• Energy Research

Most households in sub-Saharan Africa rely on wood-based cooking fuels and their number is expected to rise. Despite this, national and subnational energy policies often neglect biomass cooking fuels. A Formative Scenario Analysis process is applied to show how the cooking fuel sector in Kilimanjaro Region (Tanzania) and Kitui County (Kenya) might evolve by 2030. In order to provide relevant knowledge for potential energy policies, this paper aims to identify the main drivers impacting the cooking fuel sector, and to assess and explore current and future demand and supply potential of biomass cooking fuels. Our results show that policies have the potential to substantially impact the future mix of cooking fuels and to foster or hamper the use of efficient cooking fuel technologies. Half of Kilimanjaro Region’s households could be supplied with biogas; in Kitui County, wood-based cooking fuels is likely to remain dominant but improving the efficiency of the technologies would reduce the demand for wood considerably. Hence, we argue that energy policies should explicitly consider biomass cooking fuels and endeavour to make this sector more sustainable and that priority should be given to increasing the sustainability of the biomass cooking fuel sector. Key leverage points to do so are improving the access to improved biomass technologies and capacity building.

Many observers view Jatropha as a miracle plant that grows in harsh environments, halts land degradation and provides seeds for fuel production. This makes it particularly attractive for use in Ethiopia, where poverty levels are high and the degradation of agricultural land is widespread. In this article, we investigate the potentials and limitations of a government-initiated Jatropha project for smallholders in northeastern Ethiopia from a green economy perspective. Data are based on a 2009 household survey and interviews with key informants, as well as on a 2012 follow-up round of interviews with key informants. We conclude that the project has not contributed to a greener economy so far, but has the potential to do so in the future. To maximize Jatropha’s potential, interventions must focus mainly on smallholders and pay more attention to the entire biofuel value chain.

En raison de sa disponibilité et de son abordabilité pour les populations les plus pauvres, l'énergie de la biomasse à base de bois reste vitale pour répondre aux demandes énergétiques locales – en particulier pour le combustible de cuisson – dans de nombreuses régions du monde en développement. Cependant, la pénurie croissante de matières premières (par exemple en raison de la déforestation) associée aux résultats socio-économiques et environnementaux négatifs des technologies de production et de consommation inefficaces, il est impératif d'identifier des solutions énergétiques alternatives qui profitent aux personnes sans nuire à l'environnement. En effet, la lutte contre la pauvreté énergétique est cruciale pour les efforts visant à atteindre les objectifs de développement durable au niveau des ménages. Cependant, les interventions visant à réduire la pauvreté énergétique doivent simultanément rechercher des solutions susceptibles de réduire l'empreinte carbone des personnes. Les empreintes carbone, ou les quantités d'émissions de gaz à effet de serre liées à des activités particulières, sont associées au changement climatique et à ses impacts. À l'échelle mondiale, les appels se sont intensifiés pour réduire l'empreinte carbone de la consommation d'énergie, y compris l'utilisation de combustibles issus de la biomasse. Au niveau local, les problèmes liés au changement climatique sont de plus en plus considérés comme des menaces particulières pour les communautés déjà vulnérables. Le présent article évalue l'empreinte carbone des solutions alternatives d'énergie de la biomasse pour la cuisson, en tant qu'aspect clé de leur performance environnementale. Il compare l'empreinte carbone du bois de chauffage, du charbon de bois, du biogaz, de l'huile de jatropha et des briquettes de résidus de culture. La recherche se concentre sur des technologies sélectionnées pour la production et la consommation d'énergie de la biomasse dans deux sites d'étude de cas dans des contextes ruraux et urbains du Kenya et de la Tanzanie. L'empreinte carbone est appliquée comme une approche méthodologique pour évaluer les options technologiques pour le développement durable dans les économies en développement connaissant une croissance démographique rapide, l'urbanisation et le développement industriel. Les résultats indiquent que la chaîne de valeur du charbon de bois non améliorée a une grande empreinte carbone. La chaîne de valeur de l'huile de jatropha semble détenir le plus grand potentiel de réduction de l'empreinte carbone, à condition que la matière première soit cultivée sous forme de couvertures autour des parcelles. Cependant, le potentiel de rendement limité des couvertures remet en question la viabilité économique de cette solution. Les résultats montrent en outre que l'empreinte carbone peut aider à sensibiliser et à informer les parties prenantes et les décideurs sur les chaînes de valeur de l'énergie de la biomasse alternatives et plus adaptées à l'environnement. Cependant, toute évaluation de la durabilité globale de ces chaînes de valeur devrait également intégrer les aspects socio-économiques et les facteurs influençant l'adoption. Debido a su disponibilidad y asequibilidad para las poblaciones más pobres, la energía de la biomasa a base de madera sigue siendo vital para satisfacer las demandas locales de energía, especialmente para el combustible para cocinar, en muchas regiones del mundo en desarrollo. Sin embargo, el aumento de la escasez de materias primas (por ejemplo, debido a la deforestación), junto con los resultados socioeconómicos y ambientales negativos de las tecnologías ineficientes de producción y consumo, hacen que sea imperativo identificar soluciones energéticas alternativas que beneficien a las personas sin dañar el medio ambiente. De hecho, abordar la pobreza energética es crucial para los esfuerzos destinados a cumplir los objetivos de desarrollo sostenible a nivel de los hogares. Sin embargo, las intervenciones destinadas a reducir la pobreza energética deben buscar simultáneamente soluciones que puedan reducir la huella de carbono de las personas. Las huellas de carbono, o las cantidades de emisiones de gases de efecto invernadero vinculadas a actividades particulares, están asociadas con el cambio climático y sus impactos. A nivel mundial, se han intensificado los llamamientos para reducir la huella de carbono del uso de energía, incluido el uso de combustibles de biomasa. A nivel local, los problemas del cambio climático se consideran cada vez más como amenazas particulares para las comunidades ya vulnerables. El presente documento evalúa las huellas de carbono de las soluciones alternativas de energía de biomasa para cocinar, como un aspecto clave de su desempeño ambiental. Compara las huellas de carbono de la leña, el carbón vegetal, el biogás, el aceite de jatrofa y las briquetas de residuos de cultivos. La investigación se centra en tecnologías seleccionadas para la producción y el consumo de energía de biomasa en dos sitios de estudio de casos en contextos rurales y urbanos de Kenia y Tanzania. La huella de carbono se aplica como un enfoque metodológico para evaluar las opciones tecnológicas para el desarrollo sostenible en las economías en desarrollo que experimentan un rápido crecimiento demográfico, urbanización y desarrollo industrial. Los resultados indican que la cadena de valor del carbón vegetal no mejorada tiene una gran huella de carbono. La cadena de valor del aceite de jatrofa parece tener el mayor potencial de reducción de la huella de carbono, siempre y cuando la materia prima se cultive en forma de setos alrededor de las parcelas. Sin embargo, el limitado potencial de rendimiento de las coberturas pone en duda la viabilidad económica de esta solución. Los resultados muestran además que la huella de carbono puede ayudar a crear conciencia e informar a las partes interesadas y a los responsables de la toma de decisiones sobre cadenas de valor de energía de biomasa alternativas y ambientalmente más adecuadas. Sin embargo, cualquier evaluación de la sostenibilidad general de estas cadenas de valor también debe integrar los aspectos socioeconómicos y los factores que influyen en la adopción. Due to its availability and affordability for poorer populations, wood-based biomass energy remains vital in meeting local energy demands – especially for cooking fuel – in many regions of the developing world. However, increasing feedstock scarcity (e.g. due to deforestation) coupled with the negative socio-economic and environmental outcomes of inefficient production and consumption technologies make it imperative to identify alternative energy solutions that benefit people without harming the environment. Indeed, tackling energy poverty is crucial to efforts aimed at meeting sustainable development goals at the household level. However, interventions aimed at reducing energy poverty must simultaneously seek solutions that might reduce people's carbon footprint. Carbon footprints, or the amounts of greenhouse gas emissions linked to particular activities, are associated with climate change and its impacts. Globally, calls have intensified to reduce the carbon footprint of energy use, including use of biomass fuels. Locally, climate change issues are increasingly seen as posing particular threats to already vulnerable communities. The present paper evaluates the carbon footprints of alternative biomass energy solutions for cooking, as one key aspect of their environmental performance. It compares the carbon footprints of firewood, charcoal, biogas, jatropha oil, and crop residue briquettes. The research focuses on selected technologies for biomass energy production and consumption in two case study sites in rural and urban contexts of Kenya and Tanzania. Carbon footprinting is applied as a methodological approach to evaluating technological options for sustainable development in developing economies undergoing rapid population growth, urbanization, and industrial development. Results indicate that the unimproved charcoal value chain has a big carbon footprint. The value chain for jatropha oil appears to hold the greatest potential for carbon footprint reductions, as long as the feedstock is grown in the form of hedges around plots. However, the limited yield potential of hedges calls into question the economic viability of this solution. Results further show that carbon footprinting can help to raise awareness and inform stakeholders and decision-makers about alternative, environmentally more suitable biomass energy value chains. However, any assessment of the overall sustainability of these value chains should also integrate socio-economic aspects and factors influencing adoption. نظرًا لتوافرها والقدرة على تحمل تكاليفها للسكان الأكثر فقرًا، تظل طاقة الكتلة الحيوية القائمة على الأخشاب حيوية في تلبية متطلبات الطاقة المحلية – خاصة لوقود الطهي – في العديد من مناطق العالم النامي. ومع ذلك، فإن زيادة ندرة المواد الوسيطة (على سبيل المثال بسبب إزالة الغابات) إلى جانب النتائج الاجتماعية والاقتصادية والبيئية السلبية لتقنيات الإنتاج والاستهلاك غير الفعالة تجعل من الضروري تحديد حلول الطاقة البديلة التي تفيد الناس دون الإضرار بالبيئة. والواقع أن معالجة فقر الطاقة أمر بالغ الأهمية للجهود الرامية إلى تحقيق أهداف التنمية المستدامة على مستوى الأسر المعيشية. ومع ذلك، يجب أن تسعى التدخلات الرامية إلى الحد من فقر الطاقة في وقت واحد إلى إيجاد حلول قد تقلل من البصمة الكربونية للناس. ترتبط آثار الكربون، أو كميات انبعاثات غازات الدفيئة المرتبطة بأنشطة معينة، بتغير المناخ وآثاره. على الصعيد العالمي، تكثفت الدعوات للحد من البصمة الكربونية لاستخدام الطاقة، بما في ذلك استخدام وقود الكتلة الحيوية. وعلى الصعيد المحلي، يُنظر إلى قضايا تغير المناخ بشكل متزايد على أنها تشكل تهديدات خاصة للمجتمعات الضعيفة بالفعل. تقيّم هذه الورقة البصمات الكربونية لحلول طاقة الكتلة الحيوية البديلة للطهي، باعتبارها أحد الجوانب الرئيسية لأدائها البيئي. ويقارن البصمات الكربونية للحطب والفحم والغاز الحيوي وزيت الجاتروفا وقوالب بقايا المحاصيل. يركز البحث على تقنيات مختارة لإنتاج طاقة الكتلة الحيوية واستهلاكها في موقعين لدراسة الحالة في السياقات الريفية والحضرية في كينيا وتنزانيا. يتم تطبيق البصمة الكربونية كنهج منهجي لتقييم الخيارات التكنولوجية للتنمية المستدامة في الاقتصادات النامية التي تشهد نموًا سكانيًا سريعًا والتحضر والتنمية الصناعية. تشير النتائج إلى أن سلسلة قيمة الفحم غير المحسنة لها بصمة كربونية كبيرة. يبدو أن سلسلة القيمة لزيت الجاتروفا تحمل أكبر إمكانات لتخفيض البصمة الكربونية، طالما أن المادة الوسيطة تنمو في شكل تحوطات حول قطع الأراضي. ومع ذلك، فإن إمكانات العائد المحدودة للتحوطات تشكك في الجدوى الاقتصادية لهذا الحل. تظهر النتائج كذلك أن البصمة الكربونية يمكن أن تساعد في زيادة الوعي وإبلاغ أصحاب المصلحة وصناع القرار بسلاسل قيمة طاقة الكتلة الحيوية البديلة والأكثر ملاءمة للبيئة. ومع ذلك، فإن أي تقييم للاستدامة الشاملة لسلاسل القيمة هذه يجب أن يدمج أيضًا الجوانب الاجتماعية والاقتصادية والعوامل التي تؤثر على التبني.

In many parts of the eastern African region wood-based fuels will remain dominant sources of energy in coming decades. Pressure on forests, especially in semi-arid areas will therefore continue increasing. In this context, the role of liquid biofuels as substitutes for firewood and charcoal, to help reducing pressure on woody biomass and contributing to a better energy security of rural communities, has remained controversial among researchers and practitioners. At household level, the economic and technical feasibility of straight vegetable oil (SVO) was assessed mainly on Jatropha curcas, with unpersuasive results. So far nothing is known about the suitability as an energy carrier of Jatropha mahafalensis Jum. & H. Perrier, the only endemic representative of the Jatropha genus in Madagascar. This paper explores the potential of this plant as a biofuel feedstock in the agro-pastoral area of Soalara, in the semi-arid south-western part of Madagascar. Only hedge-based production was considered to rule out competition over land with food crops. Yield data, the length of currently existing hedges and energy consumption patterns of households were used to assess the quantitative potential and economic viability of J. mahafalensis SVO for lighting and cooking. Tests were conducted with cooking and lighting devices to assess their technical suitability at household level. The paper concludes that J. mahafalensis hedges have some potential to replace paraffin for lighting (though without much economic benefit for the concerned households), but not to replace charcoal or firewood for cooking. The paper recommends that rural energy strategies in similar contexts do not focus only on substituting current fuels with SVO, but should also take into consideration other alternatives. In the case of cooking, there seems to be substantially more potential in increasing the efficiency of current fuel production and consumption technologies (kilns and stoves); and in the case of lighting, solutions based on SVO need to be compared against other options such as portable solar devices.

Abstract In East Africa, charcoal and firewood will remain the main sources of energy for cooking for the next two to three decades. Corresponding energy policies are needed that set proper priorities and improve the sustainability of the biomass energy sector. In this paper, we assess the supply potentials of wood-based and non-woody biomass fuels in the Kilimanjaro Region of Tanzania, and formulate recommendations to support sustainable biomass energy strategies in East Africa. We differentiate between tree types of potentials: the supply potential, the access potential, and the production potential. In order to calculate these potentials, we use a spatial Bayesian network that specifically enables accounting for uncertainties in the data and model. The main results show: (1) that agroforestry and small-scale mixed farming are the land use types with the highest potentials, (2) that firewood, charcoal, and biogas have substantial potential, whereas crop residue briquettes and Jatropha oil have only minor potentials, and (3) that such estimates can be subject to substantial uncertainties. Based on these results, we recommend that biomass energy strategies in East Africa consider the specific assets and limiting factors of the various fuel types and land use types in order to improve the supply of sustainable biomass cooking fuels.

Between 2004 and 2007, NGOs, community based organisations and private investors promoted jatropha in Kenya with the aim of generating additional income and producing biofuel for rural development. By 2008 it became gradually evident that jatropha plantations (both mono- and intercropping) are uneconomical and risky due to competition for land and labour with food crops. Cultivation of jatropha hedges was found to have better chances of economic success and to present only little risks for the adopting farmers. Still, after 2008 a number of farmers went on adopting jatropha in plots rather than as hedges. It is hypothesised that lack of awareness about the low economic prospects of jatropha plantations was the main reason for continued adoption, and that smallholder farmers with higher resource endowments mainly ventured into its cultivation. In this study we provide an empirical basis for understanding the role of households' capital assets in taking up new livelihood strategies by smallholder farmers in three rural districts in Kenya. For that purpose, we assess the motivation and enabling factors that led to the adoption of jatropha as a new livelihood strategy, as well as the context in which promotion and adoption took place. A household survey was conducted in 2010, using a structured questionnaire, to collect information on household characteristics and capital asset endowment. Data were analysed using descriptive statistics and non-parametric statistical tests. We established that access to additional income and own energy supply were the main motivation for adoption of jatropha, and that financial capital assets do not necessarily have a positive influence on adoption as hypothesised. Further, we found that the main challenges that adopting farmers faced were lack of access to information on good management practices and lack of a reliable market. We conclude that continued adoption of on-farm jatropha after 2008 is a result of lacking awareness about the low economic value of this production type. We recommend abandoning on-farm production of jatropha until improved seed material and locally adapted agronomic knowledge about jatropha cultivation becomes available and its production becomes economically competitive.

Access to affordable and renewable sources of energy is crucial to reducing poverty and enhancing rural development in countries of the global South. Straight vegetable oil was recently identified as a possible alternative to conventional biomass for rural energy supply. In this context, the Jatropha curcas Linn. species has been extensively investigated with regard to its potential as a biofuel feedstock. In contrast, only little is known about Jatropha mahafalensis Jum. & H. Perrier, which is an indigenous and endemic representative of the Jatropha genus in Madagascar. This paper explores the potential and suitability of J. mahafalensis as a biofuel feedstock. Seed samples were collected in the area of Soalara in south-western Madagascar in February and September 2011. Two agro-ecological zones (coastal area and calcareous plateau) and two plant age groups (below and above 10 years) were considered. These four sample groups were analyzed with regard to oil properties, element contents, and fatty acid profiles. Measured values differed greatly between the two harvests, probably owing to different climatic or storage conditions. No direct relation between age of trees or location and oil quality could be established. The analyses indicate that J. mahafalensis oil can be used in oil lamps, cooking stoves and stationary combustion engines for electrification or for biodiesel production. However, modifications in storage and extraction methods, as well as further processing steps are necessary to enable its utilization as a straight vegetable oil and feedstock for biodiesel production. If these technical requirements can be met, and if it turns out that J. mahafalensis oil is economically competitive in comparison with firewood, charcoal, paraffin and petroleum, it can be considered as a promising feedstock for rural energy supply.

In sub-Saharan Africa, the high demand for wood-based cooking fuels calls for urgent policy action to steer the cooking energy sector towards more sustainability. While the subnational scale is growing in importance for policy planning, current energy assessments still only consider individual entities without taking into account resource flows. Ignoring flows of biomass cooking fuels in supply–demand assessments is a system boundary problem that can lead to misleading policy recommendations. In this paper, we tackle the boundary problem in subnational supply–demand assessments and provide a tool to support knowledge-based decision-making on the management of biomass cooking fuels in sub-Saharan Africa. Using Kitui County as a case study, we developed and tested an approach consisting of a supply model, local demand model, balance model, availability model, and adjusted balance model. The balance model only considers local fuel supplies and demand, whereas the adjusted balance model also considers external demand, which reduces the locally available supply of fuel. The results show that fuel demand and supply are spatially heterogeneous and vary between wood-based and non-woody fuels, and that the transport distance of fuels strongly affects local fuel availability and determines whether the supply–demand balance is positive or negative. We conclude that subnational energy policies should consider geographical distribution of supply and demand, aim to increase the fuel mix, consider external demand in supply–demand assessments, and differentiate between fuels for self-consumption and the market.