Proceedings World Bioenergy 2010

Figure 2: Marginal cost curves for the harvesting of slash
and stumps from regeneration fellings in Sweden,
cumulative values (SEK/ODT as a function of million
ODT/year).
3.3 Regional marginal costs for slash with system 1
The amount of slash that could be harvested up to a
certain cost (SEK/ODT) varies for the different regions
that have been studied. Marginal costs were lowest in
South Sweden. The costs rose rapidly with increasing
distance to the industry. In South Sweden 90% of the
harvestable potential could be harvested for a cost up to
800 SEK/ODT (Figure 2). For the north of Sweden two
different pictures were given. To harvest 90% of the
harvestable potential it would cost up to 950 SEK/ODT in
the coastal area of Upper Norrland and ca. 1100 SEK/ODT
in Upper Norrland Lappland (Figure 3).
Figure 3: Marginal cost curves for the harvesting of slash
from regeneration fellings in Upper Norrland and South
Sweden, cumulative values (SEK/ODT as a function of
million ODT/year).
3.4 Regional marginal costs for stumps
As expected marginal cost curves for stump
harvesting start a higher cost level. In South Sweden to
harvest 50% of the harvestable potential would cost up to
ca. 900 SEK/ODT while at the coastal area of Upper
Norrland and at Upper Norrland Lappland the cost would
be 1100 and 1300 SEK/ODT respectively (Figure 4).
Figure 4: Marginal cost curves for the harvesting of
stumps from regeneration fellings in Upper Norrland and
South of Sweden, cumulative values (SEK/ODT as a
function of million ODT/year).
Chipping slash in the industry proved to be more
economical than chipping it at the roadside and
transporting it to the industry. In the Lappland area of
Upper Norrland the decrease in SEK/ODT was 5.5%
while in the coastal area of Upper Norrland and in South
Sweden the decrease was 4.5% and 3.5% respectively
(Figure 5)
Figure 5. Marginal cost curves for the harvesting of slash
from regeneration fellings in Upper Norrland and South
Sweden with a) a slash supply system based on chipping
at roadside (uppermost line in each region) and b) a
system based on chipping in the industry (lower line on
each region). Cumulative values (SEK/ODT as a function
of million ODT/year).
4 DISCUSSION AND CONCLUSIONS
Bioenergy systems are characterized by negative
economies of scale; as demand increases, the average
transport distance increases. This it is especially
pronounced where CHP plants are located close to the
coast (raw material supply area half circle). Localization
of CHP plants is mainly near bigger cities with an
existing district heating distribution network and a great
demand for heat. In this way a lot of electricity can be
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