Page 67 - Materials Chemistry, Second Edition

62 4. Life cycle sustainability assessment: An ongoing journey

was outlined during the very early stage of development. In fact, as reported by Finkbeiner
et al. (2010), already in the last years of the 20th century, the triple bottom-line of sustainability
had been translated into several evaluation frameworks. In the early years, however, the
research community appeared unable to develop a common framework for the attribution
of a relative weighting among the three pillars of sustainability, namely environmental, eco-
nomic, and social aspects (Kl€ opffer, 2003).
Following examples provided by Finkbeiner et al. (2010), the three perspectives embodied
into LCSA has been translated by into a ternary diagram, namely the life cycle sustainability
triangle (LCST). In analogy with the geological characterization of soil textures or chemical
mixtures, in fact, any triple-parameters scheme may be evaluated. In this case, as already
outlined by Hofstetter et al. (1999), the environmental impacts, environmental, economic,
and social impacts can be visualized, based on the relative weights attributed. The represen-
tation of a hypothetical weighting set is given in Fig. 4.4 (Finkbeiner et al., 2010). The same
scheme is suggested as a valuable tool for scenarios comparison. In particular, the evaluation
of the relative weighting is accomplished by following the dominance patterns along the axes,
starting from the three corners, where each of the performance areas of evaluation (i.e.,
environmental, economic, and social) are individually rated 100%. The general rule is, evi-
dently, that the sum of the weighting factors must be equal to 100%.
A second scheme proposed by Finkbeiner et al. (2010) is the life cycle sustainability dash-
board (LCSD), as outlined by Hardi and Semple (2000) and detailed by Traverso and
Finkbeiner (2009). Fig. 4.5 reports the visualization of the LCSD, as a composition of three dif-
ferent and free-standing evaluations, separately performed over the three relevant aspects of
sustainability.
In accordance with Kl€ opffer (2003), the abovementioned scheme implies that the three pil-
lars of sustainability have to be assessed separately beforehand. Only in light of such results
can the comprehensive sustainability assessment be accomplished and, therefore, further

FIG. 4.4 Example of a weighting scheme for LCSA, as presented by Finkbeiner et al. (2010).