Addressing temporal considerations in life cycle assessment

Didier Beloin-Saint-Pierre (1) , Ariane Albers (2) , Arnaud Hélias (3) , Ligia Tiruta-Barna (4) , Peter Fantke (5) , Annie Levasseur (6) , Enrico Benetto (7) , Anthony Benoist (8) , Pierre Collet (2)

1 Empa Materials Science and Technology - EMPA (SWITZERLAND)
2 IFPEN - IFP Energies nouvelles
3 UMR ITAP - Information – Technologies – Analyse Environnementale – Procédés Agricoles
4 TBI - Toulouse Biotechnology Institute
5 DTU - Danmarks Tekniske Universitet = Technical University of Denmark
6 ETS - Ecole de Technologie Supérieure [Montréal]
7 LIST - Luxembourg Institute of Science and Technology
8 UPR BioWooEB - BioWooEB

In life cycle assessment (LCA), temporal considerations are usually lost during the life cycle inventory calculation, resulting in an aggregated “snapshot” of potential impacts. Disregarding such temporal considerations has previously been underlined as an important source of uncertainty, but a growing number of approaches have been developed to tackle this issue. Nevertheless, their adoption by LCA practitioners is still uncommon, which raises concerns about the representativeness of current LCA results. Furthermore, a lack of consistency can be observed in the used terms for discussions on temporal considerations. The purpose of this review is thus to search for common ground and to identify the current implementation challenges while also proposing development pathways. This paper introduces a glossary of the most frequently used terms related to temporal considerations in LCA to build a common understanding of key concepts and to facilitate discussions. A review is also performed on current solutions for temporal considerations in different LCA phases (goal and scope definition, life cycle inventory analysis and life cycle impact assessment), analysing each temporal consideration for its relevant conceptual developments in LCA and its level of operationalisation. We then present a potential stepwise approach and development pathways to address the current challenges of implementation for dynamic LCA (DLCA). Three key focal areas for integrating temporal considerations within the LCA framework are discussed: i) define the temporal scope over which temporal distributions of emissions are occurring, ii) use calendar-specific information to model systems and associated impacts, and iii) select the appropriate level of temporal resolution to describe the variations of flows and characterisation factors. Addressing more temporal considerations within a DLCA framework is expected to reduce uncertainties and increase the representativeness of results, but possible trade-offs between additional data collection efforts and the increased value of results from DLCAs should be kept in mind.

Keywords: Dynamic LCA; Temporal considerations; Review; Recommendations; Implementation challenges

Domains: Environmental Engineering

Didier Beloin-Saint-Pierre, Ariane Albers, Arnaud Hélias, Ligia Tiruta-Barna, Peter Fantke, et al.. Addressing temporal considerations in life cycle assessment. Science of the Total Environment, 2020, 743, pp.140700. ⟨10.1016/j.scitotenv.2020.140700⟩. ⟨hal-02894987v2⟩