0305-750x(76)90082-6] vaclav smil -- intermediate energy technology in china

7/29/2019 0305-750x(76)90082-6] Vaclav Smil -- Intermediate Energy Technology in China

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Worl d Development, 1976, Vol. 4, Nos. 10/l 1, pp. 929-937. Pergamon Press. Printed in Great Britain.

Intermediate Energy Technologyin China

VACLAV SMIL*hiversity of i ldunitoba

Summary. - Intermediate energy technology - construction and operation of small projectsusing mass labour participation and local materials, minimizing capital investment andcombining modern and traditional approaches - has become an important part of Chinasenergetic?. Construction of small energy projects originated during the aborted Great Leap, buta rational - and apparently successful - expansion dates only since 1969. Small mines nowproduce almost one-third of the countrys raw coal, and small hydro-stations generate one-thirdof Chinas hydroelectricity. Methanogenic fermentation is increasingly used in South China toproduce biogas and the first steps have been taken in introducing small solar collectors.

I. INTRODUCTIONIncreasing numbers of experts have been

questioning the transfer of the advanced,capital-intensive and highly efficient Westerntechnology into developing countries ~ andarguing in favour of the developmental modelcombining the modern and the traditionalapproach as the only sensible way of modern-ization in populous Third World nations.

Ernst F. Schumacher, perhaps the mostinfluential proponent of this new approach,outlined four fundamental rules of the newtechnology required to support an economybased not on goods but on people: 1. Makethings small where possible. 2. Reduce thecapital-intensity because labour wants to beinvolved . . 3. Make the process as simple asyou can . . .violent. 4. Design the process to be non-

China, the largest and the most populous ofall developing countries, has been forced bynecessity to adopt the intermediate technologyapproach based on very similar principles: anyeffort to modernize her vast and backwardcountryside is hardly imaginable in any otherway. Walking on two legs, that is developingnot only large complex enterprises of the modernsector but also small simple projects in ruralareas, has been a leading dictum of the Chineseeconomy ever since the late 1950s. Althoughthe achievements have been mixed, the basicsoundness of the approach cannot be doubted.

Adoption of intermediate technologies inChinas energetics has been especially

important. While energy output ofenterprises has increased dramatically

largesince

1949, virtually all of this production has beendestined for major industries and urban areas;moreover, the countrys sparse and overloadedtransportation network has made any long-distance, large-scale fuel transfers to the ruralareas difficult and costly. Production of fuelsand electricity by small rural enterprises hasthus played the crucial role in rudimentarymodernization of the Chinese countryside.Small-scale developments in the countrysenergy industries have been predominantlyconcentrated in three areas: coal mining, hydro-electricity generation and biogas production.

II. SMALL COAL MINESMassive opening of small outcrop mines had

a spectacular - though ill-fated ~ beginningduring the years of the Great Leap Forward(1958-60). The native pits campaign became,together with the erection of little backyardiron furnaces, the chief embodiment of Maoseconomic delusions about instantaneousindustrialization. Some 110,000 pits were inoperation by the end of the first Great Leapyear (1958), engaging the incredible number of20 million Chinese peasants.3 Pit coal output,

* Most of the material in this article is drawn fromChapters 2-4 of my book, China s Energy: Achi eve-ments, Problems, Prospects, and is used here withpermission of Praeger Publishers, Inc., New York.

929


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930 WORLDDEVELOPMENTtotalling 3.11 million tons in 1953 and still over7.5 million tons in 1957, surpassed 50 milliontons in 1958.4 Pit extraction was supplementedby mass construction of primitive cokingbatteries.

Increases in native pit extraction continuedin 1959 - but further expansion was obviouslyunsustainable. Much of the hastily expandedand badly disorganized pit output, often ofappallingly low quality, was wasted; the life-time of many small mines was ephemeral; alarge part of the production was consumed inan equally ephemeral iron-making campaign. Infact, it is very likely that human and animalenergy necessary just to open, operate andmaintain many small mines surpassed theiractual energy yield6 while, at the same time,draining the farm production of its essentialhuman and animal energy inputs.

After the collapse of the Great Leap in 1960the coal industry was thrown back to near the1957 level and small mine output declined byabout 60% (from over 66 million tons in 1960to about 26 million tons in 1961). Productionstarted to climb in the mid-1960s but most ofthe new small mine capacity has been addedsince the end of the Cultural Revolution(1969).This new wave of small mine diffusion hasdiffered substantially from the aborted GreatLeap expansion. The basic rationale is,undoubtedly, the same: small mines can beopened up and brought to their full capacitymuch faster than the large enterprises; they canbe run at a relatively low cost, relying onabundantly available labour supplemented, ifnecessary, by simple, locally-producedmachinery; consequently, they can yield quickand favourable returns on a limited investment,enabling the accumulation of funds for farmmechanization, light rural industries, chemicalfertilizer and farmland capital construction.

However, the actual execution is different.Opening of new small mines (i.e. mines run byadministrative regions, counties, communes andproduction brigades) is now done in a ratherorderly manner, with some essential planningand, if one is to accept official claims, withmuch more real success: close to one-third ofChinas raw coal output originates in smallmines,7 a higher share than at the height of theGreat Leap native pits campaign (Table 1;Figure 1).In some southern provinces small minesaccount for an even higher share of raw coaloutput (Table 2), and are instrumental inlessening the costly dependence of southernChina on northern coal.

Table 1. Raw coal productionin China I949 ~ 74SmallTotal production Small mines output mines(million tons) share

194919521953195719581959196019611965196919701971 320.001972 340.001973 365.001974 390.00

32.43 1.4566.49 2.9669.68130.73230.00300.00280.00170.00220.00250.00300.00

3.117.5051.3466.0766.5426.0032.0055.0075.0083.0092.00102.00112.00

4.54.54.55.722.322.023.815.314.522.025.025.927.028.028.7

Source: V. Smil, Energy in China: achievements andprospects, The China Quarterly, No. 65 (March 1976),Table 5, p. 62.400-

300-

zto2 200-e

Figure 1. Total and small mine (shaded area) raw coalproduction in China, I949- 74.While the total southern coal output nearly

doubled between 1965 and 1973, local pitproduction increased six times.g Every provincesouth of Yangtze - and even Tibet - has now alarge number of permanent or seasonal smallmines and their further moderate expansion,


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INTERMEDIATE ENERGY TECHNOLOGY IN CHINA 931Table 2. Numbers and producti onshares of smal l coal mi nesin South China

Province or Percentage ofautonomous Number of the total rawregion small mines coal outputAnhwei 138 _Chekiang >400 64Fukien 5 052Hunan 1 500 >60Hupeh 719 25Kiangsu 770 46Kwangsi 460 25Kwangtung 1 330Kweichow _ 43Yunnan 2 600 50Sources: NCNA and provincial broadcasts,SWB, FE/W799/A/13-15, 27 November1974; FE/W860/A/6-9, 14 January 1976.

both in capacities and in numbers, willundoubtedly continue.

It is, of course, undeniable that - especiallywhen judged in terms of modern Westerneconomics - the Chinese small pit coalextraction has many drawbacks. Raw coaloutput is usually of a lower quality than thelarge mine production; economies of scalecannot be attained in thousands of scatteredenterprises; labour productivity is rather lowand the lifespan of many outcrop mines is oftenvery short. However, these criteria are hardlyappropriate when the main concern is tointroduce the technology into the rural areaswithin reach of poor peasants.

III. SMALL HYDRO-STATIONSConstruction of small hydro-stations has

been perhaps the most meaningful applicationof intermediate energy technology in China,especially during the recent past.

The programme was originally initiated as apart of massive water conservancy work duringthe Great Leap years, when as many as 100million people were engaged in buildingdykes, dredging and regulating streams,repairing reservoirs and digging new irrigationcanals. Thousands of small stations with thetotal designed capacity of 900 MW were begunin 1958 and a very ambitious plan predicted a1,000 MW total in 1962 and as much as 2,500MW in 1967.The reality was much less impressive. Duringthe year between October 1957 and September1958, 4,334 small stations with aggregate

capacity of 13 1.5 MW were put into operation,and another 200 MW were finished in 1959.*Then the Leap collapsed and the massive con-struction of small hydro-stations wasabandoned - to be resurrected only in thelatter half of the 1960s with most of theprojects starting after the end of the CulturalRevolution (1969).General guidelines for the development ofsmall hydro-stations are quite simple :dependence on local resources, maximum thriftand construction speed. Stations are built withfunds accumulated locally through agriculturalproduction or light industry activities; centralfunds are released only for necessary assistancein design, manufacturing of power generatingequipment or training of future operators.Labour and construction materials arestrictly local. Traditional mass methods ofconstruction - large numbers of peasantsmarshalled to a site and performing all taskswith the aid of chisels, picks, shovels,shoulder-poles, straw or bamboo baskets andpull carts - are used in almost all cases and thework is often accomplished in a very shorttime. 3 Small dams are either rock-filled orearth-filled structures, requiring only aminimum of cement, steel and timber. Manycounties are now even producing their own smallwater turbines and generators, transformers,cement poles, aluminum wire and switches, andtraining new electricians and operators. 4

Some 50,000 small and medium hydro-stations were in operation in 1973 and over60,000 in September 1975, concentratedoverwhelmingly in the rainy southern half ofChina. Yangtze Basin has about one-third of allstations, 6 approximately four-fifths of thetotal are in the eight southernmost provincesand Kwangtung alone accounts for almost 20%(Table 3; Figure 2, overleaf).Naturally, the typical installed capacities ofthese stations are very small: available figuresfor the southern provinces (Table 3) give theweighted average of roughly 48 kW per hydro-station. 7 Consequently, the total capacity ofChinas small hydro-projects was around 2,000MW in 1973 and about 3,000 MW in 1975.18In many provinces small hydro-stations aremuch larger than indicated by the national orregional averages. Table 4 overleaf summarizesmost of the information available aboutcapacities on the county level, showing averagesover 100 kilowatts in some areas of Hupeh,Kiangsi, Kwangtung, Chekiang and Yunnan.A 1974 report claimed a county in Kwangsi-Chuang Autonomous Region was engaged inbuilding a one-megawatt hydro-station, i.e. an


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932 WORLD DEVELOPMENT

Miles

200 400 600Kilometers

Figure 2. Numbers ofsmallhydro-stations in South China (estimated totals forthe end of 19 75).

Table 3. Smal l hydro-s ta t ions in China Table 4. Small hydra-s ta t tons rn Chinaprov inc ia l drs t r ibut ion selec ted county s tatmt lcs

Provinceor region

Number Installedof small capacity

hydra-stations kWAveragecapacity Date of

kW referenceKwangtung (a)Szechwan (bHunan ()Yunnan Cd)

Fukien (e)Kweichow (Kwangsi (g)Chekiang (h)Kansu (0Liaoning (i)Tsinghai (k)Tibet (I

11,740 688,000 58.60 x-19756 000 300,000 50.00 x11-19746 000 200,000 33.33 V-19765 000 x-1974

4 600 155,000 33.69 IX-19734 290 IX-19744 000 114,000 28.72 x-19733 600 x-1973>400 IV-1976

278 16,800 60.43 X11-1972146 22,800 156.16 VII-1974100 IX-1975

Sources: (a) Kwangtung provincial service, SWB, FE/W847/A/24,8 October 1975.

(b) NCNA in Chinese, SW& FE/W812/A/5 , 5 February1975.

(c) Hunan provincial service, SWB, FE/W879/A/6 ,26 May 1976.

(d) NCNA in English, SWB, FE/W799/A/l l, 30 October1974.

(e) NCNA in English, SWB. FE/W/743/A/S, 26 September1973.

(0 NCNA in English, SlVB, FE/4699/CI, 10 September1974.

(g) ;9,3! in English,SWB, FE/W747/A/lO, 24 October(h) ibid.(0 NCNA in En&h, SWB, FE/W875/All, 28 April

1976.(i) Liaoning provincial service, SWB, FE/W718/A/9,

26 March 1973.(k) Tsinghai provincial service, SWB, FE/W799/A/lO,

30 October 1974.(I) Peking home service, SWB, FE/W849/A/lO,

22 October 1975.

COUllty ProvinceNumber Total Average

OS capacw capacitystations kW kW

I:eng-kaiLo-tingChieh-siYang-shanYungLuchuanChien-yangNing-huaChin-huaFengchingChuan-nanI-chunSheShih-talChuang-hoTa-WUChing-lung

KwangtungKwangtungKwangtungKwangtungKwangsiKwangsit.uk1.mFukienChekiangYUIlIUllKlangslKiangsiAnhweiAnhweiHUllUlHupehHupeh

306226155139215120126

5014144

5729

16031193779

10.90013,29016,000

7 50010,325

8 0003 3641 290

20,0004 7202 38090133 000

6412 3704 2003 100

35.6258.81

103.2353.9648.0266.6726.6925.80

141.84107.2741.75

310.7918.7520.67

124.74113.51

39.24

Sources NINA in English and in Chmese, provmc~al services,SWR. l-EIW747iAi9: I~EIW755iAill: E;E/W758/A/15;FE/W760/A;9; FEjWj86/A/4; E/WBlO/A/IO;E/W845/A/21;FE/W847/A/l5,4425;FE/W849/A/9;E/W854/A/5-.

installation 1O-30 times larger than a project oftypical size. I 9 On the other hand, the TientsinElectra-Driving Research Institute is trial-producing seven types of miniature hydro-turbogenerators (0.6-l 2 kW capacity) suitablefor isolated moyztain villages with scatteredwater resources. There is also a series ofremarkable small hydro-stations in southernKwangtung using low head tidal power forsingle (ebbing) or bi-directional generation.

Small and medium hydro-stations havecontributed immensely to the basic electrifica-tion of the Chinese countryside. In 1974 theyaccounted for about one-third of the totalhydro-generation (i.e. about 9 billion kWh) andproduced most of the power for more than 70%of communes and about 50% of production


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INTERMEDIATEENERGYTECHNOLOGYINCHINA 933brigades in the country which had electricitysupply at that time.2 Private rural electricity consumption stillremains very low - usually only one or twolow-voltage bulbs are allowed per house-hold - but power available for small localindustries (including fertilizer production) aswell as for irrigation and drainage, and for suchdiverse primary processing tasks as grainthreshing and milling, fodder crushing, oilextraction or timber sawing often representsthe first step toward modernization in manyChinese villages.Certainly no less important than powergeneration is the regulation of water suppliesfor irrigation and flood control provided bysmall reservoirs. This multi-purpose nature ofsmall hydro-projects is perhaps the bestassurance of their further vigorous development.

IV. BIOGAS PRODUCTIONBiogas generation has been spreading

throughout some of Chinas rural areas sincethe early 1970s. The procedure is, at least inprinciple, rather simple, and the processesinvolved are well known.

Animal dung, night soil, pieces of vegetation(crop stalks, straw, grass clippings, leaves),garbage and waste water are sealed up ininsulated containers (digesters, pits) and left todecompose. Digestible organic materials(liquids, proteins, most starches) are brokendown by acid-producing bacteria and thevolatile acids are, in turn, converted byanaerobic methanogenic bacteria into a gaswhich is typically composed of 55-70%methane, 30-45% carbon dioxide and a trace ofhydrogen sulfide and nitrogen. Besides theversatile low pressure medium-caloric gas(between 5,300 and 6,300 kcal/m3; puremethane has 9,345 kcal/m3), the process yieldsan organic fertilizer of outstanding quality andcan c;snsiderably improve sanitation of ruralareas.

Small-scale, non-commercial production ofbiogas (called also dungas and in India gobargas; the Chinese reports usually use the namemarsh gas) was tested in India and in Europein the late 1930s but it has received greaterworld-wide attention only during the pastdecade.24The first Chinese attempts date from theGreat Leap period,25 but a massive, andapparently well organized, campaign topopularize the technology started only a fewyears ago in Szechwan, where the numbers of

fermentation pits have been growing at a veryfast rate. Chung-chiang county pioneered theprocess in winter 1970 and some 800 digesterswere operating by 1972.26 More than 30,000tanks were built throughout the province bythe end of 1973,27 the total was 209,000 ayear later (with 169 000biogas production)2 containers used forand twice as many(410,000) digesters were reported to be inoperation by the middle of 1975.29 Theleading area in the province - and the wholecountry - is Mien-yang county where, as ofJuly 1975, some 60,000 pits were completedand another 20,000 were under construction,with more than 60,000 peasant householdsusing biogas for cooking and lighting.3o

The recent Chinese reports stress, as mightbe expected, the advantages of the method.Biogas production is undoubtedly aneconomical method to solve fuel problems inmany rural areas as it conserves local fuelwoodor imported coal and kerosene, upgrades vegetalrefuse and human and animal wastes into anexcellent fertilizer and contributes to a cleanerenvironment.3 With minor equipmentmodifications biogas can be used to powerinternal combustion engines and to substitutefor diesel oil in small electricity generators. Andit is, of course, a clean and convenient fuel forhousehold cooking and lighting.

Consequently, the biogas campaigncontinues to spread the technology throughoutthe country. About 50,000 containers wereoperating outside Szechwan in the summer of1975, mostly in Tung-ting Hu area in Hunan, inKiangsu, Kiangsi, Kwangsi, Kwangtung andother regions of South China. The NewChina News Agency (NCNA) claimed thatbiogas pits are used not only north of theTsinling Shan and Huang Ho but even north ofthe Tien Shan and north of the Great Wal1.32

The effort is supported through nationalconferences (organized by the ChineseAcademy of Sciences, State PlanningCommission and Ministry of Agriculture andForestry), trainin of technicians (100,000 inSzechwan alone), $3 manufacturing the simplegas stoves and lamps, rubber or plastic pipesand pressure gauges, and by designingdifferently shaped fermentation pits.Construction of containers is claimed now tobe simpler and cheaper: cement consumptionwas reduced from 400 kg to less than 150 kgand the cost dropped from 100 to 40 yuan fora typical ten cubic metre digester which is,when properly managed, sufficient to supply aSouth Chinese family of five with enough fuelfor cooking and lighting.34 Peasant families are


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934 WORLDDEVELOPMENTthus encouraged to dig their own pits and largerdigesters are built collectively to produce biogasfor fueling water pumps, farm processingmachinery and small-scalegeneration.35 electricity

But the biogas production is not withoutproblems. Certainly the most importantlimitation of the method is the impossibility touse it efficiently - or at all - in colder regionsof the country because of the thermal require-ments of the fermentation process.

Methanogenic bacteria, unlike their acidprecursors, reproduce rather slowly and arevery sensitive to environmental changes. Duringmesophilic fermentation the temperatureshould be kept in optimum range of 2&45C,without fluctuating more than *2C.36

While Szechwan Basin, Fukien, Kwangtung,Kwangsi and southern Yunnan - having highaverage ambient temperatures and less than fivefreezing days a year - are best suited formethanogenic fermentation (Figure 3),possibilities of widespread, economic biogasgeneration north of Tsinling Shan and HuangHo (i.e. in areas with more than 100 freezing

days a year) are - the claims of encouragingresults notwithstanding - practically riiL3 7Even in warm climate with concrete

digesters well-insulated in dry soil a consider-able drop in efficiency and eventual cessationof the biogas production can occur if the pH isnot maintained near neutrality (6.8-7.4), ifmaterials fed into a digester do not have aproper carbon/nitrogen ratio (between 25 and35), and if the sludge lacks the necessaryquality and liquidity to balance the acid andthe methanogenic bacteria.38 Other operationproblems are associated with sand accumula-tion, scum build-up and removal and collectionand loading of human and animal waste.

On the assumption that digesters can operateviably only south of Huang Ho 1 have estimatedthe total Chinese potential biogas generation atsome 60 billion cubic metres annually,equivalent to about 50 million tons of hardcoal.3 9 The full realization of this potential ishighly unlikely - but all future attempts tointroduce the fermentation technology insuitable regions are mostthe associated problems,

desirable. In spite ofwell-managed biogas

Figure 3. Annual frequency of freezi ng days in the eastern hal f ojChina (w arm Szechwan Basin stands out conspicuously ).


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INTERMEDIATE ENERGY TECHNOLOGY IN CHINA 935production offers a clean, efficient and, what iscertainly most important, a non-exhaustiblesource of energy which can be tappedinexpensively to benefit indefinitely a largesegment of Chinas population.4o

V. SOLAR ENERGYThe latest addition to Chinas intermediate

energy technologies has been the use of solarenergy for water heating and cooking. While aneffective large-scale utilization of solar radiationfaces many difficult obstacles,41 simple solarfurnaces - with practical applications in house-hold cooking, space and water heating, cooling,water desalination and crop drying - areeconomically viable. They can be used inter-mittently and a satisfactory, though not highlyefficient, operation can be achieved withunsophisticated and relatively cheapmechanisms.The first series of 1,000 small solar stoveswas experimentally produced by the ShanghaiNo. 15 Radio Factory in 1974 to be usedmainly by peasants on the outskirts of thecity.42 The simple device has a paraboliccollector and will boil three litres of water in 20min and cook a kilogram of rice in 15 min, therates comparable with those for a small coalstove.

Use of solar stoves has since spread to severalprovinces; unfortunately no figures areavailable, except for Honan where 2,300 stovesand eight solar water heaters were built by theend of 1975.43 As for the price, a folding typesolar stove for boilinKansu costs 15 yuan. 54

and cooking produced inThe most advantageous conditions for small-

scale solar technology exist in Tibet, whereannual sunshine averages 3,000 hr and isaccompanied by low air density, low humidityand low turbidity: a 280 m* glass absorber nowheats water for a public bath in Lhasa andsimilar smaller units, as well as solar stoves forheating and cooking,the region.4 s are operating elsewhere in

VI. CONCLUSIONSThe advantages of intermediate energy

technology for China are indisputable. Smallprojects - while providing fuel and electricityfor development of diverse local lightindustries, for agricultural modernization andalso for household consumption - introducemodern technology in a way which allows forlarge-scale labour participation and reducescapital investment to the essential minimum.

Moreover, the benefits go further: part ofthe energy output which goes for privateconsumption raises the standard of living andhelps in easing household work; many peasantsacquire various basic technical skills necessaryfor more sophisticated work to be done in thefuture; substitution of fuel and electricityproduced in large enterprises by localproduction brings not only considerablesavings, but it greatly reduces the need forenergy-intensive transportation and trans-mission of primary energy.

Environmental implications of small energyprojects are mostly positive: availability of coal,electricity and biogas reduces, or eveneliminates, the need for firewood, grasses andcrop residues (traditional fuels in the Chineserural areas), which can be either conserved orused for cornposting or as fodder. Irrigation andflood control roles of small dams might be, inmany instances, economically more importantthan power generation. Improvement ofhygienic conditions and concomitant reductionof infections and parasitic diseases may resultfrom biogas generation. Biogas fermentationalso yields excellent fertilizer, representingfurther savings, doubly important in the era ofrising hydrocarbon prices mirrored by fastincreasing chemical fertilizer costs.

Based on these considerations, I would nothesitate to forecast the further diffusion ofsmall energy projects in China ~ and elsewherein the developing world.

NOTES1. Ernst F. Schumacher, Economics should begin successful, the Chinese - in departure from theirwith people, not goods, The Futurist, Vol. 8, No: 6 usual mode of extreme sketchiness, if not a near total(December 1974), p. 274; for details on Schumachers secrecy - are rather liberal in releasing information onintermediate technology see his book Small i s their performance. Critical evah&on of theseBeauti ful : Economi cs as if Peopl e M att ered (N ew materials shows only rare implausibilities or in-York: Harper, 19731, 290 pp. consistencies. Thus, in my opinion, the official

Chinese claims in these areas ought to be accepted as a2. Since these enterprises have been recently fairly reasonably accurate account of the reality.


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936 WORLD DEVELOPMENT3. Yuan-li Wu with H. C. Ling, Economic Develop-

ment and the Use of Energy Resources in Communi stChina (New York: Praeger, 1963), p. 44.

4. ibid., p. 40.5. While the conversion rate of the Chinese raw coal

output to hard coal equivalent was 0.71 for the FirstFive-Year Plan years, it dropped to 0.48 in the year1958: Yuan-li Wu with H. C. Ling, op cit., pp. 39,108-109.

6. It is unavoidable that a process in which energycost of primary energy surpasses the net yield cannotlx sustained.

7. New China News Agency (NCNA) in English,British Broadcasting Corporation, Summary of Wor ldBroadcasts (SWB), FE/W803/A/15, 27 November1974.

8. Virtually all of Chinas large collieries are north ofYangtze (in Anhwei, Shansi, Shantung, Hopeh,Liaoning and Heilungkiang). Costly transfer of thenorthern coal to the South has been one of the majorintractable problems facing Chinese energetics.Another obvious advantage is the saving of minetimber, a commodity in chronically short supply inChina.

9. NCNA in English, S& B, FE/W760/A/lO, 30January 1974.10. Very few small mines have any coal preparationfacilities and the fuel is thus used unwashed andunsorted, containing a large proportion of incom-bustible waste.11. Marion R. Larsen, Chinas agriculture undercommunism, in An Economic People of M ainl andChina (New York: Praeger, 1968), p. 241.12. Robert Carin, Power Industry in Communist China(Hong Kong: Union Research Institute, 1969), p. 144.13. NCNA in English, SWB, FE/W760/A/9, 30January 1974.14. NCNA in English, SWB, FE/W784/A/4, 17 July1974, and FE/W845/A/20, 24 September 1975.15. NCNA in English, SWB, FE/W756/A/14, 2January 1974, and FE/W845/A/20-21, 24 September1975.16. NCNA in English, SWB, FE/W799/A/9, 30October 1974.17. The smallness of these stations is perhaps bestindicated by a comparison. An average Americanelectrical range with oven has the power rating of 12.2kW: a typical small Chinese hydro-station could thusserve only four average American kitchen ranges.

18. This total capacity, composed of tens of tousandsof units and built and maintained by millions of theChinese peasants, is about half of the power of theworlds single largest hydro-stations (Grand Coulee,Sayany, Krasnoyarsk).19. NCNA in English, SWB, FE/W784/A/4, 17 July1974.20. Midget water-turbine generators for mountainvillages, Peki ng Review , Vol. 18, No. 21 (23 May1975) pp. 30-31.21. Power generation by low water head, Ko-hsuehShih- yen (Scienti fi c Experi ment), No. 1 (January1973), pp. 4-5.22. NCNA in English, SWB, FE/W849/A/20, 8October 1975. Minor portions of rural electricitysupply come from small fossil-fueled stations or frominterconnections with high voltage grids (mostly invillages near large cities).23. For detailed description of anaerobic fermentationand methane power plants see, among others, L. JohnFry, Practical Buil ding of M ethane Power Plants fbrRural Energy Independence (Santa Barbara: StandardPrinting, 1974); Proceedings of Int ernati onal BiomassEnergy Conference (Winnipeg: Biomass EnergyInstitute, 1973); Chaman Kashkari, Energy Resources,Demand and Conserv at ion (New Delhi: Tata, McGrawHill, 1975), pp. 86-94; Energy Primer: Solar, Water,Wi nd and Biofuels (Menlo Park: Portola Institute,1975) pp. 142-147.24. In the 1960s biogas development programmeswere started in Taiwan and in India (Gujarat andMaharashtra).25. NCNA in English, Survey of Peoples Republi c ofChi na Press (SPRCP), No. 5864 (2 June 1975), p. 24.26. Marsh gas used in rural China, Peki ng Review ,Vol. 16, No. 2 (12 January ?973), p. 22.27. Szechwan provincial service, SWB,FE/W760/Alll, 30 January 1974.28. Szechwan provincial service, SWB, FE/W812/A/6,5 February 1975.29. NCNA in Chinese, SWB, FE/W834/A/14, 9 July1975.30. Popularizing the use of marsh gas in rural areas,Peki ng Review , Vol. 18, No. 30 (25 July 1975), p. 15.31. Besides reducing the felling of trees, biogasgeneration saves much labour spent in cutting andtransporting firewood; part of plant residues, whichwas traditionally burned (with very low efficiency)and could not be used for fertilizer or as animal feed,can now contribute to production of very efficient


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INTERMEDIATE ENERGY TECHNOLOGY IN CHINA 937fuel and can be used afterward as fertilizer as well; 38. According to the Chinese experience (Office ofsome straw and dry plant tops are also saved for Science and Technology of the Mien-yang County,additional fodder. An interesting example of various Szechwan) the best combination for digester loading issavings affected by biogas in South China is described 10% of human waste, 30% of animal waste, 10% dryin Mi-lo County, Hunan, exploits methane in a big stubble and 50% water: Native method of manu-way, Jen-min Jih-pao (Peoples Daily), 19 January facturing and utilizing marsh gas, Ko-hsueh Shih-yen1976, p. 3. (Scientific Experiment), No. 5 (May 1973), pp. 32-34.32. NCNA in Chinese, SWB, FE/W834/A/13314, 9 39. This figure must be seen merely as an order ofJuly 1975. magnitude estimate.33. Szechwan provincial service, SWB, FE/W812/A/6, 40. Approximately threequarters of Chinas rural5 February 1975. population (i.e. at least 500 million people) live in

areas where biogas production is viable.34. NCNA in Chinese, SWB, FE/W834/A/l3, 9 July1975. For comparison, the greater part of Chinese 41. Above all, intermittent flow of radiation,peasants earns 12 yuan or less per person per month atmospheric scattering and absorption, and need forfrom communal activity on the farm: J. S. Prybyla, A very large collection surfaces and heat storages.note on incomes and prices in China, Asian Survey,Vol. 15, No. 3 (March 1975), p. 270.35. NCNA in English, SPRCP, op. cit.36. Thermophilic fermentation (SS-60C) is even moretemperature sensitive, while psychrophilic bacteria(0-7C) are unsuitable for digester biogas production.37. High, steady digester temperatures can be, ofcourse, maintained even in cold climate - but theheating may easily require more energy than isreleased in biogas by methanogenic bacteria.

42. Solar energy stoves, Peking Review, Vol. 17, No.40 (4 October 1974), p. 38.43. Honan provincial service, SWB, FE/W866/A/2, 25February 1976.44. Kansu provincial service, l?anslations on PeoplesRepublic of China, No. 327 (21 November 1975), p.15.45. NCNA in English, SWB, FE/W866/A/lO, 25February 1976.

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