Biomass and Bioenergy 19 (2000) 1±15
www.elsevier.com/locate/biombioe
A review of Jatropha curcas: an oil plant of unful®lled
promise 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 that
can 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. The
establishment, management and productivity of jatropha under various climatic conditions are not fully
documented. 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 similar
properties to palm oil. The costs and returns of growing the plant and producing the plant oil are discussed and
tabulated. 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 is
examined and found not viable. Oil for soap making is the most pro®table use. It is concluded that all markets for
jatropha products should be investigated. If the full potential of the plant is to be realized, much more research is
required 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
There 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 similar conclusions made in this article.
p
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 erosion, to reclaim land, grown as a live fence, especially 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
0961-9534/00/$ - see front matter 7 2000 Elsevier Science Ltd. All rights reserved.
PII: S 0 9 6 1 - 9 5 3 4 ( 0 0 ) 0 0 0 1 9 - 2
2
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
has few pests and diseases and will grow under a
wide range of rainfall regimes from 200 to over
1500 mm per annum. In low rainfall areas and in
prolonged rainless periods, the plant sheds its
leaves as a counter to drought.
Jatropha is easy to establish, grows relatively
quickly and is hardy, being drought tolerant. It is
not browsed, for its leaves and stems are toxic to
animals, but after treatment, the seeds or seed
cake could be used as an animal feed. Various
parts of the plant are of medicinal value, its bark
contains tannin, the ¯owers attract bees and thus
the plant has a honey production potential; its
wood and fruit can be used for numerous purposes including fuel. Of particular importance,
the fruit of jatropha contain viscous oil that can
be used for soap making, in the cosmetics industry and as a diesel/kerosene substitute or extender. This latter use may be of importance when
examining practical substitutes for fossil fuels to
counter greenhouse gas accumulation. Also, like
all trees, it ®xes atmospheric carbon, stores it in
wood and assists in the build up of soil carbon.
However, for several reasons, both technical
and economic, the full potential of jatropha is far
from being realized. The growing and management is poorly documented and there is little experience in marketing its products. Thus,
frequently, growers do not achieve the optimum
output of products, such as the fruit that would
bring the greatest rewards. Neither do they have
much information about the most lucrative markets. In many instances, markets have not been
explored or properly quanti®ed, nor have the
costs or returns been assessed to supply the
di€erent products to these markets. Therefore,
actual or potential growers, especially in the subsistence sector, may be reluctant to invest time
and money in a crop that only has promise
rather than concrete rewards.
Some of the current strategies used to promote
jatropha may be sub optimal and could act as a
deterrent instead of a stimulus in promoting
rural development. Thus, it is timely to examine
problems encountered in the growing and use of
jatropha, achievements to date and the present
strategy in promoting this potentially useful and
versatile plant.
2. Present strategies for promoting J. curcas
Jatropha is widely grown in Mexico, Nicaragua, N.E. Thailand and in parts of India. It is
now being promoted in southern Africa, Brazil,
Mali and Nepal. There are several governments,
international organizations, national bodies and
NGOs promoting the planting and use of J. curcas and other oil bearing plants. These include
the World Bank, the International Plant Genetic
Research Institute, Austrian and German Technical Assistance Programmes, the Rockefeller
Foundation, Appropriate Technology International and Intermediate Technology Development Group Ð (USA and UK based NGOs)
and the Biomass Users Network (BUN) and
Plant Oil Producers Association of Zimbabwe
[1±8].
Two principal objectives of these initiatives are
to use oil plants and their products for economic
and environmentally sustainable rural development and to make rural areas self sucient in
energy, especially liquid fuels. Where possible,
this is to be achieved without displacing other
agricultural crops or competing for land that has
a higher opportunity in other applications. J. curcas was chosen as one of the prime plant oil
species, especially for Brazil, Nepal and Zimbabwe. Areas in these three counties, that already
were growing such species, were chosen as demonstration sites for the utilization of plant oil
with appropriate technology. In order to achieve
the stated objectives various goals were formulated. These goals can be summarized as follows:
. To promote the use of plant oil as a fuel in
stationary or mobile engines for water pumping (irrigation), grain milling, transportation
and electrical generation.
. To encourage the use of plant oil as a viable
renewable energy option for cooking, lighting
and heating.
. To reduce poverty, especially that of women,
by stimulating economic activities in rural
areas by using the products of such plants for
the manufacture of soap, medicines, lubricants,
chemicals, fertilizers, insecticides.
. To improve the environment through land rec-
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
lamation, erosion control, enhanced soil fertility, a better microclimate and greenhouse gas
(GHG) mitigation.
The successful implementation of these goals
should lead to:. An improved quality of life for rural people.
. A reduced consumption of ®rewood and residues in rural areas.
. An increase in the gross domestic product
(GDP).
. A reduction of expenditure of imported fuels
for rural consumption.
. A decrease in the deforestation rate.
. A more productive use of land.
. Expanded options for carbon dioxide abatement.
. The establishment of decentralized technology
chains based on the use of plant oil.
. The promotion of South-based new technology
development.
While the overall objectives are laudable and are
the aim of most governments, NGOs and donor
agencies, the goals to accomplish these objectives
may be contradictory. Several agencies are promoting jatropha oil as an energy source, to the
detriment of other uses and other plant products,
without fully analyzing the economics of growing
and producing the oil, its technical appropriateness and the cost of substitute fuels. Using plant
oil for motive power and cooking may lead to
the growers and producers subsidizing the end
users and forgoing pro®table markets for the oil
and/or other product. Thus, promoting plant oil
for these uses may deter sustained economic
growth, hinder improvements to the quality of
life and delay poverty alleviation.
The oil from jatropha is an important product
from the plant, but it is only one of a number of
products. Too much emphasis seems to have
been placed on the use of this oil for motive
power. There are still teething problems with the
use of jatropha oil in diesel engines1 and it is
1
Numerous engines have been ®eld tested with jatropha oil.
Performance tends to decline over time and maintenance is
the critical factor [10].
3
very doubtful if the plant oil can compete with
diesel fuel at its current price, even if a ``carbon
tax'' is imposed on fossil fuels. Thus, at present,
there are technical constraints and economic factors against using jatropha and other plant oils
for motive power. These should be fully considered and compared to alternative uses of the
oil, rather than pursuing what may be sub-optimal solutions.
Sooner or later, as (fossil fuel) oil reserves
diminish and/or a substantial carbon tax is
imposed worldwide on fossil fuels, carbon based
liquid fuels from biomass will become universally
competitive. Meanwhile, countries have to gain
experience in the growing and use of versatile
plants such as jatropha so that they will be in a
position to capitalize on this knowledge once the
oil becomes competitive with diesel etc. This may
be achieved by looking at other uses for the
jatropha plant and its products.
Another goal cited above which should be
reexamined is the use of plant oil for household
cooking in rural areas to substitute for fuelwood.
The cost of producing plant oil is usually much
more than the cost of kerosene (or purchased
fuelwood). Yet rural people use kerosene sparingly for lighting, but rarely for cooking. Even if
plant oil can be produced at a comparable price
to kerosene, rural people are most reluctant to
pay for cooking fuel, be it plant oil, wood or kerosene etc., if any form of biomass can be collected. If fuelwood is scarce, rural people burn
crop residues and dung.
One of the above goals is to use jatropha oil
for cooking in rural areas in order to curtail
deforestation. However, the use of fuelwood for
rural cooking causes little if any deforestation,
although it may cause some woodland degradation [9]. By far the largest cause of deforestation is clearing land for agriculture in response to
population increase. In order to slow down
deforestation, apart from more e€ective family
planning initiatives, agricultural productivity has
to increase. J. curcas could play a role through
land reclamation, erosion control, protection and
improving the microclimate.
Jatropha can be used to reclaim eroded land
and other problematical sites. Jatropha hedges
4
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
and shelterbelts can assist other crops on all
land types by keeping out animals, improving
the microclimate and providing humus to the
soil. It could also be promoted as a commercially viable crop on medium to high potential
areas. Thus, such plants should be regarded as
being complimentary to agricultural crops
rather than competing with them. Several commercial crops may lend themselves to jatropha
fencing or shelterbelts. These include co€ee,
market gardening, ranching, tobacco farming
etc. Such valuable crops then can be grown
without damage from browsing animals while
at the same time marketable goods may be
produced from the hedge itself.
Also, jatropha could be used as a substitute
for wire fencing and posts round ®elds, as
well as along roadsides and railway tracks. In
Mali, the principal reason for planting jatropha is as a hedging plant. A comparison
between the two types of fencing may show
that live fencing is much more cost-e€ective
than wire fencing. Current experience should
be documented and potential sites listed by
rainfall, soil type and present use. Jatropha
should not be con®ned to problematical sites,
but used on all areas where it can complement
other farming systems or where it has a comparative advantage.
The jatropha plant has few insect or fungal
pests and is not a host to many diseases that
attack agricultural crops. It is reported that, in
some areas of Zimbabwe, the golden ¯ee beetle (Podagrica spp) can harm jatropha and
that it plays host to the ``frog eye'' fungus
(Cercospera spp), common in tobacco [11].
How serious such pests are could be investigated and recommendations made, if any, on
containment of such threats. This may preclude jatropha being used as fencing in
tobacco areas.
Using the seed cake as a fertilizer is being promoted as an income-generating activity for the
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.
oil processor. The products from the fruit Ð the
exocarp (coat), shell and processed seed cake Ð
are rich in nitrogen, phosphorous and potassium
(NPK) and/or can be used as soil improvers.
Thus, the seed cake when added to the soil can
increase agricultural productivity, while at the
same time save foreign exchange by replacing
mineral fertilizers. However, jatropha is not a
nitrogen ®xing species and to maintain its productivity, fertilizers will have to be added to the
soil. One publication recommends that the seed
cake be returned to the jatropha sites to maintain
fertility [12]. Thus, the farmer may have to buy
back the cake and/or use other fertilizers. A
more pro®table use for the cake could be as animal feed, if non-toxic varieties can be grown,2 or
the 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 alternatives should be listed, without prejudice. Management practices, specifying di€erent options,
should be tabulated and all the actual or potential markets researched, together with income
and expenditure information. This should allow
governments, donors, NGOs and above all, potential growers to make informed decisions. In
the past, expectations have been built up about
plant oil, some of which have turned out to be
unfounded or inappropriate. There are still misconceptions and gaps in the knowledge about the
economics, management and markets of jatropha
and its products. These will now be discussed.
3. Management of J. curcas
Partial information is available about the silviculture and management of jatropha. It is known
that jatropha can be established from seed, seedlings and cuttings. Plants from seeds develop a
taproot and four lateral roots, whereas it has
been reported that cuttings do not develop a taproot [2]. The best time for planting is in the
warm season before or at the onset of the rains.
In the former case, watering of the plants is
required.
The recommended spacing for hedgerows or
soil conservation is 15±25 cm. apart (within and
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
between rows) in one or two rows and 2±3 m by
1.5±3 m for plantations [6]. Thus there will be
between 4000±6700 plants per kilometre for a
single hedgerow and double that when two rows
are planted. The number of trees per hectare at
planting may range from 1100 to 3300. Wider
spacing is reported to give larger yields of fruit,
at least in early years [2]. Further information is
required on to the planting practices, management and the spacing employed, but one booklet
has been produced on management practices in
Gujarat, Maharashtra and Rajasthan states of
India [12].
Growth of the plants is dependent on soil fertility and rainfall, especially the latter. Flower and
seed production respond to rainfall and nutrients.
A poor nutrient level will lead to increased failure of seed development [1]. Thus, it is important
to maintain soil fertility; this is contrary to statements made in some publications [13]. With one
rainy season per year, there will be only one
annual fruiting; for irrigated crops, up to three
fruitings can occur each year.
Woody biomass growth is not recorded in any
publication to hand, unlike seed production.
Seed production ranges from about 0.4 to over
12 t/ha/y, after ®ve years of growth [6].3 This
range in production must be from low to high
precipitation. In Mali, where jatropha is planted
in hedges, the reported productivity is from 0.8
to 1.0 kg of seed per metre of live fence [3]. This
is equivalent to between 2.5 and 3.5 t/ha/y. It is
assumed that these yields are of air dry tonnes
per hectare, with an average whole nut moisture
content of about 10% (wet basis). There should
be a systematic study done on the yields of jatropha fruit and its components, especially the nut,
and wood etc. by annual rainfall. The number of
rainy seasons per year and the nutrient level of
the soil are two possible variables. Such infor3
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.
5
mation is necessary in order to give the growers
and the users of the products an idea of the
expected yields and returns on investment.
Provided the nutrient level is sucient, plant
growth is a function of water availability, especially in the tropics. Net primary production
(NPP), which is the production of all types of
plant biomass, be it annuals, tree leaves, woody
biomass and fruit etc., ranges from an average of
1 t/ha/y of above ground oven dry matter, (1.2 t
air-dry) with an annual rainfall of 200 mm, to an
average of 10 t/ha/y. (11.8 t air-dry) with a rainfall of 1500 mm [14,15].
If management favours fruit production
through the application of fertilizers, about onequarter each of the NPP in J. curcas may be in
the form of woody biomass, and leaves, with the
remaining half being fruit, but of course, this
should be tested. Plant growth, especially wood,
is a function of age and rainfall as well as management practices. It is reported that jatropha
trees/bushes live up to 50 years and reach a
height of 5 m. Like all perennial plants, it displays vigorous growth in youth; this will tail o€
gradually towards maturity. Good sivicultural
practice requires that hedges are trimmed and
plantations are pruned or even thinned. Normally, if say 1600 seedlings were planted per hectare, these would be thinned frequently, until
about 400±500 trees remain at maturity. To
retain a high density, the plants would have to be
pruned annually and thinned periodically. Similarly, hedges require trimming in order to contain
them and to reduce competition.
Documentation is sparse on the management
of jatropha hedges and plantations. Already, the
growers must be practising some form of management. These practices could be recorded and
the best ones highlighted, as should be the
growth ®gures. The growth and yield of wood
may be in proportion to nut yield, but some
management practices may a€ect yields of nuts
and/or wood. The wood may be just as useful as
the fruit: thus obtaining optimum yields of all
products may be the desired goal.
In Zimbabwe, the Agricultural Research Trust
(ART) has laid down trials of di€erent provenances of J. curcas. Such research work is vital
6
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
in determining the most appropriate provenances
and the optimum management systems for this
country: it must be encouraged. The current status of this work may give an important insight
into the management and yield of jatropha in
Zimbabwe. Non-toxic varieties of J. curcas from
Mexico were sent to Zimbabwe for planting [1,
p. 203]. It may be that ART has these varieties in
their provenance trials. If successful, the nut and/
or the seed cake could be used as animal feed
without being detoxi®ed. If so, a cost comparison
should be made between using the cake as an
animal feed or returning it to the soil to maintain
fertility.
In Zimbabwe, the seed cake is being promoted
as 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]. One
tonne of seedcake applied to the soil is equivalent
to applying 0.15 t of NPK [40:20:10] mineral fertilizer. The seed cake, being relatively rich in
nitrogen, implies that jatropha requires a nitrogen rich soil to obtain a good seed production.
This is because J. curcas is not a nitrogen ®xing
plant. There are no reports of root associations
with (nitrogen ®xing) rhizobium, although if
phosphorous is scarce, mycorrhiza may be found
on the root system assisting with the uptake of P
[6]. If nitrogen is not applied, then ¯owers may
abort and seed production decline [2]. An Indian
booklet on the management of jatropha recommends the addition of farmyard manure and
NPK to the planting hole and yearly top dressings of fertilizers including the seed cake [12].
There is little published information about the
fertilizer requirements of jatropha. Many documents assume that it is a plant with low fertilizer
requirements, but this is contrary to output
requirements. The subsistence sector may not be
able to a€ord mineral fertilizers, and/or the distribution system may be poor. Growing jatropha
in combination with nitrogen ®xing plants, especially nitrogen ®xing trees, may be the most
cost±e€ective solution. There are many agro-forestry trees which grow under variable climatic
conditions, ranging from Prosopis spp in low
rainfall areas, to Sesbania spp and Leucaena spp
with rainfall above 1,000 mm. Investigations on
the fertilizer and soil pH requirements of jatropha should be a part of a detailed study into the
management of J. curcas, if the promotion of
this versatile plant is to have lasting success.
Considerable information is still required
about management systems and nutrient requirements of J. curcas. Production levels by rainfall
and over time of both wood and fruit, especially
the nut, are important if people are to be encouraged to plant and manage jatropha as a pro®table crop. The use of jatropha by itself or in
combination with other plants to improve the environment or to sustain the land use system
should be documented so that a comprehensive
picture is built up about growing the plant under
di€erent climatic and management conditions.
4. J. curcas as an energy source
The oil from jatropha is regarded as a potential fuel substitute. Diesel is a hydrocarbon with
8±10 carbon atoms per molecule, but jatropha oil
has 16±18. Thus, the nut oil is much more viscous than diesel and has a lower ignition quality
(cetane number). For these reasons, using the oil
directly in engines has not been fully tested over
long periods. In Europe, plant oils are usually
trans-esterised (with alcohol and hydroxide) to
bio-diesels with properties similar to mineral diesel. This reduces their viscosity and increases
their cetane number. However, this requires considerable investment and currently it is not coste€ective. Experiments have also been undertaken
in Nicaragua.
A principal reason is that the price of crude
has been dropping in relative terms over the last
decade. At present, jatropha oil is not cost competitive with diesel, except in exceptional circumstances. Therefore, it is as well to re-examine the
use of the di€erent products from the jatropha
plant to determine if any are pro®table sources
of energy.
The types of fuels which can be obtained
directly from the jatropha plant are wood, the
whole fruit and parts of the fruit burnt separately
or in combination, namely the exocarp (coat),
the nut shell and the kernel (or seed). After pro-
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
cessing, in which energy inputs are required,
other fuel products can be made from the plant
such as plant oil, seed cake and charcoal (from
the wood or nutshell). All these products have
di€erent energy values and production costs.
Table 1 gives the energy values of the various
fuels and Table 2 lists the possible end uses of
these fuels together with other potential uses.
Processing increases the energy value of the
product, but the overall energy availability
decreases unless a use can be found for the byproducts. This is an important point that cannot
be over-emphasized. Removing the coat from the
fruit increases its energy value by 20%, from
about 21 to 25.5 MJ/kg. But if the coat is discarded, then there is an overall loss in energy of
about 15%, because the whole nut is only 70%
of the weight of the air-dry fruit. It may be that
7
the price commanded by the whole nut more
than o€sets the loss of energy in the discarded
coat, or a pro®table use can be found for the
coat. For example, it could be burnt in the
household or at the processing factory or used
for non-energy purposes such as a soil conditioner. In such cases, the latter value has to be
included in the overall pro®tability statement. In
each situation, markets should be explored for all
products and by-products and the most bene®cial
line of action pursued.
In terms of unit weight, the kernel (seed)
has 40% more energy than the whole fruit
and jatropha oil nearly twice the energy value.
But overall, the kernel has about 35% less
energy and the oil about 70% less energy that
the 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
(%)b
Moisture content
(%)c
Energy value
(MJ/kg)d
Woodf
Whole fruitg
Whole nut
Coat
Shell
Kernel
Wood charcoal
Shell charcoal
Plant oilh
Seed cakeh
1
6
4
13
5
3
3
15
< 0.1
4
15
8
5
15
10
3
5
5
0
3
15.5
21.2
25.5
11.1
17.2
29.8
30.0i
26.3i
40.7j
25.1k
a
Coat
Shell
Kernel
30
0
100
0
0
24
34
0
100
0
46
66
0
0
100
Recovery percentagee
95±100
95±100
67±70
28±30
23±24
44±46
15±25
15±25l
11±18 [23±38]m
29±35 [62±77]m
Source: [1,16].
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.
b
8
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
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 products and by-products that should be the primary consideration, or at least the net income
plus an implied value for non-monetary products.
Apart from household cooking, potential markets 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 survey should be done, by region or district, of
actual and potential markets for the products of
jatropha. Markets have to be researched and the
quantities required by each end use recorded
along with the price of substitute products. It
must be remembered that the growing and processing of jatropha products are but two stages
in the marketing process. Usually, there are other
costs involved such as storage, transport and
marketing plus pro®t margins. All these elements
have to be considered when determining pro®table end uses.
Bulk demand for the products of jatropha,
such as the oil for industrial soap making depend
on a constant and year round supply of raw material. Thus, even though supplying plant oil to
this 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
Bean sticks, planting and fencing material
Large branches
and stems
F&S
Whole fruit
F&S
Whole nut
F&S
Exocarp (coat)
Shell
F
F&S
Kernel
F&S
Wood charcoal
Shell charcoal
Plant oil
S
S
S
Seed cake
F&S
Rural household (H/h) cooking. (May be
dicult to burn because remains green for
long period)
Rural & Urban H/h cooking. Service sector
and industrial use Ð tobacco barns, brick
stacks, boiler fuel, cooking in schools etc.
Rural & Urban H/h cooking. Service and
industrial uses Ð tobacco, brick, bakeries,
boilers, schools etc.
Rural & Urban H/h cooking. Service and
industrial uses Ð tobacco, brick, bakeries,
boilers, schools etc.
Rural H/h cooking
Rural H/h cooking, industrial use Ð
tobacco, brick, boilers, etc.
Rural H/h cooking, industrial use Ð
tobacco, brick, boilers, etc.
Urban H/h & non-H/h cooking
Urban H/h & non-H/h cooking
Urban cooking, urban and rural lighting,
service sector and industrial uses, diesel and
kerosene substitute or extender
Urban H/h & non-H/h cooking, boiler fuel
a
Source [1] and author's estimates.
Building poles, fence posts, charcoal
production
Ash used as a fertilizer
Ash used as a fertilizer
Soil improver
Soil improver, charcoal production
Animal feed (if treated) planting material
Fine as soil conditioner
Activated charcoal
Soap making, lubrication oil, cosmetics,
medicine, cooking oil (detoxi®ed)
Fertilizer, animal feed (if treated)
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
involved could be beyond the present capacity of
the growers. Surveys should be undertaken on
the estimated output of products, by region.
Plans can then be drawn up to meet the demands
of particular industries, if pro®table.
Possible end uses for jatropha products are
given in Table 2. These are divided into energy
and non-energy uses. This list may not cover all
uses and there may be speci®c uses in particular
districts or countries. It is given as a guide when
trying to assess the market potential of the various products from jatropha.
Several donor projects have concentrated on
the production of jatropha oil as a diesel substitute for engines and/or as a kerosene substitute
for cooking and lighting. In many developing
countries, diesel fuel is taxed less than petrol
(gasoline) and kerosene has little if any tax;
sometimes it is subsidized. Table 6 demonstrates
that at present jatropha oil is about three times
more expensive than hydrocarbon fuels. Thus, as
a general rule, the present day costs of diesel and
kerosene do not make it attractive to produce
plant oil as a substitute for these petroleumbased fuels.
Only where diesel and kerosene are scarce, due
to poor and intermittent distribution systems
and/or smuggling the fuel to other countries
occurs, could it be cost e€ective to produce plant
oil as a diesel substitute. Also, kerosene may be
scarce because it is used as a diesel substitute or
the price is in¯ated because rural people buy
small quantities at a time. In these cases it may
be pro®table to use plant oil as an illumination
(not cooking) fuel in rural areas. But it is unlikely that there will be a market for such fuel in
urban areas. Detailed studies should be carried
out of the availability and delivered price of diesel and kerosene to the various locations where
plant oil is grown to determine if this oil can
compete with these fossil fuels.
In Zimbabwe, it is proposed to generate electricity with plant oil in one project and to pump
water for irrigation in another project. An economic feasibility study was undertaken on these
two projects which showed they were marginal at
best [13]. No alternative analysis was done with
diesel as the fuel, but this should have been
9
undertaken for comparative purposes. Marginally
economic projects may be justi®ed on social
grounds, but still they should use the cheapest
fuel source etc. Just because a potential fuel is
produced in the vicinity is no reason for its use if
there are cheaper alternatives. Besides, jatropha
oil and other products may have more pro®table
(non-fuel) uses, some of which are listed in
Table 2. This will now be elaborated.
6. Non-fuel uses of J. curcas
Jatropha is a woody plant and, therefore, its
twigs, branches and stems can be used for a
number of purposes, especially as fuel, sticks and
poles. Unfortunately, the twigs remain green for
a long time and are dicult to dry out and thus
burn. If used as poles, they have a tendency to
sprout. However, in some countries, the live pole
is used to support vines such as the vanillin
plant. It ¯owers profusely in response to rainfall
or irrigation and can ¯ower up to three times a
year. Bees pollinate these ¯owers; thus it is possible to have apiaries in association with jatropha
areas. The fruit is normally toxic, unless treated,
but there are varieties that produce non-toxic
fruit. If it can be detoxi®ed cheaply, or the oil
extracted from toxic free varieties, it could be
used in food preparation and the seed cake used
as animal feed. Latex and oil from the plant have
medicinal, pesticidal and mollusk control properties. Tannin can be extracted from the bark and
nutshell etc. and used to treat leather. A varnish
can be made from the oil and the leaves are a
feedstock for silk worms.
For those districts, regions and countries that
do not produce palm or similar oils, the most
lucrative non-food product could be the plant
oil. Jatropha oil is similar to sun¯ower/palm oils
and tallow (animal fat). It contains a fatty acid
and one of its uses is as a raw material for soap
making. Jatropha oil has been used commercially
for soap manufacture for decades, both by large
and small industrial producers. For example, in
India it is used by a large industry (Hindustan
Lever). In Zimbabwe, soap is produced by small
informal industries in rural areas using plant oil,
10
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
but one large manufacturer is interested in using
jatropha oil as a substitute for tallow. However,
the monthly requirement of this industry alone is
2000 litres of oil. To supply this demand, would
require the equivalent of about 20,000 ha.
Clearly, the present area, an estimated 2000 ha
equivalent, is only about 10% of the required
area to meet this demand alone.
In India, Nepal and Zimbabwe, the price of
tallow or the price for jatropha and other plant
oils is at least 2.5 times the selling price of diesel
(Table 3). Obviously, selling jatropha oil for soap
making is far more pro®table in these countries
than using it as a diesel or kerosene substitute.
Indeed, in many countries, the oil would be sold
at a loss if it has to compete with diesel and kerosene (Table 6).
7. Costs and returns from jatropha and its
products
Costs are involved at all stages in growing J.
curcas and in the manufacture of its various products. It may be that much, if not all, of the
establishment and management costs are covered
by the primary purpose of growing the plant,
such as to control erosion, to reclaim land or as
a live fence. In that case, the prunings and fruit
may be regarded as free raw material, but there
Table 3
The price of mineral oils, tallow and plant oils (Units: US
cents per litre)a
Product
Indiab
Nepalb
Zimbabwec
Kerosene
Diesel
Plant oil/tallow fat
7.10
16.57
73.60d
15.30
24.40
80.00e
11.37
25.03
67.08f
a
Source: [12,17,18].
Price in July 1998.
c
Price in May 1998.
d
Jatropha oil ex-factory 1992. The ex-factory price of jatropha 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.
b
are costs involved in the manufacture and marketing of the products. Also, as soon as a ``free
raw material'' has a commercial demand, the
grower usually requires a payment for that material.
The various operations should be listed and
the cost of each operation recorded. For jatropha, this should be sub-divided between: the
growing and management of the crop; the harvesting; and the manufacture of the various products. In particular, the harvesting and use of the
fruit or its various components should be documented. Separating the crop establishment, management,
harvesting,
transport,
product
manufacture, and marketing into di€erent components will pinpoint the various cost centres
and help determine the best management practices and the most pro®table product lines.
The Indian study gave some cost and income
®gures [12]. These can be used as an example to
illustrate the costs and returns involved in the
growing of jatropha (from seed) as a commercial
fruit crop. The average annual rainfall was about
1700 mm and it is expected that the crop would
be in full production from year 6. The anticipated yield per hectare of fruit after 6 years is 7.5
air-dry tonnes (6.4 oven dry tonnes [odt]) and
that of wood 4.0 tonnes (3.4 odt). This gives a
combined yield of 11.5 air dry tonnes. On average, 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 harvesting
costs are given in Tables 4(a) and (b). More
detailed costing is given in the Appendix. The
cumulative cost of establishment and maintenance to and including year 6 is an estimated
Table 4a
J. curcas: establishment and tending costs (units: US$ per hectare)a
Year
Labour Fertilizer Seed Plough hire Total
1±5 [sum]
55
6 and onwards 21
Total 1±6
76
153
102
255
3
0
3
9
0
9
220
123
343
a
Source: [12] and author's estimates. More details are given
in the Appendix.
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
11
Table 4b
J. curcas: harvesting costs of fruit and wood (units: US$ per hectare)a
Year
Fruit yield and cost/ha
1±5 [sum]
6 and onwards
1±6
Wood yield and cost/ha
Wt (t)
Collect
De-coat
Shell
Total
Wt (t)
Fell etc.
Total cost (3)
(9.25)
(7.50)
(16.75)
21
17
38
21
17
38
17
14
31
59
48
107
(0.0)
(4.0)
(4.0)
0
20
20
59
68
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.
$343/ha of which $76 is for labour and $255 for
fertilizer with the remaining $12 for plough hire,
tools and seeds etc. From year 6, the annual
maintenance cost is $123/ha of which $102 is for
fertilizer and $21 for labour.
From year 6 and onwards, the labour cost of
harvesting 7.5 t of fruit and extracting the seed is
$48/ha and that for cutting and preparing 4 t of
wood for fuel and poles is $20/ha, giving a total
harvesting cost of $68/ha. It is anticipated that
the coat of the fruit can be sold at $16 per tonne,
the shell at $25/t and the seed at $117/t. This latter price is assuming the extracted plant oil is
used for soap making. This gives an average selling price, in terms of the whole fruit, of $65/t
(air dry). Similarly, the ex-farm price of fuelwood
is $25/t (air dry). The anticipated income per hectare is given in Table 5. From the sixth year
Table 5
J. curcas: estimated yield and income from the fruit and wood
(units: US$ per hectare ex farm)a
Year
Coat
Shell
Seed
Sub-total
Wood
Total
(price $/t)
1±5
6 onwards
1±6
(16)
44
36
80
(25)
56
45
101
(117)
498
404
902
598
485
1083
(25)
0
100
100
598
585
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 transport 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.
onwards, the gross income would be $585 and
the net income $394/ha/y. (If only the seed is
sold then the net income is reduced to $233/ha).
The net return to the farmer, assuming that s/he
provides the labour input would be $480/ha/y.
The return on invested capital is more than
100%. No rent has been included in the above
costs, but if a ®gure of $100/ha is assumed, then
the return is reduced to about 40%. This may
seem high, but in reality, it is just over $1 per
day from year 6 onwards for a one hectare farm,
if rent is included.4
These ®gures give an idea of the pro®tability
of jatropha grown as a commercial fruit crop in
a high rainfall area with a favourable market for
the products, especially the oil. In regions with
lower rainfall yields will be less. For example, if
the average annual rainfall is 500 mm per year,
the above ground net primary production may be
of the order of about 6 air-dry tonne per year.
But costs would fall more or less proportionately
with potential production, because the fertilizer
demand would also decrease. If little or no fertilizer is added, then fruit production would be rela4
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 ($244/ha excluding labour costs).
Thus as a commercial venture, it is marginally pro®table
unless income can be generated from the sale of other products such as honey, tannin (bark/leaves) and medicines
(leaves/fruit). This is why it is important to investigate all
markets and decide on a strategy, before promoting any crop,
plant oil or otherwise.
12
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
Table 6
The cost of jatropha oil production and the price of competing productsa
Country
India
Production process
Industrial
Operating days per yeare
Input: t of seed/y
Output: t seed cake/yi
Output: t plant oil/y
Output: litre plant oil/y
Cost of production per litre (US cents)
Seed processing
Seed delivery ex-processing
Oil manufacture
Total cost
Selling price of substitute products (US cents per litre)p
Kerosene (paran)
Diesel
Plant oil/tallow oil
Seed cake (per litre of oil)q
a
Zimbabwe
b
Hand pressc
Motor pressd
250
1000f
730
270
293,500
250
13.75g
10.65
3.10
3,375j
250
184.2h
141.93
42.32
46,000j
4.77k
62.25m
5.87
72.89
5.70l
46.04n
16.44o
68.18
5.61l
45.25n
14.59o
65.45
7.10
16.57
73.60
8.71
11.37
25.03
67.08
11.05
11.37
25.03
67.08
10.80
Source: [12,13,17±19] and author's estimates.
The Indian factory is 50 years old and no machinery cost ®gures are available. The following yearly cost ®gures were given (in
US$): 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-factory.
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 estimated 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.
b
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
tively low and there would be more woody biomass production. This may be desirable for hedging purposes, but expectations of good fruit
yields should be discounted. If the only market
for the oil is as a diesel substitute, then it uneconomic to grow the plant for this end-use
(Table 6). Both the farmer and the oil producer
would make a loss!
Table 6 gives the costs of production for three
di€erent methods of oil manufacture in two
countries. The Indian example has the lowest
cost components, with the Zimbabwe hand press
showing the highest costs. However, what all
these manufacturing processes indicate, is that
the present cost of producing oil from the jatropha plant, assuming that the grower, processor,
transporter etc. receive adequate returns for their
e€orts, is much more than the selling price of
diesel and kerosene.
Of course, the seed cake has a value and this
will improve the pro®tability of the oil milling
business. But the income from one product
should not be used to subsidize that of another
product. In other words, the plant oil should not
be sold for diesel (or kerosene) if there is a more
pro®table market for the oil, as there is in the
case of the examples given in Table 6. The excess
income earned from the sale of the plant oil plus
seed cake could be used to purchase diesel etc.,
rather than subsidizing the purchasers of oil sold
as a diesel substitute. This latter policy will leave
the grower and oil manufacturer worse o€ and
discourage pro®table rural industries such as
soap making.
8. Discussion
J. curcas is a versatile plant with several actual
and potential uses. The oil from the seed of the
plant is potentially the most valuable end product. However, for some projects ®nanced by
donors, NGOs and/or governments, too much
emphasis has been placed on using the oil as a
diesel or kerosene substitute. At present, this
appears to be a sub-optimal solution, for its price
as a diesel substitute is much less than for other
uses and the technology has not been fully
13
proved. Assuming a fair return to the growers,
fruit processors, transporters, traders and oil
manufacturers, the growing and production costs
for the oil are three to ten times the selling price
of diesel and kerosene in most developing
countries. Thus, it cannot compete with hydrocarbon fuels, unless donors, the state or the
growers/producers subsidize the plant oil. Of
course, the various cost components could be
exaggerated and the oil recovery percentage
underestimated, but this does not invalidate the
argument that other potential end-uses are more
pro®table.
In many countries, the oil could be used for
soap making and in most cases it should be a
pro®table venture. Soap making can be and is
undertaken in rural areas by small-scale entrepreneurs; this appears to be the market to aim for at
present. In addition, the oil cake can be used as
a fertilizer or fuel. Heat is required in the oil
extraction process and the shells and the fruit
coat could supply this, with the ash being sold as
a fertilizer. The entrepreneurs could then use
some of the pro®ts to buy diesel to run other
ventures!
A potential problem is the availability of suitable presses for jatropha oil. Sun¯ower seed
presses have been used, but these are not completely satisfactory and technical problems are experienced as well as below optimum recovery of
oil.
It is possible to detoxify seed cake, but currently, it does not appear to be cost e€ective.
There are varieties of non-toxic jatropha nuts
that may produce edible oil suitable for human
consumption and seed cake appropriate for animal feed. These varieties are available in Mexico
and being tested in some countries at present. If
they are successful, then a lucrative market could
open up for edible oil and cake with a price similar to sun¯ower oil. However, jatropha would
loose its advantage as a hedging plant.
In addition, several parts of the jatropha
plant have medical and cosmetic uses. The economics of making such products should be investigated and the markets for the products
researched. Again, such products may turn out
to be more pro®table than using jatropha for
14
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
fuel. All non-energy uses of the products from
J. curcas should be tabulated to provide a range
of options.
Jatropha is also an excellent hedging plant and
it should be cost competitive with a traditional
post and wire fence. If Jatropha is to be grown
as a commercial crop, especially for fruit production, the addition of fertilizer is a necessity.
The seed cake could be applied to the plantation
and/or nitrogen-®xing trees grown in combination with jatropha. Unless this is done, seed
production will diminish as the land becomes
exhausted. The various management techniques
should be recorded and gaps ®lled where knowledge is missing. This is essential if this plant is to
be accepted by farmers.
In order to re-stimulate the interest in jatropha, the emphasis should be adjusted and moved
away from its use as a diesel substitute or as a
household cooking and illumination fuel. The
focus should be switched to examining all the
attributes of the plant within various land use
systems and to develop and expand the most
pro®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
Digging pit
Applying FYM (Farmyard manure)
Seeding
Filling pit
Weeding
Applying fertilizer
Year 1. Initial Establishment
Year 2. Weeding
Applying fertilizer
Total year 2
Year 3. Applying fert.
Year 4. Applying fert.
Year 5. Applying fert.
Year 6 and onwards. Applying fertilizer
0.8
6.5
1.5
0.5
3.3
6.5
1.1
22.2
6.5
1.4
7.9
3.5
7.1
14.1
21.2
9.0
0.0
7.5
2.8
0.0
0.0
20.5
39.8
0.0
6.9
6.9
16.9
33.9
67.7
101.6
11.8
6.5
9.0
3.3
3.3
6.5
21.6
62.0
6.5
8.3
14.8
20.4
41.9
81.8
122.8
Animal drawn plough
1600 pits per ha
1 kg per hole
two seeds per hole
160 kg NPK, two dressings
170 kg seed cake
420 kg seed cake
840 kg seed cake
1680 kg seed cake
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).
K. Openshaw / Biomass and Bioenergy 19 (2000) 1±15
15
A.2. Harvesting cost jatropha fruit and wood (Units: $ per hectare)b
Yield/ha (tonnes)
Collect
Remove coat
Shell
Total
Fruit
Year 2 (0.50)
Year 3 (1.25)
Year 4 (2.50)
Year 5 (5.00)
Year 6 (7.50) and onwards
Wood
Year 6 (4.00) and onwards
Total Year 6. Fruit and wood
1.15
2.87
5.75
11.50
17.25
Fell/Prune
6.25
23.50
1.15
2.87
5.75
11.50
17.25
Cross cut
6.25
23.50
0.92
2.31
4.60
9.20
13.80
Cart/Stack
7.50
21.30
3.22
8.05
16.10
32.20
48.30
a
20.00
68.30
Labour cost $1 per day. Labour 95% of above costs, tools/sacks etc. 5%. Twelve adapted and author's estimates.
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