower ship is constructed by Shanghaiguan shipyard. It has 6 extendable stents and

35 m operation deep, and can be installed at the base without assistance. Moreover, the whole lifting and installation

method has been adopted.

7. Electrical transmission (1) Offshore wind turbines are arranged in a certain way with the information of an independent group series

technology connected with booster substations. Silicon resin cooling transformer is specially developed with good sealing

property. (2) HVDC is used to decrease network loss and improve power quality.

8. Access and stability Network access and grid-connection technology of offshore wind farm, which includes stability of grid, reliability and

operation of system control strategy.

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Site Air

Density

Weibull k

parameter

Average

Wind

Speed

Available

Area

Mean

Water

Depth

Coast

Distance

kg/ m3 m/ s km

2 m km

1 1.08 2 3.5 2 20 2

2 1.08 2 4.1 2 20 2

3 1.08 2 3.8 2 20 2

4 1.08 2 3.3 2 20 2

8 1.08 2 3.1 2 20 2

13 1.08 2 3.8 2 20 2

Table 2 - Main Parameters of Selected Site

Parameter Value (unit)

Economic lifetime 20 years

Discount rate 4%

Electricity Price RM 0.29

Feed-in- Tariff RM 0.29

* corresponds to Malaysian Industrial

Tariff and current policy

Table 3 - Economic Parameters

Parameters Vestas

V-47

Vestas

V-80

Rated power (kW) 660 2000

Rotor diameter (m) 47 80

Hub height (m) 50 78

Number of WTGs 19 7

Availability 0.95 0.95

Array efficiency 0.93 0.95

Transmission efficiency 0.978 0.978

Plant size (MW) 12.54 14

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Table 4 - Main Wind Farm Parameters

Description Vestas

V-47

Vestas

V-80

Investment cost (RM) 162,828,000 132,750,000

CT (%) 36 56

CS (%) 50 26

CG (%) 9 10

CM (%) 2 3

CP (%) 3 5

O&M cost (RM/yr) 3,258,000 2,658,000

Table 5 - Investment and O & M Costs

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Site Model Wind

Farm

Capacity

Initial capital Operating cost Total NPC COE E Net Specific

Production

MW RM RM/ year RM

RM/kWh kWh/ yr MWh/ MW

1 V-47 12.54 162,828,000 614,232 154,480,404 0.85 13,445,249 1,072

1 V-80 14 132,750,000 871,438 83,294,371 0.64 13,451,246 961

2 V-47 12.54 162,828,000 1,439,335 97,132,399 0.55 18,286,012 1,458

2 V-80 14 132,750,000 1,856,770 69,903,402 0.40 18,225,138 1,302

3 V-47 12.54 162,828,000 628,527 108,151,545 0.77 14,357,679 1,145

3 V-80 14 132,750,000 1,043,950 80,949,874 0.58 14,287,065 1,021

4 V-47 12.54 162,828,000 472,174 123,110,393 1.40 9,024,842 720

4 V-80 14 132,750,000 20,300 94,861,629 1.04 9,327,512 666

8 V-47 12.54 162,828,000 806,762 127,657,583 1.77 7,403,764 590

8 V-80 14 132,750,000 309,527 99,344,070 1.32 7,729,525 552

13 V-47 12.54 162,828,000 599,816 108,541,727 0.79 14,218,581 1,134

13 V-80 14 132,750,000 1,030,091 81,137,637 0.59 14,220,128 1,016

Table 6 - Energy Costs for Selected Sites

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TNB - Commercial

Sellback

(RM/kWh)

COE

(RM/kWh)

Feed-In Tariff

Ratio

0.29 0.40 1.00

0.43 0.25 1.50

0.58 0.11 2.00

0.68 0.01 2.35

0.68 0.00 2.38

0.69 -0.01 2.40

0.71 -0.02 2.46

0.72 -0.04 2.50

0.73 -0.05 2.54

0.77 -0.08 2.67

0.78 -0.10 2.71

0.86 -0.18 3.00

Table 7 - Sensitivity Analysis for V-80 model, Site 2