Water Current Turbines

CONTENTS
Foreword iii
Acknowledgements
List of illustrations
CHAPTER 1 INTRODUCTION
1.1 The Objective of this Book 1
1.2 Water Current Turbine (WCT) Technology 2
1.3 Alternative Water-lifting Methods 2
1.4 Background 5
1-5 The S..$;ructure of this Book 5
CHAPTER 2 TECHNICAL ASPECTS
River Currents as an Energy Source 6
Site Selection 12
Measurement of River Current Speed 14
Water Pumping Turbine System Design 14
Turbine Rotor 17
2.5.1 Choice of Turbine Rotor 17
2.5.2 Rotor Construction Materials 25
2.5.3 Rotor Bearings 25
Transmission 2 6
Choice of Pump 30
2.7.1 Pump Types Available 30
2.7.2 Pump Selection for 'Mark I' Machine 35
2-7.3 Pump Selection for 'LOW Cost' Machine 38
Delivery System 38
2.8.1 Pump to River Bank Pipe 40
2.8.2 River Bank to Plants 40
Floats 42
Mooring System 45
Rotor Supporting Frame 45
Rotor Lifting Bechanism 46
Storage Tank Design 46
Installation 48
Operation 5 1
Maintenance 5 2
Conclusions 53
2.17.1 Key Design Features 5 3
2.17.2 Main Technical Features which will
Affect Users 53
2.1 7.3 Further Work
CHAPTER 3 SOCIO-ECONOMIC ANALYSIS (by Peter Burgess)
3.1 Introduction 5 5
3.2 Assessment of the Cost-Effectiveness of Water
Pumping for Irrigation 55
3.2.1 Sensitivity Analysis 6 0
3.2.2 Conclusion GO
3-3 Social Factors 6 1
393.1 Introduction 6 1
3-3.2 Size of Pumping System Relative to 6 2
Size of Landholdings
303.3 Restrictions on Water Output 64
3 . 3 .'4 Social Implications of the Differing
Cost Structures of the Alternative
Pumping Systems 67
3-3.5 The Effects of Constraints on Pump
Siting on Land Values 70
3.3-6 Potential for Local Manufacture 7 1
303.7 Evidence for Potential IJse 7 1
3.308 Comparison with Alternative
Technologies 7 1
3 4 The Relative Cost-Effectiveness of Water
Current Turbines for Irrigation Compared to
Alternative Pumping Methods 72
704.1 Introduction 72
3.4.2 Evidence on Comparative Irrigation
Costs 74
3.5 Conclusion 77
CHAPTER 4 CONCLUSION
Checklist of Key Social, Economic and Technical 8 1
Factors
APPENDICES
APPENDIX 1 : More Detailed Technical Information 85
1.1 Rotor Performance Comparisons 85
1.2 Rotor Bearing Loadings 88
1.3 Calculation of Transmission Ratio 89
1.4 Estimation of System Efficiency 102
1.5 Maintenance Schedule 107
APPENDIX 2 : Case Study of the Economics of Using
Water Current Turbines for Irrigating
Vegetable Gardens in Juba 105