Life cycle considerations of the flue gas desulphurization system at a lignite-fired power plant in Thailand

Goal, Scope and Background  The Flue Gas Desulphurization (FGD) system has been installed at the biggest lignite-fired power generation plant in Thailand to reduce the large amount of SO₂ emission. In order to understand the costs and benefits, both in ecological and economic terms, the lignite-fired plant was studied both before and after the installation of the FGD system. The focus of this study is to consider not only the Life Cycle Assessment (LCA) outcome but also the Life Cycle Costing (LCC) factors. The results can provide valuable information when selecting appropriate technologies to minimize the negative impact that lignite-fired power plants have on the environment. Methods  The Life Cycle Assessment - Numerical Eco-load Total Standardization (LCA-NETS) system was used to evaluate the impact on the environment of both the lignite-fired plant and the FGD system. Life Cycle Costing (LCC) was used to provide a comparison between alternative before and after installation of FGD. LCC, a powerful analytical tool, examines the total cost, in net present value terms, of a FGD system over its entire service lifetime. Results and Discussion  The results of the study are shown in the eco-load values over the entire life cycle of the lignite-fired plant. Comparative models of the power plant, before and after the installation of the FGD system, are evaluated using the LCA-NETS system. The results indicate that the installation of the FGD system can reduce the acidification problem associated with lignite-fired plants by approximately 97%. The LCC estimation shows the major costs of the FGD system: capital investment, operating and maintenance, and miscellaneous costs. The LCC provides the decision-making information when considering the cost of the FGD system in terms of protecting the environment. Conclusion and Outlook  LCA is an important decision-making tool for environmental policies, especially with regard to the selection of pollution control equipment for lignite-fired plants. Green coal technologies and strategies to reduce the negative impact on the environment are essential to produce more environmentally-friendly power plants with a sustainable future.     

农业生命周期评价研究进展

作为评价产品系统全链条环境影响的有效工具,生命周期评价（LCA）方法已广泛用于工业领域。农业领域也面临着高强度的资源和环境压力,LCA在农业领域的应用应运而生。旨在综述已有农业LCA研究的基础上,鉴别农业LCA应用存在的问题,并为农业LCA未来的发展提出建议。目前农业LCA存在系统边界和功能单位界定不明晰、缺少区域清单数据库、生命周期环境影响评价模型（LCIA）不能准确反映农业系统环境影响、结果解释存在误区等方面的问题。为了科学准确地衡量农业系统的环境影响,促进农业系统的可持续发展,文章认为农业LCA应该从以下几个方面加强研究,即科学界定评价的参照系、系统边界的扩大及功能单位的合理选取、区域异质性数据库构建与LCIA模型开发、基于组织农业LCA的开发以及对于利益相关者行为的研究。     

Life Cycle Tools within Ford of Europe's Product Sustainability Index. Case Study Ford S-MAX & Ford Galaxy (8 pp)

Background, Aim and Scope Sustainability is a well recognised goal which is difficult to manage due to its complexity. As part of a series of sustainability management tools, a Product Sustainability Index (PSI) is translating the sustainability aspects to the organization of vehicle product development of Ford of Europe, thus allocating ownership and responsibility to that function. PSI is limiting the scope to those key environmental, social and economic characteristics of passenger vehicles that are controllable by the product development organisation. Materials and Methods: The PSI considers environmental, economic and social aspects based on externally reviewed life cycle environmental and cost aspects (Life Cycle Assessment, Cost of ownership / Life Cycle Costing), externally certified aspects (allergy-tested interior) and related aspects as sustainable materials, safety, mobility capability and noise. After the kick-off of their product development in 2002, the new Ford S-MAX and Ford Galaxy are serving as a pilot for this tool. These products are launched in Europe in 2006. The tracking of PSI performance has been done by engineers of the Vehicle Integration department within the product development organization. The method has been translated in an easy spreadsheet tool. Engineers have been trained within one hour trainings. The application of PSI by vehicle integration followed the principle to reduce the need for any incremental time or additional data to a minimum. PSI is adopted to the existing decision-making process. End of 2005, an internal expert conducted a Life Cycle Assessment and Life Cycle Costing (LCC) study for verification purposes using commercial software. This study and the PSI have been scrutinized by an external review panel according to ISO14040 and, by taking into consideration the on-going SETAC, work in the field of LCC. Results: The results of the Life Cycle based indicators of PSI as calculated by non-experts are fully in line with those of the more detailed expert study. The difference is below 2%. The new Ford Galaxy and Ford S-MAX shows significantly improved performance regarding the life cycle air quality, use of sustainable materials, restricted substances and safety compared to the previous model Galaxy. The affordability (Life Cycle Cost of Ownership) has also been improved when looking at the same engine types. Looking at gasoline versus diesel options, the detailed study shows under what conditions the diesel options are environmentally preferable and less costly (mileage, fuel prices, etc.). Discussion: The robustness of results has been verified in various ways. Based also on Sensitivity and Monte-Carlo Analysis, case study-specific requirements have been deduced defining criteria for a significant environmental improvement between the various vehicles. Only if the differences of LCIA results between two vehicles are larger than a certain threshold are the above-mentioned results robust. Conclusions: In general terms, an approach has been implemented and externally reviewed that allows non-experts to manage key environmental, social and economic aspects in the product development, also on a vehicle level. This allows mainstream functions to take ownership of sustainability and assigns accountability to those who can really decide on changes affecting the sustainability performance. In the case of Ford S-MAX and Galaxy, indicators from all three dimensions of sustainability (environment, social and economic) have been improved compared to the old Ford Galaxy. Recommendations and Perspectives: Based on this positive experience, it is recommended to make, in large or multinational organizations, the core business functions directly responsible and accountable for managing their own part of environmental, social and economic aspects of sustainability. Staff functions should be limited to starting the process with methodological and training support and making sure that the contributions of the different main functions fit together.     

Eco-efficiency

Goal, Scope and Background The eco-efficiency analysis and portfolio is a powerful decision support tool for various strategic and marketing issues. Since its original academic development, the approach has been refined during the last decade and applied to a multitude of projects. BASF, as possibly the most prominent company using and developing this tool, has applied the eco-efficiency approach to more than 300 projects in the last 7 years. One of the greatest difficulties is to cover both dimensions of eco-efficiency (costs or value added and environmental impact) in a comparable manner. This is particularly a challenge for the eco-efficiency analyses of products. Methods In this publication, an important approach and field of application dealing with product decisions based on the combination of Life Cycle Cost (LCC) and Life Cycle Assessment (LCA) is described in detail. Special emphasis is put on the quantitative assessment of the relation of costs and environmental impacts. In conventional LCA an assessment of environmental impact categories is often made by normalization with inhabitant equivalents. This is necessary to be able to compare the different environmental impact categories, because of each different unit. For the proposed eco-efficiency analysis, the costs of products or processes are also normalized with adapted gross domestic product figures. Results and Discussion The ratio between normalized environmental impact categories and normalized costs (R_E,C) is used for the graphical presentation of the results in an eco-efficiency portfolio. For the interpretation of the results of an eco-efficiency analysis, it is important to distinguish ratios R_E,C which are higher than one from ratios lower than one. In the first case, the environmental impact is higher than the cost impact, while the inverse is true in the second case. This is very important for defining which kind of improvement is needed and defining strategic management decisions. The paper shows a statistical evaluation of the R_E,C factor based on the results of different eco-efficiency analyses made by BASF. For industries based on large material flows (e.g. chemicals, steel, metals, agriculture), the R_E,C factor is typically higher than one. Conclusions and Recommendations This contribution shows that LCC and LCA may be combined in a way that they mirror the concept of eco-efficiency. LCAs that do not consider LCC may be of very limited use for company management. For that very reason, corporations should install a data management system that ensures equal information on both sides of the eco-efficiency coin.     

基于生命周期方法的生活垃圾资源化利用系统生态效率分析

我国生活垃圾产量大但处理能力不足,产生多种环境危害,对其资源化利用能够缓解环境压力并回收资源。为探讨生活垃圾资源化利用策略,综合生命周期评价与生命周期成本分析方法,建立生态效率模型。以天津市为例,分析和比较焚烧发电、卫生填埋-填埋气发电、与堆肥+卫生填埋3种典型生活垃圾资源化利用情景的生态效率。结果表明,堆肥+卫生填埋情景具有潜在最优生态效率;全球变暖对总环境影响贡献最大,而投资成本对经济影响贡献最大。考虑天津市生活垃圾管理现状,建议鼓励发展生活垃圾干湿组分分离及厨余垃圾堆肥的资源化利用策略。     

Using anticipatory life cycle assessment to enable future sustainable construction

The built environment is the largest single emitter of CO₂ and an important consumer of energy. Much research has gone into the improved efficiency of building operation and construction products. Life Cycle Assessment (LCA) is commonly used to assess existing buildings or building products. Classic LCA, however, is not suited for evaluating the environmental performance of developing technologies. A new approach, anticipatory LCA (a‐LCA), promises various advantages and can be used as a design constraint during the product development stage. It helps overcome four challenges: (i) data availability, (ii) stakeholder inclusion, (iii) risk assessment, and (iv) multi‐criteria problems. This article's contribution to the line of research is twofold: first, it adapts the a‐LCA approach for construction‐specific purposes in theoretical terms for the four challenges. Second, it applies the method to an innovative prefabricated modular envelope system, the CleanTechBlock (CTB), focusing on challenge (i). Thirty‐six CTB designs are tested and compared to conventional walls. Inclusion of technology foresight is achieved through structured scenario analysis. Moreover, challenge (iv) is tackled through the analysis of different environmental impact categories, transport‐related impacts, and thickness of the wall assemblies of the CTB. The case study results show that optimized material choice and product design is needed to reach the lowest environmental impact. Methodological findings highlight the importance of context‐specific solutions and the need for benchmarking new products.     

Life cycle inventory analysis - A case study of steel used in Brazilian automobiles

Data acquisition to perform LCA is time and capital consuming. There is already international data about environmental aspects in several processes. This study aims to verify the possibility of adapting international data to Brazilian conditions. Therefore, a Life Cycle Inventory was conducted to compare the use of national and international data for steel used in automobiles. This was done in three steps: objective and scope definition, inventory analysis and interpretation. LCI is a simplification of Life Cycle Assessment (LCA) as impact assessment is not taken into account. Even so, LCI takes into account all life cycle stages of a product, that is, from its extraction through its deposition. In this study, three phases of the life cycle were considered: steel manufacturing, automobile use and disposal. In the case studied, the amount of steel evaluated was 263 kg, which would be possible to be replaced by other materials in a 1,300 kg automobile. Resources and energy consumption, atmospheric emissions and solid residues production were taken into account within the analysis done. Results show that automobile use and materials manufacturing are responsible for the bulk of energy and resources consumption. Solid residues occur mainly in the discard phase, due to the low level of recycling. Several differences were also achieved between national and international data, which implies the need of environmental databases development.     

Comparative LCA of industrial objects

Goal, Scope and Background  This paper is the second part of the publication which is devoted to comparative LCA analysis of the industrial pumps. The previous paper deals with the methodological aspects concerning quality assessment and forms an independent work. This paper uses practically only the methodological suggestions made there. The main aim of the presented study is to make a comparison between the industrial pumps which are based on two different technologies. The Life Cycle Assessment method is used to check whether the differences of the manufacturing processes influence the level of the potential environmental impact during the whole life cycle of the analysed products. Methods  The Life Cycle Assessment is carried out using the Ecoindicator99 method. Additionally, an extensive quality analysis of the LCA study is made (Part I). To make the process of an identification of the data easier and faster, they are assigned to a special data documentation form. To ensure the credibility of the LCA results different methods of interpretation are used. Results and Discussion  The LCA analysis shows clear superiority of the pumps manufactured using modern technology. It seems that this superiority results not only from the differences in the emissions, but also from different characteristics of effectiveness in the usage stage. Thanks to the uncertainty analysis, each LCA result is provided with the range of uncertainty. Conclusions  The LCA results are supported by different techniques of interpretation: the sensitivity-, the contribution-, the comparative-, the discernability- and the uncertainty analysis. There is strong evidence of the superiority of the pumps based on the modern technology. Recommendations and Outlook  The main source of the environmental impact in the case of pumps is the usage stage and the consumption of energy. That is why it should be the main area to improve. The LCA results show that actions taken in the usage stage and energy consumption can lead to a considerable reduction of the environmental impacts.     

中国生命周期评价理论与实践研究进展及对策分析

主要分析了我国生命周期评价的理论与实践研究进展与数据库构建现状,针对当前我国生命周期评价理论与应用研究的关键薄弱环节即不确定性分析、本土化数据库构建、本土化生命周期环境影响评价模型构建,指出了利用泰勒系列展开模型进行符合我国产业链生产现状的精确、完整、具有代表性、具有时空动态特征的生命周期数据库构建的必要性;并指出需要根据我国国情(例如:环境、地理、人口、暴露等)来构建生命周期环境影响评价模型的紧迫性。     

Enhancing life cycle impact assessment from climate science: Review of recent findings and recommendations for application to LCA

Since the Global Warming Potential (GWP) was first presented in the Intergovernmental Panel on Climate Change (IPCC) First Assessment Report, the metric has been scrutinized and alternative metrics have been suggested. The IPCC Fifth Assessment Report gives a scientific assessment of the main recent findings from climate metrics research and provides the most up-to-date values for a subset of metrics and time horizons. The objectives of this paper are to perform a systematic review of available midpoint metrics (i.e. using an indicator situated in the middle of the cause-effect chain from emissions to climate change) for well-mixed greenhouse gases and near-term climate forcers based on the current literature, to provide recommendations for the development and use of characterization factors for climate change in life cycle assessment (LCA), and to identify research needs. This work is part of the ‘Global Guidance on Environmental Life Cycle Impact Assessment’ project held by the UNEP/SETAC Life Cycle Initiative and is intended to support a consensus finding workshop. In an LCA context, it can make sense to use several complementary metrics that serve different purposes, and from there get an understanding about the robustness of the LCA study to different perspectives and metrics. We propose a step-by-step approach to test the sensitivity of LCA results to different modelling choices and provide recommendations for specific issues such as the consideration of climate-carbon feedbacks and the inclusion of pollutants with cooling effects (negative metric values).     

碳足迹核算的国际标准概述与解析

各种层面上的碳足迹核算在全球气候变化控制领域得到了越来越多的关注。但是,这些关于碳足迹核算的相关国际标准繁多,彼此之间的关系复杂,不利于研究领域和工业界对这些标准进行应用与交流,限制了碳足迹核算的发展进度与深度。对目前已有的国际主要碳足迹核算标准及生命周期评价标准进行了整理,梳理出这些国际标准的一些基本特征,绘制了国际标准之间的关系图;并进一步从生命周期评价步骤的角度出发,解析了各种国际标准在这些阶段上的相关内容,以及每一个阶段上各标准相关规定中的不同特点及逻辑关系。对促进我国碳足迹核算相关研究与实践工作具有一定的理论与现实参考意义。     

Life Cycle costing as part of design for environment environmental business cases

Background  In developing products various requirements have to be integrated including functionality, quality, affordability as well as environmental aspects. Often conflicting requirements have to be fulfilled. Therefore, multi-dimensional decision support approaches are necessary. Methods  Here, one approach is to relate the conflicting requirements to each other. Life Cycle Costing (LCC) has the potential to support the trade-off between some environmental targets and overall affordability targets by including all monetary flows along the product life cycle (going beyond the well-known costs of ownership by integrating also long-term use and end-of-life costs). Those solutions can be identified that (a) have the highest efficiencies (where do we get most environmental improvements per Ϊ and (b) have the highest affordability for the customer along the life cycle. Furthermore, on-costs in the design phase can be justified in terms of future savings either for the customer or for the recycling of the products. These represent real business cases for environmental actions. Three types of environmental business cases can be differentiated. Results and Discussion  This paper presents various examples where LCC is integrated into product design. However, there are a number of open issues in the implementation of LCC within real product development including data availability and uncertainty (future costs/ savings), level of discounting, accounting and compensation. Various internal case studies done in the last years showed that already few changes in the costs structure can significantly affect the identi-fied future costs. Recommendation and Outlook  Uncertainties in LCC are higher than in LCA and highest when applied in the stage of product develop-ment, i.e. used to support DfE action. As a consequence, the result-ing figures can only be seen as directional. Therefore, the use of LCC in Design for Environment cannot be recommended without major restrictions in terms of guidance, experience/training. The link-age between LCC and DfE can either be established via (1) experts supporting design teams or (2) as part of a DfE tool. The DfE tool has to include detailed guidance for interpretation, and its application should be based on a solid training for DfE engineers.     

Methodological Aspects of Applying Life Cycle Assessment to Industrial Symbioses

In view of recent studies of the historical development and current status of industrial symbiosis (IS), life cycle assessment (LCA) is proposed as a general framework for quantifying the environmental performance of by‐product exchange. Recent guidelines for LCA (International Reference Life Cycle Data System [ILCD] guidelines) are applied to answer the main research questions in the IS literature reviewed. A typology of five main research questions is proposed: (1) analysis, (2) improvement, and (3) expansion of existing systems; (4) design of new eco‐industrial parks, and (5) restructuring of circular economies. The LCA guidelines were found useful in framing the question and choosing an appropriate reference case for comparison. The selection of a correct reference case reduces the risk of overestimating the benefits of by‐product exchange. In the analysis of existing systems, environmentally extended input‐output analysis (EEIOA) can be used to streamline the analysis and provide an industry average baseline for comparison. However, when large‐scale changes are applied to the system, more sophisticated tools are necessary for assessment of the consequences, from market analysis to general equilibrium modeling and future scenario work. Such a rigorous application of systems analysis was not found in the current IS literature, but would benefit the field substantially, especially when the environmental impact of large‐scale economic changes is analyzed.     

Integrated municipal waste management systems: An indicator to assess their environmental and economic sustainability

Tools based on Life Cycle Thinking (LCT) are routinely used to assess the environmental and economic performance of integrated municipal solid waste (MSW) management systems. Life Cycle Assessment (LCA) is used to quantify the environmental impacts, whereas Life Cycle Costing (LCC) allows financial and economic assessments. These tools require specific experience and knowledge, and a large amount of data.The aim of this project is the definition of an indicator for the assessment of the environmental and economic sustainability of integrated MSW management systems. The challenge is to define a simple but comprehensive indicator that may be calculated also by local administrators and managers of the waste system and not only by scientists or LCT experts.The proposed indicator is a composite one, constituted by three individual indicators: two of them assess the environmental sustainability of the system by quantifying the achieved material and energy recovery levels, while the third one quantifies the costs. The composite indicator allows to compare different integrated MSW management systems in an objective way, and to monitor the performance of a system over time.The calculation of the three individual indicators has been tested on the integrated MSW management systems of the Lombardia Region (Italy) as well as on four of its provinces (Milano, Bergamo, Pavia, and Mantova).     

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.     

Ecological Toxicity Methods and Metals. An examination of two case studies (8 pp + 1)

Goal, Scope and Background The Apeldoorn Workshop (April 15th, 2004, Apeldoorn, NL) brought together specialists in LCA and Risk Assessment to discuss current practices and complications of the life cycle impact assessment (LCIA) ecological toxicity (ecotox) methodologies for metals. The consensus was that the LCIA methods currently available do not appropriately characterize impacts of metals due to lack of fundamental metals chemistry in the models. A review of five methods available to perform ecotox impact assessment for metals has been prepared to provide Life Cycle Assessment (LCA) practitioners with a better understanding of the current state of the science and potential biases related to metals. The intent is to provide awareness on issues related to ecotox impact assessment. Methods In this paper two case studies, one a copper based product (copper tube), the other a zinc-based product (gutter systems), were selected and examined by applying freshwater ecological toxicity impact models – USES-LCA, Eco-indicator 99 (EI 99), IMPACT 2002, EDIP 97, and CalTOX-ETP. Both studies are recent, comprehensive, cradle-to-gate, and peer-reviewed. The objective is to review the LCIA results in the context of the practical concerns identified by the Apeldoorn Declaration, in particular illustrating any inconsistencies such as chemical characterization coverage, species specificity, and relative contribution to impact results. Results and Discussion The results obtained from all five of the LCIA methods for the copper tube LCI pointed to the same substance as being the most important – copper. This result was obtained despite major fundamental differences between the LCIA methods applied. However, variations of results were found when examining the freshwater ecological toxicity potential of zinc gutter systems. Procedural difficulties and inconsistencies were observed. In part this was due to basic differences in model nomenclature and differences in coverage (IMPACT 2002+ and EDIP 97 contained characterization factors for aluminium that resulted in 90% and 22% contribution to burden respectively, the other three methods did not). Differences were also observed relative to the emissions source compartment. In the case of zinc, air emissions were found to be substantial for some ecotox models, whereas, water emissions results were found to be of issue for others. Conclusions This investigation illustrates the need to proceed with caution when applying LCIA ecotox methodologies to life cycle studies that include metals. Until further improvements are made, the deficiencies should be clearly communicated as part of LCIA reporting. Business or policy decisions should not without further discussion be based solely on the results of the currently available methods for assessing ecotoxicity in LCIA. Outlook The outlook to remedy deficiencies in the ecological toxicity methods is promising. Recently, the LCIA Toxic Impacts Task Force of the UNEP/SETAC Life Cycle Initiative has formed a subgroup to address specific issues and guide the work towards establishment of sound characterization factors for metals. Although some measure of precision of estimation of potential impact has been observed, such as in the case of copper, accuracy is also a major concern and should be addressed. Further investigation through controlled experimentation is needed, particularly LCIs composed of a variety of inorganics as well as organics constituents. Support for this activity has come from the scientific community and industry as well. Broader aspects of structure and nomenclature are being collectively addressed by the UNEP/SETAC Life Cycle Initiative. These efforts will bring practical solutions to issues of naming conventions and LCI to LCIA flow assignments.     

Geographical and technological differences in life cycle inventories shown by the use of process models for waste incinerators part I. technological and geographical differences

Goal and Background  Geographical and technological differences in Life Cycle Inventory data are an important source for uncertainty in the result of Life Cycle Assessments. Knowledge on their impact on the result of an LCA is scarce, and also knowledge on how to manage them in an LCA case study. Objective  Goal of this paper is to explore these differences for municipal solid waste incinerator plants, and to develop recommendations for managing technological and geographical differences. Methodology  The paper provides a definition of technological and geographical differences, and analyses their possible impacts. In a case study, the differences are caused intentionally in ‘games’, by virtually transplanting incineration plants to a different location and by changing parameters such as the composition of the waste input incinerated. The games are performed by using a modular model for municipal solid waste incinerator plants. In each case, an LCA including an Impact Assessment is calculated to trace the impact of these changes, and the results are compared. Conclusions  The conclusions of the paper are two-fold: (1) reduce the differences in inventory data where their impact on the result is high; where it is possible reducing them to a great extent, and the effort for performing the change acceptable; in the case of incineration plants: Adapt the flue gas treatment, especially a possible DeNOx step, to the real conditions; (2) make use of modular process models that allow adapting plant parameters to better meet real conditions, but be aware of possible modelling errors. The paper invites the scientific community to validate the model used for a waste incinerator plant, and suggest putting up similar models for other processes, preferably those of similar relevance for Life Cycle Inventories.     

Scenario Modelling in Prospective LCA of Transport Systems. Application of Formative Scenario Analysis (11 pp)

Background Tools and methods able to cope with uncertainties are essential for improving the credibility of Life Cycle Assessment (LCA) as a decision support tool. Previous approaches have focussed predominately upon data quality. Objective and Scope. An epistemological approach is presented conceptualising uncertainties in a comparative, prospective, attributional LCA. This is achieved by considering a set of cornerstone scenarios representing future developments of an entire Life Cycle Inventory (LCI) product system. We illustrate the method using a comparison of future transport systems. Method Scenario modelling is organized by means of Formative Scenario Analysis (FSA), which provides a set of possible and consistent scenarios of those unit processes of an LCI product system which are time dependent and of environmental importance. Scenarios are combinations of levels of socio-economic or technological impact variables. Two core elements of FSA are applied in LCI scenario modelling. So-called impact matrix analysis is applied to determine the relationship between unit process specific socio-economic variables and technology variables. Consistency Analysis is employed to integrate unit process scenarios, based on pair-wise ratings of the consistency of the levels of socio-economic impact variables of all unit processes. Two software applications are employed which are available from the authors. Results and Discussion The study reveals that each possible level or development of a technology variable is best conceived of as the impact of a specific socio-economic (sub-) scenario. This allows for linking possible future technology options within the socio-economic context of the future development of various background processes. In an illustrative case study, the climate change scores and nitrogen dioxide scores per seat kilometre for six technology options of regional rail transport are compared. Similar scores are calculated for a future bus alternative and an average Swiss car. The scenarios are deliberately chosen to maximise diversity. That is, they represent the entire range of future possible developments. Reference data and the unit process structure are taken from the Swiss LCA database 'ecoinvent 2000'. The results reveal that rail transport remains the best option for future regional transport in Switzerland. In all four assessed scenarios, four technology options of future rail transport perform considerably better than regional bus transport and car transport. Conclusions and Recommendations. The case study demonstrates the general feasibility of the developed approach for attributional prospective LCA. It allows for a focussed and in-depth analysis of the future development of each single unit process, while still accounting for the requirements of the final scenario integration. Due to its high transparency, the procedure supports the validation of LCI results. Furthermore, it is well-suited for incorporation into participatory methods so as to increase their credibility. Outlook and Future Work. Thus far, the proposed approach is only applied on a vehicle level not taking into account alterations in demand and use of different transport modes. Future projects will enhance the approach by tackling uncertainties in technology assessment of future transport systems. For instance, environmental interventions involving future maglev technology will be assessed so as to account for induced traffic generated by the introduction of a new transport system.     

Status of life cycle assessment and engineering research in South Africa

In view of the upcoming 2002 World Summit in Johannesburg, sustainable development is a topic of high priority in South Africa. Although the South African competency in Life Cycle Assessment (LCA) and Life Cycle Engineering (LCE) has grown to some extent over the last ten years, South African industry and government have been slow to realise the benefit of LCAs and LCE as tools to support cleaner production and sustainable development. However, the local application of these tools, as well as considerations during their use, differs from practices in developed countries. The applications of LCAs and LCE, the type of organisations involved and the limitations and common problems associated with these tools in South Africa are discussed.