AIN SHAMS UNIVERSTY

FACULTY OF ENGINEERING

DEPARTMENT OF ELECTRICAL POWER AND MACHINES

ENGINEERING

Application of Geographic Information System (GIS) for

Appropriate Site Selection of Wind Farms

A thesis submitted in partial fulfillment of the requirements for the degree of

MASTER OF SCIENCE

In

ELECTRICAL ENGINEERING (Power and Machines)

By:

Amany Belal Mohammed Ahmed

B.Sc. in Elect. Eng., Ain Shams University

SUPERVISED BY:

Prof. Almoataz Youssef Abdelaziz

Dr. Said Fouad Mekhamer

Department of Electrical Power and Machines Engineering

Faculty of Engineering, Ain Shams University

CAIRO 2013

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Summary

Title: Application of Geographic Information System (GIS) for

Appropriate Site Selection of Wind Farms

This thesis presents an application of geographic information systems (GIS)

to the site selection of wind farms. The proposed methodology exploits the

extensive capabilities of GIS software in analyzing several forms databases

especially maps.

Throughout this work, the data collection process has spanned several data

sources including maps, the Egyptian wind atlas, the unified grid data, etc. The

constraints applied in wind farm planning have been presented in the form of

GIS layers and a sequential filtering procedure was utilized to clip out the

unsuitable sites. The main constraints for wind farm site selection applied to this

work are: wind speed, national electricity grid, main roads, land height, urban

areas, and Airport locations, historical places, ports, water network, and oil lines

and Petrol tanks.

In addition of using GIS for wind farm site selection, the effect of a proposed

wind farm connection to the unified grid has been studied using ETAP software

regarding load flow and short circuit. For these studies, the Canal Zone and red

sea shore area have been modeled. The existing and proposed wind farms have

also been presented through a machine level model.

This thesis consists of five chapters, as follows:

Chapter1:

This chapter defines the main concepts of wind energy, its technology

developments, criteria of wind farm location and the connection to the power

grid, economic concepts and existing wind farms in Egypt.

Chapter2:

In this chapter we discuss wind spreading and its connection to the

geographic location, the general steps for establishing wind farms and the

related studies, the types of wind turbines and the suitable generators and the

impact of wind projects on the environment.

Chapter3:

In this chapter, the main concepts of the Geographic Information System are

introduced, its benefit, usage, creation, and how to collect and classify data. The

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chapter contains a study of wind resources in Egypt, creation of the wind atlas

of Egypt, and its application to selecting the appropriate locations for wind

farms.

Chapter4:

A study was made in this chapter to decide how to connect the proposed wind

farms with the unified grid and the different studies needed to achieve such

objective. An ETAP model was build to study the effect the wind farms on the

power and short circuit level in unified grid.

Chapter5:

This chapter includes conclusions, recommendation, and further

investigations.

Keywords:

GIS, geographic Information system, wind energy, wind farm, planning, site

selection, ETAP, power flow, short circuit.

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Table of Contents

Chapter 1 : Wind Power

1.1 Introduction 1

1.2 Development of Wind Energy Technology 1

1.3 Wind Power in the World 2

1.4 Wind Energy in Egypt 6

1.5 Economics of wind energy 7

1.6 Construction of the Wind Turbine 8

1.7 Rotor Speed Control 9

1.8 Generator Frequency Control 10

1.8.1 Pole changing induction generators 10

1.8.2 Multiple gearboxes 10

1.8.3 Variable slip induction generators: 10

1.8.4 Indirect Grid Connected Systems: 11

1.9 Wind Farms 11

1.10 Wind Farm Location Planning 13

1.11 Other Considerations on Wind Farm Site Selection (7) 15

Chapter 2 : Human efforts for the extraction of power from wind

2.1 Introduction 17

2.2 Wind Resources 19

2.3 Geographic variation in wind resources 20

2.4 Availability of wind energy 20

2.5 Turbulence 21

2.6 Wind Farms development 22

2.6.1 Wind farm site selection considerations 23

2.6.2 Visual impact 24

2.6.3 Shadow flicker 24

2.6.4 Noise 25

2.6.5 Electromagnetic Interference EMI 25

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2.6.6 Ecological assessment 26

2.7 Components of a Wind Project 27

2.7.1 Wind Turbines 27

2.7.2 Electrical Collection System 28

2.7.3 Transmission System 28

2.7.4 Access Roads 29

2.7.5 Operations and Maintenance (O&M) Facility 29

2.8 Types of wind turbines 29

2.8.1 The Vertical Axis Turbine 29

2.8.2 The Horizontal Axis Turbine 31

2.9 Wind Power 32

2.10 Tower height impact on wind power 34

2.11 Rotor efficiency 36

2.12 Wind turbines generators 41

2.12.1 Synchronous Generators 41

2.12.2 The Induction Generator 42

2.13 Speed Control for Maximum Power 43

2.14 Average power in the wind 46

2.15 Wind turbine performance calculations 47

2.15.1 Idealized wind turbine power curve 48

2.15.2 Optimizing Rotor Diameter and Generator Rated Power 49

2.16 Environmental Impacts of wind turbines 50

Chapter 3 : GIS usage for wind farms in Egypt

3.1 Introduction 52

3.2 Egyptian wind energy resources 53

3.3 Geographic Information System (GIS) 53

3.4 Benefits of GIS 55

3.5 GIS Usage: 56

3.6 GIS Feature Class: 59

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3.6.1 Point Feature Class 59

3.6.2 Line Feature Class 59

3.6.3 Polygon Feature Class 60

3.7 Creating GIS 61

3.8 Making GIS accessible 61

3.9 Wind Potential Analysis 62

3.10 Data Collection 63

3.10.1 Smart Layers for Smart Maps 63

3.10.2 Site Scouting Field Trip 64

3.11 Wind Atlas 65

3.12 Wind Energy 66

3.13 Wind Energy in Egypt 67

3.14 Wind Resources in Egypt 68

3.15 Wind Climate of Egypt 69

3.16 The topographical Inputs 70

3.17 Height Contour Maps 71

3.18 Roughness Maps 71

3.19 Wind Mapping 73

3.20 Geographic coordinate System 73

3.21 Map Projection 73

3.22 Map Scales 75

3.23 Used Layers 76

3.24 Processing the used layers 77

Chapter 4 : Planning Wind Farms

4.1 Introduction 84

4.2 Wind Farm Products 85

4.3 Wind Power Integration 85

4.3.1 Integration of large wind farms 87

4.4 Selection of Wind Power Technology 89

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4.5 Smoothing of the Power Generation 91

4.6 Power Duration 92

4.7 Influence of wind fluctuations on the grid 93

4.8 Transmission System Congestion 93

4.9 Technical Possibilities of Frequency Control with Wind Power Plants 94

4.10 Voltage Stability 95

4.11 Wind Power Plants Effect on Transient Stability 96

4.12 System Studies Required for Wind Power Integration 98

4.12.1 Load Flow Study 98

4.12.2 Short Circuit Study 99

4.12.3 Harmonics Study 99

4.12.4 Insulation Coordination Study 100

4.12.5 Flicker and Voltage Fluctuation Study 100

4.12.6 Dynamic Stability Study 101

4.12.7 Safety Earthing Study 101

4.12.8 Neutral Grounding Study 102

4.12.9 Protection Coordination Study 102

4.12.10 Electromagnetic Field (EMF) Study

103

4.13 Wind Energy Economic Evaluation 103

4.14 ETAP Model Creation 104

4.14.1 Selecting the Model Zone 104

4.14.2 Developing the Model 10 5

4.15 Power Flow Study 107

4.15.1 Power Flow Study before adding the wind farm 107

4.15.2 Power Flow Study after adding the wind farm 108

4.16 Fault Study 109

4.16.1 Fault Study before adding the wind farm 109

4.16.2 Fault Study after adding the wind farm 111

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Chapter 5 : Conclusion

5.1 Introduction 113

5.2 Geographic Information System Software 113

5.3 GIS Application in Wind farm Site Selection 114

5.4 Processing Layers 115

5.5 Power Flow and Short Circuit Studies 115

5.5.1 Power Flow Study 116

5.5.2 Short Circuit Study 116

5.6 Recommendation for further investigation 116

References 118

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List of Figures

Figure ‎1.1: World total installed capacity. ............................................................................. 3

Figure ‎1.2: Impact of tower spacing and array size on performance of wind turbines. .......... 12

Figure ‎1.3: Optimum spacing of Wind Turbine towers ........................................................ 13

Figure ‎1.4: Typical Power Curve of a Wind Turbine ........................................................... 14

Figure ‎1.5: Number of Hours per Year for Different Wind Speed Bins, H(Ui) ..................... 14

Figure 2.1: Interference Mechanisms of Wind Turbines with Radio Systems. ...................... 26

Figure ‎2.2: Wind turbine component ................................................................................... 26

Figure ‎2.3: Horizontal and vertical axis wind turbines. ....................................................... 29

Figure ‎2.4: Power in the wind, per square meter of cross section, at 15o C and 1 atm. .......... 33

Figure ‎2.5: Showing the approximate area of a Darrieus rotor. ............................................ 34

Figure ‎2.6: Increasing wind speed and power ratios with height for various friction

coefficients α.…35

Figure ‎2.7: Wind turbine stream tube. ................................................................................. 37

Figure ‎2.8: Blade efficiency variation with the downstream to upstream wind speed value. . 39

Figure ‎2.9: Rotors efficiency variation according to its Tip Speed Value. ............................ 41

Figure ‎2.10: A three-phase synchronous generator. ............................................................. 42

Figure ‎2.11: Blade efficiency variation with different rotation speed. .................................. 43

Figure ‎2.12: Example of the impact that a three-step rotational speed on delivered power.. . 44

Figure ‎2.13: Variable-frequency output of the asynchronous generator................................ 45

Figure ‎2.14: The combination of actual wind and the relative wind due to blade motion...…47

Figure ‎2.15: Increasing the angle of attack can cause a wing to stall. ................................... 48

Figure ‎2.16: Idealized power curve...................................................................................... 48

Figure ‎2.17: (a) Increasing rotor diameter reduces the rated wind speed, (b) Increasing the

generator size increases rated power. ................................................................................... 50

Figure ‎3.1: The increase of wind generation in Egypt. ......................................................... 53

Figure ‎3.2: Methods to represent line features. .................................................................... 60

Figure ‎3.3: representing surface shapes in GIS. ................................................................... 66

Figure ‎3.4: mean meridional circulation of wind. ................................................................ 68

Figure ‎3.5: Mean wind speeds and power densities.............................................................. 69

Figure ‎3.6: Contour maps. ................................................................................................... 71

Figure ‎3.7: Estimated mean power production of a 450-kW wind turbine. ........................... 72

Figure ‎3.8: Map projection. ................................................................................................. 74

Figure ‎3.9: Base map of Egypt. ........................................................................................... 77

Figure ‎3.10: Wind speeds of Egypt. ..................................................................................... 78

Figure ‎3.11: choosing the Area Of Interest (AOL). .............................................................. 78

Figure ‎3.12: selecting the Area Of Interest (AOL) layers. .................................................... 79

Figure ‎3.13: clipping the Area Of Interest (AOL). ............................................................... 79

Figure ‎3.14: first stage of the flow chart. ............................................................................. 81

Figure ‎3.15: second stage of the flow chart. ......................................................................... 82

Figure ‎3.16: suitable sites in case of wind speed ≥ 6 m/s. .................................................... 83

Figure ‎3.17: suitable sites in case of wind speed ≥ 7 m/s. .................................................... 83

Figure ‎4.1: induction generator. ........................................................................................... 89

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Figure ‎4.2: double fed induction generator. ......................................................................... 90

Figure ‎4.3: Converter interfaced Gear less, multi pole generator. ......................................... 90

Figure ‎4.4: Power duration curve of total wind power feed-in, Germany 2000. .................... 92

Figure ‎4.5: Egyptian Unified Power Network 2012. .......................................................... 105

Figure ‎4.6: Canal Zone Power Network. ............................................................................ 105

Figure ‎4.7: Part A1 of Canal Zone Power Network. ........................................................... 105

Figure ‎4.8: Part A2 of Canal Zone Power Network. ........................................................... 105

Figure ‎4.9: Part A3 of Canal Zone Power Network. ........................................................... 105

Figure ‎4.10: Part A4 of Canal Zone Power Network. ......................................................... 105

Figure ‎4.11: Part A5 of Canal Zone Power Network. ......................................................... 105

Figure ‎4.12: Part A6 of Canal Zone Power Network. ......................................................... 105

Figure ‎4.13: Gabl Elzeit wind farm. .................................................................................. 105

Figure ‎4.14: Ras Ghareb wind farm. .................................................................................. 105

Figure ‎4.15: Transmission line editor ( info ). .................................................................... 106

Figure ‎4.16: Transmission line editor ( impedance ). ......................................................... 106

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List of Tables

Table ‎1.1: Installed wind power capacity (MW) .................................................................... 5

Table ‎1.2: Technical and Economical Renewable Electricity Generation Potentials in Egypt

(TWh/year) ........................................................................................................................... 7

Table ‎2.1: wind power classes at height of 50m ................................................................... 21

Table ‎2.2: Typical Breakdown of Costs for a 10 MW Wind Farm ....................................... 22

Table ‎2.3: Friction Coefficient for various terrain characteristics ......................................... 35

Table 4.1: power flow without wind farm ……………………………………….…………107

Table 4.2: power flow with wind farm ……………………………………………………..108

Table 4.3: Fault in Zafrana1 without wind farm ………………………………..………….109

Table 4.4: Fault in Zafrana2 without wind farm …………………………………..……….110

Table 4.5: Fault in Safaga without wind farm ……………………….……………….…….110

Table 4.6: Fault in Hurgada without wind farm ……………………………..……….…….110

Table 4.7: Fault in Zafrana1 with wind farm …………………..…………………….…….111

Table 4.8: Fault in Zafrana2 with wind farm ………………………………..……….…….111

Table 4.9: Fault in Safaga with wind farm ………………………………………..….…….111

Table 4.10: Fault in Hurgada with wind farm ………………………………….…….…….112

Table 4.11: Fault in Gabal Elzeit with wind farm ………………………………………….112

Table 4.12: Fault in Ras Gharib with wind farm …………………………………...………112

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List of Symbols

Latin letters

A rotor swept area

Cp Power coefficient of the turbine

D Blade or rotor diameter

E energy yield of a wind turbine

H Height of the turbine tower

H(νi) number of hours in wind speed bin νi

K.E. kinetic energy

P Power output of a wind turbine

Pb power extracted by the blades of the turbine

P(νi) power output of the wind turbine at wind speed νi

Pw Power in the wind

m.

mass flow rate

n Number of wind speed bins

TSR Tip-speed ratio

VC Cut in wind speed

VF Furling or cut out wind speed

VR Rated wind speed

Greek Letters

α friction coefficient of the terrain

λ ratio of downstream to upstream wind speed

ρ density of air

ν wind velocity at height H

ν0 wind velocity at height H0

νb wind through the plane of the rotor blades

vd wind velocity downstream the wind turbine

1

Chapter 1

Wind Power

1.1 Introduction

Wind power is obtained by converting of the kinetic energy of the wind into a

useful form of energy. If the mechanical energy is used directly by machinery,

such as g water pumps or grinding stones, the machine is called a windmill. If

the mechanical energy is converted to electricity, the machine is called a wind

turbine or a wind energy converter (WEC).

A wind farm is a group of wind turbines in the same location used for large

scale production of electric power. In a wind farm, the individual turbines are

interconnected by a medium voltage – usually 30 to 36kV – network to collect

power and deliver it to a substation. At the substation, this medium voltage

power undergoes a voltage increase using transformers so that it can be

connected to the high voltage transmission system. The control and protection

of wind farms is achieved through a communication network that links the

metering and control devices installed at each turbine to the control centre.

1.2 Development of Wind Energy Technology

The first electricity generating wind turbine was a battery charging machine

installed in 1887 in Scotland. In 1891, the first wind turbine that generated

electricity for direct use was built in Denmark. The first grid connected wind

turbine was in service at Yalta, USSR in 1931. This was a 100 kW generator

connected to the local 6.3 kV distribution system. The first megawatt class wind

turbine synchronized to the grid was an experimental 1.25 MW unit at Vermont

USA.

After World War 2, the interest in large scale wind power generation declined.

Only small-scale wind turbines for remote-area power systems received some

interest. With the oil crisis at the beginning of the 1970s, the interest in wind

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power generation returned. As a result, financial support for research and

development of wind energy became available.

The wind energy technology has improved gradually since the early 1970s. At

the end of 1989, a 300kW wind turbine with a 30-meter rotor diameter was state

of the art. Only 10 years later, 2MW turbines with a rotor diameter of about 80

meters were available. In 2004, 3 MW turbines were in service [1]. By the end

of 2009, the world's largest turbine could generate up to 7.5 Megawatts of

energy per turbine [2]. In 2010, a prototype 10 MW wind turbine with a height

of 162.5 m and a rotor diameter of 145 m was announced in Norway [3].

The major factors that have accelerated the development of wind power

technology are:

Falling prices of the power electronics associated with wind power

systems

Economies of scale as the turbines and plants are getting larger in size.

Accumulated field experience has improved the possible wind farms

capacity factors up to 40%.

Development of high-strength fiber composites led to the construction

of large, low-cost blades

Wind Power in the World

In the early 1970s, the oil price shock triggered the interest in the utilization of

wind power to provide electrical energy. Twenty years later, wind energy

gained an escalating momentum due to the hazardous effects of fossil fuel and

nuclear power plants on the environment and the expected depletion of fossil

fuel resources within the next 50 years.

At the end of 2009, the installed capacity of wind-powered generators was

about 160 GW producing 340 TWh of electrical energy. This amount of energy

is equal to 2% of global electricity consumption. World wind generation

capacity increased more than 4 times between 2000 and 2006. Since 2004, the

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average growth in new installations has been 27.6% each year. The increasing

trend of wind power generating capacity continues as shown in Fig. 1.1.

Figure 1.1: World total installed capacity.

In terms of economic value, the wind sector had a turnover of 70 billion US$

and employed 550,000 persons worldwide in 2009 [4]. Wind power share in the

energy generation market is expected to reach 3.4% by 2013 and 8% by 2018.

Table 1 shows the installed wind power capacity in the world by country or

region. Nearly 50% of wind generation capacities worldwide are installed in

Europe. The countries with the largest installed wind power capacity in Europe

are Germany, Spain and Denmark. In these countries, the main driver of wind

power development has been the so-called fixed feed-in tariffs for wind power.

Such feed-in tariffs are defined by the governments as the power purchase price

that local distribution or transmission companies have to pay for local

renewable power generation that is fed into the network. Fixed feed-in tariffs

reduce the financial risk for wind power investors as the power purchase price is

basically fixed over at least 10 to 15 years.

The USA and Canada host about ¼ the world wind generation capacities, the

major driving forces for further wind energy developments in the USA are:

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