A project of Volunteers in Asia Small Scale Hydropower Technologies - --.- by J,J, Tiemersma and N.A. Heeren Pub3 ished by: Stichting TOOL Entrepotdok 68A/69A 1016 AD Amsterdam THE NETHERLANDS Available from: same as above Reproduction of this microfiche document in any form is subject to the same restrictions as those of the original document. CFNTER FOR A"PRLPRIATE TECHNOLOGY .------___ -- -.- . . TEChNlC.'ii DEVLcOPMEElT WI-K-I DEVEiOPiNG COUNTRIES Published and compi led by TOOL Foundation Technical Development with Developing Countri es Entrepotdck hSA/69A 1018 .\D Amsterdam The Netherlands C A T Center fdr Appropriate Technology Stevinweg 1 '028 CN Delft The Netherlands Typists: Petra Dorsman and Martin Rijn. Lay-out: Martin Rijn and Niq. Heeren. ‘I;e 2.72 2:’ data, methods and/or restllts, given in this publicatio,,, ?, s 7t your own rise. The ,? e ! Ji- t Yxiverslty of Technology declares herself (through CAT) rZOZ responsible for any damage arising from the use QJ these. Frontcover shows a cross-flow turbine. AN OVEXALL VIEW OF HYDROPOWER TECHNOLOGIES FOR S SCALE APPLIANCES J.J.Tiemersma N ..LZ.Heeren Commissioned by: the Directory General for environmental Hygienics of the Dutch Ministry of Housing, Physical Planning and Environment Cease your work, ye maidens, yd who laboured at the mill, sleep now:and let the birds sing to the ruddy morning; for Ceres has commended thg waternymphs to perform your task; and these, obedient tc her call, throw themselves upon the whee 1, force round the axle tree and so the heavy mill. This is, in a lyrical way, the first known reference to 3 watermill, in the form of an epigram by Antipater of Thessalonica, written about 85 BC. TABLE OF CONTENTS INTRODUCTIONAL SECTION c 1 . PREF.ACE page 5 ? ti. SCOPE OF THIS PUBLICXTION GENERAL SECTION page 5 3. blE.I\NIyGS OF SJU1.L SCALE HYDROPOWER page 8 1. BASICS OF HYDROPOWER page 12 5 . CON1'ENTIOS:1L HYDROPOliER TECHNOLOGIES page 17 b . SjLJ.LL SC:JLE HYDROPOliER TECHNOLOGIES page 22 - TURBi\ii TYPES . PRACTICABILITY SECTION page 30 Y. h..1TERWLEi DE\'l;I~Ol~~lEST AND USE page 12 9. PRACTICE E.!d>lPLES page 63 I. GESEMTISG ELECTRICITY page 63 II. MOTiVE POKER page 70 11;. KATEi? FUMPING page 73 IO. APPLICABILITY LIST page 83 11. CC)STS OF SMALL SCALE HYDROPOWER APPENDIX 12. DESIRED FURTHER STUDIES 1 T LITERATURE AND MASUFACTURERS d. page 84 page 88 page 91 1’1~~ use oi \iaterpower for indu.5tl.i 11 and domestic purposts has generatecl interest since Grecian culture. In the last decades, interest has even increased, as this power source has the appraisable qualities of being renewahle and non- polluting and giving more oil- and import independence. Especially these qualities make water-power an excellent option both in developing countries as in economies like Europe and Northern America. Import independence is most attractive for developing countries. In the Western World the non-polluting aspects suits to attemptions made to reduce distulbance of the environment caused by exhausts from thermal electricity generation. In the past most of the most suitable sites for hydropower statlor:s are being used on a large scale. Technologies on this scale !1ax-e proven well and are being employed and published war 1 ,jwide. Now that energy has become a topical issue, also locations with a smaller waterpower source become interesting in the lies tern Kcrld. ‘ihese locations and the respective lower outputs need their own techniques. This is why the numbers of producers of smaller waterpower installations as well as the number of field tests and publications hereabout increase. Aiike in the &ester-n World in medieval times and thereafter, power needs in countries with a developing economy are of a smaller amount. Also these needs are to be fulfilled locally, caused by greater distances and lack of good (POWerJinfra- structure. This is why, apart from national supply schemes, the small scale schemes are of imnortance also. liowtsver, in both areas, waterpower has the constraint of needing relative high capital investments. This counts also for small especially when techniques are copied from those for big scale applications. 3 Fortunately researchers and even product maKers have started to ‘1 ‘, develop an own appro; ch to small scale waterpower technology. , Aspects herewith are ;o try to lower the capital costs hy minimi.z\ng :i civil constructions and by designs or mechanical installations whlxh $ can be mzde easy and locally with local materials. i ;, , Close attpntion should he p:xiJ to these rich’ dc1.clorJmcnts ;IS \ : The authors of this publication are !Giq. Heeren: working at TOOL Foundation, Amsterdam and Jan Jaap Tiemersma, scientific officer at Delft University of Technology, Department of civil engineering, group of hydraulic engineering, and contributor to feasibility studies of hydropower projects in the Netherlands and in developing countries. This study has been commissioned by the Directory General for environmental tlygicniss of the Dutch Ministry of Housing, of this and information Physical Planning and Environment. On assignment ?linistrs the follo\iing gives 3n overall view of, on sma spread about the possible techniques and devices hydropower , and is meant to stimulate the know ledge. 11 scale .ing of the Xt is hoped that anyone thinking of small polluting power generation can extend ins i hydropower techniques. scale and noI;- ght in available 4 23COPE OF THIS PUBLICATION ‘The pllr!?osc 0 f this study i-s to give a survey- of n,~e~z.‘T:r tccilnologics to use hydropower on a swell scale~:-;~~. limition a net output of 300 to 50n kilowatts _C.,,i;: be adopted, which range can Se divided into mic’.h iydro (up to 100 kilowatts) and mini hydro (100 a~ it10 kW). i;;e~izP remark is given to those configurations Lhat neeJ litt,e civil constructions and invcstler’nts, and 3re es, :c bsild. r h t‘ rqh,abiliej and. Feasibiii:) cf these techniques are ~, ;‘-cussed 2nd irj(’ Li:ations are gj ve--\ on some aspects k;!-? ,. ‘c need further Ii:vestig:+tions. Most s;!bjects appear 35 exd:,;mies of pras t, cc ( manufactured items :,-?d labora tory s tudi &s . While reading, one shouid keep in mind to compare small scale hydropower with other alternatives like biogas, solar energy an3 windpower. Always diesel generation and electricity grid connection should be compared in economical, environmental and social studies. In the following the present technologies on smaii scale hydropower will be discussed in a general section and illustrated in a practicability section. In the general section first some definitions are given together with some remarks on small scale hydropower (Chapter 3). For a good understanding Chapter 4 describes the theoretical basics of hydropower. In Chapter 5 implementation technologies are dealt with, as is done in Chapter 6 on small scale implementation in special. To give an overall view of the types of the most important component of a hydropower unit, the turbine, Chapter 7 will give some details. 5 The practicability section starts with Chapter 8, _ where the development and use of hydropower in former days are surveyed. These technologies can improve understanding or even can give ideas for today’s implementations, In Chapter 9 some practice examples of present small scale implementations are given. A summary of applicabilities of small scale hydropower devices is listed in Chapter 10, while in Chapter 11 some remarks are made about the costs of small scale hydropower. In appendical section at last blanks in small scale hydropower technologies are summarized in Chapter 12 and a Chapter 13 lists refering and further literature and addresses of manufacturers of small scale hydropower units . 6 GENERAL SECTION 7 -3.MEANINGS OF SMALL SCALE ._ -lF ~ c ‘,-~:.---.-“I-~.--.‘-- ptxei r.. HYDROPOWER DEFINITION OF TlYE TERM The word “hydropower” is to be understood as any capability of water to do a kind of labour, to produce %qower that may be.useful to men and men’s activities. tale of hydropower utilit;r both costs, head e determining. Altrhough several different und in literature, the border line d small hydro at 1000 kW -seems 8 / , 1 Micro hydro more than 1000 2 500-1000 100-500 less than 100 The term small hydra often stai;;ls also for mini and micro sizes and is often confused with. ~~s1.1 scale hydro. A definition of small scale hydropowkx can be given as any mini or micro hydro implemented with- investments, little impact on the surround small installation size and serving a li demands. POTENTIAL The power of water depends on the amount of water per time unit (discharge) and the vertical height that water can be made to ‘fall (head). A site with a. great amount of water flow and a big head will make a big scale hydro- power plant. On earth however such places are scarce in comparison with those where either head or flow are not exorbitant or where both are relatively small. WEIGHING CONSIDERATIONS Compared with big scale implementation advantages of small-scale hydropower are : - Solution to problems of growing supply and of difficulties in supply of fuel , particularly in rural,isolated areas. - Help to promote socio-economic and cultural development of consumers and owners. - Technologies available that only require adaptations to specific conditions. - 1.0~ operating costs. - Cheap and simple maintenance due to simple technologies. - Little or no environmental impact. - Compatible with use of water for other purposes. Disadvantages and iimitations are : - High unit investments costs per installed kW. - High costs of preliminary and design studies in relation to total investments. - Utilization dependent upon the availability of resources near the point of demand. - Low head projects are vulnerable to fluctuations in stream flows , falling even to ( nearly ) zero. - Each plant requires separate installation of transmission facilities and eventual connection to electricity grid ) and possibly as many people to operate as it does to operate a big scale plant. 9 h INVESTMENTS Investments per installed kW raise as installed power IwGrs. Also investments are higher for low head implementing than for high head units. For mini hydro sets the installation costs lay between