Showing papers in "International Journal of Life Cycle Assessment in 1999"
647 citations
378 citations
316 citations
TL;DR: In this paper, the authors defined marginal technologies as the technologies actually affected by the small changes in demand typically studied in prospective, comparative life cycle assessments using data on marginal technologies thus give the best reflection of the actual consequences of a decision.
Abstract: Marginal technologies are defined as the technologies actually affected by the small changes in demand typically studied in prospective, comparative life cycle assessments Using data on marginal technologies thus give the best reflection of the actual consequences of a decision Furthermore, data on marginal technologies are easier to collect, more precise, and more stable in time than data on average technologies A 5-step procedure is suggested to identify the marginal technologies The step-wise procedure first clarifies the situation in which the marginal should apply, and then identifies what specific technology is marginal in this situation The procedure is illustrated in two examples: European electricity production and pulp and paper production
302 citations
TL;DR: In this article, the production routes for five typical commercial sodium silicate products were traced back to the extraction of the relevant raw materials from the earth, in order to establish viable figures for the consumption of raw materials, water and energy and the emissions to air and water and solid waste generation.
Abstract: Soluble alkali silicate glasses, liquids and powders are an important class of primary synthetic chemicals and are produced in large quantities both in Europe and world-wide. They are utilised in a broad range of application fields, both industrial and domestic, including detergents, chemical feedstocks, paper manufacture, civil engineering and adhesives. In order to establish viable figures for the consumption of raw materials, water and energy and the emissions to air and water and solid waste generation, the production routes for five typical commercial sodium silicate products were traced back to the extraction of the relevant raw materials from the earth. Life Cycle Inventories for these products were compiled by EMPA St. Gallen / Switzerland on behalf of CEES, a Sector Group of CEFIC, using the data input based on the production of 1995 from 12 West European silicate producers covering about 93% of the total alkaline silicate production in Western Europe.
213 citations
181 citations
TL;DR: In this paper, the evaluation of product alternatives in Life Cycle Analysis (LCA) is a critical step on the basis of results as related to their impact category data, since decisions involving several environmental issues are hardly ever straightforward, since one alternative only seldom clearly dominates the others in all aspects.
Abstract: The evaluation of product alternatives in Life Cycle Analysis (LCA) is a critical step on the basis of results as related to their impact category data. Decisions involving several environmental issues are hardly ever straightforward, since one alternative only seldom clearly dominates the others in all aspects. More often, one alternative scores better on some environmental issues and worse on others. A combination of impact data and preferences is then required for evaluation. This can be done using evaluation methods based on fixed societal preferences. However, by applying different evaluation methods to the same data, different “best” alternatives may be chosen. This reduces the credibility of LCA results.
175 citations
TL;DR: In this paper, a case study of white bread has been carried out with the purpose of comparing different scales of production and their potential environmental effects, including home baking, a local bakery and two industrial bakeries with distribution areas of different sizes.
Abstract: A case study of white bread has been carried out with the purpose of comparing different scales of production and their potential environmental effects. The scales compared are: home baking, a local bakery and two industrial bakeries with distribution areas of different sizes. Data from the three bakeries and their suppliers have been collected. The systems investigated include agricultural production, milling, baking, packaging, transportation, consumption and waste management. Energy use and emissions have been quantified and the potential contributions to global warming, acidification, eutrophication and photo-oxidant formation have been assessed.
127 citations
Journal Article•
110 citations
TL;DR: This paper uses an industrial case study of a boron system producing five co-products to examine different allocation methods recommended by ISO 14041 and compare them with the allocation methods most commonly used by LCA practitioners and illustrates how the use of whole system modelling can help to identify the correct type of causality for allocation.
Abstract: This paper uses an industrial case study of a boron system producing five co-products to examine different allocation methods recommended by ISO 14041 and compare them with the allocation methods most commonly used by LCA practitioners In particular, allocation by physical causality is discussed The paper illustrates how the use of whole system modelling can help to identify the correct type of causality for allocation The case examined here concerns marginal changes of product-related parameters in the system, in this case represented by the output of boron co-products The analysis shows that in some cases it can he correct to allocate the burdens on the basis of a simple physical quantity, such as mass, as long as the allocation parameter is based on physical causation and is not chosen arbitrarily In whole system modelling, the correct causality is identified by the model itself, so that the possibility of allocation by an arbitrary parameter is avoided However, as for system disaggregation and expansion, allocation through mathematical modelling may only be possible if detailed data for the system are available
92 citations
TL;DR: In this paper, a decision support tool is developed to evaluate integrated municipal solid waste management strategies in the United States, including waste collection, transfer stations, recovery, compost, combustion, and landfill.
Abstract: Life-cycle assessment concepts and methods are currently being applied to evaluate integrated municipal solid waste management strategies throughout the world. The Research Triangle Institute and the U.S. Environmental Protection Agency are working to develop a computer-based decision support tool to evaluate integrated municipal solid waste management strategies in the United States. The waste management unit processes included in this tool are waste collection, transfer stations, recovery, compost, combustion, and landfill. Additional unit processes included are electrical energy production, transportation, and remanufacturing. The process models include methodologies for environmental and cost analysis. The environmental methodology calculates life cycle inventory type data for the different unit processes. The cost methodology calculates annualized construction and equipment capital costs and operating costs per ton processed at the facility. The resulting environmental and cost parameters are allocated to individual components of the waste stream by process specific allocation methodologies. All of this information is implemented into the decision support tool to provide a life-cycle management evaluation of integrated municipal solid waste management strategies.
TL;DR: In this article, the authors compared the performance of wind energy converters, solar water heating systems and photovoltaic systems for different types of locations and concluded that the latter two technologies tend to be better than the former.
Abstract: Calculation of Cumulative Energy Demand (CED) of various energy systems and the computation of their Energy Yield Ratio (EYR) suggests that one single renewable energy technology cannot be said to be the best. Due to the difference in availability of renewable energy sources, their suitability varies from place to place. Wind energy converters, solar water heating systems and photovoltaic systems have been analysed for different types of locations. Comparing the general bandwidth of performance of these technologies, however, the wind energy converters tend to be better, followed by solar water heating systems and photovoltaic systems.
TL;DR: In this paper, the authors derived indices for real damage based on the impact pathway methodology which involves the calculation of increased pollutant concentration in all affected regions due to an incremental emission (e.g. μg/m3 of particles, using models of atmospheric dispersion and chemistry), followed by the calculations of physical impacts (i.e. number of cases of asthma due to these particles, used a concentration-response function).
Abstract: In contrast to the various “potential impact” indices that have been proposed, we show that indices for real damage can be derived, based on the impact pathway methodology which involves the calculation of increased pollutant concentration in all affected regions due to an incremental emission (e.g. μg/m3 of particles, using models of atmospheric dispersion and chemistry), followed by the calculation of physical impacts (e.g. number of cases of asthma due to these particles, using a concentration-response function). The numbers are summed over all receptors of concern (population, crops, buildings,…). We show that in a uniform world (linear dose-response function, uniform receptor density and uniform atmospheric removal rate) the conservation of matter implies a very simple formula for the total damage. The generalization to secondary pollutants is straightforward. By detailed numerical evaluations, using real data for atmospheric dispersion and geographic receptor distribution, we have demonstrated that this simple formula is an excellent representation of typical damages. Results are shown for the principal air pollutants emitted by smoke stacks of industrial installations or by road transport.
TL;DR: The decision tool "Umweltbilanz von Altlastensanierungsverfahren" has been developed and found suitable for the quantification and evaluation of environmental impacts caused by remediation of contaminated sites as discussed by the authors.
Abstract: For the federal state of Baden-Wiirttemberg, Germany, the decision tool “Umweltbilanz von Altlastensanierungsverfahren” has been developed and found suitable for the quantification and evaluation of environmental impacts caused by remediation of contaminated sites. The developed tool complements the remediation toolbox of Baden-Wiirttemberg. The tool includes a streamlined life cycle assessment (LCA) and a synopsis of the LCA results with the results of a risk assessment of the contaminated site. The risk assessment tool is not explained here. The data base for the life cycle inventory includes several techniques used in remedial actions. The life cycle impact assessment utilises 14 impact categories. The method allows comparisons between remedial options for specific contaminated sites. A software tool has been developed to be available in 1999.
TL;DR: In this article, the authors explored the use of LCA as a tool for process environmental management, thereby moving the focus from product to process oriented analysis, where the emphasis is on improvement assessment in which the "hot spots" in the system are targeted for maximum environmental improvements.
Abstract: This paper explores the use of LCA as a tool for process environmental management, thereby moving the focus from product to process oriented analysis. The emphasis is on Improvement Assessment in which the “hot spots” in the system are targeted for maximum environmental improvements. In this context, it is useful to use multiobjective optimisation which renders Valuation unnecessary. The approach is illustrated by the case study of the system processing boron ores to make five different products. The results of Inventory Analysis and Impact Assessment are presented and discussed. In Improvement Assessment, a number of improvement options are identified and evaluated, using system optimisation. It is shown that the site environmental performance can be improved over current operation by an average of 20% over the whole life cycle. Thus the study demonstrates that the optimisation approach to environmental process management may assist in identifying optimal ways to operate a process or plant from “cradle to grave”. This may help the process industries not only to comply with legislation but also provide a framework for taking a more proactive approach to environmental management leading to more sustainable industrial operations and practices.
TL;DR: An international workshop was held to discuss Life Cycle Impact Assessment (LCIA) Sophistication as discussed by the authors, where a critical review of the associated factors, including the current limitations of available impact assessment methodologies and a comparison of the alternatives in the context of uncertainty, was presented.
Abstract: On November 29 – 30, 1998 in Brussels, an international workshop was held to discuss Life Cycle Impact Assessment (LCIA) Sophistication. Approximately 50 LCA experts attended the workshop from North America, Europe, and Asia. Prominent practitioners and researchers were invited to present a critical review of the associated factors, including the current limitations of available impact assessment methodologies and a comparison of the alternatives in the context of uncertainty. Each set of presentations, organised into three sessions, was followed by a discussion session to encourage international discourse with a view to improving the understanding of these crucial issues. The discussions were focused around small working groups of LCA practitioners and researchers, selected to include a balance of representatives from industry, government and academia. This workshop provided the first opportunity for International experts to address the issues related to LCIA Sophistication in an open format. Among the topics addressed were: 1) the inclusion or exclusion of backgrounds and thresholds in LCIA, 2) the necessity and practicality regarding the sophistication of the uncertainty analysis, 3) the implications of allowing impact categories to be assessed at “midpoint” vs. at “endpoint” level, 4) the difficulty of assessing and capturing the comprehensiveness of the environmental health impact category, 5) the implications of cultural/philosophical views, 6) the meaning of terms like science-based and environmental relevance in the coming ISO LCIA standard, 7) the dichotomy of striving for consistency while allowing the incorporation of state-of-the-art research, 8) the role of various types of uncertainty analysis, and 9) the role of supporting environmental analyses (e.g., risk assessments). Many of these topics addressed the need for increased sophistication in LCIA, but recognised the conflict this might have in terms of the comprehensiveness and holistic character of LCA, and LCIA in particular. The participants concluded that the exchange of ideas in this format was extremely valuable and would like to plan successive International workshops on related themes.
TL;DR: In this paper, the authors proposed a weighting factor that is a product of a reduction factor (Ni/Ti) and a relative significance factor (fi), where a politically determined critical impact (Ti/fi) is assumed to cause a critical damage defined as a level of damage acceptable to a society.
Abstract: A weighting factor proposed in this paper is a product of a reduction factor (Ni/Ti) and a relative significance factor (fi). A politically determined critical impact (Ti/fi) is assumed to cause a critical damage defined as a level of damage acceptable to a society. A graph showing the relationship between relative damage and normalized impact indicates that the weighting factor ((Ni/Ti) fi) is the slope of this graph. It shows further that the relative damage is the same as the weighted impact.
TL;DR: In this article, state of the art and research needs for the impact category eutrophication are discussed and the definition of the impact indicator needs further research, also the inclusion of other nutrients than those typically considered should also be investigated.
Abstract: State of the art and research needs for the impact category eutrophication are discussed. Eutrophication is a difficult impact category because it includes emissions to both air and water — both subject to different environmental mechanisms — as well as impacts occurring in different types of terrestrial and aquatic ecosystems. The possible fate processes are complex and include transportation between different ecosystems. In some recent approaches, transportation modelling of air emissions has been included. However, in general, the used characterisation methods do not integrate fate modelling, which is a limitation. The definition of the impact indicator needs further research, too. The inclusion of other nutrients than those typically considered should also be investigated.
TL;DR: In this article, the importance of use-related emissions from building materials in a life cycle perspective was assessed from both a regional and global perspective using case studies of linoleum, vinyl, and solid wood flooring.
Abstract: The results from two previously published case studies were used to assess the importance of use-related emissions from building materials in a life cycle perspective. The first study was an LCA study of linoleum, vinyl flooring, and solid wood flooring, while the second study examined the Volatile Organic Compounds (VOCs) emitted by these floorings. For linoleum and vinyl flooring, the emitted amounts for the use phase are of much the same magnitude as those emitted in the rest of the life cycle, but in the case of solid wood flooring the emissions of the use phase far exceed those of the remaining life cycle. The ranking of the selected floorings in the LCA study did not change when the impact of the use phase was also considered. This study recommends that LCAs should not neglect flooring-related emissions in the use phase when assessing regional and global environmental effects.
TL;DR: The status of Life Cycle Assessment (LCA) activities in the Nordic Region (period 1995-97) is presented, based on more than 350 reported studies from industrial companies and research institutes in Sweden, Denmark, Norway, and Finland as discussed by the authors.
Abstract: The status of Life Cycle Assessment (LCA) activities in the Nordic Region (period 1995-97) is presented, based on more than 350 reported studies from industrial companies and research institutes in Sweden, Denmark, Norway, and Finland. A large number of industrial sectors is represented, with car components, building materials, pulp and paper products, electronic components and packaging as the most important ones. All aspects of LCA methodology are used: 90% use impact assessment, 80% impact assessment and valuation step. In most studies, more than one valuation method is used for ranking environmental impacts.
TL;DR: This commentary discusses the two themes that underlie this change in terms and definitions of LCIA, including the arrival of a consensus that current LCIA indicators do not describe actual environmental impacts or effects.
Abstract: SETAC and ISO now describe the LCIA outcome as LCIA indicators. This contrasts with a SETAC definition of LCIA that is less than five years old. This commentary discusses the two themes that underlie this change in terms and definitions. The first theme is the arrival of a consensus that current LCIA indicators do not describe actual environmental impacts or effects. The second theme is the recognition that some of the ways used to generate indicators results in subjective scores while other ways involve highly simplified assumptions about complex environmental processes. The outcome of the new description is a new emphasis on LCIA transparency. Both the environmental relevance and the scientific basis of each indicator must now be described according to ISO. This increased transparency is essential for decision makers to understand the usefulness of LCIA indicators in making decisions and for audiences to understand what an LCA does or does not say about a product system.
TL;DR: In this article, an integrated approach for the assessment of cross-media aspects of techniques for the determination of BAT is outlined, which is grounded on the basic concept of Life Cycle Assessment, emphasising the need for decision support.
Abstract: The EC Directive concerning integrated pollution prevention and control (IPPC Directive 96/61/EC) obliges all Member States to make an integrated assessment of the impacts on the environment “as a whole”, as regards granting permission for and the operation of environmentally relevant industrial installations. The determination of “Best Available Techniques” BAT plays an essential role in the material transformation of the IPPC-Directive. An integrated approach for the assessment of cross-media aspects of techniques for the determination of BAT is outlined in this paper, which is grounded on the basic concept of Life Cycle Assessment (LCA), emphasising the need for decision support. The proposed assessment approach is applied to a case study sinter production in an integrated iron and steel works, which forms the base for several recommendations concerning further research.
TL;DR: In this article, the authors present a new method for life cycle impact assessment of human toxicity from air emissions that can take as well threshold evaluation and spatial source-differentiation into account.
Abstract: The absence of spatial and temporal information in the data from a typical Life Cycle Inventory puts constraints on the possibilities of subsequent Life Cycle Impact Assessment to predict actual impact. Usual methods for Life Cycle Impact Assessment (often referred to as “less is better” methods) make only limited use of spatial and temporal information, because they predict concentration increases rather than full concentrations. As a consequence it does not seem possible to evaluate whether a threshold value is surpassed. The resulting poor accordance between the predicted impact and the expected occurrence of actual impact is a major problem. This problem is particularly relevant for human toxicity assessment, since the probability of surpassing thresholds here traditionally is the main point of attention. A considerable group of practitioners suggests to follow an “only above threshold” principle by introduction of assessment tools from risk assessment and environmental impact assessment in LCA. Intensive debate is going on about possibilities and limitations of “less is better” and “only above threshold”. The debate is obscured by two underlying discussions (about no-effect-levels and about data-availability) that are partly, but not fully intertwined. Both principles tend to be given fixed positions in these discussions, and are therefore often put forward as fundamentally different and incompatible with each other. This article entwines the discussions, shows parallels between both principles, and uses these parallels to present a new method for Life Cycle Impact Assessment of human toxicity from air emissions that — with limited data requirement from Life Cycle Inventory — can take as well threshold evaluation and spatial source-differentiation into account.
TL;DR: The instances where physical causality can be represented by mass are examined and Whole system modelling and the marginal allocation approach are used to identify the correct type of causality for different operating states of the system and the corresponding changes in the environmenta burdens.
Abstract: ISO 14041 requires that allocation by physical causality must reflect the quantitative changes in product outputs or functions and will not necessarily be in proportion to simple physical measure such as mass This paper examines the instances where physical causality can be represented by mass However, it also goes further than ISO to demonstrate that the type of causality in the system is not necessarily always the same and can change depending on the way the system is operated Whole system modelling and the marginal allocation approach are used to identify the correct type of causality for different operating states of the system and the corresponding changes in the environmenta burdens This is generally not possible with the other allocation methods, also examined in this paper Both process- and product-related burdens are considered and the approach is illustrated by a reference to an existing system producing five boron co-products
TL;DR: Principal components analysis coupled with non-parametric bootstrapping is introduced with an example as a powerful tool to help visualise, analyse and decide on comparative or single non-deterministic LCI/LCIA results.
Abstract: Principal components analysis coupled with non-parametric bootstrapping is introduced with an example as a powerful tool to help visualise, analyse and decide on comparative or single non-deterministic LCI/LCIA results Decision support is provided by adding non-parametric bootstrapping (NPB) to the GA1A plane, which is a special case of principle comments analysis (PCA) built around the Promethee multicriteria decision aid model
TL;DR: There is a very close analogy between Life Cycle Assessment (LCA) and decision making tools such as the multicritcria approach and rules for the building of this family of environmental data are proposed.
Abstract: There is a very close analogy between Life Cycle Assessment (LCA) and decision making tools such as the multicritcria approach. LCA is a particular model of a multicriteria decision making tool which is applied to environmental data. The similarities between LCA and multicriteria decision making tools are highlighted. The strict precision of multicriteria decision making tools is used to improve classification. For this, six dimensions (or axes of significance) of environmental impacts can be distinguished. The aim is to build a coherent family of environmental data from these considerations. Rules for the building of this family are proposed.
TL;DR: In this article, the use of the new data results in a marked reduction of the total air emissions produced in the wheat production chain, especially for CO and HC, but also for NOx and SO2.
Abstract: The shortage of data for emissions from agricultural tractors contributes to LCA results on environmental load from modern crop production possibly having high error levels and high uncertainties. The first part of this work describes measurements and calculations made in order to obtain operation-specific agricultural emission data. Calculations are based on emission data measured on a standard 70 kW tractor of a widely available make. In the second part, results from an LCI on wheat production based on traditionally used emission data are calculated and compared with results obtained when using the emission data for specific working operations derived in part one. One conclusion of the study is that the emission values, when related to the energy in the used fuel, show very large variations between different driving operations. Another conclusion is that the use of the new data results in a marked reduction of the total air emissions produced in the wheat production chain, especially for CO and HC, but also for NOx and SO2.
TL;DR: In this paper, Dutch normalisation data are calculated for three different levels in order to give the LCA practitioner a more extended basis for preparing the interpretation process, the first level contains all impacts relating to activities that take place within the Dutch territory, the second level is based on the Dutch final consumption, which means that import and export are taken into account.
Abstract: In LCA, normalisation is applied to quantify the relative size of the impact scores. Several sets of normalisation data exist in the Netherlands, which all have a certain degree of unreliability. The purpose of this study is to actualise Dutch normalisation data and to make a framework for deriving these data. In this study normalisation data are calculated for three different levels in order to give the LCA practitioner a more extended basis for preparing the interpretation process. The first level of normalisation contains all impacts relating to activities that take place within the Dutch territory. The second level is based on the Dutch final consumption, which means that import and export are taken into account. The third level is an attempt to estimate impacts in Europe based on European data if possible, and otherwise based on extrapolation from the Dutch situation.
TL;DR: In this article, the authors examine the critique of discounting environmentalists have made in relation to property valuation, investment appraisal and the application of the principle in the income based net annual return model of land use time-horizons and the spatial configuration of building programmes.
Abstract: Previous editions of this Journal have drawn attention to the critical role valuation plays in life cycle analysis and environmental impact assessment (see for exampleVolkwkin andKlopffer |1|). In particular, the critical role of valuation has heen highlighed in a number of discussions on ‘valuation step’ within life cycle costing, ‘hedonic and contingency’ assessments of environmental impact and both the utility and welfare of ‘pathway’ analysis/assessment (Krkwitt, Mayerhofer, Trukenmuller andFriedrich, 1998;Powell, Pearce andCraighill, 1997;Volkwein, On in andKlopffer, 1996 |2-4|). Focusing on the utility of market valuation, this paper examines the critique of discounting environmentalists have made in relation to property valuation, investment appraisal and the application of the principle in the income based net annual return model of land use time-horizons and the spatial configuration of building programmes-a criticism implict in ‘valuation step’, ‘hedonic, contingency’ and ‘pathway’ analysis/assessments. It examines the argument put forward regarding the link between the selection of a discount rate, the valuation of property, appraisal of investment and inter-generational downloading of costs associated with the use of land, repair, maintenance and refurbishment of buildings: the downloading of costs, seen by some, to have an adverse impact and work against the introduction of experimental designs aimed at energy saving, clean air environments.