a review of jatropha curcas: an oil plant of unfulfilled promise

A review of Jatropha curcas: an oil plant of unful®lledpromise

p

Keith Openshaw

Alternative Energy Development Inc., Silver Spring, MD, USA

Received 8 January 1999; received in revised form 21 March 2000; accepted 27 March 2000

Abstract

Jatropha curcas is a multipurpose plant with many attributes and considerable potential. It is a tropical plant thatcan be grown in low to high rainfall areas and can be used to reclaim land, as a hedge and/or as a commercial crop.

Thus, growing it could provide employment, improve the environment and enhance the quality of rural life. Theestablishment, management and productivity of jatropha under various climatic conditions are not fullydocumented. This is discussed and the gaps in the knowledge elucidated, especially its fertilizer requirements. The

plant produces many useful products, especially the seed, from which oil can be extracted; this oil has similarproperties to palm oil. The costs and returns of growing the plant and producing the plant oil are discussed andtabulated. Because it can be used in place of kerosene and diesel and as a substitute for fuelwood, it has been

promoted to make rural areas self su�cient in fuels for cooking, lighting and motive power. This strategy isexamined and found not viable. Oil for soap making is the most pro®table use. It is concluded that all markets forjatropha products should be investigated. If the full potential of the plant is to be realized, much more research isrequired into the growing and management of Jatropha curcas and more information is needed on the actual and

potential markets for all its products. 7 2000 Elsevier Science Ltd. All rights reserved.

Keywords: Jatropha curcas; Plant oil; Diesel/tallow substitute; Economic analysis

1. Introduction

Jatropha curcas (Linnaeus) is a multipurpose

bush/small tree belonging to the family of

Euphorbiaceae. It is a plant with many attributes,

multiple uses and considerable potential. The

plant can be used to prevent and/or control ero-

sion, to reclaim land, grown as a live fence, es-

pecially to contain or exclude farm animals and

be planted as a commercial crop. It is a native of

tropical America, but now thrives in many parts

of the tropics and sub-tropics in Africa/Asia. It

Biomass and Bioenergy 19 (2000) 1±15

0961-9534/00/$ - see front matter 7 2000 Elsevier Science Ltd. All rights reserved.

PII: S0961-9534(00 )00019-2

www.elsevier.com/locate/biombioe

pThere are over 200 articles on jatropha. Some important

ones have not been reviewed. One is a January 1996 paper by

H.J. Wiemer entitled ``Financial and economic analysis of the

Jatropha system'' published by GTZ. This study came to simi-

lar conclusions made in this article.

has few pests and diseases and will grow under awide range of rainfall regimes from 200 to over1500 mm per annum. In low rainfall areas and inprolonged rainless periods, the plant sheds itsleaves as a counter to drought.

Jatropha is easy to establish, grows relativelyquickly and is hardy, being drought tolerant. It isnot browsed, for its leaves and stems are toxic toanimals, but after treatment, the seeds or seedcake could be used as an animal feed. Variousparts of the plant are of medicinal value, its barkcontains tannin, the ¯owers attract bees and thusthe plant has a honey production potential; itswood and fruit can be used for numerous pur-poses including fuel. Of particular importance,the fruit of jatropha contain viscous oil that canbe used for soap making, in the cosmetics indus-try and as a diesel/kerosene substitute or exten-der. This latter use may be of importance whenexamining practical substitutes for fossil fuels tocounter greenhouse gas accumulation. Also, likeall trees, it ®xes atmospheric carbon, stores it inwood and assists in the build up of soil carbon.

However, for several reasons, both technicaland economic, the full potential of jatropha is farfrom being realized. The growing and manage-ment is poorly documented and there is little ex-perience in marketing its products. Thus,frequently, growers do not achieve the optimumoutput of products, such as the fruit that wouldbring the greatest rewards. Neither do they havemuch information about the most lucrative mar-kets. In many instances, markets have not beenexplored or properly quanti®ed, nor have thecosts or returns been assessed to supply thedi�erent products to these markets. Therefore,actual or potential growers, especially in the sub-sistence sector, may be reluctant to invest timeand money in a crop that only has promiserather than concrete rewards.

Some of the current strategies used to promotejatropha may be sub optimal and could act as adeterrent instead of a stimulus in promotingrural development. Thus, it is timely to examineproblems encountered in the growing and use ofjatropha, achievements to date and the presentstrategy in promoting this potentially useful andversatile plant.

2. Present strategies for promoting J. curcas

Jatropha is widely grown in Mexico, Nicara-gua, N.E. Thailand and in parts of India. It isnow being promoted in southern Africa, Brazil,Mali and Nepal. There are several governments,international organizations, national bodies andNGOs promoting the planting and use of J. cur-cas and other oil bearing plants. These includethe World Bank, the International Plant GeneticResearch Institute, Austrian and German Techni-cal Assistance Programmes, the RockefellerFoundation, Appropriate Technology Inter-national and Intermediate Technology Develop-ment Group Ð (USA and UK based NGOs)and the Biomass Users Network (BUN) andPlant Oil Producers Association of Zimbabwe[1±8].

Two principal objectives of these initiatives areto use oil plants and their products for economicand environmentally sustainable rural develop-ment and to make rural areas self su�cient inenergy, especially liquid fuels. Where possible,this is to be achieved without displacing otheragricultural crops or competing for land that hasa higher opportunity in other applications. J. cur-cas was chosen as one of the prime plant oilspecies, especially for Brazil, Nepal and Zim-babwe. Areas in these three counties, that alreadywere growing such species, were chosen as dem-onstration sites for the utilization of plant oilwith appropriate technology. In order to achievethe stated objectives various goals were formu-lated. These goals can be summarized as follows:

. To promote the use of plant oil as a fuel instationary or mobile engines for water pump-ing (irrigation), grain milling, transportationand electrical generation.

. To encourage the use of plant oil as a viablerenewable energy option for cooking, lightingand heating.

. To reduce poverty, especially that of women,by stimulating economic activities in ruralareas by using the products of such plants forthe manufacture of soap, medicines, lubricants,chemicals, fertilizers, insecticides.

. To improve the environment through land rec-

K. Openshaw / Biomass and Bioenergy 19 (2000) 1±152

lamation, erosion control, enhanced soil ferti-lity, a better microclimate and greenhouse gas(GHG) mitigation.

The successful implementation of these goalsshould lead to:-

. An improved quality of life for rural people.

. A reduced consumption of ®rewood and resi-dues in rural areas.

. An increase in the gross domestic product(GDP).

. A reduction of expenditure of imported fuelsfor rural consumption.

. A decrease in the deforestation rate.

. A more productive use of land.

. Expanded options for carbon dioxide abate-ment.

. The establishment of decentralized technologychains based on the use of plant oil.

. The promotion of South-based new technologydevelopment.

While the overall objectives are laudable and arethe aim of most governments, NGOs and donoragencies, the goals to accomplish these objectivesmay be contradictory. Several agencies are pro-moting jatropha oil as an energy source, to thedetriment of other uses and other plant products,without fully analyzing the economics of growingand producing the oil, its technical appropriate-ness and the cost of substitute fuels. Using plantoil for motive power and cooking may lead tothe growers and producers subsidizing the endusers and forgoing pro®table markets for the oiland/or other product. Thus, promoting plant oilfor these uses may deter sustained economicgrowth, hinder improvements to the quality oflife and delay poverty alleviation.

The oil from jatropha is an important productfrom the plant, but it is only one of a number ofproducts. Too much emphasis seems to havebeen placed on the use of this oil for motivepower. There are still teething problems with theuse of jatropha oil in diesel engines1 and it is

very doubtful if the plant oil can compete withdiesel fuel at its current price, even if a ``carbontax'' is imposed on fossil fuels. Thus, at present,there are technical constraints and economic fac-tors against using jatropha and other plant oilsfor motive power. These should be fully con-sidered and compared to alternative uses of theoil, rather than pursuing what may be sub-opti-mal solutions.

Sooner or later, as (fossil fuel) oil reservesdiminish and/or a substantial carbon tax isimposed worldwide on fossil fuels, carbon basedliquid fuels from biomass will become universallycompetitive. Meanwhile, countries have to gainexperience in the growing and use of versatileplants such as jatropha so that they will be in aposition to capitalize on this knowledge once theoil becomes competitive with diesel etc. This maybe achieved by looking at other uses for thejatropha plant and its products.

Another goal cited above which should bereexamined is the use of plant oil for householdcooking in rural areas to substitute for fuelwood.The cost of producing plant oil is usually muchmore than the cost of kerosene (or purchasedfuelwood). Yet rural people use kerosene spar-ingly for lighting, but rarely for cooking. Even ifplant oil can be produced at a comparable priceto kerosene, rural people are most reluctant topay for cooking fuel, be it plant oil, wood or ker-osene etc., if any form of biomass can be col-lected. If fuelwood is scarce, rural people burncrop residues and dung.

One of the above goals is to use jatropha oilfor cooking in rural areas in order to curtaildeforestation. However, the use of fuelwood forrural cooking causes little if any deforestation,although it may cause some woodland degra-dation [9]. By far the largest cause of deforesta-tion is clearing land for agriculture in response topopulation increase. In order to slow downdeforestation, apart from more e�ective familyplanning initiatives, agricultural productivity hasto increase. J. curcas could play a role throughland reclamation, erosion control, protection andimproving the microclimate.

Jatropha can be used to reclaim eroded landand other problematical sites. Jatropha hedges

1 Numerous engines have been ®eld tested with jatropha oil.

Performance tends to decline over time and maintenance is

the critical factor [10].

K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15 3

and shelterbelts can assist other crops on allland types by keeping out animals, improvingthe microclimate and providing humus to thesoil. It could also be promoted as a commer-cially viable crop on medium to high potentialareas. Thus, such plants should be regarded asbeing complimentary to agricultural cropsrather than competing with them. Several com-mercial crops may lend themselves to jatrophafencing or shelterbelts. These include co�ee,market gardening, ranching, tobacco farmingetc. Such valuable crops then can be grownwithout damage from browsing animals whileat the same time marketable goods may beproduced from the hedge itself.

Also, jatropha could be used as a substitutefor wire fencing and posts round ®elds, aswell as along roadsides and railway tracks. InMali, the principal reason for planting jatro-pha is as a hedging plant. A comparisonbetween the two types of fencing may showthat live fencing is much more cost-e�ectivethan wire fencing. Current experience shouldbe documented and potential sites listed byrainfall, soil type and present use. Jatrophashould not be con®ned to problematical sites,but used on all areas where it can complementother farming systems or where it has a com-parative advantage.

The jatropha plant has few insect or fungalpests and is not a host to many diseases thatattack agricultural crops. It is reported that, insome areas of Zimbabwe, the golden ¯ee bee-tle (Podagrica spp) can harm jatropha andthat it plays host to the ``frog eye'' fungus(Cercospera spp), common in tobacco [11].How serious such pests are could be investi-gated and recommendations made, if any, oncontainment of such threats. This may pre-clude jatropha being used as fencing intobacco areas.

Using the seed cake as a fertilizer is being pro-moted as an income-generating activity for the

oil processor. The products from the fruit Ð theexocarp (coat), shell and processed seed cake Ðare rich in nitrogen, phosphorous and potassium(NPK) and/or can be used as soil improvers.Thus, the seed cake when added to the soil canincrease agricultural productivity, while at thesame time save foreign exchange by replacingmineral fertilizers. However, jatropha is not anitrogen ®xing species and to maintain its pro-ductivity, fertilizers will have to be added to thesoil. One publication recommends that the seedcake be returned to the jatropha sites to maintainfertility [12]. Thus, the farmer may have to buyback the cake and/or use other fertilizers. Amore pro®table use for the cake could be as ani-mal feed, if non-toxic varieties can be grown,2 orthe toxic seed cake detoxi®ed at a low cost.

In summary, when promoting such plants as J.curcas, costs and bene®ts of the various alterna-tives should be listed, without prejudice. Manage-ment practices, specifying di�erent options,should be tabulated and all the actual or poten-tial markets researched, together with incomeand expenditure information. This should allowgovernments, donors, NGOs and above all, po-tential growers to make informed decisions. Inthe past, expectations have been built up aboutplant oil, some of which have turned out to beunfounded or inappropriate. There are still mis-conceptions and gaps in the knowledge about theeconomics, management and markets of jatrophaand its products. These will now be discussed.

3. Management of J. curcas

Partial information is available about the silvi-culture and management of jatropha. It is knownthat jatropha can be established from seed, seed-lings and cuttings. Plants from seeds develop ataproot and four lateral roots, whereas it hasbeen reported that cuttings do not develop a tap-root [2]. The best time for planting is in thewarm season before or at the onset of the rains.In the former case, watering of the plants isrequired.

The recommended spacing for hedgerows orsoil conservation is 15±25 cm. apart (within and

2 Developing non-toxic varieties of jatropha will remove its

ability to act as a hedging plant, because animals may now

eat the leaves and fruit.


between rows) in one or two rows and 2±3 m by1.5±3 m for plantations [6]. Thus there will bebetween 4000±6700 plants per kilometre for asingle hedgerow and double that when two rowsare planted. The number of trees per hectare atplanting may range from 1100 to 3300. Widerspacing is reported to give larger yields of fruit,at least in early years [2]. Further information isrequired on to the planting practices, manage-ment and the spacing employed, but one booklethas been produced on management practices inGujarat, Maharashtra and Rajasthan states ofIndia [12].

Growth of the plants is dependent on soil ferti-lity and rainfall, especially the latter. Flower andseed production respond to rainfall and nutrients.A poor nutrient level will lead to increased fail-ure of seed development [1]. Thus, it is importantto maintain soil fertility; this is contrary to state-ments made in some publications [13]. With onerainy season per year, there will be only oneannual fruiting; for irrigated crops, up to threefruitings can occur each year.

Woody biomass growth is not recorded in anypublication to hand, unlike seed production.Seed production ranges from about 0.4 to over12 t/ha/y, after ®ve years of growth [6].3 Thisrange in production must be from low to highprecipitation. In Mali, where jatropha is plantedin hedges, the reported productivity is from 0.8to 1.0 kg of seed per metre of live fence [3]. Thisis equivalent to between 2.5 and 3.5 t/ha/y. It isassumed that these yields are of air dry tonnesper hectare, with an average whole nut moisturecontent of about 10% (wet basis). There shouldbe a systematic study done on the yields of jatro-pha fruit and its components, especially the nut,and wood etc. by annual rainfall. The number ofrainy seasons per year and the nutrient level ofthe soil are two possible variables. Such infor-

mation is necessary in order to give the growersand the users of the products an idea of theexpected yields and returns on investment.

Provided the nutrient level is su�cient, plantgrowth is a function of water availability, es-pecially in the tropics. Net primary production(NPP), which is the production of all types ofplant biomass, be it annuals, tree leaves, woodybiomass and fruit etc., ranges from an average of1 t/ha/y of above ground oven dry matter, (1.2 tair-dry) with an annual rainfall of 200 mm, to anaverage of 10 t/ha/y. (11.8 t air-dry) with a rain-fall of 1500 mm [14,15].

If management favours fruit productionthrough the application of fertilizers, about one-quarter each of the NPP in J. curcas may be inthe form of woody biomass, and leaves, with theremaining half being fruit, but of course, thisshould be tested. Plant growth, especially wood,is a function of age and rainfall as well as man-agement practices. It is reported that jatrophatrees/bushes live up to 50 years and reach aheight of 5 m. Like all perennial plants, it dis-plays vigorous growth in youth; this will tail o�gradually towards maturity. Good siviculturalpractice requires that hedges are trimmed andplantations are pruned or even thinned. Nor-mally, if say 1600 seedlings were planted per hec-tare, these would be thinned frequently, untilabout 400±500 trees remain at maturity. Toretain a high density, the plants would have to bepruned annually and thinned periodically. Simi-larly, hedges require trimming in order to containthem and to reduce competition.

Documentation is sparse on the managementof jatropha hedges and plantations. Already, thegrowers must be practising some form of man-agement. These practices could be recorded andthe best ones highlighted, as should be thegrowth ®gures. The growth and yield of woodmay be in proportion to nut yield, but somemanagement practices may a�ect yields of nutsand/or wood. The wood may be just as useful asthe fruit: thus obtaining optimum yields of allproducts may be the desired goal.

In Zimbabwe, the Agricultural Research Trust(ART) has laid down trials of di�erent prove-nances of J. curcas. Such research work is vital

3 It is assumed that these yields are in terms of seeds rather

than the whole (air-dry) fruit. Thus, the whole fruit yield per

hectare, per year, will range from about 0.9 to 26 t. On the

other hand, if these numbers are yields of whole (air-dry)

fruit, then the seed yield will range from 0.2 to 5.5 t/ha/y.

Therefore, it is important to specify what is being measured

(fruit, whole nut or seed [kernel]) and its moisture content.


in determining the most appropriate provenancesand the optimum management systems for thiscountry: it must be encouraged. The current sta-tus of this work may give an important insightinto the management and yield of jatropha inZimbabwe. Non-toxic varieties of J. curcas fromMexico were sent to Zimbabwe for planting [1,p. 203]. It may be that ART has these varieties intheir provenance trials. If successful, the nut and/or the seed cake could be used as animal feedwithout being detoxi®ed. If so, a cost comparisonshould be made between using the cake as ananimal feed or returning it to the soil to maintainfertility.

In Zimbabwe, the seed cake is being promotedas a commercial fertilizer, for it is rich in NPK.The ``cake'' contains about 6% N, 3% P and 1%K as well as traces of Ca and Mg [14]. Onetonne of seedcake applied to the soil is equivalentto applying 0.15 t of NPK [40:20:10] mineral fer-tilizer. The seed cake, being relatively rich innitrogen, implies that jatropha requires a nitro-gen rich soil to obtain a good seed production.This is because J. curcas is not a nitrogen ®xingplant. There are no reports of root associationswith (nitrogen ®xing) rhizobium, although ifphosphorous is scarce, mycorrhiza may be foundon the root system assisting with the uptake of P[6]. If nitrogen is not applied, then ¯owers mayabort and seed production decline [2]. An Indianbooklet on the management of jatropha rec-ommends the addition of farmyard manure andNPK to the planting hole and yearly top dres-sings of fertilizers including the seed cake [12].

There is little published information about thefertilizer requirements of jatropha. Many docu-ments assume that it is a plant with low fertilizerrequirements, but this is contrary to outputrequirements. The subsistence sector may not beable to a�ord mineral fertilizers, and/or the dis-tribution system may be poor. Growing jatrophain combination with nitrogen ®xing plants, es-pecially nitrogen ®xing trees, may be the mostcost±e�ective solution. There are many agro-for-estry trees which grow under variable climaticconditions, ranging from Prosopis spp in lowrainfall areas, to Sesbania spp and Leucaena sppwith rainfall above 1,000 mm. Investigations on

the fertilizer and soil pH requirements of jatro-pha should be a part of a detailed study into themanagement of J. curcas, if the promotion ofthis versatile plant is to have lasting success.

Considerable information is still requiredabout management systems and nutrient require-ments of J. curcas. Production levels by rainfalland over time of both wood and fruit, especiallythe nut, are important if people are to be encour-aged to plant and manage jatropha as a pro®t-able crop. The use of jatropha by itself or incombination with other plants to improve the en-vironment or to sustain the land use systemshould be documented so that a comprehensivepicture is built up about growing the plant underdi�erent climatic and management conditions.

4. J. curcas as an energy source

The oil from jatropha is regarded as a poten-tial fuel substitute. Diesel is a hydrocarbon with8±10 carbon atoms per molecule, but jatropha oilhas 16±18. Thus, the nut oil is much more vis-cous than diesel and has a lower ignition quality(cetane number). For these reasons, using the oildirectly in engines has not been fully tested overlong periods. In Europe, plant oils are usuallytrans-esterised (with alcohol and hydroxide) tobio-diesels with properties similar to mineral die-sel. This reduces their viscosity and increasestheir cetane number. However, this requires con-siderable investment and currently it is not cost-e�ective. Experiments have also been undertakenin Nicaragua.

A principal reason is that the price of crudehas been dropping in relative terms over the lastdecade. At present, jatropha oil is not cost com-petitive with diesel, except in exceptional circum-stances. Therefore, it is as well to re-examine theuse of the di�erent products from the jatrophaplant to determine if any are pro®table sourcesof energy.

The types of fuels which can be obtaineddirectly from the jatropha plant are wood, thewhole fruit and parts of the fruit burnt separatelyor in combination, namely the exocarp (coat),the nut shell and the kernel (or seed). After pro-


cessing, in which energy inputs are required,other fuel products can be made from the plantsuch as plant oil, seed cake and charcoal (fromthe wood or nutshell). All these products havedi�erent energy values and production costs.Table 1 gives the energy values of the variousfuels and Table 2 lists the possible end uses ofthese fuels together with other potential uses.

Processing increases the energy value of theproduct, but the overall energy availabilitydecreases unless a use can be found for the by-products. This is an important point that cannotbe over-emphasized. Removing the coat from thefruit increases its energy value by 20%, fromabout 21 to 25.5 MJ/kg. But if the coat is dis-carded, then there is an overall loss in energy ofabout 15%, because the whole nut is only 70%of the weight of the air-dry fruit. It may be that

the price commanded by the whole nut morethan o�sets the loss of energy in the discardedcoat, or a pro®table use can be found for thecoat. For example, it could be burnt in thehousehold or at the processing factory or usedfor non-energy purposes such as a soil condi-tioner. In such cases, the latter value has to beincluded in the overall pro®tability statement. Ineach situation, markets should be explored for allproducts and by-products and the most bene®cialline of action pursued.

In terms of unit weight, the kernel (seed)has 40% more energy than the whole fruitand jatropha oil nearly twice the energy value.But overall, the kernel has about 35% lessenergy and the oil about 70% less energy thatthe whole fruit, because of processing losses.Thus, while the unit energy value is enhanced,

Table 1

Energy values of various fuels from J. curcasa

Composition of the fruit

(%)

Fuel Ash content

(%)bMoisture content

(%)cEnergy value

(MJ/kg)dCoat Shell Kernel Recovery percentagee

Woodf 1 15 15.5 95±100

Whole fruitg 6 8 21.2 30 24 46 95±100

Whole nut 4 5 25.5 0 34 66 67±70

Coat 13 15 11.1 100 0 0 28±30

Shell 5 10 17.2 0 100 0 23±24

Kernel 3 3 29.8 0 0 100 44±46

Wood charcoal 3 5 30.0i 15±25

Shell charcoal 15 5 26.3i 15±25l

Plant oilh < 0.1 0 40.7j 11±18 [23±38]m

Seed cakeh 4 3 25.1k 29±35 [62±77]m

a Source: [1,16].b Ash content given as a % of dry weight (0% moisture content). All the ash can be used as a fertilizer.c Moisture content given as a percentage of the wet weight (moisture content wet basis Ð mcwb).d This is the low heat value. It is the energy that is practically available. For oxygenated (biomass) fuels, the di�erence between

the high heat value and the low heat value is about 1.3 MJ/kg at 0% moisture.e The recovery percentage is in relation to the air-dry wood raw material or the whole fruit.f Energy value of green wood (50% mcwb), 8.2 MJ/kg.g Energy value of fresh whole fruit (43% mcwb), 12.8 MJ/kg.h The plant oil and the oil cake are from the kernel only not the whole nut.i Fully carbonized charcoal.j Energy value per litre, 37.4 MJ (speci®c gravity 0.92).k Assume 70% seed cake and 30% oil from kernel.l Recovery percentage in relation to the shell input, not the whole fruit.

m The ®gures in brackets refer to the recovery percentage from the kernel.


as the degree of re®nement increases and the

fuel becomes a much more versatile product,

less energy is available if no use can be found

for the by-products. However, it is the total

net income from the sale of the di�erent pro-

ducts and by-products that should be the pri-

mary consideration, or at least the net income

plus an implied value for non-monetary pro-

ducts.

Apart from household cooking, potential mar-

kets are as fuel for brick, ®sh, tea, and tobacco

processing. It may be more pro®table to burn the

whole fruit and wood, rather than to produce oil

and charcoal. The energy value of the fruit is

equivalent to that of low-grade coal and it may

be easier to handle; its ash content is lower and

this ash could be sold as a fertilizer. A similar

argument can be made for the whole nut, but

there are costs in removing the ¯esh.

5. Markets for the products of J. curcas

For a country that is growing jatropha, a sur-vey should be done, by region or district, ofactual and potential markets for the products ofjatropha. Markets have to be researched and thequantities required by each end use recordedalong with the price of substitute products. Itmust be remembered that the growing and pro-cessing of jatropha products are but two stagesin the marketing process. Usually, there are othercosts involved such as storage, transport andmarketing plus pro®t margins. All these elementshave to be considered when determining pro®t-able end uses.

Bulk demand for the products of jatropha,such as the oil for industrial soap making dependon a constant and year round supply of raw ma-terial. Thus, even though supplying plant oil tothis market may be very pro®table, the quantities

Table 2

Potential end-uses of fuels from jatropha, plus other possible usesa

Fuel type Free (F) or for

sale (S)

End use of fuel Other possible uses

Small branches

and twigs

F Rural household (H/h) cooking. (May be

di�cult to burn because remains green for

long period)

Bean sticks, planting and fencing material

Large branches

and stems

F & S Rural & Urban H/h cooking. Service sector

and industrial use Ð tobacco barns, brick

stacks, boiler fuel, cooking in schools etc.

Building poles, fence posts, charcoal

production

Whole fruit F & S Rural & Urban H/h cooking. Service and

industrial uses Ð tobacco, brick, bakeries,

boilers, schools etc.

Ash used as a fertilizer

Whole nut F & S Rural & Urban H/h cooking. Service and

industrial uses Ð tobacco, brick, bakeries,

boilers, schools etc.

Ash used as a fertilizer

Exocarp (coat) F Rural H/h cooking Soil improver

Shell F & S Rural H/h cooking, industrial use Ð

tobacco, brick, boilers, etc.

Soil improver, charcoal production

Kernel F & S Rural H/h cooking, industrial use Ð

tobacco, brick, boilers, etc.

Animal feed (if treated) planting material

Wood charcoal S Urban H/h & non-H/h cooking Fine as soil conditioner

Shell charcoal S Urban H/h & non-H/h cooking Activated charcoal

Plant oil S Urban cooking, urban and rural lighting,

service sector and industrial uses, diesel and

kerosene substitute or extender

Soap making, lubrication oil, cosmetics,

medicine, cooking oil (detoxi®ed)

Seed cake F & S Urban H/h & non-H/h cooking, boiler fuel Fertilizer, animal feed (if treated)

a Source [1] and author's estimates.


involved could be beyond the present capacity ofthe growers. Surveys should be undertaken onthe estimated output of products, by region.Plans can then be drawn up to meet the demandsof particular industries, if pro®table.

Possible end uses for jatropha products aregiven in Table 2. These are divided into energyand non-energy uses. This list may not cover alluses and there may be speci®c uses in particulardistricts or countries. It is given as a guide whentrying to assess the market potential of the var-ious products from jatropha.

Several donor projects have concentrated onthe production of jatropha oil as a diesel substi-tute for engines and/or as a kerosene substitutefor cooking and lighting. In many developingcountries, diesel fuel is taxed less than petrol(gasoline) and kerosene has little if any tax;sometimes it is subsidized. Table 6 demonstratesthat at present jatropha oil is about three timesmore expensive than hydrocarbon fuels. Thus, asa general rule, the present day costs of diesel andkerosene do not make it attractive to produceplant oil as a substitute for these petroleum-based fuels.

Only where diesel and kerosene are scarce, dueto poor and intermittent distribution systemsand/or smuggling the fuel to other countriesoccurs, could it be cost e�ective to produce plantoil as a diesel substitute. Also, kerosene may bescarce because it is used as a diesel substitute orthe price is in¯ated because rural people buysmall quantities at a time. In these cases it maybe pro®table to use plant oil as an illumination(not cooking) fuel in rural areas. But it is unli-kely that there will be a market for such fuel inurban areas. Detailed studies should be carriedout of the availability and delivered price of die-sel and kerosene to the various locations whereplant oil is grown to determine if this oil cancompete with these fossil fuels.

In Zimbabwe, it is proposed to generate elec-tricity with plant oil in one project and to pumpwater for irrigation in another project. An econ-omic feasibility study was undertaken on thesetwo projects which showed they were marginal atbest [13]. No alternative analysis was done withdiesel as the fuel, but this should have been

undertaken for comparative purposes. Marginallyeconomic projects may be justi®ed on socialgrounds, but still they should use the cheapestfuel source etc. Just because a potential fuel isproduced in the vicinity is no reason for its use ifthere are cheaper alternatives. Besides, jatrophaoil and other products may have more pro®table(non-fuel) uses, some of which are listed inTable 2. This will now be elaborated.

6. Non-fuel uses of J. curcas

Jatropha is a woody plant and, therefore, itstwigs, branches and stems can be used for anumber of purposes, especially as fuel, sticks andpoles. Unfortunately, the twigs remain green fora long time and are di�cult to dry out and thusburn. If used as poles, they have a tendency tosprout. However, in some countries, the live poleis used to support vines such as the vanillinplant. It ¯owers profusely in response to rainfallor irrigation and can ¯ower up to three times ayear. Bees pollinate these ¯owers; thus it is poss-ible to have apiaries in association with jatrophaareas. The fruit is normally toxic, unless treated,but there are varieties that produce non-toxicfruit. If it can be detoxi®ed cheaply, or the oilextracted from toxic free varieties, it could beused in food preparation and the seed cake usedas animal feed. Latex and oil from the plant havemedicinal, pesticidal and mollusk control proper-ties. Tannin can be extracted from the bark andnutshell etc. and used to treat leather. A varnishcan be made from the oil and the leaves are afeedstock for silk worms.

For those districts, regions and countries thatdo not produce palm or similar oils, the mostlucrative non-food product could be the plantoil. Jatropha oil is similar to sun¯ower/palm oilsand tallow (animal fat). It contains a fatty acidand one of its uses is as a raw material for soapmaking. Jatropha oil has been used commerciallyfor soap manufacture for decades, both by largeand small industrial producers. For example, inIndia it is used by a large industry (HindustanLever). In Zimbabwe, soap is produced by smallinformal industries in rural areas using plant oil,


but one large manufacturer is interested in usingjatropha oil as a substitute for tallow. However,the monthly requirement of this industry alone is2000 litres of oil. To supply this demand, wouldrequire the equivalent of about 20,000 ha.Clearly, the present area, an estimated 2000 haequivalent, is only about 10% of the requiredarea to meet this demand alone.

In India, Nepal and Zimbabwe, the price oftallow or the price for jatropha and other plantoils is at least 2.5 times the selling price of diesel(Table 3). Obviously, selling jatropha oil for soapmaking is far more pro®table in these countriesthan using it as a diesel or kerosene substitute.Indeed, in many countries, the oil would be soldat a loss if it has to compete with diesel and ker-osene (Table 6).

7. Costs and returns from jatropha and itsproducts

Costs are involved at all stages in growing J.curcas and in the manufacture of its various pro-ducts. It may be that much, if not all, of theestablishment and management costs are coveredby the primary purpose of growing the plant,such as to control erosion, to reclaim land or asa live fence. In that case, the prunings and fruitmay be regarded as free raw material, but there

are costs involved in the manufacture and mar-keting of the products. Also, as soon as a ``freeraw material'' has a commercial demand, thegrower usually requires a payment for that ma-terial.

The various operations should be listed andthe cost of each operation recorded. For jatro-pha, this should be sub-divided between: thegrowing and management of the crop; the har-vesting; and the manufacture of the various pro-ducts. In particular, the harvesting and use of thefruit or its various components should be docu-mented. Separating the crop establishment, man-agement, harvesting, transport, productmanufacture, and marketing into di�erent com-ponents will pinpoint the various cost centresand help determine the best management prac-tices and the most pro®table product lines.

The Indian study gave some cost and income®gures [12]. These can be used as an example toillustrate the costs and returns involved in thegrowing of jatropha (from seed) as a commercialfruit crop. The average annual rainfall was about1700 mm and it is expected that the crop wouldbe in full production from year 6. The antici-pated yield per hectare of fruit after 6 years is 7.5air-dry tonnes (6.4 oven dry tonnes [odt]) andthat of wood 4.0 tonnes (3.4 odt). This gives acombined yield of 11.5 air dry tonnes. On aver-age, the 7.5 t of fruit will produce 3.45 t of seed,1.80 t of shells and 2.25 t of coat.

A summary of the growing and harvestingcosts are given in Tables 4(a) and (b). Moredetailed costing is given in the Appendix. Thecumulative cost of establishment and mainten-ance to and including year 6 is an estimated

Table 4a

J. curcas: establishment and tending costs (units: US$ per hec-

tare)a

Year Labour Fertilizer Seed Plough hire Total

1±5 [sum] 55 153 3 9 220

6 and onwards 21 102 0 0 123

Total 1±6 76 255 3 9 343

a Source: [12] and author's estimates. More details are given

in the Appendix.

Table 3

The price of mineral oils, tallow and plant oils (Units: US

cents per litre)a

Product Indiab Nepalb Zimbabwec

Kerosene 7.10 15.30 11.37

Diesel 16.57 24.40 25.03

Plant oil/tallow fat 73.60d 80.00e 67.08f

a Source: [12,17,18].b Price in July 1998.c Price in May 1998.d Jatropha oil ex-factory 1992. The ex-factory price of jatro-

pha seed cake was US cents 5/kg. However, to be competitive

with NPK fertilizer today, the ex-factory price has to be

about US cents 3.5/kg and the average delivered price to the

farmer US cents 4/kg.e Palm oil.f Tallow oil.


$343/ha of which $76 is for labour and $255 forfertilizer with the remaining $12 for plough hire,tools and seeds etc. From year 6, the annualmaintenance cost is $123/ha of which $102 is forfertilizer and $21 for labour.

From year 6 and onwards, the labour cost ofharvesting 7.5 t of fruit and extracting the seed is$48/ha and that for cutting and preparing 4 t ofwood for fuel and poles is $20/ha, giving a totalharvesting cost of $68/ha. It is anticipated thatthe coat of the fruit can be sold at $16 per tonne,the shell at $25/t and the seed at $117/t. This lat-ter price is assuming the extracted plant oil isused for soap making. This gives an average sell-ing price, in terms of the whole fruit, of $65/t(air dry). Similarly, the ex-farm price of fuelwoodis $25/t (air dry). The anticipated income per hec-tare is given in Table 5. From the sixth year

onwards, the gross income would be $585 andthe net income $394/ha/y. (If only the seed issold then the net income is reduced to $233/ha).The net return to the farmer, assuming that s/heprovides the labour input would be $480/ha/y.The return on invested capital is more than100%. No rent has been included in the abovecosts, but if a ®gure of $100/ha is assumed, thenthe return is reduced to about 40%. This mayseem high, but in reality, it is just over $1 perday from year 6 onwards for a one hectare farm,if rent is included.4

These ®gures give an idea of the pro®tabilityof jatropha grown as a commercial fruit crop ina high rainfall area with a favourable market forthe products, especially the oil. In regions withlower rainfall yields will be less. For example, ifthe average annual rainfall is 500 mm per year,the above ground net primary production may beof the order of about 6 air-dry tonne per year.But costs would fall more or less proportionatelywith potential production, because the fertilizerdemand would also decrease. If little or no fertili-zer is added, then fruit production would be rela-

Table 4b

J. curcas: harvesting costs of fruit and wood (units: US$ per hectare)a

Year Fruit yield and cost/ha Wood yield and cost/ha

Wt (t) Collect De-coat Shell Total Wt (t) Fell etc. Total cost (3)

1±5 [sum] (9.25) 21 21 17 59 (0.0) 0 59

6 and onwards (7.50) 17 17 14 48 (4.0) 20 68

1±6 (16.75) 38 38 31 107 (4.0) 20 127

a Source: [12] and author's estimates. More details are given in the Appendix. Fruit: per air dry tonne. Collection and transport

$2.30. Removing the fruit coat $2.30. Shelling $1.84. In terms of the cost per tonne of seed, (Table 6). Collection $5. Coat removal

$5. Shelling $4. Wood: thinning, felling, pruning, trimming, cross cutting, hauling and stacking $5/air-dry t wood. An estimated

95% of the above costs are labour costs and 5% are for tools, sacks and equipment.

Table 5

J. curcas: estimated yield and income from the fruit and wood

(units: US$ per hectare ex farm)a

Year Coat Shell Seed Sub-total Wood Total

(price $/t) (16) (25) (117) (25)

1±5 44 56 498 598 0 598

6 onwards 36 45 404 485 100 585

1±6 80 101 902 1083 100 1183

a Source: [12] and author's estimates. Fruit: for the coat and

the shell, the selling price is based on their energy content.

The seed price is based on the buying price at the oil factory.

This factory sells the oil for soap making. The costs of trans-

port and marketing etc. have been deducted to obtain a farm

gate price. The ex-farm selling price of wood is based on its

energy content.

4 If the whole fruit is sold as a fuel, it should command an

ex-farm price of about $33/t. The gross income from year 6

and onwards, from the fruit and the wood would be $348/ha

and the net income $188/ha ($244/ha excluding labour costs).

Thus as a commercial venture, it is marginally pro®table

unless income can be generated from the sale of other pro-

ducts such as honey, tannin (bark/leaves) and medicines

(leaves/fruit). This is why it is important to investigate all

markets and decide on a strategy, before promoting any crop,

plant oil or otherwise.


Table 6

The cost of jatropha oil production and the price of competing productsa

Country India Zimbabwe

Production process Industrial b Hand pressc Motor pressd

Operating days per yeare 250 250 250

Input: t of seed/y 1000f 13.75g 184.2h

Output: t seed cake/yi 730 10.65 141.93

Output: t plant oil/y 270 3.10 42.32

Output: litre plant oil/y 293,500 3,375j 46,000j

Cost of production per litre (US cents)

Seed processing 4.77k 5.70l 5.61l

Seed delivery ex-processing 62.25m 46.04n 45.25n

Oil manufacture 5.87 16.44o 14.59o

Total cost 72.89 68.18 65.45

Selling price of substitute products (US cents per litre)p

Kerosene (para�n) 7.10 11.37 11.37

Diesel 16.57 25.03 25.03

Plant oil/tallow oil 73.60 67.08 67.08

Seed cake (per litre of oil)q 8.71 11.05 10.80

a Source: [12,13,17±19] and author's estimates.b The Indian factory is 50 years old and no machinery cost ®gures are available. The following yearly cost ®gures were given (in

US$): energy 4667; labour (10 people) 2667; depreciation 1000. In addition the following ®gures were assumed: spares 3500; ®lters

880 (0.3 cents/litre); containers 2935 (1 cent/litre); contingencies 10%.c Hand press cost with scales and utensils $426. Depreciated over 10 years ($43 per year). The following yearly costs were

assumed (in US$): replacement parts, 43; plant oil ®lters, 10; containers for plant oil, 34; labour [1 person], 375; contingencies,

10%.d Motor press cost with scales and utensils $5,410. Depreciated over 7 years, ($773 per year). The following yearly costs were

assumed (in US$): replacement parts, 541; plant oil ®lters, 136; containers for plant oil, 460; labour [two persons], 750; diesel [50

litres per day] and lubricating oil, 3442; contingencies, 10%.e Eight-hour day assumed.f Annual input of air-dried whole fruit in t 2174 (coat, 652; nut shell, 522; kernel, 1000).g Annual input of air-dried whole fruit in t 29.89 (coat, 8.97; nut shell, 7.17; kernel, 13.75).h Annual input of air-dried whole fruit in t 400.54 (coat, 120.16; nut shell, 96.13; kernel, 184.25).i The cake could be sold as fertilizer, fuel or in a non-toxic form as animal feed. The value as a fertilizer in India is $50/t ex-fac-

tory.j These are average ®gures. It is possible to increase production of oil by about 10%.k Seed processing costs per tonne of seed are: collection $5, coat removal $5 and shelling $4, total $14. Thus the net farm price is

$103/t of seed or $47/t of fruit.l A ®gure of $14/t for seed processing has been assumed (see 10 above). In addition, bags, transport and commission etc. are esti-

mated to be $40/t seed including $5 for delivery to factory.m The price per tonne of seed is: at the farm $117, at the godown $141, at the market place $187, and delivered to the factory

$197. The collection, de-coating, and shelling are assumed to be $14/t (see 10 above). Thus the net farm price is estimated to be

$103/t of seed or $47/t fruit. Apart from establishment and management costs, each year the farmer has to spend on fertilizers

about $30/t of seed produced to maintain the fertility of the soil. The farmer has other products to o�er. These include about 1.16

t of wood, 520 kg of nutshells and 650 kg of fruit coat per tonne of kernel (seed) produced.n A ®gure of $127/t of seed delivered to the factory is assumed. The ex-farm price is $73/t seed, excluding processing costs [$87

with processing costs]. The selling price of the whole nut is $51/t and that for the whole fruit (¯esh, shell and kernel) is $34/t.o These costs could be lowered by 10±20% through increased productivity and by charging the buyer for the container.p In Nepal (July, 1998), the price in US cents per litre is: kerosene 15.5; and diesel 24.4.q The total income ex factory is the sum of the income from the oil and the seed cake, assuming a cake selling price of $35/t.


tively low and there would be more woody bio-mass production. This may be desirable for hed-ging purposes, but expectations of good fruityields should be discounted. If the only marketfor the oil is as a diesel substitute, then it uneco-nomic to grow the plant for this end-use(Table 6). Both the farmer and the oil producerwould make a loss!

Table 6 gives the costs of production for threedi�erent methods of oil manufacture in twocountries. The Indian example has the lowestcost components, with the Zimbabwe hand pressshowing the highest costs. However, what allthese manufacturing processes indicate, is thatthe present cost of producing oil from the jatro-pha plant, assuming that the grower, processor,transporter etc. receive adequate returns for theire�orts, is much more than the selling price ofdiesel and kerosene.

Of course, the seed cake has a value and thiswill improve the pro®tability of the oil millingbusiness. But the income from one productshould not be used to subsidize that of anotherproduct. In other words, the plant oil should notbe sold for diesel (or kerosene) if there is a morepro®table market for the oil, as there is in thecase of the examples given in Table 6. The excessincome earned from the sale of the plant oil plusseed cake could be used to purchase diesel etc.,rather than subsidizing the purchasers of oil soldas a diesel substitute. This latter policy will leavethe grower and oil manufacturer worse o� anddiscourage pro®table rural industries such assoap making.

8. Discussion

J. curcas is a versatile plant with several actualand potential uses. The oil from the seed of theplant is potentially the most valuable end pro-duct. However, for some projects ®nanced bydonors, NGOs and/or governments, too muchemphasis has been placed on using the oil as adiesel or kerosene substitute. At present, thisappears to be a sub-optimal solution, for its priceas a diesel substitute is much less than for otheruses and the technology has not been fully

proved. Assuming a fair return to the growers,fruit processors, transporters, traders and oilmanufacturers, the growing and production costsfor the oil are three to ten times the selling priceof diesel and kerosene in most developingcountries. Thus, it cannot compete with hydro-carbon fuels, unless donors, the state or thegrowers/producers subsidize the plant oil. Ofcourse, the various cost components could beexaggerated and the oil recovery percentageunderestimated, but this does not invalidate theargument that other potential end-uses are morepro®table.

In many countries, the oil could be used forsoap making and in most cases it should be apro®table venture. Soap making can be and isundertaken in rural areas by small-scale entrepre-neurs; this appears to be the market to aim for atpresent. In addition, the oil cake can be used asa fertilizer or fuel. Heat is required in the oilextraction process and the shells and the fruitcoat could supply this, with the ash being sold asa fertilizer. The entrepreneurs could then usesome of the pro®ts to buy diesel to run otherventures!

A potential problem is the availability of suit-able presses for jatropha oil. Sun¯ower seedpresses have been used, but these are not comple-tely satisfactory and technical problems are ex-perienced as well as below optimum recovery ofoil.

It is possible to detoxify seed cake, but cur-rently, it does not appear to be cost e�ective.There are varieties of non-toxic jatropha nutsthat may produce edible oil suitable for humanconsumption and seed cake appropriate for ani-mal feed. These varieties are available in Mexicoand being tested in some countries at present. Ifthey are successful, then a lucrative market couldopen up for edible oil and cake with a price simi-lar to sun¯ower oil. However, jatropha wouldloose its advantage as a hedging plant.

In addition, several parts of the jatrophaplant have medical and cosmetic uses. The econ-omics of making such products should be inves-tigated and the markets for the productsresearched. Again, such products may turn outto be more pro®table than using jatropha for


fuel. All non-energy uses of the products fromJ. curcas should be tabulated to provide a rangeof options.

Jatropha is also an excellent hedging plant andit should be cost competitive with a traditionalpost and wire fence. If Jatropha is to be grownas a commercial crop, especially for fruit pro-duction, the addition of fertilizer is a necessity.The seed cake could be applied to the plantationand/or nitrogen-®xing trees grown in combi-nation with jatropha. Unless this is done, seedproduction will diminish as the land becomes

exhausted. The various management techniquesshould be recorded and gaps ®lled where knowl-edge is missing. This is essential if this plant is tobe accepted by farmers.

In order to re-stimulate the interest in jatro-pha, the emphasis should be adjusted and movedaway from its use as a diesel substitute or as ahousehold cooking and illumination fuel. Thefocus should be switched to examining all theattributes of the plant within various land usesystems and to develop and expand the mostpro®table uses of its many products.

Appendix

A.1. Establishment costs J. curcas for commercial production (units: $ per hectare)a

Operation Labour Materials/machines Total Remarks

Ploughing 0.8 9.0 11.8 Animal drawn ploughDigging pit 6.5 0.0 6.5 1600 pits per haApplying FYM (Farmyard manure) 1.5 7.5 9.0 1 kg per holeSeeding 0.5 2.8 3.3 two seeds per holeFilling pit 3.3 0.0 3.3Weeding 6.5 0.0 6.5Applying fertilizer 1.1 20.5 21.6 160 kg NPK, two dressingsYear 1. Initial Establishment 22.2 39.8 62.0Year 2. Weeding 6.5 0.0 6.5Applying fertilizer 1.4 6.9 8.3 170 kg seed cakeTotal year 2 7.9 6.9 14.8Year 3. Applying fert. 3.5 16.9 20.4 420 kg seed cakeYear 4. Applying fert. 7.1 33.9 41.9 840 kg seed cakeYear 5. Applying fert. 14.1 67.7 81.8 1680 kg seed cakeYear 6 and onwards. Applying fertilizer 21.2 101.6 122.8 2520 kg seed cake

a Labour wage $1 per day. Cost of seed cake ex-factory $35/t. Transport to farm $5/t. Handling $0.3/t. Spreading $8.4/t. 1 tonne

of seed cake is equivalent to 150 kg. NPK (40:20:10).


A.2. Harvesting cost jatropha fruit and wood (Units: $ per hectare)b

Yield/ha (tonnes) Collect Remove coat Shell Total

FruitYear 2 (0.50) 1.15 1.15 0.92 3.22Year 3 (1.25) 2.87 2.87 2.31 8.05Year 4 (2.50) 5.75 5.75 4.60 16.10Year 5 (5.00) 11.50 11.50 9.20 32.20Year 6 (7.50) and onwards 17.25 17.25 13.80 48.30Wood Fell/Prune Cross cut Cart/StackYear 6 (4.00) and onwards 6.25 6.25 7.50 20.00Total Year 6. Fruit and wood 23.50 23.50 21.30 68.30

a Labour cost $1 per day. Labour 95% of above costs, tools/sacks etc. 5%. Twelve adapted and author's estimates.

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a review of jatropha curcas: an oil plant of unfulfilled promise

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