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83 Chapter 4 Life Cycle Assessment The identifi cation of design alternatives that best satisfy environmental demands requires the use of instruments able to quantify the environmental performance of the product under development and guide the ameliorative measures. Moreover, only a systematic vision of the product over its life cycle can ensure that these measures reduce the environmental criticalities and so avoid simply transferring impacts from one phase of the life cycle to another. Life Cycle Assessment (LCA) is an objective procedure used to evaluate the environmental impacts associated with a product’s entire life cycle, through the quantitative determination of all the exchange fl ows between the product– system and the ecosphere in all the transformation processes involved, from the extraction of raw materials to their return into the ecosphere in the form of waste. This chapter provides an overview of Life Cycle Assessment, tracing a general picture from its origins to the latest developments. Having described the premises, principal characteristics, and reference methodological struc- tures, it will be possible to specify its fi elds of application and limitations and to indicate the tools most commonly used in practice. 4.1 Environmental Analysis and Evaluation of the Life Cycle Environmental impact can be defi ned as “any change to the environment, whether adverse or benefi cial, wholly or partially resulting from an organi- zation’s activities, products or services” (ISO 14001, 1996). One of the great- est diffi culties in an attempt to reduce the negative impact that a generic activity has on the environment is that of evaluating this impact qualita- tively or quantitatively, so as to be then able to undertake appropriate initia- tives to contain it. Although the methodologies developed for the evaluation of environmental impact (Environmental Impact Assessment—EIA) are numerous (Jain et al., 1993) and differ in their identifi cation, measurement 2722_C004_r02.indd 832722_C004_r02.indd 83 12/1/2005 1:34:00 PM12/1/2005 1:34:00 PM © 2006 by Taylor & Francis Group, LLC and interpretation of the impact, they generally have some signifi cant limi- tations in common: • They were developed in relation to specifi c cases. • They do not include the possibility of assessing the reliability and stability of the results. • They do not start from the premise of the life cycle approach in line with the ideas expressed in previous chapters. Only the methodology known as Life Cycle Assessment differs with regard to precisely these limitations, in that it overcomes them by an approach to the evaluation of environmental impact based on the premises already consumption of resources and the emission of waste relative to a generic entire life cycle of the product of this activity through the quantitative determination of all the fl ows of exchange between the product–system and the ecosphere necessitated by all the transformation processes involved, from the extraction of raw materials to their return into the ecosphere in the form of waste. 4.1.1 Origins and Evolution The fi rst studies regarding the quantifi cation of the consumption of virgin materials and the energy effi ciency of production processes date back to the 1960s. They were greatly infl uenced by the results of some provisional models of development that described a scenario characterized by a rapid increase in the world population and limited natural resources, with the consequent impoverishment of fossil fuels and mineral resources, accompanied by climate change caused by excessive thermal emissions from the processes of energy transformation (NAS, 1969; Goldsmith et al., 1972). As a direct conse- quence, these studies were mainly oriented toward the evaluation of the costs, and environmental implications associated with conventional energy production and alternative sources of energy, and the effi ciency with which the energy produced was used in industrial processes. While these types of evaluations were based on energy analyses, they nevertheless required the compilation of balance sheets on the fl ows describing the processes under examination. Since the latter could not be separated from the quantifi cation of the consumption of raw materials and the generation of solid waste, these early energy studies were also important analyses of the fl ows of all the resources in play. One of the most signifi cant of these fi rst concrete testimo- nies to the new approach to environmental issues was conducted in the fi eld of industrial chemistry (Smith, 1969). 84 Product Design for the Environment 2722_C004_r02.indd 842722_C004_r02.indd 84 12/1/2005 1:35:16 PM12/1/2005 1:35:16 PM © 2006 by Taylor & Francis Group, LLC noted in Chapter 2. In fact, LCA is an objective procedure to evaluate the industrial activity (see Section 2.4, Figures 2.4 and 2.6). It addresses the Life Cycle Assessment 85 The same period saw the fi rst signifi cant investigation regarding products of mass consumption, consisting of a study conducted by the Midwest Research Institute, and later by Franklin Associates, on behalf of the Coca- Cola Company on different containers for soft drinks (Vigon et al., 1993; Curran, 1996; Hunt and Franklin, 1996). This study is frequently cited as the fi rst example of an inventory analysis of resources and waste undertaken in the United States, since it had the goal of quantifying the raw materials, fuels, and environmental charges correlated with the production processes of each type of container under consideration. Stimulated by the oil crisis of the early 1970s, the process of quantifying the consumption of resources and of the fl ows returning to the environment due to the manufacturing of industrial products began to acquire a defi nite meth- odological structure, becoming known as “Resources and Environmental Profi le Analysis” (REPA) in the United States of America (Hunt et al., 1992). A noted REPA study on drink containers conducted by the U.S. Environmental Protection Agency (Hunt et al., 1974) can be considered a typical forerunner of modern LCA. At the same time, analogous studies in Europe introduced the practice known as “Ecobalance” (Vigon et al., 1993; White and Wagner, 1996). These focused on the consumption of material and energy resources and on the generation of waste, in accord with the issues characterizing the environ- mental debate at a time when information on the emissions of processes, the polluting properties of substances and the potential effects on the environ- ment was still limited. From these fi rst studies, the idea began to take shape that the only effective route for a complete study of industrial production systems from the view- point of their environmental consequences was to examine their operation quantitatively, following the path of the raw materials, beginning with their extraction, through all the transformation processes until their return to the ecosphere under the form of waste (“from cradle to grave”). The main stimulus leading to this approach was the newly acquired under- standing that the traditional approach of concentrating on rendering single production processes more effi cient, without considering the entire system of interrelated activities, was totally inadequate. This result is even more true precisely in relation to the environmental question, since an industrial activity, considered singly, may be made to seem cleaner and more effi cient by simply transferring the pollution elsewhere: the environmental benefi ts derived are counteracted by new environmental criticalities generated at some other part of the same industrial system, without obtaining any real overall improvement. Because the oil crisis was no longer acting as a stimulus during the late 1970s and early 1980s, attention passed from the saving of resources to the management of polluting waste. Nevertheless research continued into the environmental profi les of products and processes, above all regarding two themes: the energy effi ciency of industrial processes (Boustead and Hancock, 1979; Brown et al., 1980); the production and use of packaging in general 2722_C004_r02.indd 852722_C004_r02.indd 85 12/1/2005 1:35:16 PM12/1/2005 1:35:16 PM © 2006 by Taylor & Francis Group, LLC 86 Product Design for the Environment (Bridgwater and Lidgren, 1983; Boustead and Lidgren, 1984) and, in particu- lar, drink containers (Lundholm and Sundstrom, 1985). This last problem was particularly felt in Europe, to such an extent that as soon as a specifi c body of the European Commission was created to address environmental questions (Environment Directorate), attention was immediately centered on the question of the environmental consequences of the production and diffu- sion of containers. A specifi c directive promoted monitoring of the consump- tion of material and energy resources and the generation of solid wastes is associated with this product typology (EC Directive 85/339, 1985). 4.1.2 Introduction of Life Cycle Assessment and Concept Development The defi nitive development of a common methodology for the environmen- tal evaluation of products appeared at the end of the 1980s, and was charac- terized by two successive phases. Initially, the environmental issue of the fl ows of solid waste was emphasized, resulting in the fi eld of interest being extended to recycling and waste disposal, completely fulfi lling the life cycle approach in inventory analysis (Life Cycle Inventory—LCI). Subsequently, there was heightened interest in a transition from inventory analysis alone to a more complete evaluation of the consequences to the environment (Life Cycle Impact Assessment—LCIA). These new stimuli led to the widespread understanding that there was a clear and immediate need for a common structure in the methods of evalua- tion and analysis developed until then. The conference organized by the Society for Environmental Toxicology and Chemistry (SETAC) in Vermont in August 1990 was a direct response to this need. It was here that the term “Life Cycle Assessment” was coined and defi ned as “an objective process to evaluate the environmental burdens associated with a product or activity by identifying and quantifying energy and materials used and wastes released to the environment, and to evaluate and implement opportunities to affect environmental improvements” (Fava et al., 1991). The life cycle approach was expressly highlighted: “The assessment includes the entire life cycle of the product, process, or activity, encompassing extracting and processing raw materials; manufacturing, transportation and distribution; use, reuse, maintenance; recycling and fi nal disposal.” Fr nized by SETAC became an international forum for the discussion of the methodological foundations and more specifi c issues of LCA. One of the subsequent meetings, the workshop held in Portugal in April 1993, is consid- ered particularly important because it saw the fi rst defi nition of common guidelines for conducting an LCA (Consoli et al., 1993). Recognition of the validity and utility of this methodology led, fi nally, to international standardization through the publication, from 1997 on, of the 2722_C004_r02.indd 862722_C004_r02.indd 86 12/1/2005 1:35:17 PM12/1/2005 1:35:17 PM © 2006 by Taylor & Francis Group, LLC om then on, as shown in Figure 4.1, the conferences and workshops orga- Life Cycle Assessment 87 ISO 14040 series of norms (which are integrated into the greater corpus of ISO 14000 standards for Environmental Management Systems). The detailed defi - nition of LCA evidences the implicit intention of the standardization to delin- eate a clear reference methodology considering it a technique for assessing the environmental impacts associated with a product by “compiling an inventory of relevant inputs and outputs of a product system; evaluating the potential environmental impacts associated with those inputs and outputs; interpret- ing the results of the inventory analysis and impact assessment phases in rela- tion to the objectives of the study” (ISO 14040, 1997). As will be illustrated below, the group of ISO 14040 standards describes in detail the general criteria and underlying methodological framework for the main phases making up a complete LCA. Finally, attention should be drawn to one of the most recent important initiatives directed at the dissemination of LCA (Figure 4.1), that of the cooperation between SETAC and the United Nations Environmental Programme (UNEP), set up in 2002 under the name of UNEP/SETAC Life Cycle Initiative (Topfer, 2002). 4.2 Premises, Properties, and Framework of Life Cycle Assessment The ISO 14040 series of standards are based on a preliminary structure that can be ascribed to that defi ned by SETAC in the early 1990s. The most basic defi ni- tion of LCA is a concise summing up of the SETAC proposal, understood as the FIGURE 4.1 Evolution of LCA. 2722_C004_r02.indd 872722_C004_r02.indd 87 12/1/2005 1:35:17 PM12/1/2005 1:35:17 PM © 2006 by Taylor & Francis Group, LLC 88 Product Design for the Environment “compilation and evaluation of the inputs, outputs and the potential environ- mental impacts of a product system throughout its life cycle” (ISO 14040, 1997). The methodological structure is based on several premises: • The analysis of the environmental interactions between the elemen- tary activities of the product–system starts from the “cradle to grave” perspective. • The approach to the life cycle is holistic in the sense fully discussed in previous chapters. • The analysis of the effects on the environment are based on a multi- criteria perspective, in that it evaluates the whole panorama of cate- gories of environmental impact and damage that may result from interactions with the product–system. • The evaluation and comparison of activities are related to a functional unit and, therefore, are in line with the principle of equivalence for equal functionality produced (i.e., requiring the preliminary defi ni- tion of a reference functional unit, quantifying the unit of product– system performance). 4.2.1 Defi nition of Life Cycle and Product–System The ISO standard defi nition of life cycle also fully refl ects the SETAC outline and the concepts discussed in previous chapters. In fact, it defi nes the life cycle of a product as “consecutive and interlinked stages of a product system, from raw material acquisition or generation of natural resources to the fi nal disposal.” The product–system is understood to be the “collection of materi- ally and energetically connected unit processes which perform one or more defi ned functions” (ISO 14040, 1997). Again, the subdivision of the main phases of the life cycle according to the conventional structuring of LCA (Fava et al., 1991) is substantially analogous • Raw Material Acquisition—Includes all the activities and processes required to obtain material and energy resources from the environ- ment, starting from the extraction of raw materials. • Processing and Manufacturing—Includes all the activities and processes required to transform resources into the desired product. • Distribution—Includes all the activities of transport, storage, and distribution that allow the product to arrive at the customer. • Use, Maintenance, Repair—Includes the entire phase of product use, including all typologies of servicing operations. 2722_C004_r02.indd 882722_C004_r02.indd 88 12/1/2005 1:35:17 PM12/1/2005 1:35:17 PM © 2006 by Taylor & Francis Group, LLC to that described in Chapter 2: Life Cycle Assessment 89 • Recycle—Follows the phase of product use and includes all the recy- cling options, both internal (closed loop) and external (open loop) to the life cycle of origin. • Waste Management—Concerns the nonrecyclable fraction of the product and consists of the management of fi nal waste disposal. Together, these phases constitute the complete system “from cradle to grave.” However, it is possible to conduct partial LCA, defi ning one or more levels (gates) at which the complete system is interrupted so that LCA can be broken down into additional variants (Todd, 1996): • Cradle to Gate—Analysis of the portion of life cycle upstream from the gate • Gate to Grave—Analysis of the portion of life cycle downstream from the gate • Gate to Gate—Analysis of the portion of life cycle between two gates 4.2.2 Methodological Framework of LCA As was seen in Section 4.1, the fi rst examples of LCA fundamentally consisted of the quantifi cation of the material and energy resources in play and of the resulting solid waste. With respect to these fi rst studies, the environmental requirements have changed, as has the level of completeness and refi nement of the environmental analysis of the life cycle. This level has been raised considerably, starting from the fi rst methodological structuring (Fava et al., 1991; Consoli et al., 1993) and subsequent developments (Vigon et al., 1993; Fava et al., 1993; EPA, 1995) to arrive at the fi nal form defi ned by the ISO standards. The main methodological frameworks predating the ISO standardization present state of development of the LCA framework (according to the ISO standards, in particular with regard to the phases of Life Cycle Inventory and Life Cycle Impact Assessment) has recently been proposed (Rebitzer et al., 2004; Pennington et al., 2004) in studies evidencing the key issues still under debate and the main fi elds of practical application of LCA in its current state. At the present time, a complete LCA is structured in four main stages: • Goal and Scope Defi nition—The objectives of the analysis and the set of preliminary assumptions according to which it will be conducted are defi ned in this fi rst phase. This requires the defi nition of the evaluation typology (aimed at system improvement or compar- ing alternative systems); the boundaries of the system under exami- nation; the reference functional unit, assumptions, and parameters 2722_C004_r02.indd 892722_C004_r02.indd 89 12/1/2005 1:35:18 PM12/1/2005 1:35:18 PM © 2006 by Taylor & Francis Group, LLC are summarized in Table 4.1 (see also Figure 4.1). A complete panorama of the 90 Product Design for the Environment for inventory and allocation operations; and the categories of impact to be considered. • Life Cycle Inventory (LCI)—Includes the compilation and quantifi - cation of the inputs and outputs of the entire life cycle. The data can be obtained from various sources such as direct measurement as well as information from databases and the literature. • Life Cycle Impact Assessment (LCIA)—Constitutes the phase of LCA where the inventory data are translated into potential environmental impacts, evaluating their size and signifi cance. The conventional procedure consists of classifying the inventory fl ows (Classifi cation) and characterizing them quantitatively in relation to different impact categories (Characterization). Impact categories include ozone depletion, acidifi cation, eutrophication, climate change, depletion of resources, etc. In Classifi cation, the inputs and outputs identifi ed in LCI are assigned to impact categories. In Characterization, the impact potentials of each consumption or emission are calculated by multiplying the quantity consumed or emitted by the respective TABLE 4.1 LCA methodological frameworks prior to ISO standards METHODOLOGICAL FRAMEWORK YEAR REFERENCES SETAC Society of Environmental Toxicology and Chemistry 1990 (Fava et al., 1991) (Consoli et al., 1993) CML University of Leiden The Netherlands 1992 (Heijungs et al., 1992) (Guinée, 2002) (updated after ISO 14040) EPS IVL Environmental Research Institute Sweden 1992 (Steen, 1996) (Steen, 1999) (updated after ISO 14040) US EPA Environmental Protection Agency United States 1993 (Vigon et al., 1993) (EPA, 1995) EIO-LCA Carnegie Mellon University United States 1995 (Cobas et al., 1995) (Hendrickson et al., 1998) NORDIC GUIDELINES Nordic Council of Ministers Denmark 1995 (Lindfors et al., 1995) UNEP United Nations Environment Programme 1996 (UNEP, 1996) EDIP Technical University of Denmark and Danish Environmental Protection Agency Denmark 1997 (Wenzel et al., 1997) 2722_C004_r02.indd 902722_C004_r02.indd 90 12/1/2005 1:35:18 PM12/1/2005 1:35:18 PM © 2006 by Taylor & Francis Group, LLC Life Cycle Assessment 91 impact assessment factor (or characterization factor) relative to each impact category. The resulting impact data are then normalized (Normalization) and weighted (Weighting), to obtain single indices of environmental impact. • Interpretation (according to ISO) or Improvement Analysis (accord- ing to SETAC)—In this fi nal phase, the results of the LCA or LCIA are evaluated in relation to the planned objectives in order to formu- late fi nal considerations and directives for improvement. For an overview of the parameters to be quantifi ed in an inventory analysis, reference should be made to the considerations regarding the environmental impact of the product-system discussed in Section 2.3 (and, in particular, to evaluating environmental effects are also presented. The organization into four main stages is common to both the fi rst method- ological framework of LCA proposed by SETAC and the standardization defi ned in the international ISO norms (Figure 4.2). The only signifi cant differences can be found in the phase of evaluating the impacts (LCIA) and in the fi nal phase (Interpretation or Improvement). Regarding the LCIA phase, the SETAC structure differs from the ISO standard in that: • In the SETAC method, impact assessment is structured more rigidly, providing for not only Classifi cation and Characterization, but also a fi nal action of Valuation, where weighting procedures are applied to FIGURE 4.2 LCA framework and impact assessment according to SETAC and ISO 14040. 2722_C004_r02.indd 912722_C004_r02.indd 91 12/1/2005 1:35:18 PM12/1/2005 1:35:18 PM © 2006 by Taylor & Francis Group, LLC Figure 2.3), where some introductory indications regarding the problem of 92 Product Design for the Environment the different impact typologies with the aim of obtaining data for comparison or aggregation. These data are used as the basis for deciding on the actions to be taken (Fava et al., 1993). • In the ISO standard, there is a sharp distinction between obligatory and optional procedures. The choice of the environmental effects to be taken into consideration (Selection), Classifi cation, and Characteri- zation are all obligatory. The optional procedures (Normalization, Grouping, and Weighting) concern the elaboration of the results of the Characterization phase to obtain concise indices that can be used to obtain an overall evaluation (ISO 14043, 2000). With regard to the fi nal phase, the SETAC structure differs from the ISO stan- dard in that: • In the SETAC method, this is indicated as Improvement Analysis and focuses attention on the possibility of formulating interventions to improve environmental performance (Fava et al., 1991). • In the ISO standard, it is indicated as Interpretation and involves a more extensive intervention, including sensitivity analysis and assessment of the uncertainty of the results, and the formulation of fi nal recommendations (ISO 14043, 2000). 4.2.3 Phases of LCA in ISO Standards The ISO 14040 series of standards includes all the main phases comprising of their specifi c contents. The lower section of the table also reports informa- tion on technical reports and preliminary documents belonging to the same group, but not yet made normative. This section presents a more detailed discussion of the standards published to date and held to be of particular importance in providing a more complete picture of the current scope and features of the methodological approach to LCA. 4.2.3.1 ISO 14040:1997—Principles and Framework This standard focuses on some important preliminary questions: • Goal and scope—The objectives and range of an LCA must be clearly defi ned and coherent with the intended application. An explicit statement of the purposes of the study is, therefore, essential. • Functional unit—This is a reference unit of measurement used to treat and present the data and information of an LCA. According to the norm, a functional unit constitutes “a measure of the performance of 2722_C004_r02.indd 922722_C004_r02.indd 92 12/1/2005 1:35:18 PM12/1/2005 1:35:18 PM © 2006 by Taylor & Francis Group, LLC LCA. Table 4.2 shows the main headings of these standards and a summary [...]... Inventory Analysis, ISO 140 41: 1998(E), International Organization for Standardization, Geneva, 1998 ISO 140 42, Environmental Management Life Cycle Assessment Life Cycle Impact Assessment, ISO 140 42:2000(E), International Organization for Standardization, Geneva, 2000 ISO 140 43, Environmental Management Life Cycle Assessment Life Cycle Interpretation, ISO 140 43:2000(E), International Organization for Standardization,... International Standard 2000 Environmental management: Life Cycle assessment Life cycle impact assessment ISO 140 43:2000 International Standard 2000 Environmental management: Life Cycle assessment Life cycle interpretation ISO/TR 140 47 Technical Report 2003 Environmental management: Life Cycle assessment— Examples of application of ISO 140 42 Environmental management: Life Cycle assessment— Data documentation... under examination The methods of normalization and weighting are varied and not standardized—each refers to different parameters, often linked to artificial and debatable considerations (ISO 140 42, 2000) 4. 2.3 .4 ISO 140 43: 2000 Life Cycle Interpretation The last phase of LCA provides for the interpretation of the data obtained in the preceding phases and, on the basis of this data, identifying the actions... detailed) evaluation of the product s impact in the early phases of design This approach is intended to overcome the main drawbacks of a Full LCA, which are: • The complexity and length of the analysis and evaluation process, contrasting with the ever-more-pressing need to reduce the product s time-to-market • The necessity of using a considerable mass of data, usually not available in the first phases... Life Cycle Assessment TABLE 4. 2 ISO international standards and technical reports for LCA DESIGNATION DOCUMENT TYPE YEAR TITLE CONTENTS ISO 140 40:1997 International Standard 1997 ISO 140 41:1998 International Standard 1998 Environmental management: Life Cycle assessment— Principles and framework Environmental management: Life Cycle assessment— Goal and scope definition and inventory analysis ISO 140 42:2000... compensate for the incompleteness of analysis techniques that reduce the product system to a process-based system, like LCA On the other hand, process-based analysis maintains its primacy in terms of the level of detail and specificity of the processes, a characteristic lacking in the IOA approach A well-known example of the use of input–output analysis as a methodological structure for the environmental... Cycle assessment— Examples of application of ISO 140 41 to goal and scope definition and inventory analysis Requirements and a structure for a data documentation format, to be used for transparent and unambiguous documentation and exchange of LCA and LCI data Examples of practices in carrying out a LCI as a means of satisfying certain provisions of ISO 140 41 © 2006 by Taylor & Francis Group, LLC 2722_C0 04_ r02.indd... Organization for Standardization, Geneva, 1996 ISO 140 40, Environmental Management Life Cycle Assessment—Principles and Framework, ISO 140 40:1997(E), International Organization for Standardization, Geneva, 1997 © 2006 by Taylor & Francis Group, LLC 2722_C0 04_ r02.indd 106 12/1/2005 1:35:20 PM Life Cycle Assessment 107 ISO 140 41, Environmental Management Life Cycle Assessment—Goal and Scope Definition and... 98 Product Design for the Environment environmental performance The evaluations are, therefore, more objective and verifiable, but require more detailed information that can only be obtained after a certain point of the design process has been reached Conversely, the qualitative instruments are based on mostly subjective observations and evaluations They are, therefore, easy to implement because they... EPA -4 5 2/R-95–002, U.S Environmental Protection Agency, Office of Air Quality Planning and Standards, Research Triangle Park, NC, 1995 Ernzer, M and Wimmer, W., From environmental assessment results to design for environment product changes: An evaluation of quantitative and qualitative methods, Journal of Engineering Design, 13(3), 233– 242 , 2002 Fava, J et al., A Technical Framework for Life- Cycle Assessment, . Alternatively, again in order to facili- tate the information-gathering phase, it is possible to use surrogate data as well as both quantitative and qualitative data. In practice, numerous strat- agems. Taylor & Francis Group, LLC LCA. Table 4. 2 shows the main headings of these standards and a summary Life Cycle Assessment 93 TABLE 4. 2 ISO international standards and technical reports for. Inventory analysis (LCI) ISO 140 42:2000 International Standard 2000 Environmental management: Life Cycle assessment Life cycle impact assessment General framework for the Life Cycle Impact Assessment

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