Small Hydroelectric Engineering Practice

256 Pages·2014·36.78 MB·English

by  Bryan Leyland

Small hydroelectric engineering practice

Small hydroelectric engineering
practice
Bryan Leyland
Leyland Consultants, Auckland,New Zealand
ThisbookcontainsaCD-ROMwhichincludesspreadsheetprograms,drawings,designdetailsand
specifications.ThecontentoftheCDcanbedownloadedathttp://www.crcpress.com/9781138000988
Covercredits:
Frontcover:
CoandaintakephotographprovidedbyDulasLtd,UK
PhotographofPaeraupowerhouseandturbinetakenbyBryanLeylandwith
permissionfromTrustPower,Tauranga,NewZealand
Backcover:
PhotographofPaeraupowerhouseandcanalandthepenstocklinetakenby
BryanLeylandwithpermissionfromTrustPower,Tauranga,NewZealand

CRCPress/BalkemaisanimprintoftheTaylor&FrancisGroup,aninformabusiness
©2014Taylor&FrancisGroup,London,UK
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Allrightsreserved.Nopartofthispublicationortheinformationcontained
hereinmaybereproduced,storedinaretrievalsystem,ortransmittedinany
formorbyanymeans,electronic,mechanical,byphotocopying,recordingor
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Althoughallcareistakentoensureintegrityandthequalityofthispublication
andtheinformationherein,noresponsibilityisassumedbythepublishersnor
theauthorforanydamagetothepropertyorpersonsasaresultofoperation
oruseofthispublicationand/ortheinformationcontainedherein.
LibraryofCongressCataloging-in-PublicationData
Leyland,Bryan.
Smallhydroelectricengineeringpractice/BryanLeyland,MSc
LeylandConsultants,Auckland,NewZealand.
pagescm
Includesbibliographicalreferencesandindex.
ISBN978-1-138-00098-8
1. Smallscalehydropower. I.Title.
TK1081.L475 2014
621.31’2134—dc23
2013042304
Publishedby: CRCPress/Balkema
P.O.Box11320,2301EHLeiden,TheNetherlands
e-mail:[email protected]
www.crcpress.com–www.taylorandfrancis.com
ISBN:978-1-138-00098-8(Hardback)
ISBN:978-1-315-81653-1(eBookPDF)
This book is dedicated to my wife Jane;without her active support
throughout my career and while I was writing this book,
it would never have been written.

Contents
Preface xiii
Acknowledgements xv

Abouttheauthor xvii
Listoffigures xix
Listofabbreviations xxiii
1 Introduction 1
1.1 Keyfeaturesofsmallhydroschemes 3
2 Schemeidentification 5
2.1 Preliminarystudy 5
2.1.1 Costestimates 6
2.2 Feasibilitystudy 6
2.2.1 Sitesurvey 6
2.2.2 Hydrology 7
2.2.3 Geology 8
2.2.4 Environmentalassessment 8
2.2.5 Preliminaryestimates 9
2.2.6 Preliminaryreport 10
3 Refiningthedesign 11
3.1 Hydrology 11
3.2 Geology 12
3.3 Headworks 12
3.3.1 Spillwayoptions 13
3.3.2 Intakes 13
3.3.3 Canaldesign 14
3.4 Penstocksandintakes 16
3.4.1 Penstockintakes 16
3.4.2 Steelpenstocks 16
3.4.3 Woodstavepenstocks 16
3.4.4 PlasticandGRPpenstocks 17
3.5 Turbineselection 17
3.5.1 Lowheadturbines 17
3.5.2 Mediumheadturbines 19
3.5.3 Highheadturbines 19
3.6 Powerhousearrangement 20
viii Contents
3.7 Usefulspreadsheets 20
3.8 Preliminaryfinancialanalysis 21
3.9 Outsidefinancing 21
3.9.1 “Bankable’’feasibilitystudy 22
3.9.2 Economicandfinancialanalysis 22
4 Detaileddesignofintakeworks,canalsandpenstocks 25
4.1 Environmentalfactors 25
4.2 Finaloptimisation 27
4.2.1 Technicaloptimisation 28
4.2.2 “Alab’’computerprogram 28
4.2.3 “Hydrohelp’’computerprogram 29
4.3 Intakesatlowweirs 29
4.3.1 Coandascreen 29
4.3.2 Streambedintake 32
4.3.3 Bypassing 32
4.3.4 Settlingbasin 33
4.4 Conventionalintakes 35
4.4.1 Screencleaners 37
4.4.2 Intakegates 38
4.4.3 Penstockfilling 42
4.4.4 Additionalinformationonintakes 43
4.5 Spillways 44
4.5.1 Flap(fishbelly)gates 44
4.5.2 Obermeyergates 45
4.5.3 Radialgates 46
4.6 Bypassgates 52
4.7 Stoplogsandbulkheads 53
4.8 Canalregulatinggates 54
4.9 Additionalinformationongates 56
4.10 Canals 56
4.10.1 Controllingleakage 58
4.10.2 Smallunlinedcanals 58
4.10.3 Canallinings 58
4.10.4 Underdrainage 59
4.10.5 Furtherinformation 59
4.11 Penstocksandwaterhammer 59
4.11.1 Waterhammer 60
4.11.2 Steelpenstocks 62
4.11.3 Glassreinforcedplastic(GRP)penstocks 68
4.11.4 HDPEandPVCpenstocks 71
4.12 Surfacetreatmentandpaintingofsteelwork 72
5 Turbineselection 73
5.1 Introduction 73
5.2 Numberofturbines 73
5.3 Particulateerosion 74
Contents ix
5.4 KaplanandFrancisturbines 75
5.4.1 Guidevanes 78
5.4.2 Guidevaneactuation 81
5.4.3 Cavitation 83
5.4.4 Hydraulicstabilityandroughrunning 86
5.5 Lowheadturbines 87
5.5.1 DimensionsofKaplanturbines 88
5.5.2 VerticalKaplanturbines 88
5.5.3 Bulbturbines 91
5.5.4 Pitturbines 92
5.5.5 Matrixturbines 93
5.5.6 AxialKaplanturbines 95
5.5.7 OpenflumeKaplanturbines 95
5.5.8 Verylowheadturbines 98
5.5.9 Stoplogsandemergencyisolation 98
5.6 Mediumheadturbines 98
5.6.1 DimensionsofFrancisturbines 99
5.6.2 Airadmission 102
5.6.3 VerticalFrancisturbines 103
5.6.4 HorizontalFrancisturbines 104
5.6.5 TwinhorizontalFrancisturbines 107
5.6.6 Inletvalves 111
5.6.7 Reliefvalves 113
5.6.8 Bypassvalves 114
5.7 Peltonturbines 115
5.7.1 DimensionsofPeltonturbines 115
5.7.2 Peltonturbinearrangement 115
5.7.3 Peltonturbinerunners 117
5.7.4 Peltonturbineoptions 119
5.7.5 Turgoturbines 121
5.8 Governingsystems 121
6 Generators 125
6.1 Overspeed 125
6.2 Synchronousgenerators 126
6.2.1 Stators 127
6.2.2 Corona 129
6.2.3 Excitationsystems 129
6.2.4 Neutralearthing 130
6.2.5 Lightningprotection 131
6.2.6 Generatorcooling 132
6.2.7 Overspeedtesting 135
6.2.8 Increasinggeneratorinertia 136
6.2.9 Bearings 136
6.2.10 PTFEbearings 138
6.2.11 Bearingcoolingandmonitoring 138
6.2.12 Inductiongenerators 139