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< prev - next > Energy Biogas KnO 100619_Biogas Digest vol 1 (Printable PDF)
Thus, biogas technology can substancially contribute to conservation and development, if the
concrete conditions are favorable. However, the required high investment capital and other
limitations of biogas technology should be thoroughly considered.
The Costs of Biogas Technology
An obvious obstacle to the large-scale introduction of biogas technology is the fact that the
poorer strata of rural populations often cannot afford the investment cost for a biogas plant.
This is despite the fact that biogas systems have proven economically viable investments in
many cases.
Efforts have to be made to reduce construction cost but also to develop credit and other
financing systems. A larger numbers of biogas operators ensures that, apart from the private
user, the society as a whole can benefit from biogas. Financial support from the government
can be seen as an investment to reduce future costs, incurred through the importation of
petrol products and inorganic fertilizers, through increasing costs for health and hygiene and
through natural resource degradation.
Fuel and Fertilizer
In developing countries, there is a direct link between the problem of fertilization and
progressive deforestation due to high demand for firewood. In many rural areas, most of the
inhabitants are dependant on dung and organic residue as fuel for cooking and heating.
Such is the case, for example, in the treeless regions of India (Ganges plains, central
highlands), Nepal and other countries of Asia, as well as in the Andes Mountains of South
America and wide expanses of the African Continent. According to data published by the
FAO, some 78 million tons of cow dung and 39 million tons of phytogenic waste were burned
in India alone in 1970. That amounts to approximately 35% of India’s total
noncommercial/nonconventional energy consumption.
The burning of dung and plant residue is a considerable waste of plant nutrients. Farmers in
developing countries are in dire need of fertilizer for maintaining cropland productivity.
Nonetheless, many small farmers continue to burn potentially valuable fertilizers, even
though they cannot afford to buy chemical fertilizers. At the same time, the amount of
technically available nitrogen, pottasium and phosphorous in the form of organic materials is
around eight times as high as the quantity of chemical fertilizers actually consumed in
developing countries. Especially for small farmers, biogas technology is a suitable tool for
making maximum use of scarce resources: After extraction of the energy content of dung
and other organic waste material, the resulting sludge is still a good fertilizer, supporting
general soil quality as well as higher crop yields.
Public and Political Awareness
Popularization of biogas technology has to go hand in hand with the actual construction of
plants in the field. Without the public awareness of biogas technology, its benefits and
pitfalls, there will be no sufficient basis to disseminate biogas technology at grassroots level.
At the same time, awareness within the government is essential. Since impacts and aspects
of biogas technology concern so many different governmental institutions (e.g. agriculture,
environment, energy, economics), it is necessary to identify and include all responsible
government departments in the dissemination and awareness-raising process.