Proceedings World Bioenergy 2010

Figure 1: The net income as function of biomass to
pulpwood volume ratio at different energy wood prices in
the pine stands.
Figure 2: The net income as function of biomass to
pulpwood volume ratio at different energy wood prices in
the spruce stands.
Figure 3: The net income as function of biomass to
pulpwood volume ratio at different energy wood prices in
the birch stands.
The analyses of which the results are based on are
somewhat simplified, e.g. the same operative coefficients
were used for both systems which in practice probably
differ between usage of different technology. For
example, accumulating felling heads have less
sophisticated components and functions and would
probably have less time reduction due to work delays
compared to accumulating processing heads. Further, the
forwarding work in the energy wood system (full trees)
was based on data for pulpwood forwarding. In practice
the differences in productivity could probably differ
somewhat more, especially at longer forwarding
distances, since the payloads at energy wood forwarding
are lower than pulpwood loads. However, we believe the
data and assumptions used in the analyses are adequate
and gives a reasonable comparison of the two systems.
5 CONCLUSIONS
The available volumes of biomass for energy in early
thinning are considerately higher compared to pulpwood
volumes. With current market prices the gross income of
the energy wood is higher even in stands containing trees
with a relative high proportion of pulpwood. The net
income becomes higher in the energy wood system
compared to pulpwood when using conventional
machinery. If the market prices for energy wood
increases with 30% (compared to the current level)
harvesting for energy wood in early thinnings could
generate a considerable income for the forest owner.
ACKNOWLEDGEMENTS
This study was financed by the Forest Power project
which is a part of the Botnia-Atlantica program.
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