Integration of Functional and Environmental Performance Design Decisions: A Mechanical Component Case Study

Product design-for-environment (DfE) has traditionally relied on life-cycle assessment (LCA) as a primary means of assessing environmental performance. To date, LCA has focused on static inventory and impacts of material streams during the stages of resource extraction, component manufacture, product use, and end of life at a high level of aggregation. Improvement analysis, though theoretically an important stage of LCA, is practically very challenging to implement using LCA alone. One reason for this is that the focus on detailed characterization of material streams does not facilitate a development of an understanding of the mechanistic relationship between design intent and material, manufacturing, and use-phase potential impacts. As the product development community transitions from sequential design to more streamlined concurrent design, interactive design tools are needed as a supplement to assessment tools in order to facilitate tradeoffs among environmental and other factors. This article presents an environmental analysis approach based on detailed process modeling which evaluates components from a functional design point of view. From a manufacturer's perspective, local potential effects in aggregate are often as important as global potential impacts. Furthermore, impacts often relate to explicit trade-offs between different life-cycle stages, such as production and use. In this article, the influence of functional design and manufacturing specifications (surface tolerance and finish) on localized potential impacts is illustrated through two different mechanical component (steel roller bearing and rotating shaft) case studies. Detailed analytical tools are key in enabling optimization and trade-offs by designers and process planners. The functional modeling approach is an important complement to LCA in providing a well-defined view of environmental performance.     

Applying Life Cycle Tools and Process Engineering to Determine the Most Adequate Treatment Process Conditions. A Tool in Environmental Policy (12 pp)

Background The analysis of a wastewater treatment technology, under a expanded boundaries system which includes both the technology and the inputs required for its operation, quantifies the overall environmental impact that may result from the treatment of a wastewater stream. This is particularly useful for environmental policy makers being that a expanded boundaries system tends to provide a holistic view. The former view can be highly enriched with the use of process engineering tools, such as mathematical process modelling, process design, performance assessment and cost optimised models. Main Features The traditional approach used to assess waste treatment technologies is contrasted with a life cycle analysis (LCA) approach. The optimal design of a granular activated carbon adsorption (GAC) process is used as a model system to demonstrate the advantages of LCA approaches over traditional approaches. Further sections of the paper describe a mathematical framework for the assessment of technologies, design considerations applied in the cost optimised carbon adsorption model, the use of LCA techniques to perform an inventory of all emissions associated to the process system and, some of its environmental impacts. Results Economic and environmental considerations regarding the optimum process design are introduced as a basis for decision towards the selection and operating conditions of wastewater treatment technologies. Moreover, the use of LCA has revealed that the environmental burden associated with the wastewater treatment may produce a higher environmental impact than one that can be caused by untreated discharges. Conclusion The paper highlights the string advantages that environmental policy makers may have by combining LCA and process engineering tools. Furthermore, this approach can be incorporated into other existing treatment processes or for process designers.     

A Practical Method for Quantifying Eco-efficiency Using Eco-design Support Tools

Eco-efficiency at the product level is defined as product value per unit of environmental impact. In this paper we present a method for quantifying the eco-efficiency using quality function deployment (QFD) and life-cycle impact assessment (LCIA). These well-known tools are widely used in the manufacturing industry.
QFD, which is one of the methods used in product development based on consumer preferences, is introduced to calculate the product value. An index of the product value is calculated as the weighted average of improvement rates of quality characteristics. The importance of customer requirements, derived from the QFD matrix, is applied.
Environmental impacts throughout a product life cycle are calculated based on an LCIA method widely used in Japan. By applying the LCIA method of endpoint type, the endpoint damage caused by various life-cycle inventories is calculated. Willingness to pay is applied to integrate it into a single index.
Eco-design support tools, namely, the life-cycle planning (LCP) tool and the life-cycle assessment (LCA) tool, have already been developed. Using these tools, data required for calculation of the eco-efficiency of products can be collected. The product value is calculated based on QFD data stored in the LCP tool and the environmental impact is calculated using the LCA tool.
Case studies of eco-efficiency are adopted and the adequacy of this method is clarified. Several advantages of this method are characterized.     

Product Environmental Life-Cycle Assessment Using Input-Output Techniques

Life-cycle assessment (LCA) facilitates a systems view in environmental evaluation of products, materials, and processes. Life-cycle assessment attempts to quantify environmental burdens over the entire life-cycle of a product from raw material extraction, manufacturing, and use to ultimate disposal. However, current methods for LCA suffer from problems of subjective boundary definition, inflexibility, high cost, data confidentiality, and aggregation.
This paper proposes alternative models to conduct quick, cost effective, and yet comprehensive life-cycle assessments. The core of the analytical model consists of the 498 sector economic input-output tables for the U.S. economy augmented with various sector-level environmental impact vectors. The environmental impacts covered include global warming, acidification, energy use, non-renewable ores consumption, eutrophication, conventional pollutant emissions and toxic releases to the environment. Alternative models are proposed for environmental assessment of individual products, processes, and life-cycle stages by selective disaggregation of aggregate input-output data or by creation of hypothetical new commodity sectors. To demonstrate the method, a case study comparing the life-cycle environmental performance of steel and plastic automobile fuel tank systems is presented.     

Environmentally Conscious Product Design: A Collaborative Internet-based Modeling Approach

This paper proposes a computer-based method for providing product designers with real-time environmental impact assessment. In this concurrent modeling approach, environmental experts build life-cycle models, define their interfaces, and publish them as distributed objects on the Internet. Traditional designers integrating these objects into their design models have access to the impact assessment methods provided by the environmental expert. In this paradigm, the focus shifts from providing techniques that let non-expert designers perform life-cycle impact assessments to tools that facilitate timely communication and information transfer between designers and appropriate environmental experts. Establishing real-time communication between the product design models and the environmental life-cycle models is the primary focus of this paper. Methods for establishing and maintaining the interaction between life-cycle and product design models are described. A beverage container design example illustrates how this collaborative approach can use environmental and traditional design goals to determine effective tradeoffs between design alternatives.     

A Decision Support Framework for Sustainable Waste Management

This article describes a decision support framework for the evaluation of scenarios for the integrated management of municipal solid waste within a local government area (LGA).
The work is initially focused on local government (i.e., municipal councils) in the state of Queensland, Australia; however, it is broadly applicable to LGAs anywhere. The goal is to achieve sustainable waste management practices by balancing global and regional environmental impacts, social impacts at the local community level, and economic impacts. The framework integrates life-cycle assessment (LCA) with other environmental, social, and economic tools. For this study, social and economic impacts are assumed to be similar across developed countries of the world. LCA was streamlined at both the life-cycle inventory and life-cycle impact assessment stages.
For this process, spatial resolution is introduced into the LCA process to account for impacts occurring at the local and regional levels. This has been done by considering social impacts on the local community and by use of a regional procedure for LCA data for emissions to the environment that may have impacts at the regional level.
The integration follows the structured approach of the pressure-state-response (PSR) model suggested by the Organisation for Economic Cooperation and Development (OECD). This PSR model has been extended to encompass nonenvironmental issues and to guide the process of applying multiple tools.
The framework primarily focuses on decision analysis and interpretation processes. Multiattribute utility theory (MAUT) is used to assist with the integration of qualitative and quantitative information. MAUT provides a well-structured approach to information assessment and facilitates objective, transparent decisions. A commercially available decision analysis software package based on MAUT has been used as the platform for the framework developed in this study.     

Weighting in Practice:Implications for the Use of Life-Cycle Assessment in Decision Making

This article investigates how environmental trade-offs are handled in life-cycle assessment (LCA) studies in some Nordic companies. Through interviews, the use and understanding of weighting methods in decision making was studied. The analysis shows that the decision makers require methods with which to aggregate and help interpret the complex information from life-cycle inventories. They agreed that it was not their own values that should be reflected in such methods, but they were found to have different opinions concerning the value basis that should be used. The analysis also investigates the difficulties arising from using such methods. The decision makers seemed to give a broader meaning to the term weighting, and were more concerned with the comparison between environmental and other aspects than the weighting of different environmental impacts. A conclusion is that decision makers need to be more involved in modeling and interpretation. The role of the analyst should be to interpret the information needs of the decision maker, and help him or her make methodological choices that are consistent with these needs and relevant from his or her point of view. To achieve this, it is important that decision makers do not view LCA as a highly standardized calculation tool, but as a flexible process of collecting, organizing, and interpreting environmental information. Such an approach to LCA increases the chances that the results will be regarded as relevant and useful.     

Life Cycle Approach in the Procurement Process: The Case of Defence Materiel (9 pp)

Goal, Scope and Background Procurement in public and non-public organisations has the potential to influence product development towards more environmentally friendly products. This article focuses on public procurement with procurement in Swedish defence as a special case. In 2003, public procurement in Sweden was 28% of the GDP. In the Swedish defence sector the amount was 2% of the GDP. The total emissions from the sector were of the same order of magnitude as from waste treatment (2% of Sweden's emissions). According to an appropriation letter from the Ministry of Defence in 1998, the Swedish Armed Forces (SAF) and the Swedish Defence Materiel Administration (FMV) are required to take environmental issues into consideration during the entire process of acquiring defence materiel. Environmental aspects are considered today, but without a life-cycle perspective. - The aims of this article are to recommend suitable tools for taking environmental concerns into account, considering a product's life-cycle, in the procurement process for defence materiel in Sweden; to make suggestions for how these tools could be used in the acquisition process; and to evaluate these suggestions through interviews with actors in the acquisition process. The procurement process does not include aspects specific to Swedish defence, and it is therefore likely to be comparable to processes in other countries. Methods The method involved a study of current literature and interviews with various actors in the acquisition process. The life cycle methods considered were quantitative Life Cycle Assessments, a simplified LCA-method called the MECO method and Life Cycle Costing (LCC). Results and Discussion Methodology recommendations for quantitative LCA and simplified LCA are presented in the article, as well as suggestions on how to integrate LCA methods in the acquisition process. We identified four areas for use for LCA in the acquisition process: to learn about environmental aspects of the product; to fulfil requirements from customers; to set environmental requirements and to choose between alternatives. Therefore, tools such as LCAs are useful in several steps in the acquisition process. Conclusion From the interviews, it became clear that the actors in the acquisition process think that environmental aspects should be included early in the process. The actors are interested in using LCA methods, but there is a need for an initiative from one or several of them if the method is to be used regularly in the process. Environmental and acquisition issues are handled with very little interaction in the controlling and ordering organisation. An integration of environmental and acquisition parts in these organisations is probably needed in order to integrate environmental aspects in general and life-cycle thinking in particular. Other difficulties identified are costs and time constraints. Recommendation and Perspective In order to include the most significant aspects when procuring materiel, it is important to consider the whole life-cycle of the products. Our major recommendation is that the defence sector should work systematically through different product groups. For each product group, quantitative, traditional LCAs or simplified LCAs (in this case modified MECOs) should be performed for reference products within each product group. The results should be an identification of critical aspects in the life-cycles of the products. The studies will also form a database that can be used when making new LCAs. This knowledge should then be used when writing specifications of what to procure and setting criteria for procurement. The reports should be publicly available to allow reviews and discussions of results. To make the work more cost-effective, international co-operation should be sought. In addition, LCAs can also be performed as an integrated part of the acquisition process in specific cases.     

Recent Advances in Design for Environment at Motorola

Motorola is a large electronics company that uses design for environment (DfE) t o address our customers' environmental needs. In working to integrate environmental considerations into product design, Motorola has encountered new challenges in product design, and as a result has had to develop new frameworks and employ new analytical tools. This article describes those challenges and Motorola's efforts to date. The examination of how products are designed in Motorola led to the realization that there are distinct phases in design: concept development, detail design, and prototype manufacture. In the earlier phases where the greatest flexibility for product reconfiguration exists, there is the least amount of detailed information available for use in making environmental assessments. In an effort to match the data availability to the environmental assessment needs, Motorola developed a tiered approach to DE using a matrix-based abridged life-cycle assessment (LCA) in the concept development stage, a scoring system based in part on multiattribute value theory in the detail design stage, and potentially full-scale life-cycle assessment in the prototype manufacturing stage.     

End-of-life of a polypropylene bumper skin

The aim of this article is to show how, at PSA peugeot-citroën, Life Cycle Assessment (LCA) is used as a tool to evaluate the environmental burdens associated with a product, a process or an activity by identifying and quantifying energy, material used and wastes released to the environment. In this paper, the LCA methodology is applied to a practical case study: the comparison of various end-of-life scenarios (recycling versus incineration with or without energy recovery with landfill as a reference) for a polypropylene (PP) bumper skin. All the LCA steps (goal, inventory, impacts assessment, interpretation) are developed in this study. It is shown that in the particular case of PP, incineration with energy recovery is on an environmental point of view between 30 and 60% recycling. However, due to some uncertainties on data quality, the absolute values of the inputs/outputs for the inventory step may not be sufficient to allow strong decision making and the use of the factorial experiments (Taguchi) is then proposed to select the dominant parameters of the study. Strong environmental conclusions can then be drawn from the study.     

Using GaBi 3 to perform life cycle assessment and life cycle engineering

The growing availability of software tools has increased the speed of generating LCA studies. Databases and visual tools for constructing material balance modules greatly facilitate the process of analyzing the environmental aspects of product systems over their life cycle. A robust software tool, containing a large LCI dataset and functions for performing LCIA and sensitivity analysis will allow companies and LCA practitioners to conduct systems analyses efficiently and reliably. This paper discusses how the GaBi 3 software tool can be used to perform LCA and Life Cycle Engineering (LCE), a methodology that combines life cycle economic, environmental, and technology assessment. The paper highlights important attributes of LCA software tools, including high quality, well-documented data, transparency in modeling, and data analysis functionality. An example of a regional power grid mix model is used to illustrate the versatility of GaBi 3.     

Assessing potential desertification environmental impact in life cycle assessment

Background, aim and scope  

Life cycle assessment (LCA) enables the objective assessment of global environmental burdens associated with the life cycle of a product or a production system. One of the main weaknesses of LCA is that, as yet, there is no scientific agreement on the assessment methods for land-use related impacts, which results in either the exclusion or the lack of assessment of local environmental impacts related to land use. The inclusion of the desertification impact in LCA studies of any human activity can be important in high-desertification risk regions.     

A Process Chaining Approach toward Product Design for Environment

This article presents an approach toward product design for environment (DfE) at the level that integrates environmental hazard analysis with models of transformation processes. As a complementary analysis tool to life-cycle assessment (LCA), this method would support detailed design decisions through modeling of a "process chain" for a subset of the product's life cycle. The building blocks for this approach are a set of unit process models that can convert process and design parameters into estimates for energy utilization, production scrap, and ancillary waste flows. These values for quantity of environmental releases can be integrated using a multicriiteria environmental hazard evaluation methodology that can estimate the "qualrty" of environmental releases. Finally, the waste information can be used to support a design model that can link design parameters to material, process, and operational parameter selection. A case study illustrating printed circuit board (PCB) assembly is presented to show process chain implementation in manufacturing applications.     

Using LCA to examine greenhouse gas abatement policy

The site-generic approach currently adopted by the Life Cycle Assessment (LCA) methodology introduces uncertainties into the impact assessment phase of an LCA study. These uncertainties are greatest for localised and short-lived problems but are less significant for long lasting, cumulative environmental effects. Indeed, the reliability of LCA results is high for problems that manifest at a global scale. Nevertheless, even though these results are considered accurate, it is still often unclear as to their relevance in terms of policy development and decision-making. Therefore, this paper demonstrates how LCA can be used to determine the efficacy of policies aimed at reducing a product system’s contribution to global environmental problems. We accomplish this aim by presenting a case study that evaluates the greenhouse gas contributions of each stage in the life cycle of containerboard packaging and the potential impact on emissions of various policy options available to decision makers. Our analysis showed that in general the most useful strategy was to recycle the used packaging. However, our analysis also indicated that when measures are taken to eliminate sources of methane emissions and encourage the use of plantation timber then recycling is no longer beneficial from a greenhouse perspective. This is because the process energy required in the form of gas and electricity is substantially greater for containerboard manufactured from recycled material than it is for virgin fibre.     

Institutionalization of Life-Cycle Thinking in the Everyday Discourse of Market Actors

The widespread popularity of life-cycle assessment (LCA) is difficult to understand from the point of view of instrumental decision making by economic agents. Ehrenfeld has argued, in a 1997 issue of this journal, that it is the world-shaping potential of LCA that is more important than its use as a decision-making tool. The present study attempts to explore the institutionalization of this "LCA world view" among ordinary market actors. This is important because environmental policy relies increasingly on market-based initiatives. Cognitive and normative assumptions in authoritative LCA documents are examined as empirical data and compared with data from focus group interviews concerning products and the environment with "ordinary" manufacturers, retailers, and consumers in Finland. These assumptions are (1) the "cradle-to-grave" approach, (2) the view that all products have an environmental impact and can be improved, (3) the relativity of environmental merit, and (4) the way responsibility for environmental burdens is attributed. Relevant affinities, but also differences, are identified. It is argued that life-cycle thinking is not primarily instrumental, but rather is gaining a degree of intrinsic value. The study attempts to establish a broader institutional context in which the popularity of LCA can be understood. From the point of view of this broader context, some future challenges for the development of LCA and life-cycle thinking are suggested.     

The relative mass-energy-economic (RMEE) method for system boundary selection Part 1: A means to systematically and quantitatively select LCA boundaries

Life-cycle assessment (LCA) is being used more and more as a decision making tool to compare alternative systems of providing a given product or service. Each system is theoretically made up of a near infinite number of elements or unit processes to produce the product or service. In practice, time and resources to complete an LCA are limited, hence the need to draw practical boundaries on the systems being analyzed. However, how does the LCA practitioner draw fair boundaries on two or more different systems being compared? In other words, how does one decide which unit processes to include in each system? A consistent quantitative method of selecting boundaries is essential for comparative LCA studies. This paper first outlines the requirements for a system boundary selection methodology and then demonstrates the shortfalls of existing methods. The primary objective is to present the Relative Mass-Energy-Economic (RMEE) method for system boundary selection. This concise, repeatable and quantitative method for selecting system boundaries for LCA is demonstrated on a life-cycle system for ethanol fuel. Unlike many other methods of selecting system boundaries, the RMEE method is practical to use and quantitatively ensures different systems have similar system boundaries to ensure a fair comparison between options. The RMEE method has been designed specifically for LCA studies of energy systems     

Predicted environmental impact and expected occurrence of

The necessity of the impact assessment phase in life-cycle assessment (LCA) is presently debated. The crux of the debate lies in the poor accordance in some I.CA studies between the predicted environmental impact and the expected occurrence of actual environmental impact. That is in particular the case for impacts of a continental, regional and local character. We consider an impact assessment as being an indispensable phase of LCA, and see options for solving the identified problem. This article takes a closer look into the nature of the assessed impact in LCA in order to provide the basis for enhancement of life-cycle impact assessment. LCA is one of the analytical tools to support environmental policy focused on the control of present environmental problems. Nowadays, environmental problems are caused by concentration levels that result from the emissions of many sources together, rather than from single sources alone. The contribution from a single source is usually small or even marginal in comparison with the total contribution from all sources together. The multiple source character of the related impact categories provides the justification for the linear nature of the assessed impact in LCA. An article in the next issue of this journal will build further on this article, and will discuss the inclusion of temporal and spatial aspects (by a site-dependent approach) in order to enhance the accordance between the predicted environmental impact and the expected occurrence of actual environmental impact.     

Similarities,Differences and Synergisms Between HERA and LCA—An Analysis at Three Levels

Linkages between Human and Environmental Risk Assessment (HERA) and Life-Cycle Assessment (LCA) can be analyzed at three levels: the basic equations to describe environmental behavior and dose-response relationships of chemicals; the overall model structure of these tools; and the applications of the tools. At level 1 few differences exist: both tools use essentially the same fate and effect models, including their coefficients and data. At level 2 distinctive differences emerge: regional or life-cycle perspective, emission pulses or fluxes, scope of chemicals and types of impacts, use of characterization factors, spatial and temporal detail, aggregation of effects, and the functional unit as basis of the assessment. Although the two tools typically differ in all these aspects, only the functional unit issue renders the tools fundamentally different, expressing itself also in some main characteristics of the modeling structure. This impedes full integration, which is underpinned in mathematical terms. At level 3 the aims of the tools are complementary: quantified risk estimates of chemicals for HERA versus quantified product assessment for LCA. Here, beneficial synergism is possible between the two tools, as illustrated by some cases. These also illustrate that where full integration is suggested, in practice this is not achieved, thus in fact supporting the conclusions.     

Evaluating Human and Ecological Impacts of a Product Life Cycle: The Complementary Roles of Life-Cycle Assessment and Risk Assessment

Life-cycle assessment (LCA) is a tool for evaluating various health and environmental impacts throughout a product's life. When used as a screening tool, LCA can potentially identify the processes and materials most likely to pose a threat to human health and the environment, and to determine where a risk assessment is warranted. The European Union has issued a ban on lead-based solder from use in electronic equipment beginning in July 2006. In response, the Lead-Free Solder Partnership, involving the U.S. Environmental Protection Agency, several electronics manufacturers, and the University of Tennessee afforded a vehicle for conducting a thorough LCA of leaded and lead-free solders used in the electronics industry. Sixteen impact categories were evaluated in the LCA, including human toxicity.

A primary conclusion of the assessment for human and aquatic toxicity, across the entire life cycle of tin-lead solder, was the potential for impacts derived from the landfilling of lead. These results, based on broad assumptions about exposure, suggest that a more detailed risk assessment of the landfilling process would assist in better understanding the potential for health and environmental risks. We believe LCA data can be used to identify the need for focused risk assessments, allowing the two tools to effectively complement one another. Use of both methods could assist in understanding the effectiveness of the European ban on lead solder and its potential to improve public health.     

Determination of environmental impacts of antimicrobial usage for US Northern Great Plains swine-production facilities: a life-cycle assessment approach

Purpose  

This study used life-cycle assessment (LCA) methodology to examine the environmental effects associated with sub-therapeutic tylosin and chlortetracycline (CTC) antimicrobial use within US Northern Great Plains (NGP) swine-production facilities. Antimicrobial feed-additive use is widespread within this industry and is expected to play an integral role within future carbon-management strategies due to its ability to increase feed efficiency and control disease.