Saturday, November 19, 2005

Jatropha in Africa


Much has been made of the notion that biofuel consumes more energy during production, through energy expenditures for fertilizer, irrigation, and refining, than it can yield when burned. That is to say, biofuel has been accused of having a negative energy payback. In some cases, under very specific assumptions, this is true, but there is great variation in the energy paybacks for various biofuels. Some studies indicate biofuel can deliver an energy payback as high as 10:1 or even 20:1.

Jatropha isn't a well known biofuel, like corn or sugar cane, but when it comes to producing bio-diesel, Jatropha may be have the highest energy payback of any biofuel. Moreover, unlike corn or sugar cane, Jatropha is a perennial, yielding oil seed for decades after planting, and it can grow without irrigation in arid conditions where corn and sugar cane could never thrive.

The African continent, which at 29 million square kilometers in size is nearly as large as Asia, is relatively sparsely populated by comparison. It is also a continent of spectacular natural wealth, having vast reserves of land with climates ideal for growing Jatropha. Over half of the land in Africa is considered suitable for Jatropha cultivation. If only 2% of that land was used to cultivate Jatropha, it would yield as much oil per year as U.S. oil companies expect - best case - to remove from Alaska's north slope over the next 20 years. And after 20 years, these fields of Jatropha would still be producing oil, whereas the Alaskan oil fields would be dry.

If, to use an extreme case, 25% of Africa's land deemed suitable to grow Jatropha were used for that purpose, the yearly output would match 100% of the current oil consumption in the USA. Needless to say, such a scenario would also erase forever the landscape of poverty that has plagued Africans for decades. And where the Sahara and Kalahari are on the march, Jatropha can grow, storing moisture, stablizing soil, and slowing if not reversing desertification.

It isn't practical to expect Jatropha, or biofuel in general, to completely replace crude oil. But conventional estimates of how much biofuel might actually be produced if grown on a massive commercial scale worldwide may be low, particularly when taking into account what may be superior yields from crops such as Jatropha. - Ed "Redwood" Ring

Jatropha curcus is unusual among tree crops

Perhaps its most unusual feature is its modular construction. The dry fruits and seeds will remain on the tree for some time, before falling to the ground, especially under dry conditions. Benefits include but are not limited to:

Oil as raw material: Oil has a very high Saponification value and is being extensively used for making soap in some countries. Also, the oil is used as an illuminant as it burns without emitting smoke.

Medicinal plant: The latex of Jatropha curcas (VanaErand or RatanJyot) contains an alkaloid known as "jatrophine" which is believed to have anti-cancerous properties.

Raw material for dye: The bark of Jatropha curcas (VanaErand or RatanJyot) yields a dark blue dye which is used for colouring cloth, fishing nets and lines.

Soil enrichment: Jatropha curcas (VanaErand or RatanJyot) oil cake is rich in nitrogen, phosphorous and potassium and can be used as organic manure.

Feed: Jatropha leaves are used as food for the tusser silkworm.

In addition to these benefits, scientists at Perdue University in the U.S. and elsewhere are working in the extraction of usable pharmaceutical derivatives from Jatropha Curcas while others are attempting to grow non-toxic plants (Mexico).

Preliminary research indicates Jatropha may display certain Anti-Tumor properties, Anti Malarial properties and research is advancing related to HIV/AID’s and immune system response enhancement. There are other levels of use that can be exploited. Direct fermentation of seed cake and pulp delivers an organic fertilizer that has a high potential for export to developed countries.

It is in the field of Bio Diesel fuel, however, that Jatropha's properties are the most exciting. At same power output, Jatropha curcas oil specific consumption and efficiencies are higher than those of diesel fuel. Tests conducted show that out of these various vegetable oils including copra, palm, groundnut, cottonseed, rapeseed, soya and sunflower - the lowest exhaust gas emissions were obtained with copra and Jatropha Curcas crude oil.


In a survey conducted by Dr. Guy Midgley, Chief Specialist Scientist of the Kirstenbosch Research Center of of the South African National Biodiversity Institute (Cape Town) over 1,080 million hectares land Africa could be termed prime growing regions for Jatropha Curcas on the African continent. A further 580 million hectares could be used making a total of 1,660 million hectares suitable for the growing of Jatropha Curcas.

On the map of Africa the dark areas represent prime Jatropha growing regions in Africa. These areas, comprising over 1,080 million hectares, or 10.8 million square kilometers, are ideal because the average annual rainfall exceeds 800 mm, and the minimum temperature of the coldest month is greater than 2 degrees centigrade.

The light green areas of the map are areas with average annual rainfall in excess of 300 mm, with the minimum temperature of the coldest month greater than 2 degrees centigrade. These areas, comprising over 580 million hectares, or 5.8 million square kilometers, are also viable regions for growing Jatropha.


The yield per hectare per year is up to 8.0 tons of Jatropha seed, which contain over 30% oil. At $320 (US$) per ton, this will translate into sales of Jatropha crude oil of $768 per hectare per year. Of potentially equal or greater value is the yield from Jatropha seeds of glycerin. Up to 7% of Jatropha seeds are made up of glycerin, which sells for up to $2,000 per ton. This translates into glycerin sales of up to $1,120 per year per hectare, or total sales of up to $1,888 per year per hectare.

Imagine, if only 3% of the land in Africa that is considered viable land to grow Jatropha was actually planted with Jatropha, with a yield of 8 tons per hectare per year and an oil content of 30% some 119 Million tons of Jatropha crude oil would be produced per year. The glycerin content at 7% of the 119 M tons would produce an additional 8.366 M tons. Glycerin is indeed a valuable by product.

In terms of annual revenues, if only 3% of the potential Jatropha growing regions in Africa were planted with Jatropha, based on a Jatropha crude oil price of $320 per ton and with glycerin selling at $2000 per ton a total sales value of $55 billion per year would be generated. Processing the crude oil into Bio Diesel would on average in Africa add a further 15% to the sales value. This sales value excludes other byproducts of Jatropha. Most African countries are oil dependent and foreign exchange expenditure would be reduced.

Jatropha farming could be an incredible contribution to economic development in Africa. Feasibility however is problematic due to the difficulty sourcing suitable financing. The two main reasons for failures to source funding are:

1) Land in many countries in Africa is not owned but leased. This effectively eliminates land being used as collateral by funders.

2) Start up agriculture projects are generally among the most difficult projects for which to obtain funding.

Moreover, financial models show that an assured supply of feed stock is required from a central area to ensure a viable project. Only when this is assured can out growers be considered to supplement the main supply chain. Projects where only marginal land is to be used will be very border line and unlikely to financially succeed. Good yields on marginal land are highly unlikely to be obtained.


There are still some inherent problems with Jatropha and research work is still required. We are learning more and more about the properties of Jatropha. These potential problems include:

1) Jatropha oil is hydroscopic – absorbs water and needs nitrogen blanketing on steel tanks. One issue that is quite clear is because Jatropha is high in acid, it has the tendency to degrade quickly, particularly if not handled properly through the supply chain.

2) Right from the time of expelling, the oil needs to be kept in storage conditions that prevent undue degradation. Exposure to air and moisture must be minimized - hence the need for nitrogen blanketing on the tanks.

3) The range of fatty acids present in the various seeds will differ but the oil and biodiesel that is produced must be acceptable. However, this assumes that that oil is fully degummed. The degumming may well be more of a problem than making biodiesel!

4) The phospholipid, protein and phorbol ester contents in edible Jatropha seem to be quite different compared to these contents in non-edible Jatropha. It needs to determined if this affects the degumming method. The degumming removes lecithin and other related compounds, so if these are high than a modified degumming method may be needed. If the oil is properly dried after degumming and kept under nitrogen blanketing this may suffice. Biodiesel companies are investigating storage requirements and the oxidative stability of Jatropha.

5) Seeds degrade as soon as they are picked and so careful storage and handling is required. In the warm humid atmosphere in countries such as Ghana the degradation of seeds can be rapid. Even in the U.K. seed storage is a problem. Recently a U.K. importer had samples of rapeseed that had been harvested and stored in wet weather. The analysis showed that they had 28% of free fatty acid! The free fatty acid must not increase above 2%.

6) There has never been a highly commercial group handling Jatropha Curcas harvest and derivatives.

Rubber Nitrile tanks are perfect for container shipping as there is no exposure to the atmosphere or the air, this is because they are collapsible and always work in a vacuum. They can be fitted in a 20ft – 30 ton container. Each container would hold about 22.4 tons Jatropha Curcas crude oil. Their use would prevent the problem of water absorption.

World Wide manufactures of Bio Diesel processors are beginning to recognize the need for their units to be able to accept more than one variety of vegetable oil. The pre-processors, (de-gumming units) must be designed to be “multi disciplinary”. Commercial Bio Diesel processors are expensive and it is financially essential for feed stock to be available on a continuous basis. Harvesting is seasonal and storage time has to be minimal due to the free fatty acids having to be no more than 2%.

Feasibility studies ideally need to be done but this is far too time consuming. The bio-diesel entrepreneur would need to take some statistical chances. By growing at the same time alternative crops to Jatropha curcus the problems may be somewhat reduced.

It makes sense that a bio-diesel entrepreneur should focus on the promotion of partnerships and in-house activities that support multiple crop development and improvement activities as well as seeking the add on values that are available.

Climate change will grossly increase African's poverty levels. A Bio Diesel 1 Group initiative introduced Stancom Tobacco to the benefits of growing Jatropha curcas for conversion into Bio Diesel. The photos in this article show the Stancom Tobacco's nurseries in Zambia. The harvested seed will be collected by BD1 Malawi and processed into crude oil.



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