Biomass currently supplies about a third of the developing countries’ energy varying from about 90% in countries like Uganda, Rawanda and Tanzania, to 45 percent in India, 30 percent in China and Brazil and 10-15 percent in Mexico and South Africa. The crucial questions are whether the two billion or more people who are now dependent on biomass for energy will increase. The fact that 90 percent of the worlds population will reside in developing countries by about 2050 probably implies that biomass energy will be with us forever. Planting of more trees in forest reserves for reducing global warming has been universally accepted, the idea being that carbondi-oxide absorption would continue until the trees mature say for 40 to 100 years. Although it is recognized that this is not a permanent solution this “carbon sequestration” strategy buy time to develop alternative energy sources.
1.1 Tropical deforestation is currently a significant environment and development issue. At the global level, according to recent estimates by FAO the annual tropical deforestation rate for the decade 1981 to 1990 was about 15.4 million h (Mha) . According to the latest data published in 1994, for the assessment period 1989-1991, the total area under forests is 64.01 Mha accounting for 19.5 percent of India’s geographic area .
1.2 At present there is hardly 0.4 percent forest below 25cm rainfall zone and 1.3 percent above 30 cm rainfall zone. There is rapid depletion of forest products and in order to provide alternative energy sources a change is needed in conventional forestry management.
1.3 Four broad categories of biomass use can be distinguished – a) basic, e.g. food, fiber, etc.; b) energy, e.g. domestic and industrial; c) materials, e.g. construction and d) environmental and cultural, e.g. the use of the fire. Biomass use through the course of history has varied considerably, greatly influenced by two main factors population size and resource availability.
1.4 Since the annual photosynthetic production of biomass is about eight times the world’s total energy use and this energy can be produced and used in an environmentally sustainable manner, while emitting net CO2, there can be little doubt that this potential source of stored energy must be carefully considered in any discussion of present and future energy supplies. The fact that nearly 90 percent of the worlds population will reside in developing countries by a bout 2050 probably implies that biomass energy will be with us forever unless there are drastic changes in the world energy trading pattern.