Normalization and weighting: the open challenge in LCA

Drawing the correct conclusions based on environmental indicators can be challenging due to the consideration of a broad variety of environmental impacts, which might show diverging results. Many life cycle assessment (LCA) practitioners seek help in interpreting disparate results of life cycle impact assessment (LCIA) in different impact categories by applying normalization and weighting. The standards of the International Organization for Standardization (ISO) do not support the use of normalization and weighting for publishing comparative assertions in LCA. Nevertheless, the increasing need for identifying the most relevant impact categories as well as obtaining unequivocal results have led to further research on normalization and weighting, including the calculation of single scores. The 72nd LCA Forum focused on the present state of normalization and weighting in LCA. Statements in ISO 14040, such as those concerning internal and external normalization and hints regarding interpretation, were considered part of the baselines. The forum provided a platform for discussing ongoing developments in the technical specifications for this theme (ISO/TS 14074). In particular, the forum focused on new approaches and ways to boost the acceptance of the use of normalization and weighting and the communication of single scores by a broader community. The current status and main challenges of normalization and weighting were presented in the first session (Section 2). The speakers of the second session showed how normalization and weighting can be applied to the Product Environmental Footprint (PEF), and how different normalization and weighting schemes may impact the final results (Section 3). In the third session, the speakers presented some promising developments in normalization and weighting (Section 4), while decision-making implications of using single scores were discussed in the last session (Section 5).

ANDREAS Roesch;  SALA Serenella;  JUNGBLUTH Niels; 

2020-11-17

SPRINGER HEIDELBERG

JRC121391

0948-3349 (online),   

https://link.springer.com/article/10.1007/s11367-020-01790-0,    https://publications.jrc.ec.europa.eu/repository/handle/JRC121391,   

10.1007/s11367-020-01790-0 (online),