IWA 33-1:2019

Technical guidelines for the development of small hydropower plants — Part 1: Vocabulary

This document defines the professional technical terms and definitions commonly used for small hydropower (SHP) plants.

Lignes directrices techniques pour le développement de la petite hydraulique — Partie 1: Titre manque

General Information

• Status: Published
• Publication Date: 09-Dec-2019
• ICS: 27.140 - Hydraulic energy engineering
• Technical Committee: ISO/TMBG - Technical Management Board - groups
• Drafting Committee: ISO/TMBG - Technical Management Board - groups
• Current Stage: 6060 - International Standard published
• Start Date: 10-Dec-2019
• Completion Date: 10-Dec-2019

Standards Content (Sample)

INTERNATIONAL IWA
WORKSHOP 33-1
AGREEMENT
First edition
2019-12
Technical guidelines for the
development of small hydropower
plants —
Part 1:
Vocabulary
Reference number
IWA 33-1:2019(E)
©
ISO 2019

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IWA 33-1:2019(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
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Published in Switzerland
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IWA 33-1:2019(E)

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Terms related to hydrology . 1
4.1 Hydrological observation . 1
4.2 Hydrologic data processing . 3
4.3 Hydrological computation . 3
5 Terms related to engineering geology . 5
6 Terms related to hydraulic engineering and energy . 6
7 Terms related to hydraulic structure . 8
7.1 Structure type . 8
7.2 Dam . 9
7.3 Water gate/sluice .10
7.4 Spillway .10
7.5 Power house .12
7.6 Forebay and penstock .13
7.7 Surge chamber .14
7.8 Tailrace structures .15
7.9 Tunnel, culvert and culvert pipe .15
7.10 Intake .16
7.11 Sediment management facility .16
8 Terms related to engineering construction .17
8.1 Diversion .17
8.2 Closure .17
8.3 Cofferdam .18
8.4 Pit drainage .18
9 Terms related to hydraulic machinery .19
9.1 Hydraulic turbines .19
9.1.1 Types of hydraulic turbine .19
9.1.2 Turbine parameters and turbine characteristics .22
9.2 Hydro turbine generator .25
9.2.1 Types of hydro turbine generator .25
9.2.2 Parameters of a hydro turbine generator .25
9.3 Hydro turbine governing system .26
9.4 Oil, compressed air and cooling water supply systems .26
9.4.1 Oil system .26
9.4.2 Compressed air system .27
9.4.3 Water supplying and discharging system.27
9.5 Valve .28
9.6 Installation and testing of turbine generator units .29
10 Terms related to hydro mechanical structure .30
10.1 Gate .30
10.2 Trash rack and trash-removal device .31
10.3 Hoist and crane .32
11 Terms related to electrical system .32
11.1 System operation mode .32
11.2 Main electrical connection .33
11.3 Transformer.34
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IWA 33-1:2019(E)

11.4 Switchgear installation .35
11.4.1 Switching device . . .35
11.4.2 Transformers for measurement and protection .36
11.4.3 Bus and cable .36
11.5 Excitation system .37
11.6 Supervisory control and protection system .38
11.6.1 Supervisory and control system .38
11.6.2 Relay protection .42
11.6.3 Synchronizing system .42
11.7 Lightning protection and grounding .43
11.8 Plant service power and near region and construction power supply .44
11.9 Direct-current system .45
11.10 Communication .45
12 Terms related to social and environmental impact assessment .46
13 Terms related to economic evaluation and project investment .47
Annex A (informative) Workshop contributors .49
Bibliography .51
Alphabetical index of terms .52
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Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
International Workshop Agreement IWA 33 was approved at a workshop hosted by the Standardization
Administration of China (SAC) and Austrian Standards International (ASI), in association with the
International Center on Small Hydro Power (ICSHP), held in Hangzhou, China, in June, 2019.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
A list of all parts in the IWA 33 series can be found on the ISO website.
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Introduction
Small hydropower (SHP) is increasingly recognized as an important renewable energy solution to
the challenge of electrifying remote rural areas. However, while most countries in Europe, in North
and South America and in China have high degrees of installed capacity, the potential of SHP in many
developing countries remains untapped and is hindered by a number of factors including the lack of
globally agreed good practices or standards for SHP development.
The technical guidelines for the development of small hydropower plants contained in this document
address the current limitations of the regulations applied to technical guidelines for SHP plants by
applying the expertise and best practices that exist across the globe. It is intended for countries to
utilize this document to support their current policy, technology and ecosystems. Countries that have
limited institutional and technical capacities will be able to enhance their knowledge base in developing
SHP plants, thereby attracting more investment in SHP projects, encouraging favourable policies and
subsequently assisting in economic development at a national level. This document will be valuable for
all countries, but especially allow for the sharing of experience and best practices between countries
that have limited technical know-how.
This document is the result of a collaborative effort between the United Nations Industrial Development
Organization (UNIDO) and the International Network on Small Hydro Power (INSHP). About 80
international experts and 40 international agencies were involved in this document’s preparation
and peer review. This document can be used as the principles and basis for the planning, design,
construction and management of SHP plants up to 30 MW.
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International Workshop Agreement IWA 33-1:2019(E)
Technical guidelines for the development of small
hydropower plants —
Part 1:
Vocabulary
1 Scope
This document defines the professional technical terms and definitions commonly used for small
hydropower (SHP) plants.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
4 Terms related to hydrology
4.1 Hydrological observation
4.1.1
precipitation
liquid or solid products of the condensation or sublimation of water vapour falling from clouds or
deposited from air on to the ground
Note 1 to entry: It is the amount of precipitation on a unit of horizontal surface per unit time.
[SOURCE: UNESCO/WMO, WMO-No. 385, Section 2 No. 1114]
4.1.2
precipitation days
number of days with daily precipitation more than 0,1 mm within a specified period of time
4.1.3
precipitation duration
period of time during which continuous precipitation occurs at a specific point or within a specific area
[SOURCE: UNESCO/WMO, WMO-No. 385, Section 2 No. 1115]
4.1.4
precipitation intensity
rainfall intensity
rate at which precipitation occurs, expressed in units of depth per unit of time
[SOURCE: UNESCO/WMO, WMO-No. 385, Section 2 No. 1157]
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4.1.5
effective rainfall
part of the rainfall which contributes to runoff
Note 1 to entry: In groundwater, it is the part of the rainfall which contributes to groundwater recharge.
Note 2 to entry: In agriculture, it is that part of the rainfall which remains in the soil and contributes to the
growth of crops.
[SOURCE: UNESCO/WMO, WMO-No. 385, Section 2 No. 458]
4.1.6
probable maximum precipitation
PMP
maximum rainfall that can occur under modern climate conditions within a given period of time in a
certain river basin area
4.1.7
evaporation
water volume of extracting moisture by converting liquid into vapour through heat conduction within
a certain period of time
Note 1 to entry: It is often expressed in terms of the depth of water layer evaporated.
4.1.8
infiltration
percolation
seepage
flow of water through the soil surface into a porous medium
[SOURCE: UNESCO/WMO, WMO-No. 385, Section 2 No. 795]
4.1.9
infiltration intensity
speed at which water will enter a given soil at any given time
4.1.10
stage
water level
elevation of the free water surface of a water body relative to a specified datum
[SOURCE: UNESCO/WMO, WMO-No. 385, Section 2 No. 1621]
4.1.11
maximum stage
maximum instantaneous stage at a certain observation point within the specified duration
4.1.12
minimum stage
minimum instantaneous stage at a certain observation point within the specified duration
4.1.13
discharge
rate of flow
volume of water flowing through a river (or channel) cross section per unit time
[SOURCE: UNESCO/WMO, WMO-No. 385, Section 2 No. 391]
4.1.14
maximum discharge
maximum instantaneous fluid volume which passes through a certain cross section within a specified
duration
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4.1.15
minimum discharge
minimum instantaneous fluid volume which passes through a certain cross section within a specified
duration
4.1.16
mean discharge
averaged flow which passes through a certain cross section within a specified duration
EXAMPLE Daily, monthly or yearly mean flow.
4.2 Hydrologic data processing
4.2.1
isohyetal map
map showing the rainfall distribution by a contour connecting the points of equal rainfall
4.2.2
runoff isopleth map
map showing the runoff distribution depth by a contour connecting the points of equal runoff depth
4.2.3
hydrograph
graph showing the variation in time of data such as stage, discharge, velocity
[SOURCE: UNESCO/WMO, WMO-No. 385, Section 2 No. 733]
4.2.4
stage-discharge relation
rating curve
curve showing the relation between stage and discharge of a stream at a hydrometric station
[SOURCE: UNESCO/WMO, WMO-No. 385, Section 2 No. 1172]
4.2.5
storm -runoff relation curve
curve showing the relation between the storm and the corresponding runoff produced by it
4.2.6
flow-duration curve
curve showing the percentage of time during which the flow of a stream is equal to or greater than
given amounts, regardless of chronological order
[SOURCE: UNESCO/WMO, WMO-No. 385, Section 2 No. 570]
4.3 Hydrological computation
4.3.1
bench-mark station
observation station that records the hydrometric data which helps in hydrologic computation
4.3.2
typical year
representative year
year that has hydrologic characteristic values close to the design value, along with its spatial and
temporal distribution, which is used as the design basis
4.3.3
hydrologic series
series composed of hydrologic characteristic values in chronological order
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4.3.4
series representativeness
extent of closeness of statistical property of the selected sample to the overall statistical property
4.3.5
design hydrograph
hydrograph of discharge, etc., at a certain frequency, for design of hydropower plants
4.3.6
reservoir back water
rise in water level upstream of the reservoir along the channel stream, after the reservoir is filled
with water
4.3.7
frequency analysis
process of ascertaining the statistical parameters and design values of hydrologic variables from
the existing hydrologic data according to the statistical characteristics of a certain hydrological
phenomenon
4.3.8
return period
recurrence interval
long-term average time interval between a hydrological event of a specific magnitude and an event with
equal or greater magnitude
[SOURCE: UNESCO/WMO, WMO-No. 385, Section 2 No. 1234]
4.3.9
design frequency
frequency of a certain hydrologic feature used for planning and designing any structure
4.3.10
design annual runoff
annual runoff corresponding to the design standard and its annual distribution
4.3.11
naturalized computation of runoff
analysis and computation of runoff data for that volume of river flow which is influenced by the human
activities in the catchment
4.3.12
naturalized water volume
volume of water to be considered while computing runoff as the river flow decreases or increases due
to the influence of human activities
4.3.13
annual distribution of runoff
distribution process of annual runoff by month, ten-day period, or daily
4.3.14
mean annual runoff
long-term average value of annual runoff
4.3.15
design flood
flood adopted for design purposes
Note 1 to entry: It can be the probable maximum flood, the total amount of flood or a flood corresponding to
some adopted frequency of occurrence (e.g. 50, 100, 200 or 500 years), depending on the standard of safety to be
provided.
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4.3.16
probable maximum flood
PMF
flood that can occur under probable maximum precipitation
4.3.17
design flood for construction period
flow value that meets the temporary flood control design parameter during the construction period
5 Terms related to engineering geology
5.1
topography
study of all kinds of natural features and forms on the earth surface
5.2
geomorphology
study of all kinds of relief form on the earth surface
5.3
geologic structure
forms of deformation or displacement of rock stratum that make up the earth crust, under the action of
the earth’s internal forces
5.4
lithology
composition, colour, physicochemical properties and structure of the rocks that make up the rock
formation
5.5
hydrogeology
study of phenomena of change and movement of groundwater in nature, including groundwater
distribution and formation rules, physical properties and chemical composition of groundwater,
groundwater resources and their rational utilization, adverse effects of groundwater on engineering
construction and mining, and their mitigation
5.6
physical geology
ecological processes and phenomena which are produced by the external and internal forces of the
earth and adversely affect engineering construction
EXAMPLE Faults; landslide; collapse; karst; suffosion; earthquake; debris flows; weathering; frost heave;
thaw collapse; surface erosion.
5.7
weathering of a rock mass
process and phenomenon relating to the change in organizational structure, mineral chemical
composition and physical behaviour of a rock mass under the combined action of solar radiation,
temperature variations, wind, water (ice), gas and biological factors
5.8
landslide
phenomenon of rock mass, earth mass or debris moving down a slope under gravity
5.9
rockfall
phenomenon of rock falling abruptly down a steep slope
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5.10
unloading deformation
deformation of surface rock and earth mass due to the adjustment of internal stresses caused by
unloading, which occurs either due to natural geologic processes or engineering activity
5.11
creep
phenomenon of surface rock and earth mass moving slowly down a slope
5.12
debris flow
mudflow
sudden flood carrying a lot of solid matter like sediment and rocks, which takes place in a mountainous
area, in most cases due to a rainstorm or intense melting of ice and snow
5.13
reservoir leakage
phenomenon of water loss from a reservoir through the rocks and earth mass of the reservoir basin,
which can result in a loss of water volume and can also affect the stability of the dam
5.14
reservoir bank immersion
phenomenon of groundwater level rise in the area surrounding a reservoir zone due to water storage
in the reservoir, and resulting in secondary geological hazards like swampiness, salinization and
deterioration of the foundations of structures
5.15
reservoir bank caving
reservoir bank collapse
phenomenon in which caving of a bank slope occurs due to changes in the stability of the bank slope
under the effects of water level changes and wave action in the reservoir, after or during the process of
water filling
5.16
upward extension of reservoir deposition
phenomenon where back water is gradually elevated due to the continuous deposition of reservoir
sediment, which causes the reservoir tail silt to develop upstream
5.17
limit state of sediment deposition in a reservoir
state of reservoir siltation having ceased as it reaches the equilibrium of sediment transport
5.18
geophysical prospecting
method for determining the geological structure as part of engineering investigation by observing,
analysing and studying the differences in the physical properties of different geological bodies, and in
combination with the relevant geological data
5.19
exploratory drilling
application of the mechanical engineering technology of deep drilling to determine the profile of the
formation and retrieve strata samples to obtain the relevant geological parameters
6 Terms related to hydraulic engineering and energy
6.1
daily regulated hydropower plant
regulation of the supply of uniform inflow from the utilizable reservoir capacity, over a day, to handle
the daily power demand of a hydropower plant
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