% U+ A+ K, ?4 k# A4 ^Electricity can be generated in many ways. In each case, % q' F) k) |) ya fuel is used to turn a turbine which drives a generator " k$ W$ b8 {/ A! G, s3 z( Bwhich feeds the grid. The turbines are designed to suit the % r3 G: |, |; S- D; I6 F/ ?particular characteristics of the fuel. Wind generated electricity 0 B7 j7 `( V7 t, {+ @1 }( B% G/ H. `0 _is no different. The wind is the fuel – unlike fossil8 ^3 H8 v( s3 a+ P1 I
fuels it is both free and clean, but otherwise it is just the2 I% k5 O; z. b; S/ [6 e' k9 Q9 r
same. It drives the turbine which generates electricity into / t7 h1 I: {) [a grid.9 o% \% r$ s4 P! V: d
The politics and economics of wind energy have played an $ B9 N; m2 E4 D1 o5 R+ vimportant role in the development of the industry and contributed ; k; M4 n# w# C8 Dto its present success. Engineering is, however, * Y: D; `+ w4 |5 M: Q+ B6 ?pivotal. As the wind industry has become better established, ) F7 z6 g; t+ n& i' gthe central place of engineering has become overshadowed- b0 B! t2 x8 J) |) R2 Z9 H
by other issues. This is a tribute to the success1 D: H$ t0 s7 q
of the engineers and their turbines. This volume addresses" n, | a- s A9 P7 E
the key engineering issues: : i( q q9 @0 u1 u+ J7 F• The turbines – their past achievements and future challenges4 |" c3 L4 k4 U; {
– a remarkable tale of technical endeavour and+ m4 q8 ]! p+ ?' a
entrepreneurship.0 t% p# N+ T$ L x0 K
• The wind – its characteristics and reliability – how can8 v. w: i# I# e3 R
it be measured, quantified and harnessed?; [; h/ O3 N, N- \/ r' _! h
• The wind farms – an assembly of individual turbines2 W$ o8 u u% h/ E) n: z7 B3 A
into wind power stations or wind farms – their optimisation/ N0 U9 { ~6 C. E. f7 h3 ]- b
and development.2 e7 F4 t7 w1 C# @
• The grid – transporting the energy from remote locations: L* s& L0 @) F2 p- v- p* j4 C+ S1 T- u
with plentiful wind energy to the loads – the key % t9 F, v% i" xtechnical and strategic challenges. ; \# l% q7 `: HThis volume provides an historical overview of turbine; c! C( U L* B3 f6 k, A' ^# p
development, describes the present status and considers # ^6 g4 \2 T3 ]) V# ofuture challenges. This is a remarkable story starting in 4 {' J3 Z; i; p% S1 ?1 o( U1 k, Lthe nineteenth century and then accelerating through the/ |% K0 I1 N' G: a0 Z
last two decades of the twentieth century on a course very & u% D- L# h$ tsimilar to the early days of aeronautics. The story is far 1 v& t1 {* Z# s) U/ Y6 jfrom finished but it has certainly started with a + o. j- v% `6 u3 F1 a) E3 w6 zvengeance. 8 J, v* z2 F+ V# @Wind must be treated with great respect. The speed of the $ }! c' N; @. Z0 Z& _# n& T$ Twind on a site has a very powerful effect on the economics 9 }! ^- h! Z' Q' tof a wind farm; it provides both the fuel to generate : B" j0 |+ n, }( Uelectricity and the loads to destroy the turbine. This volume% m; {8 i0 C. ]# M
describes how it can be quantified, harnessed and / z( x1 |; Z" \: q) Z+ vput to work in an economic and predictable manner. The " f/ L7 m# z0 ?4 I. B E& L$ Blong-term behaviour of the wind is described as well as its % f- L" F6 k; z, {% u) `9 @9 Qshort-term behaviour. The latter can be successfully forecast 0 b+ r1 p, I+ v; |) zto allow wind energy to participate in electricity markets." C( e0 Q% o. q: c
In order for wind to live up to its raw potential promise, 2 I8 b( V7 Z- @7 v8 Pindividual turbines must be assembled into wind farms or ! d, x/ Q- i8 f& T9 E. D% ^1 Pwind power stations. The design and operation of the different 8 F, p% }" i- C2 g2 Z# _; ytypes of wind farms are discussed and examples6 U% d3 @5 z9 j: Y" u5 s
provided. / P; {2 |; d8 ^8 `; TFinally, the key strategic issue for the future is addressed:7 M& R6 g( @7 r, w
How can the windy parts of Europe, both onshore and offshore, 3 {" I/ f/ R! \& X, hdeliver power for the industrial loads and population : L5 D, [+ _5 O2 Z+ Vcentres. This goal is achieved through the local, + j5 C* \$ X, x5 K& f! |national and international grids. The way in which the grid. c9 J9 k9 D7 X8 J! h/ _/ |8 }
is used and constrained is a key political and technical& a8 l6 S6 h) X0 t) Z* k) l
issue. The technical and regulatory constraints are/ Z+ m- [3 \- ?4 P4 U' p
described and some challenges for the future are raised.$ ]' z2 q. K+ t n+ \
This volume explores how this new, vibrant and rapidly5 \+ D- f1 }7 M$ m: I! @3 ]# M
expanding industry exploits one of nature’s most copious2 i6 h" c: p1 n. x/ r6 G
sources of energy – the wind.; K. b' @! W) R; m' |
( W5 | q( V4 T# G7 {; @ 7 v# z; F# E5 {, d# XINTRODUCTION TO VOLUME 1 32 y. y1 Q3 M! e3 |1 X! G
CHAPTER 1 TURBINE TECHNOLOGY 75 {$ r$ ]) m* P8 h* O6 x- v
1.1 Evolution of Commercial Wind Technology 7" g6 ?* c' U5 ]
1.1.1 Achievements 7* \! ?& r/ Y- _: y7 N% g* ?
1.1.2 The Challenge 8& w- _, v, j a
1.1.3 A Unique Technology 8( f5 {2 y3 h( i
1.1.4 Run up to Commercial Technology 9 ~: g& G3 l$ [4 E( ]1.1.5 Design Styles 105 \7 ]* | f# Q9 v6 o
1.1.6 Design Drivers for Modern Technology 13% a. f, B1 D( b1 W3 z K5 K
1.1.7 Growth of Wind Turbine Size 14 4 n( r# b4 E5 T6 c1.1.8 Architecture of a Modern Wind Turbine 16; E. { x7 @3 J
1.1.9 Erection of Large Wind Turbines 17 6 ]3 ~! K% k9 E8 [7 z T' M/ y1.2 Technology Trends 19. @+ i5 M/ u9 D; [! Y
1.2.1 Larger Diameters 19 4 }, ?8 r) y& L$ u1.2.2 Tip Speed - Offshore and Land Based Designs 203 R4 q" g' E( n! X& ?
1.2.3 Pitch versus Stall 21 # a& K4 o: z* x- k1.2.4 Speed Variation 21 * ^. ~1 L' b. v6 [% m# O1.2.5 Hub Height 22' d0 J, u! q5 ^
1.2.6 Rotor Mass 22 * \" v3 i7 d+ Y( d1.3 Recent Developments 23 6 D, m3 x" `# J2 r9 l1.3.1 Direct Drive Generators 23 & B1 J9 d- k. U2 }1.3.2 Hybrid – Single Stage of Gears and Multi-Pole Generator 25 : A7 `; \6 g) z& o' ?' T1.3.3 Rotor Blade Developments 265 d1 D6 m9 V. y
1.3.4 Single Bearing Arrangement 28 ' K% g4 J' W6 B# l: k2 g1.3.5 Offshore Technology 28* {. L) z3 r; d- @' A# z
1.4 Technology Status 323 w: D% c3 y2 |0 I6 m4 ?5 {
1.4.1 Overall Design Trends 323 c( M5 T7 A6 g8 A- r; S
1.4.2 Size Limitations 33 5 q# A6 g0 j, G) B3 E1.4.3 The Success of Wind Technology 36. ` W1 M0 M* k6 i( d- @* }
1.5 Concluding Remarks and Future R&D 371 T9 V9 M" w* N# R" g$ \" M) N
CHAPTER 2 WIND RESOURCE ESTIMATION 387 U! m& r0 X7 T6 k* N
2.1 Introduction 38) F1 q7 j2 x, H( u1 z
2.2 Regional Wind Resources 384 J1 f" J% ]# m) j9 T( B* D& v/ M
2.3 Wind Atlases 390 E1 E s8 I! l; c% O6 C8 {
2.3.1 Onshore 39 / s4 F* m# w( {- t. _: }2.3.2 Offshore 41 + x7 P2 N2 Q/ X9 O) H2.4 Energy Estimates 410 ~. A( b4 w6 w4 A1 O
2.4.1 Onshore 41 ! X$ D/ ?+ u, N. T8 ~; `2.4.2 Offshore 44* B( Z; [ m" C3 w% s9 @. t
2.4.3 Updating Resource Potential 44 `2 {3 {! Y9 s0 M- q- V% `; U* m2.4.4 Concluding Remarks 459 W# i. M3 ? r1 m) f, l6 H
2.5 Local Wind Resource Assessment and Energy Analysis 45) E# m5 X5 E1 [* B' S& C
2.5.1 Introduction 45 6 z- ?# Q+ c+ D n- j" P# T3 o2.5.2 The Importance of the Wind Resource 479 H- x/ R a- F" _
2.5.3 Best Practice for Accurate Wind Speed Measurements 47" _4 F4 V5 k) h( Z- b0 k
2.5.4 The Annual Variability of Wind Speed 49) N$ m# d3 t' V$ a! A4 ~
2.5.5 Analytical Methods for the Prediction of the Long Term Wind Regime at a Site 53' R! Q [5 F l7 v# r* q
2.5.6 The Prediction of the Energy Production of a Wind Farm 55 A% t2 \4 X5 i+ w8 O3 d# Q8 X2.5.7 Definition of Uncertainty in Predicted Energy Production 572 W8 X/ ]; {- f7 y$ Z
2.6 Offshore Wind Farm Design and Resource Estimation 58- o E p* A, m2 m# s* ?( g
2.6.1 Fundamentals 58 + i' b3 B1 d& ~ q" w6 F2.6.2 Measurement Offshore 59; S' U7 U3 X* A5 H
2.6.3 Wind Analysis Offshore 59% Q+ \; C: C5 m9 W! K- j o* W
2.6.4 Energy Prediction 59# Y. \. `2 r. o" A1 C/ N
2.6.5 Other Effects to Consider Offshore 592 L2 P! g1 H9 e/ r0 X$ g$ R+ H! U
2.7 Forecasting 60 & t3 ~5 k: c6 e0 T2.7.1 Overview of the Method 61 0 q# e, J, X( W2.7.2 Improvement over Persistence 62 , N. O9 o9 F, T% w& z2.7.3 Power Output 620 M% s5 d' i! e* |- [ H( n. F
2.7.4 Portfolio Effects 63' i4 E- x- p* b( h, X' S+ O8 N. |
2.7.5 Conclusions 637 F2 v8 c3 n7 L
2.8 Future Developments 63( F, p/ N2 a. y7 H
CHAPTER 3 WIND FARM DESIGN 650 ]2 i# i7 e! a
3.1 Introduction 658 W, R5 K$ _! E& w: ]
3.2 Preliminary Layout Design 65* y# {" i& u! k1 e! A
3.3 Detailed Layout Design 65: ^& Q# U, W4 H( h; n: I1 b% ]
3.4 The Infrastructure 66* ?9 A# Q% g2 x2 }
3.4.1. Civil Works 66* Z X: n' q N" X6 B
3.4.2. Electrical Works 67* s' j* p J6 Q" ]' r0 @
3.4.3. SCADA and Instruments 67 / T7 @8 o& p6 R& D, T% l; N3 n) u3.5 Construction 67 6 i1 y, }- ?+ E% D( q+ Q8 ~5 `! @3.6 Costs 68 + m. F% ^6 J/ D: h' ~+ Z3 D, |' f3.7 Commissioning and Operation 688 T" H* r( K8 g% o! W
3.8 Concluding Remarks 69 ! c3 D* Y1 n. A9 H0 KCHAPTER 4 TRANSMISSION AND DISTRIBUTION NETWORKS 70! @/ d- E% G2 y, b8 i" _" Z
4.1 Introduction 70 $ [5 h9 |. D6 o* C8 v' [8 r4.2 Setting the Scene 700 B2 U! r- N# | P: i; Y _+ x+ I
4.2.1 Large Interconnected Networks 700 {. u I" u7 m0 I7 j( E$ r7 D
4.2.2 Small Isolated Networks 71 & _9 b. D4 Y: K9 Q6 b" I4.3 Electricity Networks 72 7 Y4 z( X3 t: K4.4 Considerations for Wind Energy 74! Y9 j2 r: D8 W' L
4.4.1 Connections 74 l. }, G# @# K
4.4.2 Operation 75 3 D& G: O$ m: |4.4.3 Strategic Planning Considerations 77- a! z4 V1 |2 g) d% r
4.5 Issues for High Wind Penetration in Europe 80 2 u& Y8 X+ T7 R& Q8 ?: G4.6 Concluding Remarks 82 ; _! }$ |- i2 s+ W8 m: gCHAPTER 5 RESEARCH AND DEVELOPMENT 84 6 Z5 h; U5 n3 `5 ?5 A5.1 Wind Industry Research and Development Overview 84$ q. |0 W$ N2 t
5.2 Socio-Economic, Policy and Market Issues 85 8 i% n4 w& H2 v/ M5.2.1 Transparency 85 5 ?2 h( x" C4 g3 R# v. F5.2.2 Increasing the Value of Wind Power 863 T8 E% Q0 o5 d8 G
5.2.3 Education and Human Resources Development 86 : H! p1 X' v2 T! M$ ^3 P6 }5.3 Environmental and Social Impacts 86) s; B$ K6 ?% S! {1 m+ |- ?
5.4 Turbine and Component Design Issues 871 v/ |/ |7 C# z1 t/ ~" U! N
5.5 Testing, Standardisation, Certification and Safety 88. y: B* @1 S+ x; B9 W) K
5.6 Grid Integration, Energy Systems, and Resource Prediction 88# C3 M: j5 F" r0 F
5.7 Operation and Maintenance 897 v9 z, r4 v, ^9 h; I" D& d
5.8 Location of Wind Farms 90 8 a) U. B. z0 ?$ j0 D0 ~. I7 V* s+ M' q5.9 Offshore Wind 905 D) P. O% X b g" l
5.10 Multi-Megawatt Turbines 91 % a4 `$ d6 K7 m* b! a5.11 Summary of R&D Objectives 91