8.6 Macro-economic analysis and evaluation

The main quantifiable macro-economic benefits are:

- national energy savings, primarily in the form of wood and charcoal, with the latter being valued at market prices or at the cost of reforestation

- reduced use of chemical fertilizers produced within the country.

Additionally, foreign currency may be saved due to reduced import of energy and chemical fertilizers.

Macro-economic costs incurred in local currency for the construction and operation of biogas plants include expenditures for wages and building materials, subsidy payments to the plant users, the establishment of biogas extension services, etc. Currency drain ensues due to importing of gas appliances, fittings, gaskets, paints, etc.

In addition to such quantifiable aspects, there are also qualitative socioeconomic factors that gain relevance at the macroeconomic level:

- autonomous decentralized energy supply
- additional demand for craftsmen's products (= more jobs)
- training effects from exposure to biogas technology
- improved health & hygienic conditions, etc.

Considering the present extent of biogas-plant diffusion, such effects should be viewed realistically, i.e. not overvalued. While a substantial number of biogas plants may be installed in one or more regions of a given developing country, they cannot be expected to have much impact at the national level. At the regional and local levels, however, the multipartite effects described in this subsection are definitly noticeable.