Fig. 3.2: Integration of a biogas plant into the
agricultural production cycle (Source:
OEKOTOP)
Table 3.7: Biogas compatibility of farm types (Source: OEKOTOP)
Type of farm
Stock farming only
Crop farming only
Mixed Agriculture
Stock farming for:
- animal power
- meat production
extensive
intensive
- milk production
Crop farming:
- vegetables
- field-tilling
unirrigated
irrigated
Characteristics of relevance to biogas
generation
Pasturing (nomadic, ranching, etc.)
Intensive stationary fattening
Crop residue only; fermentation
difficult
Rating as site for biogas
plant
unsuitable suitable
normally unsuitable
Mostly nighttime stabling; only a few
animals; 50% of dung collectible
possible
Pasturing; no stabling; dung wasted
Fattening in stables; dung directly usable
Frequently permanent stabling; all dung
and urine usable
unsuitable
suitable
suitable
Near house; crop residue and water
available year-round
possible!
1 harvest per year, scarcity of fodder,
long-distance hauling of water and manure
2-3 harvests per year; water available,
small fields
unsuitable
possible
Adding a biogas plant to an integrated agricultural production system not only helps save firewood
and preserve forests, but also contributes toward sustained soil fertility through organic fertilization
and ensures the long-term crop-bearing capacity of the soil. Work involving the dissemination of
biogas. technologies must account for and call attention to that complex relationship. If no organic
fertilizing has been done before, a biogas plant will mean more work. Organic waste has to be
collected and afterwards spread on the fields. Only if the owner is willing to invest the extra effort
can the biogas plant be expected to serve well in the long term.
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