Vattenfall aB GeneRatIOn nORDIC CeRtIfIeD enVIROnmental ...

3 Environmental performance BASEd on LCA
Small-scale hydropower stations are generally so called run-of-river stations, i.e. they
have no reservoir. Small-scale hydropower is mainly located south of the river Dalälven
in watercourses that have streaming water all year round, i.e. a reservoir is not required
to maintain relatively constant generation. One of the selected power stations, Upperud,
is a small-scale power station. The absence of reservoirs means that no emissions from
inundated land occur. The net effect is considerably lower emissions of greenhouse gases
and eutrophying substances than for a station with a reservoir. Environmental impact
per kWh due to construction, reinvestment, and operation is consistently higher from
the selected small-scale hydropower station than from average large-scale hydropower
stations. Investment cost per MW and Ecoprofile go hand-in-hand.
3.3.6 Differences vs. previous EPD ® s
There are several differences between this EPD ® and previous EPD ® s for Vattenfall’s hydropower.
In the table below a comparison between the results of this EPD ® and the EPD ® for
Vattenfall’s hydropower, certified 2005 and the weighted results for the EPD ® s for the
rivers Ume älv and Lule älv, certified 2000 and 2002, is shown. Distribution of electricity
is included in this EPD ® but has been excluded here to make the values comparable with
the earlier EPDs.
Emissions of
Unit
Vattenfall´s
Nordic hydropower
2008
(incl. distribution)
Vattenfall´s
Nordic hydropower
2005
(excl. distribution)
Weighted results
for EPD
Ume älv 2000 and
Lule älv 2002
(excl. distribution)
Greenhouse gases g CO 2 -q. 4,5 4,2 4,9
Ozone-depleting
gases
Acidifying
substances
Gases contributing
to the formation of
ground-level ozone
Eutrophying
substances
g CFC-11-q. 3,3 . 10 -8 3,8 . 10 -8 9,0 . 10 -9
g SO 2 -eq. (Mol H + ) 4,6 . 10 -3 9,8 . 10 -3 (3,1 . 10 -4 ) 4,5 . 10 -3 (1,4 . 10 -4 )
g ethene-eq. 8,4 . 10 -4 6,6 . 10 -4 4,7 . 10 -4
g PO 4 3- -eq. (g O 2 ) 4,9 . 10 -2 4,6 . 10 -2 (2,1) 5,9 . 10 -2 (2,7)
Oil to water g 2,5 . 10 -4 5,0 . 10 -5 5,0 . 10 -5
Oil to water from
core process alone
g 4,1 . 10 -5 4,2 . 10 -5 4,2 . 10 -5
The main contributions to the emission categories in the table above are cause in the construction
phase of the hydropower stations. Operation causes small emissions. Used selected generic
data for production of electricity, material, and fuels, have been updated between the EPD ® s.
Newer data tend to have tend to have fewer data gaps resulting in a higher impact.
Another trend is that newer data mirror newer processes that actually have a lower environmental
impact, like for instance the copper industry, which considerably has reduced
its sulphur emissions.
Concerning emissions of oil to water in the Core process, the hydropower stations, a
weak positive trend can be seen since 2005. Systematic environmental efforts have been
made: improved supervision systems, investments in new technology containing smaller
quantity of oils, installation of oil separation etc. The comparison with the weighted value
from 2003 limps since that EPD ® only comprises the rivers Ume älv and Lule älv.
Following comparison concerns the difference between the two latest EPD ® s: EPD ® for
Vattenfall´s Nordic hydropower 2005 and the EPD ® in case. The latter EPD ® has been
carried out according to a later PCR with changed regulations.
© Vattenfall AB Generation Nordic 2008
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