Inversin R. Allen Micro-hydropower Sourcebook

Подождите немного. Документ загружается.

MICROFICHE

REFERENCE

LIBRARY

A project of Volunteers in Asia

By: Allen R. lnversin

Published by: NRECA International Foundation

1800 Massachusetts Ave., NW

Washington, DC 20036

Available from: NRECA International Foundation

1800 Massachusetts Ave., NW

Washington, DC 20036

Tel: (202) 857-9696

Reproduced with permission.

Reproduction of this microfiche document in any form is subject to the same

restrictions as those of the original document.

mctical

mentation

Countri

ICRO-LWDROBOWER

SOURCEBOOK

A Practical Guide to

Design and Implementation

in Developing Countries

by Allen R. lnversin

NRECA International Foundation

Washington, DC.

MICRO-HYDROPOWER SOURCF3OOK

NRECA International Foundation

1800 Massachusetts Avenue, N.W.

Washington, DC 20036

202-857-9696

reproduced or distributed in any form or by any

means without the prior written permission of the

publisher, excepting brief quotes used in connection

with reviews written specifically for inclusion in a

magazine or newspaper.

Library of Congress Catalog Card Number: 8641178

First printing, June 1986

Second printing, June 1990

Printed in the United States of America

Cover design by Gail L. Thompson

Additional copies of this book cau be ordered from the NRECA International Foundation.

Order forms, with publication and shipping costs, can be found at the back of this book.

PREFACE

Although worldwide interest in harnessing small-hydro-

power resources by means of micro-hydropower plants

(less than about 100 kW) is increasing, few published

guides exist for those implementing such projects.

Some publications deal primarily with larger small-

hydropower plants, leaving developers of micro-hydro-

power sites with few options but to reduce the s&e of

designs and approaches to implementation that are more

appropriate for large plants. Consequently, such publi-

cations unconsciously promote the development of

micro-hydropower schemes that do not take advantage

of the unique factors encountered in implementing

plants at the “micro’ end of the small-hydropower

range-factors which must be considered if this resource

is to be harnessed cost-effectively. Other publications

cover micro-hydropower technology but are incomplete,

for example, making only cursory mention of power

canals, even though a survey of micro-hydropower

plants around the world would indicate that power

canals are used at most sites. 4nd finally, most publi-

cations are written primarily for a western audience and

address western needs within the context of western

standards and realities.

Although those implementing micro-hydropower plants

have gained a wealth of experience during the last

several decades, few have documented their efforts.

Therefore, beginning with my personal efforts at

implementing a micro-hydropower project in Papua New

Guinea 10 years ago and continuing with numerous over-

seas consultancies with NRECA the last 5 years, I have

gathered technical inEormation and practical exper-

iences that address the needs of those interested in

implementing micro-hydropower schemes in developing

countries. In this Sourcebook, I present detailed

descriptions of many aspects of planning and imple-

menting such schemes and document experiences from

around the world.

Small hydropower can make a substantial impact in

developing countries where significant waterpower

resources exist and where economically viable alterna-

tives are few. This publication focuses on these coun-

tries’ needs and meeting those needs within the particu-

lar constraints found there. Although the theory of

micro-hydropower applies universally, conditions found

in developing countries make certain designs and

approaches used in industrialized nations less applicable

there. The reader must keep this in mind. For example,

where water resources are abundant and energy needs

are modest, less emphasis needs to be placed on maxi-

mizing turbine efficiency (especially because greater

efficiency implies greater cost and therefore less

accessibility to the technology). Turbines c,zn then be

fabricated locally rather than be imported. Where labor

costs are low and labor abundant, there is no need for

expensive, capital-intensive designs, which would again

restrict accessibility to this technology. And where

power requirements are simple, there is no need to incur

the costs of the sophisticated hardware necessary to

meet exacting western standards.

The technology associated with micro-hydropower

plants in developing countries spans a much broader

range of options than that for large-hydropower plants.

Penstocks, fur example, can range from 25 mm plastic

pipe snaking downhill to a 1000 mm steel penstoak with

massive concrete anchor blocks designed to maintain

stability on whatever foundation they may rest. Elec-

trical frequency may be controlled by sophisticated

governors or plants may be operated with no governing

whatsoever. In addition to generating ac power, micro-

hydropower plants can generate dc power or even

mechanical power. The Sourcebook is therefore faced

with the challenging task of covering each of these

options. The reader must also realize that even though

an option may not be appropriate Eor d larger hydro-

power scheme, it may still represent a valid approach

under a new set of circumstances. It is only by chal-

lenging conventional approaches that viable micro-

hydropower schemes can be developed.

In some countries, local technical expertise has been

developed, otten by trial and error. For these persons,

the Sourcebook can provide a reference and guide to

help them build on their experiences. In other coun-

tries, local expertise is not readily available and consul-

tants may be employed. However, few consultants have

experience either in implementing cost-effective micro-

hydropower schemes or in the conditions encountered in

rural areas of developing countries. Also, the high costs

of consultants can :;ignificantly increase the cost of

implementing a scheme. For these reasons, resorting to

consultants is often not a viable option. In such cases,

the Sourcebook can serve as a detailed primer for per-

sons with basic technical aptitude, covering many

aspects of planning for, designing, and implementing

micro-hydropower schemes.

The Sourcebook is a preliminary effort to prepare a ref-

erence book which covers many of the aspects of plan-

ning and implementing micro-hydropower schemes in

developing countries. Although many more useful

experiences and additional information might be added

to those already included in this publication, it seems

appropriate to make available the material already

gathered. In so doing, I hope that in addition to provid-

ing useful information, the Sourcebook encourages read-

ers to submit information bzdxir experiences for

future editions and that it provides a foundation on

wnich to build a more comprehensive reference. I also

hope that future editions can cover other areas of

interest, such as mechanical and electrical end uses and

their implications on system design and plant operation,

approaches for managing micro-hydropower plants and

programs, options for tariff structures and their social

and financial implications, and operation and mainte-

nance of small plants.

Anyone implementing micro-hydropower schemes is

invited to suggest which topics already included in the

Micro-Hydropower Sourcebook should be expanded upon

and what new topics should profitably be included in a

subsequent edititn. And anyone who has already imple-

mented micro-hydropower schemes is invited to submit

written descriptions accompanied by drawings and

photographs (preferably black and white) of his efforts

which might be of value to others undertaking similar

projects. Any comments or general suggestions would

also be welcomed.

Allen R. Inversin

Micro-Hydropower Engineer

International Programs Division

National Rural Electric Cooperative Association

1800 Massachusetts Avenue N.W.

Washington, D.C. 20036

Phone: (2021 857-9615

Telex: 64260

Cable: NATRECA

ACKNOWLEDGMENT

The Micro-Hydropower Sourcebook was initiated in 1981

under a Cooperative Agreement between the National

Rural Electiic Cooperative Association (NRECA) and

the Office of Energy of the U.S. Agency for Interna-

tional Development (USAID) as part of a broader USAID

effort to assist developing countries in their efforts to

harness indigenous renewable energy resources. -3e

Sourcebook has been completed with the support of the

NRECA International Foundation, a newly formed non-

profit organization.

The idea of a publication to address the needs of those

implementing micro-hydropower schemes in developing

countries had its roots in my initial work in Papua New

Guinea &NC), where Professor Jack Woodward first

introduced me to this field. During his last year as head

of the Department of Electrical and Communication

Engineering at the PNG University of Technology, he

initiated the implementation of a micro-hydropower

scheme requested by the villagers of Baindoang. When

he returned to the University of Auckland in 1977 to

head the Department of Electrical Engineering, I found

myself in the driver’s seat and had my first hands-on

experience implementing a micro-hydropower project.

At the same time, Ian Bean, an agricultura! develop-

ment officer stationed at the remote government out-

post of Pindiu, began implementing very small micro-

hydropower plants of rudimentary design in four isolated

mountain communities in PNG. While learning from his

experiences, I found his enthusiasm at meeting the chal-

lenge of adapting a sophisticated technology for use in a

setting where modern tcchnol lgy is largely unknown

contagious. The desire to assist others in meeting this

challenge has been an instrumental factor in deciding to

write this book.

During the past 5 years while I have been working part

time on the Sourcebook, numerous people around the

world have contributed in one way or another. I am par-

ticularly indebted to the following individuals who have

generously shared their time and experiences with me:

Dr.

Abdullah, Dean, Faculty of Engineering of the

North-West Frontier Province (NWFP) University of

Science and Technology in Peshawar, Pakistan, who

accompanied me on several occasions on site visits to

the NWFP where he had implemented several dozen

schemes and patiently answered my innumerable ques-

tions; Andreas Bachmann, who, while with the Swiss

Association for Technical Assistance (SATA) and later

with UNICEF, was involved in a variety of renewable

energy projects and shared with me numerous publica-

tions he had prepared on his activities as well as time to

visit projects in the field; Chartdanai Chartpolrak with

the National Energy Administration (NEA), who accom-

panied me on visits to micro-hydropower schemes in

Thailand for which he was responsible; Rupert Arm-

strong Evans from Cornwall, England, who has a vast

body of experiences from his full-time involvement in

the manufacture of hydropower equipment and the

implementation of micro- and mini-hydropower schemes

in the United Kingdom and overseas; Jaime Lobo Guer-

rero of the Universidad de 10s Andes in BogotEi, who is

committed to designing technologies to make them

more accessible to those in rural areas and eagerly

shared the results of his work with me; Rik Hothersall,

who also became involvad in the field of micro-hydro-

power while teaching in PNG and kept me informed of

his efforts; Dale Nafziger, who shared his photographs

and experiences gained while working with the United

Mission to Nepal (UMN); Domingo Wong, who accom-

panied me on visits to sites that the Instituto de Recur-

SOS HidrLulicos y ElectriEicacIon (IRHE) had imple-

mented in Panama and freely shared with me project

successes as well as shortcomings; and Robert Yoder, an

engineer sensitive to the needs and problems found in

rural areas, with 8 years of experience with the UMN,

who was my guide and translator on a 2-week trek

through the nil1 region of Nepal to visit schemes imple-

mented by the UMN, contributed to the case study on

Nepal, and showed by example that micro-hydropower

technology can indeed be viable in rural areas oE devel-

oping countries.

Others have shared their experiences from implement-

ing or managing their own schemes: staff of the Alter-

nate Hydra Energy Centre in Roorkee, India, imple-

menting schemes and undertaking research in hydro-

power generation and productive end uses; Geoff Bishop,

3 mining engineer who was implementing a 220 kW

scheme to provide power to the mission station of the

Eglise Episcopale du Burundi in Buhiga and to an admin-

istrative center and agricultural school in Karuzi;

Githuki Chege, a simple farmer in Kenya with several

water-powered mills and an eagerness to try something

new; Brot Coburn, who was involved in several renew-

able energy technologies in Nepal and implemented a

micro-hydropower scheme near the base of Mt. Everest:

Bernard C&tinon, a French coop&ant, who managed the

implementation of several schemes for the Ministry of

Rural Development in Burundi; Martin Dietz, who was

involved in a cooperatively administered micro-hydro-

power scheme with the UMN in Nepal; Gary Duncan and

Mike Smith, two Peace Corps vc!unteers who were

undertaking an ambitious micro-hydropower project in a

vii

remote part of Liberia; Peter Garman, who research&d

water-current turbines on the Nile in the Sudan; Harry

Langhorne, a private individual who built his own plant

from scratch, which is still providing the base power to

his home in the Appalachian Mountains in Virginia,

before it became in vogue; P&e Landolt and P&e

Pristt, who managed micro-hydropower plants supplying

power to their mission stations in Musongati and Giheta,

Burundi, respectively; Graham Leschke, who managed a

scheme in PNG and accompanied me on visits to other

plants in the area managed by missions; Soheyl Motta-

hedah, an Iranian-born Canadian committed to develop-

ment of the rural areas in eastern Zaire and founder of

the Soci6t6 de DBveloppement Rural du Zaire

(SODERZA), who built his first turbine with no prior

experience and implemented a complete project in the

space of only a couple of months; Harald Mucker, a

German engineer directing a program for implementing

micro-hydropower plants in the Department of Cusco,

Peru, for the Proyecto Minicentrales Hidroe&tricas

(PROMIHDEC), using locally fabricated turbines; the

staff of the Small Hyde1 Development Board (SHDB) of

Nepal involved in the implementation. of a number of

small-hydropower plants around the country; Bruno

VSgtli, an enterprising Swiss *vho was singlehandedly

constructing a road across a &.Jrtion of PNG and accon-

panicd me on an exhausting, all-day trek to visit a

micro-hydropower plant in Bz-ndi; John Wood, who

designed and built an ingenious automatic rack-raking

device for his plant in Ireland; and Gary and Connie

Young, who rehabilitated and managed a plant that pro-

vided power to the school and hospital complex of the

Mission Evangelique des Amis at Mibimba, Burundi.

In addition, a number of individuals have assisted with

this effort by reviewing, or in some cases contributing

substantively to, portions of the Sourcebook. These

include Dr. Maurice Albertson, Gfessor in the Civil

Engineering Department of Colorado State University;

Dr. Roger Ardt, Director, and Dr. John Gulliver, Asso-

ciate Professor, from St. Anthony Falls Hydraulic Labo-

ratory at the University of Minnesota; Bard Jackson,

Principal Engineer wRith NRECA’s International Pro-

grams Division; Martin Johnson, President of The John-

son Company in Montpelier, Vermont; Mike Johnson,

President of Hydro-Tech Systems Inc. of Chattaroy,

Washington; Ed Kramer, former General Manager of

Himal Hydra and General Construction Pvt. Ltd. of

Nepal; Dr. Pedro Restrepo, Systems Analyst with

Dynamics Research Corp.; and Dr. Calvin Warnick,

Professor Emeritus at the University of Idaho.

Finally, preparing the Micro-Hydropower Sourcebook

would have been a signficantly more difficult and time-

consuming undertaking had it not been for the assis-

tance of a number of individuals: Elizabeth Graham,

who not only edited portions of this publication but also

made innumerable contributions throughout which

shaped the final form of this publication; Darrell McIn-

tire, who stuck with it over several years to carefully

prepare most of the illustrations in their final form;

Barbara Shapiro, who conscientiously and carefully

edited the entire publication; Kitty Anderson, who

inputted innumerable drafts and revisions on the word

processor, never

knowing when they would end; and

Carol King, who patiently took all the pieces and laid

them out in their final format.

viii

27ABLEOFCONTENTs

Preface v

Acknowledgment vii

‘t’hble of contents ix

I. INTRODUCTION

Need for energy for rural development 1

Micrehydmpower: An appropriate energy source 1

Perceived obstacles to viable micmhydmpower schemes 4

Overview of the Micro-Hydropower Sourcebook 5

II. MEASURING HEAD AND DISCHARGE

Lntroduction 9

Measurement oi discharge 9

Bucket method 10

Velocity-ama method 11

Determining the area 12

Determining the stream velocity 12

Float method 13

Velocity-head rod 13

Current meter 14

Deternming discharge 15

Weir method 16

Salt-dilution method 19

Slope-area method 19

Stage-discharge method 20

Moasuroment of hoad

Using a level 22

Using a clinometer

Us@ a pressure gage 24

Using an altimeter 24

III.

STREAhMtIW CHARACXEIUSTICS AND DESIGN FMW

Introduction 27

Schemes using less than annual minimum streamf!ow 27

Schemes using greater than annual minimum streamflow 28

Gaged sites 28

Data collection 28

Data processing 29

Ungaged sites 32

Estimating mr?an annual flow 33

Using runoff data 33

Using ratio of areas 36

Correlating flows 38

Estimating minimum flow

Estimating a flowduration curve

Determining power and energy potential from a flow-duration curve

Alternative turbine configurations 42

N. SITE SELECTION AND BASIC LAYOUT

Introduction 47

Is the topography suitable for hydropower generation?

Developing the basic layout 49

Locating the intake

Nature of the streambed

Bends along the stream

Natural features along the stream

Competing uses for water

Ease of accessibility

Locating the powerhouse

Case examples 57

SalleriKhialsa (Nepal) 57

Musongati (Burundi) 58

Buhiga (Burundi) 58

Gih6ta (Burundi) 59

Bishalalo (Zaire) 61

Ruyigi (Burundi) 61

Mardan (Pakistan) 61

v. CIVIL WORKS

Introduction 63

Qualitative overview 64

Dam or weir

Increasing head 65

Providing storage 65

Diverting flow 67

Intake 67

Power conduit 68

Forebay 72

Penstock 74

Powerhouse 77

nilrace 78

Design and construction details

Dams and weirs

Intakes 84

Power conduits 96

Dotermining canal dimensinns and slope

Velocity in a canal 96

Roughness coefficient

Cross-sectional pmfiie 98

Pmcedure 99

Excavation 104

Canal lining

104

Brick or stone-masonry

106

Concrete

107

Soil-cement

108

Drainage

108

Fs~board and spillways

109

Dmp structures 110

Circumventing obstacles

112

Flumes 112

Inverted siphons

115

Culverts

116

Sizing low-pressure conduits

118