WE.1.C || Methodological Approaches to Assess Life Cycle Consequences

Rapf, Matthias; Tang, Longhan; Pekgil, Gizem; Kranert, Martin

In LCA practice, weighting and valuation of environmental impacts is strongly based on subjective impressions and decisions. This makes LCAs with similar scopes very hard to compare. We are therefore examining entropy production as physical variable to quantify environmental sustainability on a strictly scientific, inambiguous basis. While the link of entropy production to sustainability including environmental impacts has been recognised already more than a century ago, the attempts to apply this knowledge in practice has remained restricted to very narrow limits. This is mainly due to several obstacles in transferring the well-defined thermodynamic quantity to a very diverse and complex system like the environment. In our research, we try to remove these obstacles in order to show how the general idea can be substantially transferred to LCA practice. In our contribution to LCM 2021, we will show how the Entropy-LCA, quantifying the overall environmental impact of processes, can serve to make existing LCAs comparable, and to support the weighting and valuation process in future LCA practice. To do so, we will discuss methods to make this complex approach manageable, e.g. in defining appropriate balance limits, and quantifying hazardous states with the processes variable entropy production (“entropy of a hole”). In a case study about four ways of energy production, we will then show which influence the choice of methods has on the calculation results. Finally, we’ll present the state of our work in harmonising the results of our entropy balances with classical LCA studies. Our research has been funded by Vector Stiftung Stuttgart.