Scientific Programme

Scope:

The theme for the 23rd SETAC Europe LCA Case Study Symposium is Life Cycle Assessment for decision support.

The focus of these two days is on case studies that highlight both solutions and challenges when applying consequential modelling for comparisons of products, projects, and strategies. The various sessions of the scientific programme cover all aspects of the application of LCA to decision making in business practice, environmental product declarations, due diligence, social responsibility, environmental management, and policy development.

The programme consists of 6 plenum sessions on the topics detailed below, each composed of 7 oral presentations and around 45 minutes for a moderated plenum discussion. There will be no parallel sessions. This year a new concept for poster sessions will be put in place: Posters will be produced, reviewed and presented electronically; symposium participants can view posters in advance of the symposium and choose (by prioritised web-reservation) which posting presenters they wish to interact with during the posting sessions that takes place each day during the lunch break.

Session topics:

  • Consequential modelling in policy-making, Input-Output databases, and economic models
  • Marginal suppliers and temporal aspects of consequential LCI modelling
  • Views on consequential EPDs and PCRs
  • Co-product substitution and other aspects of consequential LCI modelling
  • Model uncertainty and quality assurance in LCA
  • Challenges for teaching consequential LCA and communication of results

Detailed description of session topics:

This session includes examples and case studies of how consequential LCA models are used for policy applications. Case studies use economic data and models, including Input-Output databases, integrating also with e.g. physical energy system models, to study the consequences of policy options, subsidies, and taxes on, e.g., energy production or for stimulating recycling or changes in diets.

The ambition of consequential LCI modelling is to include unit processes to the extent that they change as a consequence of a decision. This is reflected how unit processes are linked into product systems based on the expected reactions to changes in supply and demand. This session includes examples of consequential electricity mixes and models for determining market boundaries and regional detail in the identification of marginal suppliers. The session also provides examples of the inclusion of temporal differentiation, scenarios, and dynamic modelling aspects.

Product Category Rules (PCRs) are used to standardise the way Environmental Product Declarations (EPDs) are made for specific product groups. EPDs are in turn used by customers to make a choice between products within – and sometimes between – these product groups. Because EPDs influence consumer behaviour – and which of the competing products will consequently be produced – it is essential that the information conveyed by EPDs is comparable for comparable products and that PCRs are non-overlapping and defined in a consistent manner. Consequential modelling appears to offer some much-needed solutions to this, but it has also been argued that there are many barriers to be overcome for a consequential EPD scheme. In this session, we involve the participants in an investigation into the benefits and challenges of using consequential modelling and databases for an EPD scheme.

This session includes examples and case studies of how by-products are dealt with in consequential modelling, using empirical data to model the consequences of changes in by-product volumes as a consequence of a decision. Examples include metals, chemicals, food products, and food waste. The session also includes examples accounting for how rebound effects and other secondary consequences may be included in an LCI model.

LCA modelling involves the linking of unit processes into product systems (and the subsequent linking of elementary flows to impacts through environmental mechanisms), and therefore implies additional model uncertainty beyond the data uncertainty of the individual unit processes and environmental mechanisms. This session includes case studies and examples that estimate this model uncertainty for consequential models, especially the variation of and the probability of shifts between possible marginal activities.

Teaching and communicating consequential modelling involves several conceptual challenges, such as shifting between average and marginal mind-sets and different social responsibility frameworks, as well as challenges of cross-disciplinary data acquisition and computation. In this session we involve the participants in an investigation into the options for overcoming these challenges.