Life-Cycle-Assessment for Stoves and Ovens - ESU-services Ltd.

3 Impact Assessment
In this chapter the results of the life-cycle assessment for the various cooking alternatives investigated
are presented and analyzed. The classification used is explained. Firstly all alternatives
are compared. The influence of the efficiency on the environmental impact scores and
the values for the Eco-indicator 95+ are investigated in detail. This is followed by a more detailed
analysis of the results for the calculation of Eco-indicators 95+ and the contribution of
different stages in the life-cycle for the total results. The results of the calculation for Ecoindicators
95+ are shown in Tab. 22 of annex 6.2. The impact score profile is given for 23 environmental
impact categories in annex 6.2, Tab. 23. The results of the life-cycle-inventoryanalysis
for all environmental impacts investigated are given in Annex 6.5, Tab. 24.
3.1 Categories for the Impact Assessment
There are different concepts to conduct the impact assessment in an LCA. They can be distinguished
in fully and partly aggregated models. A good overview for the state of the art is
given for example by Braunschweig et al. (1996). (Heijungs et al. 1992a) developed a concept
for the classification of different environmental impacts to impact categories. Developing the
concept for the Eco-indicator 95, Goedkoop (1995) improved and extended this approach. A
description of this method is given in annex 6.1. Tab. 14 shows the effects distinguished in
the two reports.
Twenty-three categories of environmental impact categories are distinguished in the calculation
with ECOINVENT. These impact categories describe different environmental hazards or
problems often considered while discussing about environmental themes, e.g., global warming,
use of resources, etc. But some of these categories describe effects overlapping because
they where adopted from different methods or they describe the same effect in a different
time horizon. The third column of Tab. 14 gives the effects implemented in the database
ECOINVENT. The last column of the table gives a short description of the different environmental
impacts.
For this report the calculation of Eco-indicators 95 for nine environmental impacts as described
in annex 6.1 has been implemented in the database ECOINVENT. The advance for
the implementation is described in the Annex 6.2. The inclusion is linked with a few changes
of the original method. This approach is used for evaluation in this report and named as Ecoindicator
95+. Except pesticides 21 , environmental effects as distinguished by Goedkoop
(1995), are included in this approach.
But the method Eco-indicator 95+ does not give a good picture of all environmental impacts
of electricity production based on hydro- and nuclear power in Switzerland and therefore
yields to misleading results.
Thus the actual investigation will look on some additional impact categories calculated in
ECOINVENT and not included in the concept of Eco-indicator 95+. The impact categories
radioactivity, space use, waste heat (as an indicator for the use of energy resources) and eoctoxicity
are used for the valuation. The Eco-indicator 95+ does not give a picture of the first
three effects. Waste heat might not be as important for the environment, but this impact category
is used here as an indicator for non-renewable energy resources. Some heavy metals do
21 Up to now, pesticides were not included in the database ECOINVENT because they do not play a role for the
processes investigated so far.
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