Showing papers in "International Journal of Life Cycle Assessment in 2012"

Environmental impacts of hybrid and electric vehicles—a review

Abstract: Purpose A literature review is undertaken to understand how well existing studies of the environmental impacts of hybrid and electric vehicles (EV) address the full life cycle of these technologies. Results of studies are synthesized to compare the global warming potential (GWP) of different EV and internal combustion engine vehicle (ICEV) options. Other impacts are compared; however, data availability limits the extent to which this could be accomplished.

Lights and shadows in consequential LCA

Abstract: Consequential LCA (CLCA) is becoming widely used in the scientific community as a modelling technique which describes the consequences of a decision. However, despite the increasing number of case studies published, a proper systematization of the approach has not yet been achieved. This paper investigates the methodological implications of CLCA and the extent to which the applications are in line with the theoretical dictates. Moreover, the predictive and explorative nature of CLCA is discussed, highlighting the role of scenario modelling in further structuring the methodology. An extensive literature review was performed, involving around 60 articles published over a period of approximately 18 years, and addressing both methodological issues and applications. The information was elaborated according to two main aspects: what for (questions and modes of LCA) and what (methodological implications of CLCA), with focus on the nature of modelling and on the identification of the affected processes. The analysis points out that since the modelling principles of attributional LCA (ALCA) and CLCA are the same, what distinguishes the two modes of LCA is the choice of the processes to be included in the system (i.e. in CLCA, those that are affected by the market dynamics). However, the identification of those processes is often done inconsistently, using different arguments, which leads to different results. We suggest the use of scenario modelling as a way to support CLCA in providing a scientifically sound basis to model specific product-related futures with respect to technology development, market shift, and other variables. The CLCA is a sophisticated modelling technique that provides a way to assess the environmental consequences of an action/decision by including market mechanisms into the analysis. There is still room for improvements of the method and for further research, especially in relation to the following aspects: clarifying when and which market information is important and necessary; understanding the role of scenario modelling within CLCA; and developing a procedure to support the framing of questions to better link questions to models. Moreover, we suggest that the logic of mechanisms could be the reading guide for overcoming the dispute between ALCA and CLCA. Going further, this logic could also be extended, considering CLCA as an approach—rather than as a modelling principle with defined rules—to deepen LCA, providing the conceptual basis for including more mechanisms than just the market ones.

Methodology for systematic analysis and improvement of manufacturing unit process life cycle inventory (UPLCI) CO2PE! initiative (cooperative effort on process emissions in manufacturing). Part 2: case studies

Abstract: This report proposes a life-cycle analysis (LCA)-oriented methodology for systematic inventory analysis of the use phase of manufacturing unit processes providing unit process datasets to be used in life-cycle inventory (LCI) databases and libraries. The methodology has been developed in the framework of the CO2PE! collaborative research programme (CO2PE! 2011a) and comprises two approaches with different levels of detail, respectively referred to as the screening approach and the in-depth approach. The screening approach relies on representative, publicly available data and engineering calculations for energy use, material loss, and identification of variables for improvement, while the in-depth approach is subdivided into four modules, including a time study, a power consumption study, a consumables study and an emissions study, in which all relevant process in- and outputs are measured and analysed in detail. The screening approach provides the first insight in the unit process and results in a set of approximate LCI data, which also serve to guide the more detailed and complete in-depth approach leading to more accurate LCI data as well as the identification of potential for energy and resource efficiency improvements of the manufacturing unit process. To ensure optimal reproducibility and applicability, documentation guidelines for data and metadata are included in both approaches. Guidance on definition of functional unit and reference flow as well as on determination of system boundaries specifies the generic goal and scope definition requirements according to ISO 14040 (2006) and ISO 14044 (2006). The proposed methodology aims at ensuring solid foundations for the provision of high-quality LCI data for the use phase of manufacturing unit processes. Envisaged usage encompasses the provision of high-quality data for LCA studies of products using these unit process datasets for the manufacturing processes, as well as the in-depth analysis of individual manufacturing unit processes. In addition, the accruing availability of data for a range of similar machines (same process, different suppliers and machine capacities) will allow the establishment of parametric emission and resource use estimation models for a more streamlined LCA of products including reliable manufacturing process data. Both approaches have already provided useful results in some initial case studies (Kellens et al. 2009; Duflou et al. (Int J Sustain Manufacturing 2:80–98, 2010); Santos et al. (J Clean Prod 19:356–364, 2011); UPLCI 2011; Kellens et al. 2011a) and the use will be illustrated by two case studies in Part 2 of this paper (Kellens et al. 2011b).

Life cycle assessment (LCA) applied to the process industry: a review

Abstract: Life cycle assessment (LCA) methodology is a well-established analytical method to quantify environmental impacts, which has been mainly applied to products. However, recent literature would suggest that it has also the potential as an analysis and design tool for processes, and stresses that one of the biggest challenges of this decade in the field of process systems engineering (PSE) is the development of tools for environmental considerations. This article attempts to give an overview of the integration of LCA methodology in the context of industrial ecology, and focuses on the use of this methodology for environmental considerations concerning process design and optimization. The review identifies that LCA is often used as a multi-objective optimization of processes: practitioners use LCA to obtain the inventory and inject the results into the optimization model. It also shows that most of the LCA studies undertaken on process analysis consider the unit processes as black boxes and build the inventory analysis on fixed operating conditions. The article highlights the interest to better assimilate PSE tools with LCA methodology, in order to produce a more detailed analysis. This will allow optimizing the influence of process operating conditions on environmental impacts and including detailed environmental results into process industry.

Life cycle assessment of aquaculture systems-a review of methodologies.

Abstract: Purpose As capture fishery production has reached its limits and global demand for aquatic products is still increasing, aquaculture has become the world’s fastest growing animal production sector. In attempts to evaluate the environmental consequences of this rapid expansion, life cycle assessment (LCA) has become a frequently used method. The present review of current peer-reviewed literature focusing on LCA of aquaculture systems is intended to clarify the methodological choices made, identify possible data gaps, and provide recommendations for future development within this field of research. The results of this review will also serve as a start-up activity of the EU FP7 SEAT (Sustaining Ethical Aquaculture Trade) project, which aims to perform several LCA studies on aquaculture systems in Asia over the next few years.

Impact of lifetime on US residential building LCA results

Abstract: Many life cycle assessment (LCA) studies do not adequately address the actual lifetime of buildings and building products, but rather assume a typical value. The goal of this study was to determine the impact of lifetime on residential building LCA results. Including accurate lifetime data into LCA allows a better understanding of a product’s environmental impact that would ultimately enhance the accuracy of LCA results. This study focuses on refining the US residential building lifetime, as well as lifetime of interior renovation products that are commonly used as interior finishes in homes, to improve LCA results. Residential building lifetime data that presents existing trends in the USA was analyzed as part of the study. Existing product life cycle inventory data were synthesized to form statistical distributions that were used instead of deterministic values. Product elementary flows were used to calculate life cycle impacts of a residential model that was based on median US residential home size. Results were compared to existing residential building LCA literature to determine the impact of using updated, statistical lifetime data. A Monte Carlo analysis was performed for uncertainty analysis. Sensitivity analysis results were used to identify hotspots within the LCA results. Statistical analysis of US residential building lifetime data indicate that average building lifetime is 61 years and has a linearly increasing trend. Interior renovation energy consumption of the residential model that was developed by using average US conditions was found to have a mean of 220 GJ over the life cycle of the model. Ratio of interior renovation energy consumption to pre-use energy consumption, which includes embodied energy of materials, construction activities, and associated transportation was calculated to have a mean of 34% for regular homes and 22% for low-energy homes. Ratio of interior renovation to life cycle energy consumption of residential buildings was calculated to have a mean of 3.9% for regular homes and 7.6% for low-energy homes. Choosing an arbitrary lifetime for buildings and interior finishes, or excluding interior renovation impacts introduces a noteworthy amount of error into residential building LCA, especially as the relative importance of materials use increases due to growing number of low-energy buildings that have lower-use phase impacts.

Life cycle energy consumption and CO2 emission of an office building in China

Abstract: Building is one of the main factors of energy use and greenhouse gas emissions. Reducing energy consumption and carbon dioxide (CO2) emission from building is urgent for environmental protection and sustainable development. The objective of this study is to develop a life cycle assessment (LCA) model for an office building in China to assess its energy consumption and CO2 emission, determine the whole life cycle phases, and the significant environmental aspects that contribute most to the impact. A process-based LCA has been used to identify and quantify the energy consumption and CO2 emission of the office building. The LCA is conducted in accordance with the Environmental Protection Agency, The Society of Environmental Toxicology and Chemistry, and the International Organization for Standardization standards for life cycle assessments. The entire life cycle including building materials production, construction, operation, and demolition of the building is studied. A service life of 50 years is assumed and the major construction materials such as concrete, cement, brick, steel, timber, glass, and plastic are selected for the building. The results show that building operation uses the largest share of energy and contributes most to CO2 emission. The cooling and heating system in building operation strongly influence the energy consumption and CO2 emission of the building. In addition, the large quantity use of concrete and steel in materials production, and the treatment of end-of-life building materials are also the important aspects impacting the environmental performance of the building. Based on the results of the study, some environmental improvements aiming at reducing energy consumption and CO2 emission throughout the life cycle of the building are provided. This study provides an LCA of the energy consumption and CO2 emission of a typical office building in China. It determines the whole life cycle phases that contribute most to the impact and defines the significant environmental aspects of the building. This study also shows the importance of using a life cycle perspective when evaluating energy consumption and CO2 emission of building and also lays the groundwork for LCA studying of other office buildings in China.

Time-adjusted global warming potentials for LCA and carbon footprints

Abstract: Purpose The common practice of summing greenhouse gas (GHG) emissions and applying global warming potentials (GWPs) to calculate CO2 equivalents misrepresents the global warming effects of emissions that occur over a product or system’s life cycle at a particular time in the future. The two primary purposes of this work are to develop an approach to correct for this distortion that can (1) be feasibly implemented by life cycle assessment and carbon footprint practitioners and (2) results in units of CO2 equivalent. Units of CO2 equilavent allow for easy integration in current reporting and policy frameworks.

LCA of a tomato crop in a multi-tunnel greenhouse in Almeria

Abstract: Purpose Protected crops have expanded significantly in the Mediterranean area over the last few decades as a successful means to provide abundant and high-quality produce. Although resources are generally used efficiently, greenhouse areas cause major environmental impacts. The aim of this work was to study, from an environmental point of view, the improvement capacity of greenhouse areas in the Mediterranean region and to assess several alternative agricultural practices to decrease their contribution to the environmental impacts in this system.

Towards life cycle sustainability assessment: an implementation to photovoltaic modules

Abstract: The main goal of the paper is to carry out the first implementation of sustainability assessment of the assembly step of photovoltaic (PV) modules production by Life Cycle Sustainability Assessment (LCSA) and the development of the Life Cycle Sustainability Dashboard (LCSD), in order to compare LCSA results of different PV modules. The applicability and practicability of the LCSD is reported thanks to a case study. The results show that LCSA can be considered a valuable tool to support decision-making processes that involve different stakeholders with different knowledge and background. The sustainability performance of the production step of Italian and German polycrystalline silicon modules is assessed using the LCSD. The LCSD is an application oriented to the presentation of an LCSA study. LCSA comprises life cycle assessment (LCA), life cycle costing and social LCA (S-LCA). The primary data collected for the German module are related to two different years, and this led to the evaluation of three different scenarios: a German 2008 module, a German 2009 module, and an Italian 2008 module. According to the LCA results based on Ecoindicator 99, the German module for example has lower values of land use [1.77 potential disappeared fractions (PDF) m2/year] and acidification (3.61 PDF m2/year) than the Italian one (land use 1.99 PDF m2/year, acidification 3.83 PDF m2/year). However, the German module has higher global warming potential [4.5E–05 disability-adjusted life years (DALY)] than the Italian one [3.00E−05 DALY]. The economic costs of the German module are lower than the Italian one, e.g. the cost of electricity per FU for the German module is 0.12 €/m2 compared to the Italian 0.85 €/m2. The S-LCA results show significant differences between German module 2008 and 2009 that represent respectively the best and the worst overall social performances of the three considered scenarios compared by LCSD. The aggregate LCSD results show that the German module 2008 has the best overall sustainability performance and a score of 665 points out of 1,000 (and a colour scale of light green). The Italian module 2008 has the worst overall sustainability performance with a score of 404 points, while the German module 2009 is in the middle with 524 points. The LCSA and LCSD methodologies represent an applicable framework as a tool for supporting decision-making processes which consider sustainable production and consumption. However, there are still challenges for a meaningful application, particularly the questions of the selection of social LCA indicators and how to weigh sets for the LCSD.

Assessment of the environmental performance of buildings: A critical evaluation of the influence of technical building equipment on residential buildings

Abstract: Sustainability assessments of buildings using the life cycle approach have become more and more common. This includes the assessment of the environmental performance of buildings. However, the influence of the construction products used for the fabric, the finishing, and the technical building equipment of buildings has hardly been described in literature. For this reason, we evaluated the influence of the technical building equipment and its impact on the environment for different residential buildings. Five residential buildings were evaluated by applying the methodology of life cycle assessment (LCA) (ISO14040) expressed using quantitative assessment categories according to prEN15978. Results show that the optimization of energy performance has already reached a high level in Austria, so that the overall potential for possible improvements is quite low. Especially in low-energy and passive–house-standard residential buildings, the limits for energy optimization in the use phase have mostly been achieved. In contrast to this, the integrated LCA (iLCA) findings attribute a high optimization potential to the construction products used for the technical building equipment as well as to the building fabric and finishing. Additionally, the passive house shows the lowest contribution of the technical building equipment on the overall LCA results. The iLCA findings suggest that it is recommended to include the technical building equipment for future assessments of the environmental performance of buildings. It is also suggested to use a broad number of environmental indicators for building LCA.

PestLCI 2.0: a second generation model for estimating emissions of pesticides from arable land in LCA

Abstract: The spatial dependency of pesticide emissions to air, surface water and groundwater is illustrated and quantified using PestLCI 2.0, an updated and expanded version of PestLCI 1.0. PestLCI is a model capable of estimating pesticide emissions to air, surface water and groundwater for use in life cycle inventory (LCI) modelling of field applications. After calculating the primary distribution of pesticides between crop and soil, specific modules calculate the pesticide’s fate, thus determining the pesticide emission pattern for the application. PestLCI 2.0 was developed to overcome the limitations of the first model version, replacement of fate calculation equations and introducing new modules for macropore flow and effects of tillage. The accompanying pesticide database was expanded, the meteorological and soil databases were extended to include a range of European climatic zones and soil profiles. Environmental emissions calculated by PestLCI 2.0 were compared to results from the risk assessment models SWASH (surface water emissions), FOCUSPEARL (groundwater via matrix leaching) and MACRO (groundwater including macropore flow, only one scenario available) to partially validate the updated model. A case study was carried out to demonstrate the spatial variation of pesticide emission patterns due to dependency on meteorological and soil conditions. Compared to PestLCI 1.0, PestLCI 2.0 calculated lower emissions to surface water and higher emissions to groundwater. Both changes were expected due to new pesticide fate calculation approaches and the inclusion of macropore flow. Differences between the SWASH and FOCUSPEARL and PestLCI 2.0 emission estimates were generally lower than 2 orders of magnitude, with PestLCI generally calculating lower emissions. This is attributed to the LCA approach to quantify average cases, contrasting with the worst-case risk assessment approach inherent to risk assessment. Compared to MACRO, the PestLCI 2.0 estimates for emissions to groundwater were higher, suggesting that PestLCI 2.0 estimates of fractions leached to groundwater may be slightly conservative as a consequence of the chosen macropore modelling approach. The case study showed that the distribution of pesticide emissions between environmental compartments strongly depends on local climate and soil characteristics. PestLCI 2.0 is partly validated in this paper. Judging from the validation data and case study, PestLCI 2.0 is a pesticide emission model in acceptable accordance with both state-of-the-art pesticide risk assessment models. The case study underlines that the common pesticide emission estimation practice in LCI may lead to misestimating the toxicity impacts of pesticide use in LCA.

Life cycle assessment of the supply and use of bioenergy: impact of regional factors on biogas production

Abstract: This article evaluates the parameters that influence the results of a life cycle assessment (LCA) of biogas production from maize and the conversion of biogas into electricity. The environmental impacts of biogas vary according to regional farming procedures and, therefore, the soil, climate conditions, crop yield, and cultivation management. This study focuses on these regional parameters and the existing infrastructure, including the number of installed biogas plants and their share of used heat. To assess the regional impact, the LCAs of maize cultivation, on the one hand, and the production and use of biogas, on the other, were performed for three different areas. These areas were the administrative districts of Celle, Hildesheim, and Goettingen; all located in the south of Lower Saxony, Germany. The areas differed in geographic location conditions, crop yield, and the number of installed biogas plants. The necessary data for modeling the cultivation of maize were derived from the specific regional and local parameters of each area. The most important parameters were the soil characteristics and the climate conditions for cultivating maize. The share of used heat from combined heat and power unit (CHP) was another relevant factor for biogas production and use. Our results demonstrate significant differences among the investigated areas. The smallest environmental impact of all the considered categories occurs in Goettingen and the largest in Celle. The net greenhouse gas emissions vary from 0.179 kg CO2 eq./kWhel in Celle to 0.058 kg CO2 eq./kWhel in Goettingen. This result is due to the maize cultivation system and the different credits for using heat from the CHP. Variances in energy crop cultivation result from different nitrogen and irrigation demands. In addition, despite higher applications of nitrogen fertilizer and irrigation, the maize yield is lower in Celle. The impact category of total fossil energy shows similar results to that of the greenhouse gas (GHG) emissions. The results range from −0.274 to 0.175 kWh/kWhel. The results of acidification and eutrophication vary from 1.62 in Goettingen to 1.94 g SO2 eq./kWhel in Celle and respectively 0.330 to 0.397 g PO 4 3− eq./kWhel. These differences are primarily caused by maize cultivation, especially irrigation. Cultivating maize and using waste heat from the CHP were identified as the most influential parameters for the GHG emissions and total fossil energy demand. Regarding acidification and eutrophication, the most relevant factors are the application of digester output and the emissions from the CHP. Our results show the need to consider regional parameters in the LCA of bioenergies, particularly biogas production and use, especially if the LCA studies are used for generalized evaluations such as statements on the climate protection potential of biogas.

Environmental analysis of rainwater harvesting infrastructures in diffuse and compact urban models of Mediterranean climate

Abstract: At present, many urban areas in Mediterranean climates are coping with water scarcity, facing a growing water demand and a limited conventional water supply. Urban design and planning has so far largely neglected the benefits of rainwater harvesting (RWH) in the context of a sustainable management of this resource. Therefore, the purpose of this study was to identify the most environmentally friendly strategy for rainwater utilization in Mediterranean urban environments of different densities. The RWH systems modeled integrate the necessary infrastructures for harvesting and using rainwater in newly constructed residential areas. Eight scenarios were defined in terms of diffuse (D) and compact (C) urban models and the tank locations ((1) underground tank, (2) below-roof tank, (3) distributed-over-roof tank, and (4) block tank). The structural and hydraulic sizing of the catchment, storage, and distribution subsystems was taken into account using an average Mediterranean rainfall, the area of the harvesting surfaces, and a constant water demand for laundry. The quantification of environmental impacts was performed through a life cycle assessment, using CML 2001 Baseline method. The necessary materials and processes were considered in each scenario according to the lifecycle stages (i.e., materials, construction, transportation, use, and deconstruction) and subsystems. The environmental characterization indicated that the best scenario in both urban models is the distributed-over-roof tank (D3, C3), which provided a reduction in impacts compared to the worst scenario of up to 73% in diffuse models and even higher in compact ones, 92% in the most dramatic case. The lower impacts are related to the better distribution of tank weight on the building, reducing the reinforcement requirements, and enabling energy savings. The storage subsystem and the materials stage contributed most significantly to the impacts in both urban models. In the compact density model, the underground-tank scenario (C1) presented the largest impacts in most categories due to its higher energy consumption. Additionally, more favorable environmental results were observed in compact densities than in diffuse ones for the Global Warming Potential category along with higher water efficiencies. The implementation of one particular RWH scenario over another is not irrelevant in drought-stress environments. Selecting the most favorable scenario in the development of newly constructed residential areas provides significant savings in CO2 emissions in comparison with retrofit strategies. Therefore, urban planning should consider the design of RWH infrastructures using environmental criteria in addition to economic, social, and technological factors, adjusting the design to the potential uses for which the rainwater is intended. Additional research is needed to quantify the energy savings associated with the insulation caused by using the tank distributed over the roof. The integration of the economic and social aspects of these infrastructures in the analysis, from a life cycle approach, is necessary for targeting the planning and design of more sustainable cities in an integrated way.

Life cycle assessment at nanoscale: review and recommendations

Abstract: Purpose The need for a systematic evaluation of the human and environmental impacts of engineered nanomaterials (ENMs) has been widely recognized, and a growing body of literature is available endorsing life cycle assessment (LCA) as a valid tool for the same. The purpose of this study is to evaluate how the nano-specific environmental assessments are being done within the existing framework of life cycle inventory and impact assessment and whether these frameworks are valid and/or whether they can be modified for nano-evaluations.

Spatially explicit fate factors of phosphorous emissions to freshwater at the global scale

Abstract: Purpose The location of a phosphorus emission can strongly affect its expected fate in freshwater. To date, in Life Cycle Assessment (LCA), fate factors for phosphorus emissions have been derived for continents or large countries and had limited spatial resolution. These fate factors do not account sufficiently for local variations and are not applicable globally. In this paper, fate factors for freshwater eutrophication are derived for phosphorus emissions to freshwater on a global scale with a half-degree resolution.

Water footprint of livestock: comparison of six geographically defined beef production systems

Abstract: Purpose Water use in the livestock sector has featured in the debate about sustainable food systems. Most evidence has come from virtual water calculations which lack impact assessment and adequate consideration of the heterogeneity in livestock production. This study sought new evidence, using a recently developed life cycle impact assessment method for water use to assess six geographically defined beef cattle production systems in New South Wales, Australia, a major production region.

Life cycle assessment of construction and demolition waste management systems: a Spanish case study

Abstract: Purpose The aim of this study is to develop and analyse a life cycle inventory of construction and demolition waste (C&DW) management systems based on primary data collected directly from Spanish enterprises involved in the life cycle of this type of waste material. Special emphasis is placed on assessing the environmental profile of inert waste sorting and treatment (IWST) facilities.

A review of life cycle assessments on wind energy systems

Abstract: Purpose Several life cycle assessments (LCAs) of wind energy published in recent years are reviewed to identify methodological differences and underlying assumptions.

Multi-attribute life cycle assessment of preventive maintenance treatments on road pavements for achieving environmental sustainability

Abstract: Although a significant number of environmental protection measures concerning industrial products and processes have emerged over the past few years, similar measures have only started to appear in road construction and related practices. There is a need for understanding what a “sustainable pavement” would entail in terms of greenhouse gas emissions and energy consumption. Since environmental impact assessment of major projects is becoming mandatory in many countries, various research projects attempt to evaluate the environmental impact of different pavement materials, technologies, or processes over the road life cycle. To support these efforts, there is a need to measure and describe different aspects of sustainability related to road pavements. In particular, keeping road pavements at high service levels through a preventive maintenance approach during the pavement service life has been proven to provide significant improvement of their performance and reduce their deterioration rate. This paper describes an innovative methodology to evaluate the environmental impact of preventive maintenance activities. It relates these activities to performance and cost during the service life of the pavement through a multi-attribute “life cycle cost, performance, and environmental analysis”. Emissions and energy saved adopting several preventive maintenance strategies were computed, relating them to cost and performance. Equipment and materials usually involved in road maintenance practices were also analyzed in order to assess specific fuel consumption and energy spent. An ad hoc index was ultimately created, adopting a script file to evaluate the best strategy through the multi-attribute approach. Results show how eco-effective it can be to improve pavement management practices on roads by implementing energy efficient treatments and strategies. Furthermore, eco-saving factors could represent a new and innovative feature to be added in the sustainability assessment process for pavements to evaluate different alternatives and assist authorities choosing between different investment solutions as a part of a decision support system.

Differences between LCA for analysis and LCA for policy: A case study on the consequences of allocation choices in bio-energy policies

Abstract: Purpose - The increasing concern for adverse effects of climate change has spurred the search for alternatives for conventional energy sources Life cycle assessment (LCA) has increasingly been used to assess the potential of these alternatives to reduce greenhouse gas emissions The popularity of LCA in the policy context puts its methodological issues into another perspective This paper discusses how bio-electricity directives deal with the issue of allocation and shows its repercussions in the policy field Methods - Multifunctionality has been a well-known problem since the early development of LCA and several methods have been suggested to deal with multifunctional processes This paper starts with a discussion of the most common allocation methods This discussion is followed by a description of bio-energy policy directives The description shows the increasing importance of LCA in the policy context as well as the lack of consensus in the application of allocation methods Methodological differences between bio-energy directives possibly lead to different assessments of bio-energy chains To assess the differences due to methodological choices in bio-energy directives, this paper applies three different allocation methods to the same bioelectricity generation system The differences in outcomes indicate the importance of solving the allocation issue for policy decision making Results and discussion - The case study focuses on bioelectricity from rapeseed oil To assess the influence of the choice of allocation in a policy directive, three allocation methods are applied: economic partitioning (on the basis of proceeds), physical partitioning (on the basis of energy content), and substitution (under two scenarios) The outcomes show that the climate change score is assessed quite differently; ranging from 0293 kg to 0604 kg CO2 eq/kWh It is argued that this uncertainty hampers the optimal use of LCA in the policy context The aim of policy LCAs is different from the aim of LCAs for analysis Therefore, it is argued that LCAs in the policy context will benefit from a new guideline based on robustness Conclusions - The case study confirms that the choice of allocation method in policy directives has large influence on the outcomes of an LCA With the growing popularity of LCA in policy directives, this paper recommends a new guideline for policy LCAs The high priority of robustness in the policy context makes it an ideal starting point of this guideline An accompanying dialog between practitioners and commissioners should further strengthen the use of LCA in policy directives

A PCA-based method for construction of composite sustainability indicators

Abstract: Purpose Sustainable manufacturing is practiced globally as a comprehensive strategy for improving the sustainability performance of the manufacturing industry. While sustainability is characterized into such three dimensions as economic, environmental, and social, currently, there is no quantitative method yet to measure the so-called “sustainability” in the manufacturing industry. The objective of this research is to develop a comprehensive and effective quantitative method to measure the overall sustainability performance of manufacturing companies.

On the link between economic and environmental performance of Swiss dairy farms of the alpine area

Abstract: Promoting the economic and environmental performance of Swiss farms is a major objective of Swiss agricultural policy. In the present paper, we investigate the relationship between the economic and global environmental performance of the Swiss dairy farms in the alpine area. The analysis relies on a sample of 56 dairy farms from the Farm Accountancy Data Network, for which highly precise and comprehensive Life Cycle Assessments have been carried out. The work income per family work unit is used as indicator of the economic performance of a farm. The so-called global environmental performance of a farm is, for its part, measured by means of an eco-efficiency indicator for each environmental impact considered (demand for non-renewable energy resources, eutrophication potential, aquatic ecotoxicity potential, human toxicity potential and land use) and of an aggregate eco-efficiency indicator assessed using a Data Envelopment Analysis-based approach. The relationship between economic and global environmental performance is assessed by means of non-parametric Spearman’s rank correlation analysis. The results of the analysis reveal the existence of a positive relationship between economic and global environmental performance. This positive relationship exists for all environmental issues considered and thus also for the aggregate eco-efficiency indicator. Its strength, however, substantially varies from one issue to another. This study provides the evidence that there is no trade-off between economic and global environmental farm performance. When they improve their economic performance, farms also tend to improve their global environmental performance and vice versa. This finding is of central relevance for policy-makers as it should contribute to improving the acceptance among farmers of the environmental objectives of Swiss agricultural policy in terms of an increase in environmental resource use productivity. In this sense this work provides valuable insights into the sustainable performance of the Swiss dairy sector in the alpine area.

The critical review of life cycle assessment studies according to ISO 14040 and 14044

Abstract: The revision of the ISO LCA (life cycle assessment) standards in October 2006 brought some changes of the critical review process compared to the older series ISO 14040–43 (1997, 1998, 2000a, b). Furthermore, the importance of LCA has grown rapidly in recent years, but this growth was not accompanied by a corresponding increase of knowledge about the voluntary and obligatory review processes. It is the intention of this paper to analyse the relevant standards and to present some personal experiences in conducting critical reviews. A peer review for LCA studies was first proposed in the Society of Environmental Toxicology and Chemistry (SETAC) guidelines “A Code of Practice” (1993). The ISO standard 14040 (1997) took up this proposition and described three types of “Critical review” which are optional in general, but mandatory “for LCA studies used to make a comparative assertion that is disclosed to the public”. This strong prescription was reinforced in the revised standards ISO 14040 and 14044 (2006a, b) and even stricter, unambiguous formulations were added to the text. In addition, the minimum number of experts in a “review by interested parties” is now three (including the chair). Large panels with more than four experts are rare, but do occur occasionally. Out of personal experience, I strongly support the interactive (accompanying) mode of conducting the critical review process (ISO also allows the “a posteriori” mode). I also suggest the removal of some inconsistencies during the next update of the standards. No major changes are recommended, however, since ISO 14040 + 14044 has become the reference standard for several other international standards based on the life cycle concept.

A system dynamics approach in LCA to account for temporal effects—a consequential energy LCI of car body-in-whites

Abstract: Purpose The purpose of this paper is to take steps towards a life cycle assessment that is able to account for changes over time in resource flows and environmental impacts. The majority of life cycle inventory (LCI) studies assume that computation parameters are constants or fixed functions of time. This assumption limits the opportunities to account for temporal effects because it precludes consideration of the dynamics of the product system.

Land use indicators in life cycle assessment

Abstract: Purpose Inclusion of land use-related environmental aspects into LCA methodology has been under active development in recent years Although many indicators have been developed and proposed for different aspects of land use (climate change, biodiversity, resource depletion and soil quality), many of indicators have, as yet, not been tested and compared in LCA applications The aim of this study is to test the different LCIA indicators in practice in a case study of beer production

An input–output based framework to evaluate human labour in life cycle assessment

Abstract: Purpose In LCA, the intrinsic dependence of productions to human labour (HL) activities is usually neglected, without providing any clear arguments. HL is not considered to be related to and affected by, changes to the functional unit, although this is evidently not the case. This research aims at investigating the relationship between HL and LCA and at developing an operational framework to assess the life cycle environmental impact of HL in LCA.

Regional carbon footprint analysis of dairy feeds for milk production in the USA

Abstract: Purpose A greenhouse gas emissions analysis (carbon footprint) was conducted for cultivation, harvesting, and production of common dairy feeds used for the production of dairy milk in the USA. The goal was to determine the carbon footprint (grams CO2 equivalents (gCO2e)/kg of dry feed) in the USA on a regional basis, identify key inputs, and make recommendations for emissions reduction.

Life cycle assessment of energy and GHG emissions during ethanol production from grass straws using various pretreatment processes

Abstract: Purpose The aim of this study was to perform a well-to-pump life cycle assessment (LCA) to investigate the overall net energy balance and environmental impact of bioethanol production using Tall Fescue grass straw as feedstock. The energy requirements and greenhouse gas (GHG) emissions were compared to those of gasoline to explore the potential of bioethanol as sustainable fuel.