Vattenfall aB GeneRatIOn nORDIC CeRtIfIeD enVIROnmental ...

3 Environmental performance
BASED on LCA
3.1 Background
This EPD ® is based on a LCA on Vattenfall’s hydropower in the Nordic countries during the
reference year 2007. The declared unit is 1 kWh net electricity generated and thereafter distributed
to a customer connected to the 70/130 kV network. Resource consumption, emissions,
and waste amounts in conjunction with construction, operation and reinvestments of
power stations and dams have been inventoried. Decommissioning is excluded because of
the improbability of that scenario. The reinvestment rate has been set at a level that provides
for complete replacement of the power station during its lifetime, i.e. a fully functioning
power station will exit the system at the end of the assumed lifetime. This results in greater
environmental impact in the LCI than the alternative of including decommissioning. The level
of uncertainty in the description of the impact on biotopes is reduced, because we avoid
speculative assessments of how possible/desirable a return to unregulated flows would be,
and of the process of re-colonization from unaffected biotopes to affected ones.
3.2 System Boundaries, Allocation and Data Sources
3.2.1 System boundaries
The figure below is a simplified process tree with system boundaries for the LCA for electricity
generated in Vattenfall’s Nordic hydropower stations and distributed to the consumer.
Production of
construction
materials
Production of
raw materials
trp
trp
trp
Construction
of suppliers
factories
Construction
and
reinvestment in
dams etc.
Manufacturing
of turbine and
generator
Manufacturing
of other
components
Construction of
power networks
Upstream process
Production of operation
chemicals, oils and other
auxiliaries for operation
of hydropower plants
CORE process
Power plant
Downstream process
Losses in transmission/
distribution systems and
maintenance
1 kWh el
Decommissioning
of
suppliers
factories
Scrapped
reinvested
material
Operational
waste
Decommissioning
of power
networks
trp trp trp trp trp trp
Waste to
landfill
Waste to
recycling
Waste to
incineration
Legend
Core process
Core process – infrastructure
Upstream process
Upstream process – infrastructure
Downstream process
Downstream process – infrastructure
Not included in the analysis
Simplified process tree with system boundaries for life cycle inventory of Vattenfall´s
hydropower. Trp means transportation.
© Vattenfall AB Generation Nordic 2008
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