A magic tree? Jatropa scrutinized as alternative energy source in Burkina Faso.

With prices for limited sources of fossil energy rising, energy from biomass sources has become an interesting alternative. As the price of (imported) fossil fuels is prohibitively high for people living in rural areas in many West African countries, there is widespread use of traditional biomass sources such as fuel wood and charcoal for cooking and preparing beverages like beer brewed from sorghum. However, high population growth and increasing need for energy are leading to the overuse of wood resources, which is resulting in deforestation of vast land areas and severe soil degradation.

Jatropha: pros and cons
In this context, the Jatropha tree has shifted into the focus of worldwide attention in recent years. This low-water demanding tree is promoted as the most promising energy crop for dry regions. It is claimed that it can be grown on nutrient-poor soils and still produce considerable amounts of oily seeds, which can be used as a source of energy. Moreover, Jatropha can even contribute to restoring these soils. Unfortunately, many of these assertions are not grounded scientifically and cultivating Jatropha proves to be more complicated in practice than thought.

Theory and practice
This has been shown by a doctoral study conducted at ZEF assessing Jatropha cultivation systems in Burkina Faso. The results indicate very low seed yields from the Jatropha trees in general, even though most farmers grow Jatropha on their more fertile soils, anticipating higher incomes. It also appears that cultivating Jatrophra is very labor-intensive. An area larger than four soccer fields (four hectares) would have to be planted with Jatropha in order to produce the amount of energy that a six-person household requires for cooking. The researchers realized that cultivating Jatropha means competing with food crops for scarce resources such as labor and land. In the end, the farmers are even losing income with Jatropha: Current low market prices mean that the income generated by selling Jatropha seeds does not compensate for the losses in food production.

Expectations not met
The experiment to cultivate Jatropha on marginal soils - abandoned from agricultural production - failed completely. Only traditionally grown Jatropha trees, often used as living fences around agricultural fields, proved to be compatible with existing agricultural systems. Living fences require little space and, moreover, provide some protection from soil erosion and crops from browsing animals. Additionally, the oil from the seeds can be used for decentralized energy supply.

Recommendations
To become a competitive source of energy, Jatropha cultivation systems have to be intensified in a sustainable way. This includes developing improved planting material, optimizing management regimes and offering adequate training to farmers. Overall, the case of Jatropha production in Burkina Faso shows that the cultivation of energy crops can contribute to a better energy supply in rural areas while additionally providing ecosystem services. Trans-disciplinary approaches - developed together with the local population and thus best-adapted to local conditions and needs - are the most promising method for the successful implementation of innovative actions.

Authors: <link mail window for sending>Sophia Baumert and <link mail window for sending>Jan Henning Sommer

The research was funded by the Dreyer Foundation.

You can also read this article in <link fileadmin webfiles downloads zefnews zef_news_28_en.pdf download file>ZEF news no. 28 (page 9).