IWA INTERNATIONAL 33-3 WORKSHOP AGREEMENT First edition 2021-03 Technical guidelines for the development of small hydropower plants - Part 3: Design principles and requirements Reference number IWA33-3:2021(E) ISO @ ISO 2021 IWA33-3:2021(E) COPYRIGHTPROTECTEDDOCUMENT IS02021 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may below or ISo's member body in the country of the requester. ISO copyright office CP 40i : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +41 22.749 01 11 Email: copyright@iso.org Website: www.iso.org Published in Switzerland ii IS02021-Allrights reserved IWA33-3:2021(E) Contents Page Foreword vi Introduction vii 1 Scope. .1 2 Normativereferences .1 3 Terms and definitions .1 4 Hydrology. 1 4.1 Basic data 1 4.2 Runoff (discharge) 2 4.3 Flood. 3 4.4 Stage-discharge relation curve 4 4.5 Sediment,evaporation,ice regime and others 5 4.6 Rationalitycheck of theoutcomes 5 5 Engineering geology .6 5.1 General provisions 6 5.2 Regional geology. 7 5.3 Engineering geology of thereservoir area 7 5.4 Engineering geology of hydraulic structures 8 5.5 Naturalconstructionmaterial 10 6 Hydraulic engineering and energy calculation 11 6.1 General provisions 11 6.2 Computation of runoffregulation .11 6.3 Hydraulic energy calculation .12 6.4 .13 Loadforecastandelectricpowerandenergybalance 6.5 Selectionofflood regulationand characteristicflood-control level 13 6.6 Selection of normal waterlevel and dead storage waterlevel. 13 6.7 Selectionof installed capacityandtypeofunit 14 6.8 Selection of dimensions of headrace andvolume of daily regulationpool. 14 6.9 Analysis of thereservoirsedimentdepositionand calculation ofthebackwater .14 6.10 Reservoir operationmodeand operational characteristics. ..15 Engineering layout and hydraulic structure. .15 .15 7.1 General provisions 7.2 General engineering layout. 16 7.3 Water retaining structure. 18 7.4 Water release structure 20 7.5 Water diversion structure .23 7.6 Powerhouse structure. 26 7.7 Engineering safety monitoring 31 7.8 Concrete strength and durability 32 Hydraulic machinery, fire protection, heating and ventilation 8 .33 8.1 General requirements for selection of turbine and generator .33 8.2 .34 Selectionofturbineratedhead 8.3 Selection of turbine type. 35 8.4 Selection ofbasicparameters ofthereactionturbine 36 8.5 Selection ofbasicparameters oftheimpulseturbine 38 8.6 Unit transient performance analysis. 39 8.7 Turbine governing system... 40 8.8 Turbine main inlet valve. 40 8.9 Cooling water and drainage system 41 8.10 Oil system 42 8.11 Compressedair system .42 8.12 Hydraulic monitoring system 43 @ IS0 2021 - All rights reserved iii