Perceived uncertainties of characterization in LCA: a survey
- PDF / 848,210 Bytes
- 13 Pages / 595.276 x 790.866 pts Page_size
- 90 Downloads / 175 Views
UNCERTAINTIES IN LCA
Perceived uncertainties of characterization in LCA: a survey Yuwei Qin 1 & Stefano Cucurachi 2 & Sangwon Suh 3 Received: 11 April 2019 / Accepted: 23 June 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Purpose Uncertainty analyses in life cycle assessment (LCA) literature have focused primarily on the life cycle inventory (LCI) phase, but LCA experts generally agree that the life cycle impact assessment (LCIA) phase is likely to contribute even more to the overall uncertainty of an LCA result. The magnitude of perceived uncertainties in characterization relative to that in LCI, however, has not been examined in the literature. Here, we use the pedigree approach to gauge the perceived uncertainty in the characterization phase relative to the LCI phase. In addition, we evaluate the level of approval on the pedigree approach as a means to characterize uncertainty in LCA. Methods Applying the Numeral Unit Spread Assessment Pedigree (NUSAP) approach to environmental risk assessment literature, we extracted the criteria for evaluating the uncertainty in the characterization phase. We used expert elicitation to identify a pool of experts and conducted a survey, to which 47 LCA practitioners from 12 countries responded. In order to reduce personal biases in perceived geometric standard deviation (GSD) values, we used two reference questions on weight and life expectancy at birth for calibration. Results Nearly half (49%) of respondents expressed their approval to the pedigree matrix approach as a means of characterizing uncertainties in LCA, and responses were highly sensitive to the respondent’s familiarity with the pedigree matrix. For instance, respondents who are highly familiar with the pedigree matrix were more polarized, with 15% and 19% of them expressing either strong approval or strong disapproval, respectively. Respondents less familiar with the pedigree approach were generally more favorable to its use. Compared with LCI, variability in characterization factors was influenced more strongly by geographical correlation and reliability of the underlying model, which showed 11 to 16% larger average GSDs when compared with the comparable criteria for LCI. Conversely, temporal correlation criterion was a less significant factor in characterization than in LCI. Conclusions and discussion Overall, survey respondents viewed LCIA characterization as only marginally more uncertain than LCI, but with a wider variability in responses on characterization than LCI. This finding indicates the need for additional research to develop more thorough methods for characterizing uncertainties in life cycle impact assessment that are compatible with the uncertainty measures in LCI. Keywords Uncertainty analysis . Impact assessment . Characterization factor . Life cycle assessment . Pedigree approach
Communicated By Ralph K. Rosenbaum Electronic supplementary material The online version of this article (https://doi.org/10.1007/s11367-020-01787-9) contains supplementary material, which
Data Loading...
