Project

Increasing robustness of LCAs

Life Cycle Assessment (LCA) is a well-established method for assessing the potential environmental impacts associated with a product or service system. SETAC (Society of Environmental Toxicology and Chemistry) played a key role in synchronizing the LCA framework, the terminology and the methodology during the period 1990 to 2000. ISO (International Organization for Standardization) produced in the meantime two international standards for the methods and procedures used in LCA: ISO 14040 and 14044. The LCA method is standardized, but not in detail, leaving room for a range of methodological choices.

LCAs of the same product or comparisons between products should results in the same outcome. In  practise, however,  they could provide different and sometimes even conflicting results . This is not very beneficial for the credibility of LCA as a decision support tool.

Discrepancies in LCA results can be due to uncertainties. Uncertainties in LCA results have been recognized and acknowledged for a long time. Sensitivity analysis, which is recommended by ISO, can be used to assess the uncertainty.

Aim of the project

The purpose of the study is to increase the robustness of the LCA outcome. Robustness means in this study: a consistent outcome of the LCA results regardless of the used data sets and methods. The first step in the study is to identify those  topics in the LCA procedure which are not fully crystallized and can lead to discrepancies in the LCA outcome. Next, a new approach (a combination of sensitivity analysis and ensemble modelling) will be constructed. This new approach will be used in (comparative) LCAs. The goal is to provide a new approach to increase the robustness of the LCA results and thus make the results more trustworthy as a decision support tool. The study focusses on beverage packaging material as a  case study.

Method

  • A review of existing LCA studies on disposable beverage cups in order to identify issues which can lead to discrepancies in LCA results.
  • The construction of a new approach which includes the use of multiple data sets and multiple modelling choices. The approach will be tested on a single product system: a disposable polystyrene cup.
  • The use of the new approach in a comparative LCA. The fossil fuel based polystyrene cup will be compared with two compostable cups: the polylactic acid (PLA) cup and a paper cup with a bio-plastic liner.
  • A review of existing methods to model recycling in LCA studies. The different methods will be compared using two case studies.

Results

E. van der Harst and J. Potting (2013). A critical comparison of ten disposable cup LCAs. Environmental Impact Assessment Review 43 . - p. 86 - 96.

E. van der Harst and J. Potting (2013). Spread in LCA results from using multiple data sets and modelling choices: A case study of PS disposable cups. In: Proceeding of the 6th International Conference on Life Cycle Management, 25-28 of August, Gothenburg, Sweden.

E. van der Harst and J. Potting (2014). Variation in LCA results for disposable polystyrene beverage cups due to multiple data sets and modelling choices. Environmental Modelling & Software 51 (2014).  p. 123 - 135.