bw_timex: A Python Package for Time-Explicit Life Cycle Assessment

The Journal of Open Source Software, vol. 11, pp. 9621

Abstract

bw_timex is a Python package for time-explicit Life Cycle Assessment (LCA).Unlike conventional LCA, time-explicit LCA allows the quantification of environmental impacts of products and processes over time, considering their temporal distribution and evolution.As such, bw_timex enables simultaneously accounting for:• the timing of processes throughout the supply chain (e.g., end-of-life treatment occurs 20 years after production), • variable and/or evolving supply chains and technologies (e.g., increasing shares of renewable electricity or higher process efficiencies in the future), and • the timing of emissions (enabling dynamic characterization).To achieve this, bw_timex uses graph traversal to convolve process-relative temporal distributions through the supply chain.From the resulting timeline of technosphere exchanges, Life Cycle Inventories (LCIs) are automatically linked across time-specific background databases.The resulting time-explicit LCI reflects the current technology status within the product system at the actual time of each process.Moreover, bw_timex preserves the timing of emissions, enabling both dynamic and static Life Cycle Impact Assessment.

Authors 3

1. Timo Diepers Aachen Institute of Technical Thermodynamics

   RWTH Aachen University

   Affiliation as printed

   Institute of Technical Thermodynamics (LTT), RWTH Aachen University, Germany

2. Amelie Müller Aachen Institute of Environmental Sciences (CML)

   Leiden University · Flemish Institute for Technological Research

   Affiliation as printed

   Flemish Institute for Technology Research (VITO), EnergyVille, Belgium

   Institute of Environmental Sciences (CML), Leiden University, The Netherlands

3. Arthur Jakobs

   Paul Scherrer Institute

   Affiliation as printed

   Technology Assessment Group, Laboratory for Energy Analysis, Center for Nuclear Engineering and Sciences & Center for Energy and Environmental Sciences, Paul Scherrer Institut (PSI), Villigen PSI, Switzerland