Rolf Frischknecht

Review of methods addressing freshwater use in life cycle inventory and impact assessment

PurposeIn recent years, several methods have been developed which propose different freshwater use inventory schemes and impact assessment characterization models considering various cause–effect chain relationships. This work reviewed a multitude of methods and indicators for freshwater use potentially applicable in life cycle assessment (LCA). This review is used as a basis to identify the key elements to build a scientific consensus for operational characterization methods for LCA.MethodsThis evaluation builds on the criteria and procedure developed within the International Reference Life Cycle Data System Handbook and has been adapted for the purpose of this project. It therefore includes (1) description of relevant cause–effect chains, (2) definition of criteria to evaluate the existing methods, (3) development of sub-criteria specific to freshwater use, and (4) description and review of existing methods addressing freshwater in LCA.Results and discussionNo single method is available which comprehensively describes all potential impacts derived from freshwater use. However, this review highlights several key findings to design a characterization method encompassing all the impact pathways of the assessment of freshwater use and consumption in life cycle assessment framework as the following: (1) in most of databases and methods, consistent freshwater balances are not reported either because output is not considered or because polluted freshwater is recalculated based on a critical dilution approach; (2) at the midpoint level, most methods are related to water scarcity index and correspond to the methodological choice of an indicator simplified in terms of the number of parameters (scarcity) and freshwater uses (freshwater consumption or freshwater withdrawal) considered. More comprehensive scarcity indices distinguish different freshwater types and functionalities. (3) At the endpoint level, several methods already exist which report results in units compatible with traditional human health and ecosystem quality damage and cover various cause–effect chains, e.g., the decrease of terrestrial biodiversity due to freshwater consumption. (4) Midpoint and endpoint indicators have various levels of spatial differentiation, i.e., generic factors with no differentiation at all, or country, watershed, and grid cell differentiation.ConclusionsExisting databases should be (1) completed with input and output freshwater flow differentiated according to water types based on its origin (surface water, groundwater, and precipitation water stored as soil moisture), (2) regionalized, and (3) if possible, characterized with a set of quality parameters. The assessment of impacts related to freshwater use is possible by assembling methods in a comprehensive methodology to characterize each use adequately.

Allocation in Life Cycle Inventory Analysis for Joint Production

Allocation in joint production is still one of the unresolved and often discussed methodological issues in Life Cycle Inventory Analysis. Using the many years of experience of man agement sciences, a new classification scheme is proposed. It is postulated that companies perform allocation in joint production in view of optimising the products’ performance (economic and/ or environmental), which helps them to maximise their profits. Therefrom it is derived that value judgements and negotiations are inevitable. The proposed classification scheme differentiates between the number of decision-makers involved, and the type of markets for joint products. Several decision-makers have to find fair allocation factors for their commonly operated joint production, whereas individual decision-makers may choose allocation factors considering the (economic and/ or environmental) competitiveness of their joint products. Applied on the case of a small-scale gas-fuelled combined heat and power plant, the methodology proposed shows a strong dependency on the disutility function, i.e., private costs, environmental damage costs or a combination of the two.

A special view on the nature of the allocation problem

One of the remaining important problems of life cycle inventory analysis is the allocation problem. A proper solution of this problem calls for a proper understanding of the nature of the problem itself. This paper argues that the established definition of the allocation problem as the fact that one unit process produces more than one function, is not appropriate. That definition points to an important reason of the occurrence of the problem, but the situation of internal (closed-loop) recycling already indicates that there may be product systems which contain multifunction processes, but which nevertheless need not exhibit an allocation problem. The paper proceeds by examining a number of simple hypothetical cases, and proposes a precise and operational definition of the allocation problem. This enables a systematic categorization of approaches for dealing with the allocation problem.

Global guidance on environmental life cycle impact assessment indicators: findings of the scoping phase

Olivier Jolliet & Rolf Frischknecht & Jane Bare & Anne-Marie Boulay & Cecile Bulle & Peter Fantke & Shabbir Gheewala & Michael Hauschild & Norihiro Itsubo & Manuele Margni & Thomas E. McKone & Llorenc Mila y Canals & Leo Postuma & Valentina Prado-Lopez & Brad Ridoutt & Guido Sonnemann & Ralph K. Rosenbaum & Tom Seager & Jaap Struijs & Rosalie van Zelm & Bruce Vigon & Annie Weisbrod & with contributions of the other workshop participants

Einstein's lessons for energy accounting in LCA

The role and meaning of accounting for energy, including feedstock energy, is reviewed in connection to Einstein’s special theory of relativity. It is argued that there is only one unambiguous interpretation of the term energy-content: The one that corresponds tome The implications for life cycle inventories is that all discussions concerning upper heating value, lower heating value, feedstock energy, etc. are pointless as long as the motivation for choosing one or the other is not specified in relation to the safeguard subjects defined for a particular analysis (LCA or energy analysis). The subjective aspects of energy accounting schemes, even though based on mere thermodynamics, are highlighted. In inventory analysis, it is recommended that energy carriers should be accounted separately and in mass terms.For illustrative purposes, energy statistics and energy assessment are discussed in view of the safeguard subjects underlying the accounting procedures. Based on a set of theses, one possible energy accounting scheme as an indicator of the “consumption of non-renewable energy resources” within the impact assessment of LCA is sketched. It is emphasised that energy accounting schemes do not reflect environmental impacts caused by the energy sources, and the characteristics of the indicator “consumption of non-renewable energy resources” introduced here are highlighted.

Global guidance on environmental life cycle impact assessment indicators: progress and case study

PurposeThe life cycle impact assessment (LCIA) guidance flagship project of the United Nations Environment Programme (UNEP)/Society of Environmental Toxicology and Chemistry (SETAC) Life Cycle Initiative aims at providing global guidance and building scientific consensus on environmental LCIA indicators. This paper presents the progress made since 2013, preliminary results obtained for each impact category and the description of a rice life cycle assessment (LCA) case study designed to test and compare LCIA indicators.MethodsThe effort has been focused in a first stage on impacts of global warming, fine particulate matter emissions, water use and land use, plus cross-cutting issues and LCA-based footprints. The paper reports the process and progress and specific results obtained in the different task forces (TFs). Additionally, a rice LCA case study common to all TF has been developed. Three distinctly different scenarios of producing and cooking rice have been defined and underlined with life cycle inventory data. These LCAs help testing impact category indicators which are being developed and/or selected in the harmonisation process. The rice LCA case study further helps to ensure the practicality of the finally recommended impact category indicators.Results and discussionThe global warming TF concludes that analysts should explore the sensitivity of LCA results to metrics other than GWP. The particulate matter TF attained initial guidance of how to include health effects from PM2.5 exposures consistently into LCIA. The biodiversity impacts of land use TF suggests to consider complementary metrics besides species richness for assessing biodiversity loss. The water use TF is evaluating two stress-based metrics, AWaRe and an alternative indicator by a stakeholder consultation. The cross-cutting issues TF agreed upon maintaining disability-adjusted life years (DALY) as endpoint unit for the safeguard subject “human health”. The footprint TF defined main attributes that should characterise all footprint indicators. “Rice cultivation” and “cooking” stages of the rice LCA case study contribute most to the environmental impacts assessed.ConclusionsThe results of the TF will be documented in white papers and some published in scientific journals. These white papers represent the input for the Pellston workshop™, taking place in Valencia, Spain, from 24 to 29 January 2016, where best practice, harmonised LCIA indicators and an update on the general LCIA framework will be discussed and agreed on. With the diversity in results and the multi-tier supply chains, the rice LCA case study is well suited to test candidate recommended indicators and to ensure their applicability in common LCA case studies.

Making sense of the minefield of footprint indicators.

Bradley Ridoutt,*,† Peter Fantke,‡ Stephan Pfister, Jane Bare, Anne-Marie Boulay, Francesco Cherubini, Rolf Frischknecht, Michael Hauschild,‡ Stefanie Hellweg, Andrew Henderson, Olivier Jolliet, Annie Levasseur, Manuele Margni, Thomas McKone, Ottar Michelsen, Llorenc Mila i Canals, Girija Page, Rana Pant, Marco Raugei, Serenella Sala, Erwan Saouter, Francesca Verones, and Thomas Wiedmann †Commonwealth Scientific and Industrial Research Organisation (CSIRO), Clayton, Victoria 3169, Australia ‡Technical University of Denmark (DTU), Department for Management Engineering, Division for Quantitative Sustainability Assessment, 2800 Kgs. Lyngby, Denmark ETH Zurich, Institute of Environmental Engineering, 8093 Zurich, Switzerland United States Environmental Protection Agency, Sustainable Technology Division, Systems Analysis Branch, National Risk Management Research Laboratory, Cincinnati, Ohio 45268, United States CIRAIG, Ecole Polytechnique de Montreal, Montreal, Canada Norwegian University of Science and Technology (NTNU), Industrial Ecology Programme, Department of Energy and Process Engineering, NO-7491 Trondheim, Norway treeze Ltd., Uster, Switzerland University of Texas Health Science Center, School of Public Health, Division of Epidemiology, Human Genetics and Environmental Sciences, Houston, Texas 77030, United States University of Michigan, School of Public Health, Environmental Health Sciences, Ann Arbor, Michigan 48109, United States University of California, Lawrence Berkeley National Laboratory and School of Public Health, Berkeley, California 94720, United States Norwegian University of Science and Technology (NTNU), Division for Finance and Property, NO-7491 Trondheim, Norway United Nations Environment Programme (UNEP), Division for Technology, Industry and Economics, 15 Rue de Milan, 75009 Paris, France University of Western Sydney, School of Science and Health, Penrith, NSW 2751, Australia European Commission, Joint Research Centre, Institute for Environment and Sustainability, Via Enrico Fermi 2749, Ispra, I-21027, Italy Oxford Brookes University, Department of Mechanical Engineering and Mathematical Sciences, Oxford OX33 1HX, United Kingdom UNSW Australia, Sustainability Assessment Program, School of Civil and Environmental Engineering, Sydney, NSW 2052, Australia

Evaluation of Long-Term Impacts in LCA

When looking at a product’s life cycle, emissions and resource uses, as well as the resulting impacts, usually occur at different points in time. For instance, construction materials are often ‘stored’ in buildings for many decades before they are recycled or disposed of. The goal of the LCA Discussion Forum 22 was to present and discuss arguments pro and contra a temporally differentiated weighting of impacts. The discussion forum started with three talks that illustrated the importance of temporal aspects in LCI and LCIA. The following two presentations discussed the economical principles of discounting, the adequacy of this concept within LCA, and the ethical questions involved. After one further short presentation, three groups were formed that discussed questions about temporally-differentiated weighting, and consequences for LCI as well as LCIA (damage assessment and final weighting). The discussion forum ended with the following conclusions: (a) long-term impacts should be considered in LCA, and (b) long-term emissions should be inventoried separately from short-term emissions. There was no consensus on whether short-term and long-term impacts should be weighted equally. Some prefer to weigh short-term emissions higher, because they are considered to be closer. Consistent and approved forecasts should be used when considering future changes in environmental conditions in LCI and LCIA.

Life cycle assessment in the building sector: analytical tools, environmental information and labels

The 57th life cycle assessment (LCA) forum was held on December 2, 2014 to discuss the European and Swiss situation with regard to the environmental assessment of buildings. This conference report presents the highlights of the LCA forum. Several methodological approaches exist to assess the environmental assessment of buildings. In Switzerland, all technical bulletins of the Swiss Society of Architects and Engineers (SIA) related to this topic and most labels and certification schemes rely on the KBOB recommendation 2009/1:2014, which in turn is based on the ecoinvent database. In Europe, the standards on environmental product declarations (EPD) of construction products and buildings and the guide on product environmental footprints published by the European Commission are applied. In Austria, France and Germany, environmental product declarations form an important part of certification schemes of buildings. The European construction product directive names the quantification of the environmental performance as one of the seven basic requirements on construction works. This basic requirement needs now to be embedded into the harmonised technical specifications (such as harmonised European Standards, hEN or European Technical Assessments (ETA)). The situation in Austria, France and Germany illustrates the diversity of European labels, certifications and information schemes even though they all refer to the European EPD standards. France for instance asks for requirements additional to the European Standards, and several labels using different life cycle assessment databases are in operation in Austria. On the other hand, the two main certification schemes in Germany use the same approach, indicators and database. Several initiatives are ongoing or being launched in Europe which try to further harmonise the environmental assessment of buildings and construction materials. The different presentations showed the variety of applications of life cycle-based environmental information in the planning process of buildings, ranging from conceptual decisions to suppliers’ choices, decisions on materialisation up to labelling and certification of built properties. It was concluded that unifying life cycle inventory methodology, environmental indicators and life cycle inventory background databases is most important in view of further harmonisation. At the same time, it was admitted that harmonisation in these areas is difficult if not out of reach.

Transparency in LCA-a heretical request?

However, publication practice changed dramatically within the last centuries. Today, publication is part of the research culture adopted by highly reputed universities. The Swiss Federal Institute of Technology Zurich (ETHZ), for instance, pays respect to the research culture based – among others – on unrestricted access to scientific knowledge, while respecting the legitimate interests of individuals or groups.