Innovative jatropha biofuel production in Malawi

5th July 2013

By: Jeremy Wakeford

  

Font size: - +

Enthusiasm surrounding conventional biofuels such as maize-based ethanol has waxed and waned over the past few years, particularly in the African context, where food security is a major issue. On a recent trip to Malawi, I had the opportunity to visit a small company called Bio Energy Resources Limited (Berl), which is pioneering a novel model of biofuel production based on the jatropha plant.

Jatropha curcas is a succulent plant originating in Central America that grows to several metres in height and is reputed to be well adapted to semi-arid conditions. Trees take around five to six years to reach maturity, after which they produce oil-rich seeds for up to 25 years.

Smallholder farmers plant jatropha trees as a boundary crop around field crops like maize and sorghum. They use chicken manure and/or a small amount of compost when they plant out the seedlings and add some compost on a yearly basis, but trees are typically not irrigated. The average yield is 1 kg of nuts per tree each year, and each nut contains seeds with an oil content of around 25%.

Berl guarantees a market for jatropha seeds to the smallholder farmers. The company’s processing facility – located on the outskirts of Malawi’s capital city, Lilongwe – currently contains one oil press that can process about 4 000 t of jatropha nuts a year. But the design is modular and can easily be scaled to three and eventually nine presses. The main product is jatropha straight vegetable oil (JSVO), which is blended with both diesel and paraffin for fuelling diesel engines and paraffin lamps respectively.

Berl’s factory also produces a biofertiliser with the leftover organic matter from the nuts, which is sold mainly to commercial farmers. The biofertiliser contains 4% to 6% nitrogen, 1% to 2% phosphorus and 1% to 2% potassium. Berl’s process is therefore zero waste, in the sense that it uses 100% of the jatropha nuts.

This model has several advantages in the Malawian context. Crucially, as jatropha fruits are not edible and are planted on the boundary of food crops, they do not compete with food production. In fact, the jatropha trees serve as a natural fence, helping to reduce crop losses to livestock.

The cultivation and harvesting processes are labour intensive, which is appropriate in a country where 85% of the population are engaged in subsistence agriculture. Further, the sale of the nuts provides a supplementary source of income during the so-called ‘hungry season’ – before food crops are harvested. Berl says that farmers with between 400 and 600 jatropha trees can earn $100 to $130 a year, which is not a trivial amount, given that four-fifths of the population survive on less than $730 a year.

On the downside, jatropha is a long-term investment and will take several years before financial viability can be established. Yields from the plants can also vary considerably, depending on soil and rainfall conditions.

A key uncertainty surrounds the energy return on investment (EROI) – the ratio of biofuel energy output to energy inputs. The main energy inputs are in the form of fertilisers, diesel (to run the trucks that bring the nuts to the factory) and grid electricity or diesel-powered generators to run the processing plant and general operations. International esti- mates of EROI for biodiesel have ranged between a high of 8 to 1 and lows of around 1.3 to 1. On the lower end, this ratio implies very marginal net energy gains and tenuous economics.

Berl has the support of the Malawi government and has established good working relations with five Ministries. The Malawi government is keen to reduce the country’s reliance on imported petroleum fuels and thus looks favourably on biofuels. Berl works with the Malawi Energy Regulatory Authority on production licensing and pricing and with the National Bureau of Standards on product quality. The company is also coope- rating with the Agricultural Research and Extension Trust on fertiliser trials.
Fuel prices in Malawi are set by government, which recently adopted a similar model to that used by the Department of Energy in South Africa, that is, benchmarking on the international price of refined fuels. JSVO is currently marketed to fuel blenders with a discount to the wholesale price of diesel in order to incentivise market uptake.

Berl’s current scale of operation is very small, but it is targeting a yearly JSVO output of 20-million litres, along with 55 000 t of bio- fertiliser, using the nuts harvested by 100 000 smallholder farmers from some 60-million jatropha trees. The company is targeting the domestic market only and has no plans to export to Europe or other regions.
The way that Berl is conducting its jatropha operation is well suited to the local context of subsistence farming and looks good from an ecological and social sustainability point of view. Time will tell whether the economic dimension also proves sustainable.

Edited by Martin Zhuwakinyu
Creamer Media Senior Deputy Editor

Comments

The content you are trying to access is only available to subscribers.

If you are already a subscriber, you can Login Here.

If you are not a subscriber, you can subscribe now, by selecting one of the below options.

For more information or assistance, please contact us at subscriptions@creamermedia.co.za.

Option 1 (equivalent of R125 a month):

Receive a weekly copy of Creamer Media's Engineering News & Mining Weekly magazine
(print copy for those in South Africa and e-magazine for those outside of South Africa)
Receive daily email newsletters
Access to full search results
Access archive of magazine back copies
Access to Projects in Progress
Access to ONE Research Report of your choice in PDF format

Option 2 (equivalent of R375 a month):

All benefits from Option 1
PLUS
Access to Creamer Media's Research Channel Africa for ALL Research Reports, in PDF format, on various industrial and mining sectors including Electricity; Water; Energy Transition; Hydrogen; Roads, Rail and Ports; Coal; Gold; Platinum; Battery Metals; etc.

Already a subscriber?

Forgotten your password?

MAGAZINE & ONLINE

SUBSCRIBE

RESEARCH CHANNEL AFRICA

SUBSCRIBE

CORPORATE PACKAGES

CLICK FOR A QUOTATION