Methods 4: Towards Improved Comparability

The papers presented in this session consider several different aspects of LCA – from reducing the geographical uncertainty of data from Ecoinvent; through tools for improved dissemination of LCA studies, product comparison with additional consideration of usefulness and user appreciation, and life cycle sustainability assessment for supply-chain decision making; to the development of a method of assessing impacts in terms of the finite capacity of the planet. These papers will improve the comparability of results from studies based on LCA methodology, with the last calling into question the value of comparing such results solely with the impacts of other human activities.

Key Discussion Points:

  1. Is enough detailed geographical information available for most LCA studies to enable geographically disaggregated data to be used?
  2. Input-output is a top-down approach. Process-based is a bottom-up approach. What are the limitations of combining two datasets from these two different approaches?
  3. How can a tool allowing evaluation of results sufficiently disguise confidential information from back calculation?
  4. How does the multi-attributional analysis presented by Kuei-Yuan compare to existing life cycle sustainability assessment methodologies?
  5. Should more studies be applying LCSA methodologies rather than LCA?
  6. If a Planetary Boundaries approach allows for impacts to be considered in absolute terms, how can we assess the significance of these impacts without reference to other human activities? And if we’re going back to comparison with other human activities, why is this approach an improvement on existing ones?
15:30 Chris Mutel and Xun Liao

Automatic differentiation of global datasets using input-output data

ABSTRACT. Version 3.1 of the ecoinvent database [1] has between 5430 and 5870 activities with the location “rest of the world” or “global”, depending on the system version. In this presentation, we first show how important these activities are, using contribution analysis and a variety of impact assessment methods. We then describe a simple model to disaggregate these activities to a finer spatial scale using data from the CREEA [2] input output database. Our objective is to regionalize the supply chain without excessive data collection.

Our first step is to understand what is meant by “rest of the world”. This location is dynamically defined as everywhere not covered by a local dataset. We developed an open source library to map these dynamic regions for ecoinvent [3], and briefly illustrate its usage.

Both ecoinvent and CREEA identify activities using ISIC codes. We match these codes across both databases, using the most specific data available. We then use the region-specific CREEA production amounts to disaggregate ecoinvent processes to a finer spatial scale. The CREEA values act as allocation factors, and are normalized to sum to one. In contrast to most input-output databases, CREEA values are given in units of mass, not monetary value. Finally, inputs in the disaggregated activities are linked to local markets whenever possible. We illustrate the differences in regionalized LCA scores using the LC IMPACT method [4] for both database versions.

Although our case study cannot prove that such geographic disaggregation will reduce total system uncertainty, such a reduction in uncertainty is expected. Geographic disaggregation can also improve the interpretation of LCA results, showing the origin and trade patterns of environmental impacts, and selecting key regions and technologies for avoidance or improvement.

This presentation was supported by SCCER Supply of Electricity.

[1] Weidema, Bo Pedersen, et al. Overview and methodology: Data quality guideline for the ecoinvent database version 3. Swiss Centre for Life Cycle Inventories, 2013. [2] [3] [4]

15:45 Joseph Millogo and Kuei-Yuan Chan

A Multi-Attributes Analysis Considering Products’ Environmental Impacts under Uncertainty

ABSTRACT. Product purchasing decision-making requires not only customers’ preferences, but also insightful performance metrics to ensure fair justifications are made. With the advancement of technology and the thriving social awareness, the number of factors on the choice of a product is increasing. Ideally, a product should be green, useful, and appreciated by users. Although the complexities involved in product comparison are yet to be fully understood through scientific investigation, we believe providing transparent product data is a way to help customers and product manufacturers select their ideal products, especially in the presence of uncertainties. In an attempt to scientifically compare two products, this paper proposes a method with three filters to measure how well a product performs in the aforementioned three dimensions. The first filter is based on the life cycle assessment (LCA) to estimate the environmental impacts associated to a product’s lifecycle to which the concept of mini-LCAs is added. The second filter considers technology and efficiency to determine how well a product performs its functions. The third filter uses a survey-based analysis to obtain customers’ preferences under uncertainties. In our method each filter provides not only grades based on which product comparison can be done, but also an index to show the degree of certainty, or uncertainty. Results from campus-wide surveys show the effectiveness of the proposed method in justifying each product.

16:00 Marwa Bassam Hannouf and Getachew Assefa Wondimagegnehu

Comparing Methods of Integrating Environmental, Economic and Social Dimensions of Life Cycle Sustainability Assessment

ABSTRACT. Growing environmental awareness and stringent environmental regulations are urging companies to look for sustainable opportunities in their supply chain (SC) that reduce environmental impacts while achieving economic and social benefits [1,2]. This interrelationship between the three dimensions of sustainability is addressed in the life cycle sustainability assessment (LCSA) methodology [3-6]. However, LCSA is still faced with the difficulty of integrating the three components of sustainability [6] for different types of LCSA methodologies (consequential, lead firm and educative). There are LCSA studies that have made efforts to help meet this challenge [e.g.7-13]. This review lays the foundation for a PhD project on developing a decision-making approach using LCSA that can guide large greenhouse gas emitters in Alberta, Canada develop sustainable strategies along their SC.

In light of the recent developments in LCSA, new approaches and methods proposed for the integration of environmental, economic and social dimensions of LCSA are reviewed [7-13] with the objective of identifying their strengths and weaknesses. A systematic comparison between these methods is made, focusing on the following factors: – Objective – Inventory indicators and categories for each dimension – Impact assessment method for each dimension – Aggregation procedure for the results of the three dimensions – Results presentation in decision-making – Outcome – Case study product systems

The review indicates that these frameworks have succeeded to integrate the three dimensions of sustainability and present the LCSA results. Yet, these approaches need further improvements. There are data quality, aggregating, and weighting issues that could increase uncertainty and subjectivity of LCSA results. In the reviewed approaches, not all relevant indicators, especially qualitative social indicators, were considered. Most of these approaches were examined for one or two case studies, making the implications difficult to generalize. Current approaches proposed were only applicable to consequential LCSA in order to compare sustainability performance of alternatives. There is still lack of lead firm LCSA approaches which evaluate the sustainability performance of companies and identify possible areas of sustainability improvements, targeting their processes.

By pointing out the strengths and limitations of LCSA methods and highlighting areas that call for new contributions, this work helps advance the development of this emergent field.


1. Ashby A., Leat M., Hudson-Smith M., 2012. Making connections: a review of supply chain management and sustainability literature. Supply Chain Management: An International Journal, 17(5), 497-516.

2. Beske, P., Seuring, S., 2014. Putting sustainability into supply chain management. Supply Chain Management: An International Journal, 19(3), 322-331.

3. Zamagni Alessandra, 2012. Life cycle sustainability assessment. International Journal of Life Cycle Assessment, 17, 373-376.

4. Valdivia, S., Ugaya, CML., Sonnemann, G., &Hildenbrand, J. (eds.), 2011. Towards a life cycle sustainability assessment. Making informed choices on products. ISBN: 978-92-807-3175-0 Paris 2011. Retrieved from

5. United Nation Environment Program, UNEP/SETAC, 2011. Towards life cycle sustainability assessment: Making informed choices on products, Retrieved from

6. Valdivia S., Ugaya C.M.L., Hildenbrand J., Traverso M., Mazijm B., Sonnemann G., 2013. A UNEP/SETAC approach toward a life cycle sustainability assessment – our contribution to Rio+20. International Journal of Life Cycle Assessment, 18, 1673-1685.

7. Traverso M., FinkbeinerM., Jorgensen A., Schneider L., 2012a. Life cycle sustainability dashboard. Journal of Industrial Ecology, 16(5), 680-688.

8. Traverso M., Asdrubali F., Francia A., Finkbeiner M., 2012b. Toward life cycle sustainability assessment: an implementation to photovoltaic modules. International Journal of Life Cycle Assessment, 17, 1068-1079.

9. Basurko O.C., Mesbahi E., 2014. Methodology for the sustainability assessment of marine technologies. Journal of Cleaner Production, 68, 155-164.

10. Foolmaun, R.K. and Ramjeawon, T., 2012. Life cycle sustainability assessments (LCSA) of four disposal scenarios for used polyethylene terephthalate (PET) bottles in Mauritius. Environmental Development Sustainability, 15, 783-806.

11. Finkbeiner, M., Schau, E.M., Lehmann, A., Traverso, M., 2010. Towards life cycle sustainability assessment. Sustainability, 2, 3309-3322. doi:10.3390/su2103309

12. Vinyes E., Oliver-Sola J., UgayaC., Rieradeyall J., Gasol C.M., 2013. Application of LCSA to used cooking oil waste management. International Journal of Life Cycle Assessment, 18, 445-455.

13. Zhang, H., Haapala, K.R., 2014. Integrating sustainability manufacturing assessment into decision making for a production work cell. Journal of Cleaner Production, 1-12.

16:15 Roland CliftJonathan ChenowethIan ChristieJulie ClavreulHenry KingRichard Murphy and Sarah Sim

Planetary Boundaries as a basis for introducing absolute limits into strategic sustainability assessment.


“Sustainability” refers to the imperative to provide a decent quality of life for all humanity in perpetuity, within the constraints imposed by a finite planet. Currently, Life Cycle Assessment gives insufficient recognition to ecological limits: the environmental impacts of providing a product or service are, at best, assessed by normalising them against other human activities. Whilst this approach is helpful in informing choices between product formats and innovations (i.e. to answer the question ‘which is better?’) and for identifying life cycle hotspots, it is too limited to indicate how (un)sustainable the impacts are in absolute terms.

This paper outlines the initial stages of development of an approach to setting LCA-based targets for sustainability, recognising the finite capacity of the planet. It is based on the work of Steffen et al. [1] and Rockström et al. [2], who introduced an approach to defining and potentially quantifying ecological constraints, in terms of “Planetary Boundaries”. The Planetary Boundaries approach has been much discussed, but the focus in this contribution is on how it might be implemented in LCA, to set performance targets related to exogenous limits on resource availability or ecological resilience. The approach is explored for four of the boundaries – climate change, biodiversity, novel entities and water use –illustrating the challenges in developing the Planetary Boundaries approach into an operational tool.

As a specific application, the implications are explored of using Planetary Boundaries as targets for company innovation strategy and decision-making by a large multinational company in the Fast-Moving Consumer Goods (FMCGs) sector – Unilever. A number of fundamental issues must be addressed, including geographical localisation, quantification of some limits and equitable sharing of the available “ecological space”.

References 1. Steffen, Will et al. (2015) “Planetary boundaries: Guiding human development on a changing planet”, Science 347 (6223), 736-747. 2. Rockström, Johan et al. (2009) “A safe operating space for humanity”, Nature 461, 472-475.