Bo Pedersen Weidema

• Ph.D.
• Professor (Full) at Aalborg University

This report provides the background for the two guidelines “The product, functional unit, and reference flows in LCA” (Weidema et al. 2003a) and “Geographical, technological and temporal delimitation in LCA” (Weidema 2003). It provides further documentation of the examples provided in these guidelines, as well as additional examples, further explan...

Recent developments in Life Cycle Impact Assessment (LCIA) provide a basis for reducing the uncertainty in monetarisation of environmental impacts. The LCIA method “Ecoindicator99” provides impact pathways ending in a physical score for each of the three safeguard subjects humans, ecosystems, and resources. We redefine these damage categories so th...

Purpose The practicality of social footprinting is currently hampered by an excessive data requirement, a lack of focus on materiality of the impacts, and a lack of understanding of the main impact pathways (cause-effect relationships) for social and economic impacts. We propose a “streamlined” method to overcome these barriers without loss of comp...

This report first presents a systematic overview of the life cycle of meat and dairy products and their environmental impacts, covering the full food chain. It goes on to provide a comprehensive analysis of the improvement options that allow reducing the environmental impacts throughout the life cycle. Finally, the report assesses the different opt...

Greenhouse-gas emission (GHG) metric values for methane in the sixth assessment report by the Intergovernmental Panel on Climate Change (IPCC) include the indirect effect associated to the oxidation of methane to CO2. An analysis of the figures provided by the IPCC reveals they assume that in average 75% of methane is ultimately oxidized to CO2, wh...

Sub-optimal dietary patterns make major contributions to the Global Burden of Disease and are among the most pressing issues affecting human health. Consequently, they are key to consider when assessing the human health and other environmental impacts of foods and diets within life cycle assessments. The UN Environment Life Cycle Initiative convene...

Purpose Ethylene and propylene production is currently included in life cycle assessment (LCA) databases using an attributional life cycle inventory (LCI) modelling approach. This approach entails modelling both products as co-products of the steam cracking process. In this article, we provide what, to the best of our knowledge, constitutes the fir...

Many life cycle assessments (LCA) studies on wooden buildings show potential to decarbonise the building industry, though often neglecting to consider the systemic changes of such a shift at the building stock scale. This study applies a consequential LCA to evaluate the transition from conventional construction to increased woodbased construction...

Input–output analyses are increasingly used to estimate consumption-based environmental footprints. The potential of estimates of social, economic, and ecosystem consequences of lifestyle interventions can be improved by detailing the complex way that final demand arises from patterns of household activities, i.e. from how households choose to use...

Purpose Following some years of practical application, some weaknesses have been identified in the original 2018 version of the ‘social footprint’ methodology, where wellbeing was seen as exclusively related to consumption activities and as inseparably linked to production through the budget constraint, implying that the value of wellbeing was limi...

The current practice for assessing the environmental life cycle impacts of a product system is limited to the activities that respond directly to a change in demand. The revenue resulting from this change in demand is then used to pay for primary factors, such as wages and taxes, while the redistribution of that money is left outside the system bou...

This article provides guidelines for conducting consequential life cycle assessment (LCA) studies. It presents the main features of two alternative approaches used in LCA-attributional and consequential-and describes how consequential LCA can be performed consistently and appropriately, with an example provided to guide practitioners. It is argued...

The use of Semantic Web and linked data increases the possibility of data accessibility, interpretability, and interoperability. It supports cross-domain data and knowledge sharing and avoids the creation of research data silos. Widely adopted in several research domains, the use of the Semantic Web has been relatively limited with respect to susta...

Modeling the use or the supply of recycled materials in a product-oriented Life Cycle Assessment (LCA) is challenging and a step in LCA that is typically associated with diverging practices and outcomes. In the ambition to harmonize LCA practices and increase the comparability of studies, the European Commission published the Product Environmental...

The current global interest in circular economy (CE) opens an opportunity to make society's consumption and production patterns more resource efficient and sustainable. However, such growing interest calls for precaution as well, as there is yet no harmonised method to assess whether a specific CE strategy contributes towards sustainable consumptio...

The current global interest in circular economy (CE) opens an opportunity to make society’s consumption and production patterns more resource efficient and sustainable. However, such growing interest calls for precaution as well, as there is yet no harmonised method to assess whether a specific CE strategy contributes towards sustainable consumptio...

Purpose This work provides an unambiguous conceptual framework for inclusion of nutrition in Life Cycle Assessments (LCAs) of food that enables the distinction between two different roles of nutrition, namely serving as the basis of food comparisons via the functional unit and as an impact pathway that links food ingestion with human health effects...

Life cycle interpretation is the fourth and last phase of life cycle assessment (LCA). Being a “pivot” phase linking all other phases and the conclusions and recommendations from an LCA study, it represents a challenging task for practitioners, who miss harmonized guidelines that are sufficiently complete, detailed, and practical to conduct its dif...

Purpose Considering the general agreement in the literature that environmental labelling should be based on consequential modelling, while all actually implemented environmental labelling schemes are based on attributional modelling, we investigate the arguments for this situation as provided in the literature, and whether a dual label, representin...

https://link.springer.com/article/10.1007/s11367-020-01736-6 free view only version: https://rdcu.be/b1dDH Purpose The safeguard subject of the Area of Protection “natural Resources,” particularly regarding mineral resources, has long been debated. Consequently, a variety of life cycle impact assessment methods based on different concepts are ava...

PurposeAssessing impacts of abiotic resource use has been a topic of persistent debate among life cycle impact assessment (LCIA) method developers and a source of confusion for life cycle assessment (LCA) practitioners considering the different interpretations of the safeguard subject for mineral resources and the resulting variety of LCIA methods...

A conceptually complete taxonomy is proposed at three levels of the impact pathway: Elementary flows, midpoint impacts, and endpoint impacts. The completeness is ensured conceptually by including unspecified residuals and by the use of fully quantifiable indicators that can be traced from source to sink, so that completeness can be verified by inpu...

Product footprint describes the environmental impacts of a product system. To identify such impact, Life Cycle Assessment (LCA) takes into account the entire lifespan and production chain, from material extraction to final disposal or recycling. This requires gathering data from a variety of heterogeneous sources, but current access to those is lim...

The assessment of ecosystem services (ES) is covered in a fragmented manner by environmental decision support tools that provide information about the potential environmental impacts of supply chains and their products, such as the well-known life cycle assessment (LCA) methodology. Within the flagship project of the Life Cycle Initiative (hosted b...

Developing a comprehensive ontology for product foot printing, to enable linking it with the semantic web.

Purpose This paper seeks to provide a detailed procedural description for performing a consistency check for LCA as required by the ISO 14044 standard. Methods Consistency is defined as freedom from logical contradictions. The requirements of ISO 14044 are reviewed, and detailed guidance is provided for these and other related consistency issues....

In our paper titled ‘Attributional or consequential life cycle assessment: a matter of social responsibility’ (Weidema et al., 2018), we conclude that “a consistent socially responsible decision-maker must always take responsibility for the activities in the consequential product life cycle and may additionally take responsibility for consequences...

This paper presents a market-price-based method to value sub-soil resources in environmental Cost-Benefit Analysis and Life Cycle Assessment. The market price incorporates the privileged information of the market agents, explicitly or implicitly anticipating future applications of the resource, future backstop technologies, recycling potentials, th...

PurposeWe investigate how the boundary between product systems and their environment has been delineated in life cycle assessment and question the usefulness and ontological relevance of a strict division between the two. Methods We consider flows, activities and impacts as general terms applicable to both product systems and their environment and...

_____ http://link.springer.com/article/10.1007/s11367-017-1297-8 _____ View only: http://rdcu.be/qlja _____ Purpose - In this paper, we summarize the discussion and present the findings of an expert group effort under the umbrella of the United Nations Environment Programme (UNEP)/Society of Environmental Toxicology and Chemistry (SETAC) Life Cycle...

The primary production of rare earth elements (REE) used in neodymium-iron-boron (Nd-Fe-B) magnets is associated with environmental impacts from both mining and processing. It has been suggested that recycling of scrap Nd-Fe-B magnets would reduce primary production of REE, and thus environmental impacts. However, existing studies on environmental...

Results of Life Cycle Assessment (LCA) are critically dependent on the system boundaries, notably the choice of attributional or consequential modelling. Published LCA studies rarely specify and justify their modelling choices. Since LCA studies are typically performed within the context of social responsibility and product life cycle management, t...

PurposeA systematic comparison is made of attributional and consequential results for the same products using the same unit process database, thus isolating the effect of the two system models. An analysis of this nature has only recently been made possible due to the ecoinvent database version 3 providing an access to both unallocated and unlinked...

PurposeBuilding on the rhetoric question “quo vadis?” (literally “Where are you going?”), this article critically investigates the state of the art of normalisation and weighting approaches within life cycle assessment. It aims at identifying purposes, current practises, pros and cons, as well as research gaps in normalisation and weighting. Based...

Three consistency problems are identified that arise when partitioning a product system with joint production according to an allocation key, such as revenue or mass of the joint products, namely: lacking consistency of rationales and procedures; lacking consistency of monetary, mass, and energy balances in the partitioned product systems; and lack...

Purpose Good background data are an important requirement in LCA. Practitioners generally make use of LCI databases for such data, and the ecoinvent database is the largest transparent unit-process LCI database worldwide. Since its first release in 2003, it has been continuously updated, and version 3 was published in 2013. The release of version 3...

Purpose This discussion article aims to highlight two problematic aspects in the International Reference Life Cycle Data System (ILCD) Handbook: its guidance to the choice between attributional and consequential modeling and to the choice between average and marginal data as input to the life cycle inventory (LCI) analysis. Methods We analyze the I...

Life Cycle Assessment (LCA) is the study of the environmental impact of products taking into account their entire life-span and production chain. This requires gathering data from a variety of heterogeneous sources into a Life Cycle Inventory (LCI). LCI preparation involves the integration of observations and engineering models with reference data...

Purpose Existing computational methods for life cycle costing (LCC) are few and appeared inconsistent with the very definition of LCC. This article improves the common matrix-based approach in life cycle assessment as applied to LCC, correcting previous errors. Methods Reusing a simple and hypothetical example, the authors derive the LCC from both...

Around 9% of global CO2 emissions originate from land use changes. Often, these emissions are not appropriately addressed in Life Cycle Assessment. The link between demand for crops in one region and impacts in other regions is referred to here as indirect land use change (iLUC) and includes deforestation, intensification and reduced consumption. E...

Monetary valuation is the practice of converting measures of social and biophysical impacts into monetary units and is used to determine the economic value of non-market goods, i.e. goods for which no market exists. It is applied in cost benefit analysis to enable the cross-comparison between different impacts and/or with other economic costs and b...

Assessing the effects of land use change (LUC) at the product level, as it is done in life cycle assessment (LCA) and carbon footprinting (CF), has been and still is subject to debate, especially when the focus is on so-called indirect land use change (iLUC). It is in this context that Prof. Matthias Finkbeiner recently published a report titled ‘I...

This document provides a point‐by‐point rebuttal, organised in the same order as the “key conclusions” in Prof. Finkbeiner’s study. We find most of the specific arguments or “key conclusions” of Prof. Finkbeiner to be misinformed, and do not find the main conclusion of the study to be supported by the evidence and arguments put forth. We provide ar...

The impact assessment methods Eco-Indicator 99 (H), Stepwise2006, and ReCiPe2008 (H) are compared with respect to the relative and absolute importance that they assign to the different mid-point impact categories. The comparison is done by a common monetary valuation of the three endpoints that are common to the three methods: human well-being, nat...

Purpose Data used in life cycle inventories are uncertain (Ciroth et al. Int J Life Cycle Assess 9(4):216–226, 2004). The ecoinvent LCI database considers uncertainty on exchange values. The default approach applied to quantify uncertainty in ecoinvent is a semi-quantitative approach based on the use of a pedigree matrix; it considers two types of...

Purpose Ecoinvent applies a method for estimation of default standard deviations for flow data from characteristics of these flows and the respective processes that are turned into uncertainty factors in a pedigree matrix, starting from qualitative assessments. The uncertainty factors are aggregated to the standard deviation. This approach allows c...

Can be downloaded at https://lca-net.com/publications/show/overview-methodology-data-quality-guideline-ecoinvent-database-version-3/

Purpose To assess the diverse environmental impacts of land use, a standardization of quantifying land use elementary flows is needed in life cycle assessment (LCA). The purpose of this paper is to propose how to standardize the land use classification and how to regionalize land use elementary flows. Materials and methods In life cycle inventorie...

Purpose Biological sequestration can increase the carbon stocks of non-atmospheric reservoirs (e.g. land and land-based products). Since this contained carbon is sequestered from, and retained outside, the atmosphere for a period of time, the concentration of CO 2 in the atmosphere is temporar-ily reduced and some radiative forcing is avoided. Carb...

II The Agricultural Economics Research Institute (LEI) is active in a wide array of research which can be classified into various domains. This report reflects research within the following domain: þ Business development and external factors Emission and environmental issues Competitive position and Dutch agribusiness; Trade and industry Economy of...

In the new version 3 of the ecoinvent LCI database, the user can choose between different system models that reflect different LCI modelling algorithms applied to the same underlying unit process data. The system models reflect different consequential and attributional models, i.e. linking of inputs to either average or unconstrained suppliers, and...

This chapter presents a view on the current international research in workplace learning. The chapter is introduced by quoting the requirements on employee participation and training in the European regulation on environmental management and audit systems, and outlining the value of employee participation and training in the development, implementa...

Allocation in life cycle inventory (LCI) analysis is one of the long-standing methodological issues in life cycle assessment (LCA). Discussion on allocation among LCA researchers has taken place almost in complete isolation from the series of closely related discussions from the 1960s in the field of input−output economics, regarding the supply and...

Embedding the ecoinvent process database into a hybrid (monetary and physical) supply-use framework, based on data on prices, material content and lifetime of products, the material inputs to the economy, as provided in resource statistics, can be traced through the economy until their eventual release as emissions. This additional feature will all...

Global warming potential (GWP) is an important impact category in life-cycle-assessment modelling of waste management systems. However, accounting of biogenic CO(2) emissions and sequestered biogenic carbon in landfills and in soils, amended with compost, is carried out in different ways in reported studies. A simplified model of carbon flows is pr...

As a supplement to the site, substance and media specific environmental policies, Denmark has had, since 1998, a product-oriented environmental policy (at the European level known as “Integrated Product Policy”). The policy has been organized as prioritized activities in selected sectors and/or product areas. This prioritization was informed by the...

Behind the life cycle of a product, from the cradle to the grave, there is a story to tell. Not only about its potential impact on the environment, but as well in terms of social and socio-economic impacts - or potential impacts - of its production and consumption on the workers, the local communities, the consumers, the society and all value chai...

Background, Aims and ScopeThe consequential approach to system delimitation in LCA requires that consideration of the technologies and suppliers included are ‘marginal’, i.e. that they are actually affected by a change in demand. Furthermore, coproduct allocation must be avoided by system expansion. Vegetable oils constitute a significant product g...

Goal, Scope and Background Traditionally, comparative life cycle assessments (LCA) have not considered rebound effects, for instance in case of significant price differences among the compared products. No justifications have been made for this delimitation in scope. This article shows that price differences and the consequent effects of marginal c...

To focus Danish product-oriented environmental policy, a study applying extended input-output analysis has been performed, identifying the most important product groups from an environmental perspective. The environmental impacts are analyzed from three different perspectives—the supply perspective, the consumption perspective, and the process pers...

1 Abstract The feasibility study was prepared in a multi-stage discussion process within the context of the Task Force "Integration of social aspects into LCA" of the UNEP-SETAC Life Cycle Initiative. The methodology of environmental or biophysical LCA was taken and checked whether and how social aspects can be integrated or supplemented to conduct...

- DOI: http://dx.doi.org/10.1065/lca2006.04.016 Goal, Scope and Background Although both cost-benefit analysis (CBA) and life cycle assessment (LCA) have developed from engineering practice, and have the same objective of a holistic ex-ante assessment of human activities, the techniques have until recently developed in relative isolation. This has...

This is the main report of the project “Prioritisation within the integrated product policy” commissioned by the Danish Environmental Protection Agency in the years 2003-4. The main objectives of the project was to: • Establish a detailed and well-documented method for prioritising product areas and product groups where Danish measures will provi...

Background The quantification of resource depletion in Life Cycle Assessment has been the topic of much debate; to date no definitive approach for quantifying effects in this impact category has been developed. In this paper we argue that the main reason for this extensive debate is because all methods for quantifying resource depletion impacts hav...

Background, Aims and Scope Life Cycle Impact Assessment (LCIA) methods can be grouped into two families: classical methods determining impact category indicators at an intermediate position of the impact pathways (e.g. ozone depletion potentials) and damage-oriented methods aiming at more easily interpretable results in the form of damage indicator...

Sustainable development requires methods and tools to measure and compare the environmental impacts of human activities for the provision of goods and services (both of which are summarized under the term "products"). Environmental impacts include those from emissions into the environment and through the consumption of resources, as well as other i...

Goal, Scope and BackgroundA consequential life cycle assessment (LCA) is designed to generate information on the consequences of decisions. This paper includes a comprehensive presentation of the consequential approach to system boundaries, allocation and data selection. It is based on a text produced within the SETAC-Europe working group on scenar...

The subject of this guideline is some of the first elements of a life cycle study, typically following immediately after the definition of the goal of the study, namely: • the determination of relevant product functions and product alternatives (i.e the object of the study), • the definition of the functional unit, and the determination of the refe...

ANNOTATION

This report has been prepared with the aim of demonstrating how a data collection strategy can be based on understanding the causes of variation in the technological, geographical and temporal aspects of the processes included in a life cycle assessment. The objective of a data collection strategy is to prioritise the data collection so that the ne...

It all started with a new version of the environmental scheme drafted by Helias Udo de Haes and Erwin Lindeijer in November 2000 for use in the final phase of SETAC Europe's 2nd Working group on (life cycle) Impact Assessment (WIA-2). This group convened the day after the 8th LCA Case Studies Symposium in Brussels, Dezember 1, 2000. There was not e...