Page 234 - Materials Chemistry, Second Edition

Comparing Various Indicators for the LCA 223

and to the use of fossil energy (Huijbregts et al. 2006). Indeed, the burning of fossil
fuels has many adverse impacts, on climate, health, and the ecosystem. Therefore,
decreasing fossil energy use during production of PV systems will decrease the
impact of all of these factors (Mohr et al. 2009).

3.4.2 Influence of the Used EI 99 Perspective

When comparing the three different EI 99 perspectives, the results for the Indi-
vidualist perspective stand out (Fig. 7). According to the Individualist perspective,
the high amount of mineral extraction necessary for the production of PV systems
is so important that other impact factors become negligible. The Individualist
assigns high scores to CdTe (3,764 points) and a-Si (3,020 points).
The very high scores attributed to mineral extraction by the Individualist are
due to the different ways by which resource depletion is normalized in the EI 99
method. The Individualist does not take into account the increasing energy
intensity of fossil fuel depletion. This has as a consequence that all resource
depletion impact is caused by mineral extraction. The view of the individualist
seems rather extreme. It is hard to believe that one would find the depletion of
fossil fuels to be of no importance. More and more evidence is emerging that the
energy needed to extract fossil fuels is increasing. The increasing interest in oil
from tar sands and shale gas is an indicator of this fact.
In the Hierarchist and Egalitarian perspectives, on the other hand, resource
depletion includes mineral extraction and fossil fuel use. As Fig. 7 shows, this
difference in opinion about fossil energy has a big effect on the normalization of
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resource depletion as a whole.

Fig. 7 Comparison of the EI 99 perspectives for 3 kWp PV systems (Ecoinvent v2.0)

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More details on how these high figures for the EI 99 individualist perspective come about can
be found in the literature Laleman et al. (2011).