biogaspartner – a joint initiative.

Value.Chain.of.Biomethane.
value Chain of Biomethane.
The generation of biomethane is based on a complex process
in various stages. Many factors influence the process from the
generation of biomass to the application of the fed-in biomethane
– and many diverse players have a stake in the success
of any biomethane project. The following chapter describes
the value chain of biomethane generation.
4.1.Biomass.production..
since biogas can in principle be generated from any organic
compound, the biomass feedstock that can be used to produce
biogas is diverse. some biomass feedstock comes from farms in
the form of plants. others come from other processes, or from
animals, in the form of waste materials like household garbage
and sewer sludge. Biomass suitable for use in biogas production
is called “feedstock.” Waste’s suitability for use as feedstock
brings every available organic material into question. Especially
useful for biogas generation are sewer sludge, kitchen rubbish,
and liquid manure, which as waste products are abundant and
affordable.
32 B I o G a s P a r T n E r – a j o I n T I n I T I a T I v E
Energy.plants..
The term “energy plants” refers to crops that are cultivated
especially for the purpose of energy production. These especially
include crops with high photosynthetic rates that grow
quickly in the climatic conditions of a given region. In central
Europe, such plants include corn, rapeseed, and rye. Many
tropical countries use sugarcane extensively as an energy plant.
Energy.plants.for.biogas.generation..
Maize is especially well-adapted for use in biogas facilities,
though cereals (such as rye) and/or grass cuttings are also
acceptable. The plants most suitable for use in biogas generation
vary from region to region; they must be chosen against
the background of local conditions. From a climate protection
perspective, it is important to ensure that local land use
changes associated with energy plant cultivation do not lead
to negative ecological effects.
4.2.Logistics.
With regard to the logistics of biomass energy, one must keep
in mind the energetic and economic barriers that make longdistance
delivery of feedstock impractical. Because biomass can
only be harvested during certain short periods of the year, these
barriers necessitate a well-planned biomass logistics chain.
It is necessary to distinguish between the concepts of decentral-
ised and central storage:
If the areas surrounding biogas facilities already possess the
capacity to hold the biomass that will be needed by a local
area during the year, decentralised storage may be the best
approach. In such cases, biomass is delivered to processing
facilities on a continual (“just-in-time”) basis. Through this, a
good utilisation of transport materials is achieved, with remaining
dry fermentation feedstock being transported away as
back-freight. a downside of decentralised storage is that personnel
costs may run high, since biomass must be delivered more
frequently.