In principle, there are published standards for life cycle assessments (LCA) that provide guidance on how to compare different polymers fairly with regard to their environmental impacts. However, the rules still leave sufficient room for manoeuvre to specify the methods by which such comparisons are to be carried out in LCA1.
The fact that there is still a need for more far-reaching, coordinated rules is shown by the ongoing activities on the “Product Environmental Footprint” and in particular by the activities of the Joint Research Center (JRC) on bio-based polymers. The overall objective of these activities is to elaborate on a consistent and appropriate LCA-based method for the purpose of a “Comparative Life-Cycle Assessment of alternative feedstock for plastics production”, including a number of case studies (JRC 2018). The final report is expected by end of the year or early 2020.
Michael Carus, main author of this text, was invited to the stakeholder workshop “Comparative Life-Cycle Assessment of alternative feedstock for plastics production” (29 & 30 November 2018 in Brussels). During the workshop there were many discussions, most of which concerned methodological-technical aspects. These were taken up by the JRC experts and will be considered for the further development. Experts from European Bioplastics have also made further submissions in this regard. In this document, we want to focus on the rather fundamental problems that make a fair comparison hardly possible, and which can often be solved only with difficulty and incompletely, both methodically and technically.
Nevertheless, after having discussed these fundamental problems, we make a proposal on how the problems could be dealt with in the most targeted way possible. We hope that our suggestions can still find their way into the final JRC paper.
Read the letter at www.bio-based.eu/ecology/#lettertoJRC
1“Although there are published standards for LCAs (ISO 14040/44, and the International Reference Life Cycle Data System (ILCD) handbook), these do not give fixed rules for calculating GHG reductions: much is left to users to select what they consider the most appropriate method in particular cases. The results often depend strongly on these choices. This is why the LCA guidelines do not offer a consistent or unambiguous way of determining carbon intensities by economic operators or by national authorities.” https://ec.europa.eu/clima/sites/clima/files/transport/ fuel/docs/novel_transport_fuels_default_values_en.pdf
Source: nova-Institut GmbH, 2019-09-04.