$ P1 U. x" O4 M k. J6 P 0 x/ ?- B' [( F+ h. a3 qElectricity can be generated in many ways. In each case, 9 x ~) v+ J8 b& S9 l. Ua fuel is used to turn a turbine which drives a generator & E( [- h# R* t7 M Cwhich feeds the grid. The turbines are designed to suit the) @. n8 K# n7 h2 b
particular characteristics of the fuel. Wind generated electricity 6 Q% p6 B4 d ]+ ]& [1 F& zis no different. The wind is the fuel – unlike fossil ; S2 Y! l# x) ^3 N. C5 afuels it is both free and clean, but otherwise it is just the , F, K# _# S+ ^, [' `1 m- ^same. It drives the turbine which generates electricity into8 V; Z: j0 v- ~/ L- M$ P
a grid., N2 w6 `; \0 |; w1 Y/ U4 V4 F* p& ^
The politics and economics of wind energy have played an3 K3 S6 V Y1 ~9 i" s. Y0 h) p7 y
important role in the development of the industry and contributed+ P- P1 m) q8 h" S
to its present success. Engineering is, however,5 @# J) Y( K/ B+ n
pivotal. As the wind industry has become better established,8 t9 P% k& E) ]* A+ B j
the central place of engineering has become overshadowed & b, G& r0 e1 S' }by other issues. This is a tribute to the success + A0 M7 o7 H8 E- _% J6 L* Jof the engineers and their turbines. This volume addresses) B+ _6 Y( g6 x* R3 k1 ]- [
the key engineering issues: 9 F1 ]: `; s9 c6 t• The turbines – their past achievements and future challenges % }- t3 ^' T9 L, H– a remarkable tale of technical endeavour and: t. Y" U: S5 Y0 {
entrepreneurship.; O* B: \, V" Y. M s* u3 T
• The wind – its characteristics and reliability – how can * z+ p3 `& i% G, kit be measured, quantified and harnessed?3 Y4 \: X9 J, I% k7 Z+ C$ F7 m: l3 M
• The wind farms – an assembly of individual turbines ' q3 ^, ?; O9 Z9 ] ~# C: `into wind power stations or wind farms – their optimisation $ `; |9 D: x( C+ p& h8 V, Rand development.; R# u: D) e( K9 l1 S! C
• The grid – transporting the energy from remote locations7 B% B3 y6 c/ m9 Q* }, a% i
with plentiful wind energy to the loads – the key 2 L+ ?& Z& T' V9 [, N! rtechnical and strategic challenges. 7 K6 p- E/ B" C5 eThis volume provides an historical overview of turbine ; h: [% i; H, j% ~. i1 A+ b* [4 fdevelopment, describes the present status and considers 8 U- \4 C0 g( I+ \1 _0 ]$ F' Cfuture challenges. This is a remarkable story starting in+ a2 S$ L @$ h+ ^" {- I
the nineteenth century and then accelerating through the" F/ p0 f9 u! P- o. y6 J% @1 m3 Z7 Z1 C
last two decades of the twentieth century on a course very- z1 \$ f$ l8 Y+ H& }* k, f1 M, v
similar to the early days of aeronautics. The story is far 4 y: c( T% T6 Q7 B+ gfrom finished but it has certainly started with a 6 N S: b% D1 x7 v: G! B/ |& Qvengeance. , V2 `9 t1 i& Y2 d; M- \Wind must be treated with great respect. The speed of the 5 R" A; U1 V( Q, P8 }wind on a site has a very powerful effect on the economics 1 R) b2 o% t# o" i$ J# mof a wind farm; it provides both the fuel to generate u3 I# w& f) i3 V
electricity and the loads to destroy the turbine. This volume 5 G9 r1 @2 l2 z5 |describes how it can be quantified, harnessed and& K" c% U" r, N, d0 v: D _
put to work in an economic and predictable manner. The ' R; F- g0 ?! @+ V1 tlong-term behaviour of the wind is described as well as its * |$ l) {6 `* V: U$ `3 h O4 ]+ ushort-term behaviour. The latter can be successfully forecast 0 B* M: f9 H8 J# ^9 t. Pto allow wind energy to participate in electricity markets.! P3 F1 }' p6 s2 o2 f9 q, O/ D
In order for wind to live up to its raw potential promise, J) m# s! r, |' U k$ J' tindividual turbines must be assembled into wind farms or1 v2 f" a$ a( K' x
wind power stations. The design and operation of the different % H+ Y3 A! Z* s S) J' otypes of wind farms are discussed and examples. `" q( e P1 S* |' d5 x* z- g
provided. - ]% Q/ _; F$ q. n8 \$ T" y5 }8 tFinally, the key strategic issue for the future is addressed:- B- d) H3 S$ r' F
How can the windy parts of Europe, both onshore and offshore,9 y$ R6 F: O% f- L4 \
deliver power for the industrial loads and population: C6 d h A% d% w0 {" `4 W' d
centres. This goal is achieved through the local,$ Y) Q( ?* s5 N
national and international grids. The way in which the grid* s+ y' Q, d* v" T
is used and constrained is a key political and technical1 H5 Q# A2 B. m4 ?5 X$ D; C
issue. The technical and regulatory constraints are2 C/ j, G: W" x6 R* u
described and some challenges for the future are raised. * v* O0 V" B% {/ U3 b$ \This volume explores how this new, vibrant and rapidly & i' ?0 q2 j) T$ uexpanding industry exploits one of nature’s most copious5 \! S5 l% q4 v( H
sources of energy – the wind.5 j ^/ H X: w; e( j* X
- g' J0 @% M; L! d, e& E$ G6 h& R1 v" r, S9 i8 i
INTRODUCTION TO VOLUME 1 3 2 Q+ M) U( M {5 uCHAPTER 1 TURBINE TECHNOLOGY 7 " r, [& r% J0 ?) A' {1.1 Evolution of Commercial Wind Technology 7: i* |& X# M0 X& U
1.1.1 Achievements 7 2 w* V0 s( K S' u8 W8 Y1.1.2 The Challenge 89 D( G+ D2 Y: g7 Z$ _: K! C$ t
1.1.3 A Unique Technology 81 ]8 C/ v7 e3 Z. f8 u7 D8 B. Y# o
1.1.4 Run up to Commercial Technology 9 $ q' X7 [* A5 |0 i4 J. A2 N; b1 {1.1.5 Design Styles 10 : l5 ]& q1 [( j; o) Q1.1.6 Design Drivers for Modern Technology 130 c; ?, Q. R: }$ P* |+ N; Y6 J
1.1.7 Growth of Wind Turbine Size 14 3 r; u5 O! p: A" k* ~0 Z1.1.8 Architecture of a Modern Wind Turbine 16 # B$ Q# p: W; l; E; v1.1.9 Erection of Large Wind Turbines 17; i/ d# f2 a/ t }# e7 z
1.2 Technology Trends 19& i8 i/ H r% V# Y* y% j
1.2.1 Larger Diameters 19 5 D8 i4 T6 J1 G1.2.2 Tip Speed - Offshore and Land Based Designs 20 / Z+ z' Y6 Z+ c" p' g* `1.2.3 Pitch versus Stall 21 2 ?1 L8 i- ^1 |, a: |1.2.4 Speed Variation 21: y/ a% t$ |% E+ b1 A# H% e+ Z
1.2.5 Hub Height 22) s( N/ |) _2 O$ @
1.2.6 Rotor Mass 22; _3 V1 `, E" \4 o6 C* J
1.3 Recent Developments 231 i' C$ H) ]% G4 s. A
1.3.1 Direct Drive Generators 23 # m5 o# q7 D4 @1.3.2 Hybrid – Single Stage of Gears and Multi-Pole Generator 25; }" l% T# K$ G( G! N5 o( E4 k, I
1.3.3 Rotor Blade Developments 26 ) ]& ~& p7 [8 e( q0 u+ d1.3.4 Single Bearing Arrangement 28 ) g) u$ |$ a, n7 G/ ^4 f! b1.3.5 Offshore Technology 28! z6 H2 t7 ], i1 y0 d4 u0 P
1.4 Technology Status 32; I" G2 H% f4 y: {2 }4 W
1.4.1 Overall Design Trends 326 c1 A; _- N% X- a. n
1.4.2 Size Limitations 33! N' f! P, V7 \4 r5 h% l4 a
1.4.3 The Success of Wind Technology 363 b9 D/ I8 Y6 E2 o v5 l
1.5 Concluding Remarks and Future R&D 370 \2 F! e1 U% X5 k( j
CHAPTER 2 WIND RESOURCE ESTIMATION 38 " r# G# {+ |- a$ E( e2.1 Introduction 38 * a2 X! Z2 H+ W1 O4 u( f4 r2.2 Regional Wind Resources 38 1 V5 D8 q. _7 r, \2.3 Wind Atlases 39 4 Z$ I$ X1 A8 q* c2.3.1 Onshore 39 + W1 H; H. i0 \2.3.2 Offshore 41) e5 e, d# L! z
2.4 Energy Estimates 41/ w3 X) j. F# e1 ]1 K- C$ _
2.4.1 Onshore 418 i- V7 h' J* E+ g% v4 O. E7 F$ M4 f
2.4.2 Offshore 443 H" j0 y% d# t: q9 k
2.4.3 Updating Resource Potential 44. ]2 h2 x7 R' c; b( R* q5 }3 M* z
2.4.4 Concluding Remarks 45 ! W2 ~( [6 v- r0 f2.5 Local Wind Resource Assessment and Energy Analysis 45 * h. f! |4 f: y% P3 \2.5.1 Introduction 45! @4 Z/ B9 x# f% U
2.5.2 The Importance of the Wind Resource 47 ; J. ~- n s& {% |2.5.3 Best Practice for Accurate Wind Speed Measurements 474 k5 R/ X+ M9 z4 M
2.5.4 The Annual Variability of Wind Speed 49' |; s/ x( T; j; Q. z3 F! M
2.5.5 Analytical Methods for the Prediction of the Long Term Wind Regime at a Site 533 \0 D! L/ ?1 u
2.5.6 The Prediction of the Energy Production of a Wind Farm 55 # s/ q/ m0 N! j% g, e& n7 q2.5.7 Definition of Uncertainty in Predicted Energy Production 57 ! X- _/ C: A* Z9 R2.6 Offshore Wind Farm Design and Resource Estimation 58+ P4 \& Q! T8 v: ]$ U% o: Y s& r5 ]
2.6.1 Fundamentals 58( x$ q( |! }; u! A: v1 j
2.6.2 Measurement Offshore 59) S- `3 G% ?5 d0 X2 q+ i$ M
2.6.3 Wind Analysis Offshore 59 # W. z; m- p) {( O6 p) L4 i2.6.4 Energy Prediction 59 / `' v3 {2 t6 i* J1 ~- L; V2 n/ c2.6.5 Other Effects to Consider Offshore 59 / t- f" A+ w3 @+ l& d5 M2.7 Forecasting 605 p' {8 u" I6 e8 J2 \3 C" m( I( O
2.7.1 Overview of the Method 61% t: O- @! z6 ?' U- g6 g( w9 a e: n
2.7.2 Improvement over Persistence 62( n( ?5 r; e7 L% I$ m4 H
2.7.3 Power Output 62 ' b) q7 b4 y# e/ K: b2.7.4 Portfolio Effects 636 |% _; B: ~% G* U! g
2.7.5 Conclusions 63 4 B8 s' M! f$ y m$ q8 }2.8 Future Developments 63) s% r9 q# S j( p
CHAPTER 3 WIND FARM DESIGN 65/ M6 o" I1 |# `5 J$ E) g @1 c( R
3.1 Introduction 65 * @+ u+ C7 w4 j9 }3.2 Preliminary Layout Design 65 ( v, Y2 Z' N8 ^/ a5 B3.3 Detailed Layout Design 659 Z" e z; E) {; V5 N
3.4 The Infrastructure 66- R p, t; ^. C0 ^- o
3.4.1. Civil Works 66; ^4 @* x" o, `5 G4 A
3.4.2. Electrical Works 676 `5 ^8 B- G: G- w& w
3.4.3. SCADA and Instruments 67 x9 B r+ I5 ` R# J
3.5 Construction 67 6 u+ H" i+ K5 ~( c" u7 F3.6 Costs 68 7 s5 a/ k6 m e3.7 Commissioning and Operation 68 : `) e' q8 s" v/ s) ?3.8 Concluding Remarks 69 8 t8 F7 ?$ {7 R: }; P; O. D8 ^CHAPTER 4 TRANSMISSION AND DISTRIBUTION NETWORKS 70 4 C* e7 {( }. u! ?3 n2 Q4.1 Introduction 70 0 P9 L3 j* a8 i3 [+ g4.2 Setting the Scene 702 ?6 J. w+ s. z8 Q$ u! v, G; B4 c
4.2.1 Large Interconnected Networks 709 e& Z X+ S" o- t+ C; e6 J+ ~
4.2.2 Small Isolated Networks 71" Y1 c, ]3 G3 _. j3 j9 J
4.3 Electricity Networks 72 * v: N( I- _: w) _3 h7 [" F5 z ^$ Z4.4 Considerations for Wind Energy 74* c3 ?* c0 d) f* e
4.4.1 Connections 74 ; `8 d; ?/ M' u, z4.4.2 Operation 75 2 k2 x6 D3 w1 I4.4.3 Strategic Planning Considerations 77% i/ ?1 M; O' F- d+ b: U* K
4.5 Issues for High Wind Penetration in Europe 803 U8 j1 `3 j$ ]
4.6 Concluding Remarks 82+ K- k; q5 Z+ W v4 v/ v$ O
CHAPTER 5 RESEARCH AND DEVELOPMENT 849 m7 @: K8 @# n: J, ]$ j
5.1 Wind Industry Research and Development Overview 84 $ p7 _: E; B0 ]7 c+ {% F) K5.2 Socio-Economic, Policy and Market Issues 85. B" c( R3 W u$ z- N8 |
5.2.1 Transparency 85 % j7 ^( ]6 y+ A5.2.2 Increasing the Value of Wind Power 86 . ~: H) ?- J- e6 @) ^5.2.3 Education and Human Resources Development 86& h! s! Z0 ~2 J5 s
5.3 Environmental and Social Impacts 864 D% q7 u# G6 f
5.4 Turbine and Component Design Issues 87 ' w8 c. \# V+ P9 c& ], ?( g5.5 Testing, Standardisation, Certification and Safety 884 f0 n' w( N' Z! {0 b6 a
5.6 Grid Integration, Energy Systems, and Resource Prediction 887 U+ N) F, T3 H" \( l
5.7 Operation and Maintenance 89! X1 {3 C2 J5 N9 u6 I# v
5.8 Location of Wind Farms 90( Q8 Y- e. D4 A# {+ y, u2 }3 i, {* g
5.9 Offshore Wind 90+ O0 n+ w6 @1 E5 }) f% O. d
5.10 Multi-Megawatt Turbines 91 & y, A( c: t8 y2 g/ N+ K; W9 K5.11 Summary of R&D Objectives 91