Spatial and temporal variation in domestic biofuel consumption rates in southern Africa

• Main Author: Tshikalanke, Rabelani Phillip
• Format: Others
• Language: en
• Published: 2008
• Subjects: spatial; temporal; variation; domestic biofuel; consumption; Southern Africa
• Online Access: http://hdl.handle.net/10539/5865

Biomass burning is an important source of trace gases such as CO2, CO and NO, which influence regional and global atmospheric chemistry. Biomass is burnt in bush fires as well as in households as an energy source. Even though there have been numerous studies on domestic biofuel use in Africa over the last two decades there is still a lack of consumption data on the continent. Biofuel is used in rural and urban areas in Africa, but this project focuses on rural consumption. This project aims to quantify biofuel use at representative rural sites around southern Africa and to investigate the spatial and temporal variation. Three sites, one in the south, central and northern parts were selected in each of seven countries (Botswana, Namibia, South Africa, Mozambique, Zambia, Zimbabwe and Malawi). Consumption rates for all fuel types were determined by weighing the fuel used throughout the day. The survey was conducted during the months of May 2003 to February 2004. The forms of biofuel used over southern Africa were found to be wood, charcoal and to a lesser extent maize residue. To obtain a consumption estimate for the whole of rural southern Africa consumption values for Swaziland and Lesotho from previously studies were included. The total annual rural fuelwood consumption in southern Africa is estimated to be 54.7 ± 3.5 Tg with an average daily consumption of 2.55 kg person-1 day-1 . South Africa has the highest consumption of wood and Swaziland the least. While fuelwood was used in all countries charcoal was only consumed in the rural areas of South Africa, Zambia and Mozambique. Rural southern Africa is estimated to consume 8.1 ± 0.8 Tg of charcoal per year. Malawi was the only country to consume maize residue at an average rate of 0.51 ± 0.16 kg person-1 day-1, leading to a consumption of 1.8 ± 0.1 Tg yr-1 over the whole region. The total rural biofuel consumption over southern Africa was estimated to be 64.6 ± 3.6 Tg yr-1. Namibia and South Africa had increased consumption rates between August and October, and Zambia shows slightly higher consumptions between May and July. The other countries show little monthly variation with no specific seasonal trends. There was a slight positive relationship (r2 = 0.168; p = 0.065) between consumption rate and altitude, but the data is very scattered due to monthly variation. Slopes are only shown to be significant between January and March. Altitude is therefore not shown to be a significant controlling factor of biofuel consumption in this study.