| Application of biomass-energy technologies |
|I. Woodfuel production technologies|
Woodfuel accounts for about 10 per cent of the total energy used in the world. It provides about 20 per cent of all energy used in Asia and Latin America, and about 50 per cent of total energy used in Africa (Arnold, 1991, Murray and De Montalembert, 1992). However, it is the major source of energy , in particular for domestic purposes, in poor developing countries: in 22 countries, woodfuel accounted for 2549 per cent, in 17 countries, 50-74 per cent, and in 26 countries, 75-100 per cent of their respective national energy consumption (UNCHS, 1984).
More than half of the total wood harvested in the world is used as woodfuel (Eckholm, 1976). For specific countries, for example, the United Republic of Tanzania, the contribution can be as high as 97 per cent (Mnzava 1990).
Although woodfuel is the major source of energy for most rural and low-income people in the developing world, the potential supply of woodfuel is dwindling rapidly, leading to scarcity of energy and environmental degradation (UNCHS, 1990). It is estimated that, for more than a third of the world population, the real energy crisis is the daily scramble to obtain woodfuel to meet domestic use (Eckholm, 1975).
Current studies on woodfuel supply in developing countries have concluded that woodfuel scarcities are real and will continue to exist, unless appropriate approaches to resource management are undertaken (Arnold, 1991, SADCC Energy Sector 1992b). The increase of woodfuel production through efficient techniques, can, therefore, be considered as one of the major pre-requisites for attaining sustainable development in developing countries.
The following paragraphs describe the main points of case studies on woodfuel technologies which were conducted in eight Southern African countries, namely, Botswana, Lesotho, Malawi, Mozambique, Swaziland, the United Republic of Tanzania, Zambia and Zimbabwe.