ALBERT

Description: Purpose The goal of this study is to analyze the environmental improvement brought about by an alternative system for waste management proposed by the Integral-b project, funded by the European Union (EU). Its aim is to treat both used cooking oil (UCO) and organic waste from the restaurant and catering sector in Spain, by biodiesel production and anaerobic digestion, respectively. A cogeneration engine adapted to use glycerin as a fuel is implemented. Methods The functional unit (FU) is the management of the UCO and organic waste from restaurants and catering produced per person and year in Spain. The system proposed (scenario A) is compared to a system consisting of the prevailing management options for the same kind of waste (scenario B). Apart from including biodiesel production from the UCO, this reference scenario assumes that the organic waste is allocated to different streams, according to Spanish statistics. The systems under study generate different coproducts and as such are complex; therefore, system expansion is performed. Different scenario formulations are set to analyze the influence of assumptions regarding coproduct credits in the results. Finally, Monte Carlo simulations are carried out to analyze parameter uncertainty. Results and discussion The environmental benefits caused by scenario A are conditional on the choices regarding coproduct credits. Scenario A causes a reduction of the impact (43–655 %) in most of the scenario formulations when the current levels of UCO collection are considered. However, when higher levels of UCO collection are taken into account for the definition of the FU, scenario B performs better for half of the scenario formulations, due to the increase in the environmental credits from glycerin production. The only impact categories for which scenario A performs unconditionally better than scenario B are global warming and photochemical ozone creation. Parameter uncertainty appears to influence the comparative results to a lesser extent, mainly caused by the parameters involved in avoided processes. Conclusions Although system expansion appears as an option for dealing with the multifunctionality of waste management processes, uncertainty caused by choices must be assessed. Under our scenario assumptions, re-using the glycerol in the system proposed by Integral-b can be detrimental, and the reference scenario results in higher avoided burdens in some scenario formulations. Including glycerin valorization in scenario B should be considered if the biodiesel production keeps increasing in Spain. Analyzing parameter uncertainty helps to provide reliable results.

Description: Purpose Phase change materials (PCMs) hold considerable promise for thermal energy storage and reduction of temperature swings in building space, and can reduce reliance on fossil fuel sources for both heating and cooling. Previous studies have evaluated the use of PCMs for energy storage and provided some limited information on the embodied energy of the PCM; however, an important factor that has not fully been addressed until now is the environmental impact of preparation of organic PCMs. This study presents life cycle assessments (LCAs) of two organic, biosourced PCMs for their applications, focusing on embodied energy and CO 2 emissions. Methods Dodecanoic acid produced from palm kernel oil was considered as a PCM for use in a solar thermal water heating application, and ethyl hexadecanoate produced from algae was considered for thermal buffering. The functional units were defined as 1 t of dodecanoic acid PCM and 1 kg of encapsulated ethyl hexadecanoate PCM, respectively. The LCA encompasses all phases in the PCM production: growth and harvesting of the feedstocks, extraction of the oil, treatment of the oil, and separation of singular components. The two PCMs were evaluated in terms of the payback times for their embodied energies and embodied CO 2 under a modeled use phase. Results and discussion The energy payback time for dodecanoic acid in a solar thermal application was found to be less than 2 years. Although production of dodecanoic acid is a net CO 2 emitter, use of this PCM in a solar thermal system can recoup the CO 2 of production in less than a year. Ethyl hexadecanoate produced from algae, considered for use in a thermal buffering wallboard product, would require at least 30 years of use before its energy savings would match its embodied energy, mostly due to the drying step in the production of the PCM. However, ethyl hexadecanoate is a strong sequester of CO 2 at 7.6 t per ton of ethyl hexadecanoate. Conclusions Dodecanoic acid produced from palm kernel oil for use in a solar thermal hot water system appears to be a viable PCM. Its payback time, both for energy and carbon emissions, is under 3 years. On the other hand, the high embodied energy of ethyl hexadecanoate produced from algae gives a prohibitively long payback time for use in domestic thermal buffering applications.

Description: Purpose Current comparative life cycle assessment (LCA) studies claim to answer whether it is better or worse for the environment to change from old to new systems. Most commonly, the attributional LCA (ALCA) is practised despite its limitations to describe market effects. Hence, an attempt is done here to include market effects in the ALCA practice for comparisons in order to improve ALCA. The purpose is neither to investigate which LCA concept, ALCA, consequential LCA or decisional LCA, is the best for comparisons nor which is the best for decision-making. Methods Here, for the first time, a method based on marked changes which can be used for sensitivity checks of comparative ALCAs, advanced ALCA (AALCA) is presented. The new concept of global change mix factors (GCMF) is introduced. The method, based on accessible market data, is applied to previous comparative ALCAs of conductive adhesives, cooling modules used in radio base stations, office computing systems, as well as personal devices usage, here represented by multifunctional smartphones replacing other devices such as digital cameras. Results and discussion The results show that AALCA based on market data improves the understanding and can act as a sensitivity check of comparative ALCA results. For declining markets of products, with relatively high eco-environmental impacts, the difference between comparative AALCA and ALCA can be significant. As AALCA is founded in marginal electricity thinking and uses market data, there are similarities between AALCA and simplistic consequential LCA (CLCA). However, AALCA is not intended to replace CLCA or decisional LCA (DLCA). Conclusions By applying allocation factors, GCMF, based on real or future market changes, the interdependence of global markets and micro-level LCA shifts can be taken into account in comparative micro-level ALCA studies and make them more robust. Further, the sensitivity of using price units instead of physical units, as the basis for the GCMF, should be investigated. The degree to which AALCA and CLCA can complement each other should be examined. Also, the degree to which the GCMF used in AALCA-H address rebound effects should be further explored. The annual eco-environmental impacts of mobile devices towards 2020 are also of interest, and more LCA case studies are welcome.

Description: Purpose Previous estimates of carbon payback time (CPT) of corn ethanol expansion assumed that marginal yields of newly converted lands are the same as the average corn yield, whereas reported marginal yields are generally lower than the average yield (47–83 % of average yield). Furthermore, these estimates assumed that the productivity of corn ethanol system and climate change impacts per unit greenhouse gas (GHG) emissions remain the same over decades to a century. The objective of this study is to re-examine CPT of corn ethanol expansion considering three aspects: (1) yields of newly converted lands (i.e., marginal yield), (2) technology improvements over time within the corn ethanol system, and (3) temporal sensitivity of climate change impacts. Methods A new approach to CPT calculation is proposed, where changes in productivity of ethanol conversion process and corn yield are taken into account. The approach also allows the use of dynamic characterization approach to GHGs emitted in different times, as an option. Data are collected to derive historical trends of bioethanol conversion efficiency and corn yield, which inform the development of the scenarios for future biofuel conversion efficiency and corn yield. Corn ethanol’s CPTs are estimated and compared for various marginal-to-average (MtA) yield ratios with and without considering technology improvements and time-dependent climate change impacts. Results and discussion The results show that CPT estimates are highly sensitive to both MtA yield ratio and productivity of ethanol system. Without technological advances, our CPT estimates for corn ethanol from newly converted Conservation Reserve Program (CRP) land exceed 100 years for all MtA yield ratios tested except for the case where MtA yield ratio is 100 %. When the productivity improvements within corn ethanol systems since previous CPT estimates and their future projections are considered, our CPT estimates fall into the range of 15 years (100 % MtA yield ratio) to 56 years (50 % MtA yield ratio), assuming land conversion takes place in early 2000s. Incorporating diminishing sensitivity of GHG emissions to future emissions year by year, however, increases the CPT estimates by 57 to 13 % (from 17 years for 100 % MtA yield ratio to 88 years for 50 % MtA yield ratio). For 60 MtA yield ratio, CPT is estimated to be 43 years, which is relatively close to previous CPT estimates (i.e., 40 to 48 years) but with very different underlying reasons. Conclusions This study highlights the importance of considering technological advances in understanding the climate change implications of land conversion for corn ethanol. Without the productivity improvements in corn ethanol system, the prospect of paying off carbon debts from land conversion within 100 years becomes unlikely. Even with the ongoing productivity improvements, the yield of newly converted land can significantly affect the CPT. The results reinforce the importance of considering marginal technologies and technology change in prospective life cycle assessment.

Description: Purpose The security of the supply of resources is a key policy and business concern. This concern has been increasingly addressed by bodies such as the European Commission to help identify materials of potential concern in terms of economic importance and supply risks. Equally, tools such as life cycle assessment (LCA) systematically compile inventories of the resources attributable to the supply of goods and services. Such well-established tools, hence, provide an important opportunity for business and governments for strategic management and for identifying improvement options that reduce reliance on so-called critical raw materials (CRMs). This paper explores current practice and the potential of LCA to help business and governments more systematically assess their supply chains. Methods Raw materials of concern to business and governments in relation to security of supply are denoted as critical . This paper highlights how such CRMs are identified in the existing methodologies. It then focuses on LCA methodology and explores its potential in providing information on CRMs at different levels: considering the flows of CRMs at inventory level, including criticality criteria in the impact assessment, and analyzing the flows of CRMs associated with the consumption of goods and services at macroeconomic scale. Results and discussion Consideration of resource security can be specifically addressed in LCA starting from the goal and scope definition. These CRMs may otherwise be neglected due to cut-off criteria based, e.g., on quantity. If systematically addressed, LCA can provide such CRM information routinely at inventory level. Inclusion of further indicators under the Area of Protection (AoP) “Resources” in LCA may also ensure such assessments more systematically address issues such as criticality. In strategic analysis, as those at macroeconomic scale, LCA results at the inventory (e.g., amounts of CRMs domestically extracted and those used for producing imported and exported intermediate products) and at impact assessment level can better support decision making. Conclusions At both microscale and macroscale, LCA might have more potential in capturing hot spots and improvement opportunities of raw materials of concern, not only in terms of scarcity. This paper highlights that LCA is well positioned for providing information on resource-related issues of concern to business and governments such as the criticality of raw materials used in the supply chains. The paper outlines the methodological developments that could enhance LCA potential to further support resource assessments to help more systematically meet such business and governmental interests.

Description: Purpose USEtox is a scientific consensus model for assessing human toxicological and ecotoxicological impacts that is widely used in life cycle assessment (LCA) and other comparative assessments. However, how user requirements are met has never been investigated. To guide future model developments, we analyzed user expectations and experiences and compared them with the developers’ visions. Methods We applied qualitative and quantitative data collection methods including an online questionnaire, semi-structured user and developer interviews, and review of scientific literature. Questionnaire and interview results were analyzed in an actor-network perspective in order to understand user needs and to compare these with the developers’ visions. Requirement engineering methods, more specifically function tree, system context, and activity diagrams, were iteratively applied and structured to develop specific user requirements-driven recommendations for setting priorities in future USEtox development and for discussing general implications for developing scientific models. Results and discussion The vision behind USEtox was to harmonize available data and models for assessing toxicological impacts in LCA and to provide global guidance for practitioners. Model developers show different perceptions of some underlying aspects including model transparency and expected user expertise. Users from various sectors and geographic regions apply USEtox mostly in research and for consulting. Questionnaire and interview results uncover various user requests regarding USEtox usability. Results were systematically analyzed to translate user requests into recommendations to improve USEtox from a user perspective and were afterwards applied in the further USEtox development process. Conclusions We demonstrate that understanding interactions between USEtox and its users helps guiding model development and dissemination. USEtox-specific recommendations are to (1) respect the application context for different user types, (2) provide detailed guidance for interpreting model and factors, (3) facilitate consistent integration into LCA software and methods, (4) improve update/testing procedures, (5) strengthen communication between developers and users, and (6) extend model scope. By generalizing our recommendations to guide scientific model development in a broader context, we emphasize to acknowledge different levels of user expertise to integrate sound revision and update procedures and to facilitate modularity, data import/export, and incorporation into relevant software and databases during model design and development. Our fully documented approach can inspire performing similar surveys on other LCA-related tools to consistently analyze user requirements and provide improvement recommendations based on scientific user analysis methods.

Description: Purpose Numerous publications in the last years stressed the growing importance of nanotechnology in our society, highlighting both positive as well as in the negative topics. Life cycle assessment (LCA) is amongst the most established and best-developed tool in the area of product-related assessment. In order to use this tool in the area of nanotechnology, clear rules of how emissions of nanomaterials should be taken into account on the level of life cycle inventory (LCI) modelling are required—i.e. what elements and properties need to be reported for an emission of a nanomaterial. The objective of this paper is to describe such a framework for an adequate and comprehensive integration of releases of nanomaterials. Methods With a three-step method, additional properties are identified that are necessary for an adequate integration of releases of nanomaterials into LCA studies. Result and discussion In the first step, a comprehensive characterisation of the release of a nanomaterial is compiled—based on reviewing scientific publications, results from expert workshops and publications from public authorities and international organisations. In the second step, this comprehensive overview is refined to a list containing only those properties that are effectively relevant for LCA studies—i.e. properties that influence the impacts in the areas of human toxicity and ecotoxicity, respectively. For this, an academic approach is combined with a second, more practical, view point, resulting together in a prioritisation of this list of properties. Finally, in a third step, these findings are translated into the LCA language—by showing how such additional properties could be integrated into the current LCA data formats for a broader use by the LCA community. Conclusions As a compromise between scholarly knowledge and the (toxicological) reality, this paper presents a clear proposal of an LCI modelling framework for the integration of releases of nanomaterials in LCA studies. However, only the broad testing of this framework in various situations will show if the suggested simplifications and reductions keep the characterisation of releases of nanomaterials specific enough and/or if assessment is accurate enough. Therefore, a next step has to come from the impact assessment, by the development of characterisation factors as a function of size and shape of such releases.

Description: Purpose This study aims to compare the life cycle greenhouse gas (GHG) emissions of two cellulosic bioenergy pathways (i.e., bioethanol and bioelectricity) using different references and functional units. It also aims to address uncertainties associated with a comparative life cycle analysis (LCA) for the two bioenergy pathways. Methods We develop a stochastic, comparative life cycle GHG analysis model for a switchgrass-based bioenergy system. Life cycle GHG offsets of the biofuel and bioelectricity pathways for cellulosic bioenergy are compared. The reference system for bioethanol is the equivalent amount of gasoline to provide the same transportation utility (e.g., vehicle driving for certain distance) as bioethanol does. We use multiple reference systems for bioelectricity, including the average US grid, regional grid in the USA according to the North American Electric Reliability Corporation (NERC), and average coal-fired power generation, on the basis of providing the same transportation utility. The functional unit is one unit of energy content (MJ). GHG offsets of bioethanol and bioelectricity relative to reference systems are compared in both grams carbon dioxide equivalents per hectare of land per year (g CO 2 -eq/ha-yr) and grams carbon dioxide equivalents per vehicle kilometer traveled (g CO 2 -eq/km). For the latter, we include vehicle cycle to make the comparison meaningful. To address uncertainty and variability, we derive life cycle GHG emissions based on probability distributions of individual parameters representing various unit processes in the life cycle of bioenergy pathways. Results and discussion Our results show the choice of reference system and functional unit significantly changes the competition between switchgrass-based bioethanol and bioelectricity. In particular, our results show that the bioethanol pathway produces more life cycle GHG emissions than the bioelectricity pathway on a per unit energy content or a per unit area of crop land basis. However, the bioethanol pathway can offer more GHG offsets than the bioelectricity pathway on a per vehicle kilometer traveled basis when using bioethanol and bioelectricity for vehicle operation. Given the current energy mix of regional grids, bioethanol can potentially offset more GHG emissions than bioelectricity in all grid regions of the USA. Conclusions The reference and functional unit can change bioenergy pathway choices. The comparative LCA of bioenergy systems is most useful for decision support only when it is spatially explicit to address regional specifics and differences. The difference of GHG offsets from bioethanol and bioelectricity will change as the grid evolves. When the grids get cleaner over time, the favorability of bioethanol for GHG offsets increases.

Description: Purpose This article is the third of a series of articles presenting the results of research on the implementation of life cycle management tools in small- and medium-sized companies in Poland. The purpose of the three-part series of articles is to present the results of research on the implementation of life cycle tools in Polish small and medium enterprises (SMEs). This work is part of a project financed by the Polish Agency for Enterprise Development (PAED) which began in February 2011. It was carried out by the Wielkopolska Quality Institute—a business environment institution associated with the Polish Centre for LCA (PCLCA). The main practical objective of the project was to support SMEs in their business development, e.g. by expanding their horizons beyond the sphere of their operation and identifying new areas for the improvement and promotion of the products and services on offer. The specific objective of the analysis involving the assessment of life-cycle costs of products and services was an attempt to answer the question to determine whether the assessment carried out in accordance with the life-cycle cost (LCC) methodology is a good tool for cost management in this type of business. Part 3 describes the results of studies on the assessment of the implementation of LCC in SMEs conducted in 50 companies involved in the project. Methods In order to assess the effectiveness of the project and the effectiveness of the implementation of LCA and LCC, a survey was conducted of small- and medium-sized businesses where the implementation works had been fully completed. In total, 50 organisations agreed to participate in the LCC survey (while 46 in the LCA—part 2 paper), which was 71 % of all the companies where the LCA and LCC studies had been carried out within the project. The survey was conducted using individual in-depth interviews. Questions to the representatives of the companies referred both to aspects of their operating in the market (characteristics of a company, its market share, management systems, environmental policy, suppliers, clients) and the implementation of their environmental service (assessment of its effectiveness, motivation, difficulties in its implementation), as well as opinions on the potential applications of LCA in their current operations. Results and discussion The experience and observations of LCC experts resulting from their cooperation with the analysed organisations are largely supported by the results of the survey. The overall impression gained from the project is that the small- and medium-sized enterprises considered have a problem with accepting and understanding the life-cycle perspective, and show limited interest in taking liability for environmental and cost aspects beyond the mandatory legal standards and boundaries of their business operations. Nevertheless, the LCC analyses aroused much bigger interest among the companies than the environmental due to the fact that the cost aspects in companies undergoing normal development are seen as an important source of information about the structure of the costs generated with respect to the products or services provided. It is important to note that a very important factor encouraging businesses to join the studies was the fact that they were cost-free. Moreover, the planned introduction of a new product onto the market was the argument that often influenced the decision to implement the LCC. The survey has shown that companies rarely perform cost analyses including all stages of the life cycle of a product or service. Although the awareness of the importance of conducting economic researches for the entire life cycle of a product or service is great, it turned out to be problematic to unambiguously define the practical use of such an analysis, at least at the present stage of development of the companies surveyed. Conclusions The results obtained in the survey indicate that in the case of simple products, with a short life cycle, complex cost analyses may seem less useful. For more complex products or services, with long periods of use, high reliability required, and high operating costs, the analyses presented are useful tools that increase the economic efficiency of the projects implemented. It appears that from the point of view of polish SMEs, the usefulness of an LCA is seen mainly from the angle of opportunities for cost reduction (preferably in business) and increased sales (marketing). A good solution would be to conduct relatively simple, but integrated LCA/LCC analyses in SMEs so that the companies would clearly see the economic effects of the proposed environmental improvements.

Description: Purpose India’s biofuel programme relies on ethanol production from sugarcane molasses. However, there is limited insight on environmental impacts across the Indian ethanol production chain. This study closes this gap by assessing the environmental impacts of ethanol production from sugarcane molasses in Uttar Pradesh, India. A comparative analysis with south-central Brazilian sugarcane ethanol is also presented to compare the performance of sugarcane molasses-based ethanol with sugarcane juice-based ethanol. Methods The production process is assessed by a cradle-to-gate life cycle assessment. The multifunctionality problem is solved by applying two variants of system expansion and economic allocation. Environmental impacts are assessed with Impact 2002+ and results are presented at the midpoint level for greenhouse gas emissions, non-renewable energy use, freshwater eutrophication and water use. Furthermore, results include impacts on human health and ecosystem quality at the damage level. Sensitivity analysis is also performed on key contributing parameters such as pesticides, stillage treatment and irrigation water use. Results and discussion It is found that, compared to Brazilian ethanol, Indian ethanol causes lower or comparable greenhouse gas emissions (0.09–0.64 kgCO 2eq /kg ethanolIN , 0.46–0.63 kgCO 2eq /kg ethanolBR ), non-renewable energy use (−0.3–6.3 MJ/kg ethanolIN , 1–4 MJ/kg ethanolBR ), human health impacts (3.6 · 10 −6 DALY/kg ethanolIN , 4 · 10 −6  DALY/kg ethanolBR ) and ecosystem impairment (2.5 PDF · m 2  · year/kg ethanolIN , 3.3 PDF · m 2  · year/kg ethanolBR ). One reason is that Indian ethanol is exclusively produced from molasses, a co-product of sugar production, resulting in allocation of the environmental burden. Additionally, Indian sugar mills and distilleries produce surplus electricity for which they receive credits for displacing grid electricity of relatively high CO 2 emission intensity. When economic allocation is applied, the greenhouse gas emissions for Indian and Brazilian ethanol are comparable. Non-renewable energy use is higher for Indian ethanol, primarily due to energy requirements for irrigation. For water use and related impacts, Indian ethanol scores worse due groundwater irrigation, despite the dampening effect of allocation. The variation on greenhouse gas emissions and non-renewable energy use of Indian mills is much larger for high and low performance than the respective systems in Brazil. Conclusions Important measures can be taken across the production chain to improve the environmental performance of Indian ethanol production (e.g. avoiding the use of specific pesticides, avoiding the disposal of untreated stillage, transition to water efficient crops). However, to meet the targets of the Indian ethanol blending programme, displacement effects are likely to occur in countries which export ethanol. To assess such effects, a consequential study needs to be prepared.

Description: Purpose The possibilities for full life cycle assessment (LCA) of new Information and Communication Technology (ICT) products are often limited, so simplification approaches are needed. The aim of this paper is to investigate possible simplifications in LCA of a mobile phone and to use the results to discuss the possibilities of LCA simplifications for ICT products in a broader sense. Another aim is to identify processes and data that are sensitive to different methodological choices and assumptions related to the environmental impacts of a mobile phone. Methods Different approaches to a reference LCA of a mobile phone was tested: (1) excluding environmental impact categories, (2) excluding life cycle stages/processes, (3) using secondary process data from generic databases, (4) using input-output data and (5) using a simple linear relationship between mass and embodied emissions. Results and discussion It was not possible to identify one or a few impact categories representative of all others. If several impact categories would be excluded, information would be lost. A precautionary approach of not excluding impact categories is therefore recommended since impacts from the different life cycle stages vary between impact categories. Regarding use of secondary data for an ICT product similar to that studied here, we recommend prioritising collection of primary (specific) data on energy use during production and use, key component data (primarily integrated circuits) and process-specific data regarding raw material acquisition of specific metals (e.g. gold) and air transport. If secondary data are used for important processes, the scaling is crucial. The use of input-output data can be a considerable simplification and is probably best used to avoid data gaps when more specific data are lacking. Conclusions Further studies are needed to provide for simplified LCAs for ICT products. In particular, the end-of-life treatment stage need to be further addressed, as it could not be investigated here for all simplifications due to data gaps.

Description: Purpose Waste management for end-of-life (EoL) smartphones is a growing problem due to their high turnover rate and concentration of toxic chemicals. The versatility of modern smartphones presents an interesting alternative waste management strategy: repurposing. This paper investigates the environmental impact of smartphone repurposing as compared to traditional refurbishing using Life Cycle Assessment (LCA). Methods A case study of repurposing was conducted by creating a smartphone “app” that replicates the functionality of an in-car parking meter. The environmental impacts of this prototype were quantified using waste management LCA methodology. Studied systems included three waste management options: traditional refurbishment, repurposing using battery power, and repurposing using a portable solar charger. The functional unit was defined as the EoL management of a used smartphone. Consequential system expansion was employed to account for secondary functions provided; avoided impacts from displaced primary products were included. Impacts were calculated in five impact categories. Break-even displacement rates were calculated and sensitivity to standby power consumption were assessed. Results and discussion LCA results showed that refurbishing creates the highest environmental impacts of the three reuse routes in every impact category except ODP. High break-even displacement rates suggest that this finding is robust within a reasonable range of primary cell phone displacement. The repurposed smartphone in-car parking meter had lower impacts than the primary production parking meter. Impacts for battery-powered devices were dominated by use-phase charging electricity, whereas solar-power impacts were concentrated in manufacturing. Repurposed phones using battery power had lower impacts than those using solar power, however, standby power sensitivity analysis revealed that solar power is preferred if the battery charger is left plugged-in more than 20 % of the use period. Conclusions Our analysis concludes that repurposing represents an environmentally preferable EoL option to refurbishing for used smartphones. The results suggest two generalizable findings. First, primary product displacement is a major factor affecting whether any EoL strategy is environmentally beneficial. The benefit depends not only on what is displaced, but also on how much displacement occurs; in general, repurposing allows freedom to target reuse opportunities with high “displacement potential.” Second, the notion that solar power is preferable to batteries is not always correct; here, the rank-order is sensitive to assumptions about user behavior.

Description: Purpose Overfishing is a relevant issue to include in all life cycle assessments (LCAs) involving wild caught fish, as overfishing of fish stocks clearly targets the LCA safeguard objects of natural resources and natural ecosystems. Yet no robust method for assessing overfishing has been available. We propose lost potential yield (LPY) as a midpoint impact category to quantify overfishing, comparing the outcome of current with target fisheries management. This category primarily reflects the impact on biotic resource availability, but also serves as a proxy for ecosystem impacts within each stock. Methods LPY represents average lost catches owing to ongoing overfishing, assessed by simplified biomass projections covering different fishing mortality scenarios. It is based on the maximum sustainable yield concept and complemented by two alternative methods, overfishing though fishing mortality (OF) and overfishedness of biomass (OB), that are less data-demanding. Results and discussion Characterization factors are provided for 31 European commercial fish stocks in 2010, representing 74 % of European and 7 % of global landings. However, large spatial and temporal variations were observed, requiring novel approaches for the LCA practitioner. The methodology is considered compliant with the International Reference Life Cycle Data System (ILCD) standard in most relevant aspects, although harmonization through normalization and endpoint characterization is only briefly discussed. Conclusions Seafood LCAs including any of the three approaches can be a powerful communicative tool for the food industry, seafood certification programmes, and for fisheries management.

Description: The 54th LCA forum was held on December 5, 2013 to launch the fourth generation ecological scarcity method, applied to Switzerland. This conference report presents the highlights of the LCA forum. The ecological scarcity method belongs to the family of distance-to-target methods and is based on politically and legally defined environmental goals. The application of the method in industry and politics as well as its benefits, the main elements of the method and new elements such as the assessment of abiotic resources, global land use, noise and nuclear waste are presented. The losses (and not the extraction) of abiotic resources are characterised with the abiotic depletion potential. Land use impacts on flora and fauna biodiversity are quantified per land use type and for 14 different biomes. Transport noise is assessed based on the number of highly annoyed persons. Finally, nuclear waste is characterised using the radio toxicity index, a parameter commonly used in the nuclear industry. In three policy-making areas, LCA in general and the ecological scarcity method in particular are being applied: waste policy, biofuels tax exemption and Green Economy. Practical applications in administration and industry show that the eco-factors are considered useful in decision making because they cover a broad range of environmental impacts aggregated to a single score. The results of first applications and comparisons showed that the switch from third to fourth generation eco-factors hardly affects the results and conclusions although there are some significant changes in the eco-factor of individual pollutants. It was concluded that the fourth generation is a moderate evolution from the third generation published in 2008. It is considered crucial to allow for single-score methods as they allow to assess environmental impacts comprehensively and to identify environmental hot spots. The method presented thus is suited for a “true and fair” reporting on environmental information.

Description: Purpose Life cycle assessment (LCA) has been increasingly implemented in analyzing the environmental performance of buildings and construction projects. To assess the life cycle environmental performance, decision-makers may adopt the two life cycle impact assessment (LCIA) approaches, namely the midpoint and endpoint models. Any imprudent usage of the two approaches may affect the assessment results and thus lead to misleading findings. ReCiPe, a well-known work, includes a package of LCIA methods to provide assessments on both midpoint and endpoint levels. This study compares different potential LCIA results using the midpoint and endpoint approaches of ReCiPe based on the assessment of a commercial building in Hong Kong. Methods This paper examines 23 materials accounting for over 99 % of the environmental impacts of all the materials consumed in commercial buildings in Hong Kong. The midpoint and endpoint results are compared at the normalization level. A commercial building in Hong Kong is further studied to provide insights as a real case study. The ranking of impact categories and the contributions from various construction materials are examined for the commercial building. Influence due to the weighting factors is discussed. Results and discussion Normalization results of individual impact categories of the midpoint and endpoint approaches are consistent for the selected construction materials. The difference in the two approaches can be detected when several impact categories are considered. The ranking of materials is slightly different under the two approaches. The ranking of impact categories demonstrates completely different features. In the case study of a commercial building in Hong Kong, the contributions from subprocesses are different at the midpoint and endpoint. The weighting factors can determine not only the contributions of the damage categories to the total environment, but also the value of a single score. Conclusions In this research, the midpoint and endpoint approaches are compared using ReCiPe. Information is whittled down from the inventories to a single score. Midpoint results are comprehensive while endpoint results are concise. The endpoint approach which provides additional information of damage should be used as a supplementary to the midpoint model. When endpoint results are asked for, a LCIA method like ReCiPe that provides both the midpoint and endpoint analysis is recommended. This study can assist LCA designers to interpret the midpoint and endpoint results, in particular, for the assessment of commercial buildings in Hong Kong.

Description: Purpose A framework for the inclusion of land use impact assessment and a set of land use impact indicators has been recently proposed for life cycle assessment (LCA) and no case studies are available for forest biomass. The proposed methodology is tested for Scandinavian managed forestry; a comparative case study is made for energy from wood, agro-biomass and peat; and sensitivity to forest management options is analysed. Methods The functional unit of this comparative case study is 1 GJ of energy in solid fuels. The land use impact assessment framework of the United Nations Environment Programme and the Society of Environmental Toxicology and Chemistry (UNEP-SETAC) is followed and its application for wood biomass is critically analysed. Applied midpoint indicators include ecological footprint and human appropriation of net primary production, global warming potential indicator for biomass (GWP bio -100) and impact indicators proposed by UNEP-SETAC on ecosystem services and biodiversity. Options for forest biomass land inventory modelling are discussed. The system boundary covers only the biomass acquisition phase. Management scenarios are formulated for forest and barley biomass, and a sensitivity analysis focuses on impacts of land transformations for agro-biomass. Results and discussion Meaningful differences were found in between solid biofuels from distinct land use classes. The impact indicator results were sensitive to land occupation and transformation and differed significantly from inventory results. Current impact assessment method is not sensitive to land management scenarios because the published characterisation factors are still too coarse and indicate differences only between land use types. All indicators on ecosystem services and biodiversity were sensitive to the assumptions related with land transformation. The land occupation (m 2 a) approach in inventory was found challenging for Scandinavian wood, due to long rotation periods and variable intensities of harvests. Some suggestions of UNEP-SETAC were challenged for the sake of practicality and relevance for decision support. Conclusions Land use impact assessment framework for LCA and life cycle impact assessment (LCIA) indicators could be applied in a comparison of solid bioenergy sources. Although forest bioenergy has higher land occupation than agro-bioenergy, LCIA indicator results are of similar magnitude or even lower for forest bioenergy. Previous literature indicates that environmental impacts of land use are significant, but it remains questionable if these are captured with satisfactory reliability with the applied LCA methodology, especially for forest biomass. Short and long time perspectives of land use impacts should be studied in LCA with characterisation factors for all relevant timeframes, not only 500 years, with a forward-looking perspective. Characterisation factors need to be modelled further for different (forest) land management intensities and for peat excavation.

Description: Purpose When product systems are optimized to minimize environmental impacts, uncertainty in the process data may impact optimal decisions. The purpose of this article is to propose a mathematical method for life cycle assessment (LCA) optimization that protects decisions against uncertainty at the life cycle inventory (LCI) stage. Methods A robust optimization approach is proposed for decision making under uncertainty in the LCI stage. The proposed approach incorporates data uncertainty into an optimization problem in which the matrix-based LCI model appears as a constraint. The level of protection against data uncertainty in the technology and intervention matrices can be controlled to reflect varying degrees of conservatism. Results and discussion A simple numerical example on an electricity generation product system is used to illustrate the main features of this methodology. A comparison is made between a robust optimization approach, and decision making using a Monte Carlo analysis. Challenges to implement the robust optimization approach on common uncertainty distributions found in LCA and on large product systems are discussed. Supporting source code is available for download at https://github.com/renwang/Robust_Optimization_LCI_Uncertainty . Conclusions A robust optimization approach for matrix-based LCI is proposed. The approach incorporates data uncertainties into an optimization framework for LCI and provides a mechanism to control the level of protection against uncertainty. The tool computes optimal decisions that protects against worst-case realizations of data uncertainty. The robust optimal solution is conservative and is able to avoid the negative consequences of uncertainty in decision making.

Description: Purpose Biopolymers are considered to be environmentally friendlier than petroleum-based polymers, but little is known about their environmental performance against petroleum-based products. This paper presents the results of a life cycle assessment (LCA) of two prototype biocomposite formulations produced by extrusion of wood fibre with either polylactic acid (PLA) or a blend of PLA and locally produced thermoplastic starch (TPS). Methods The study followed the LCA methodology outlined in the two standards set out by the International Organization for Standardization (ISO): ISO 14040 and ISO 14044 of 2006. A life cycle inventory (LCI) for the biocomposite formulations was developed, and a contribution analysis was performed to identify the significant inputs. Environmental performances of the two formulations were then compared with each other and polypropylene (PP), a petroleum-based polymer. The US Environmental Protection Agency’s impact assessment method, “TRACI: The Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts”, was combined with Cumulative Energy Demand (a European method) in order to characterize the inventory flows. Environmental impact categories chosen for the analysis were the following: global warming, stratospheric ozone depletion, acidification of land and water, eutrophication, smog, human health (respiratory, carcinogenic, and non-carcinogenic) effects and ecotoxicity. Results and discussion We found that PLA is the significant input which contributes mostly to fossil fuel consumption, acidification and respiratory and smog effects. Impacts from PLA transport from the faraway source significantly added more burden to its contributions. TPS causes less environmental burden compared to PLA; the environmental performance of the biocomposite improved when a blend of PLA and TPS is used in formulating the biocomposite. The two formulations performed better than PP in all the environmental impact categories except eutrophication effects, which is important on a regional basis. Conclusions The following conclusions were drawn from this study: PLA is the environmentally significant input among the three raw materials. TPS causes less environmental burden than PLA. Environmental performance of the biocomposite improves in the life cycle energy consumption, fossil energy use, ozone depletion and non-carcinogenic impact categories when a blend of PLA and TPS is used. The biocomposite can outperform PP in all the impact categories except eutrophication effects if manufactured using hydroelectricity. The biopolymer could be a potential alternative to PP as it could cause less of a burden to the environment on a cradle-to-gate basis. Environmental impacts at the complete life cycle levels should be looked into in order to fully understand its potential.

Description: Purpose This paper compares environmental impacts of two packaging options for contrast media offered by GE Healthcare: + PLUS PAK™ polymer bottle and traditional glass bottle. The study includes all relevant life cycle stages from manufacturing to use and final disposal of the bottles and includes evaluation of a variety of end-of-life disposal scenarios. The study was performed in accordance with the international standards ISO 14040/14044, and a third-party critical review was conducted. Methods The functional unit is defined as the packaging of contrast media required to deliver one dose of 96 mL to a patient for an X-ray procedure. Primary data are from GE Healthcare and its suppliers; secondary data are from the ecoinvent database and the literature. A variety of end-of-life disposal scenarios are explored using both cutoff and market-based allocation. Impact assessment includes human health (midpoint) and ecosystems and resources (end point) categories from ReCiPe (H) and cumulative energy demand. Sensitivity analyses include (1) bottle size, (2) secondary packaging, (3) manufacturing electricity, (4) glass recycled content, (5) scrap rate, (6) distribution transport, (7) contrast media, and (8) choice of impact assessment method. Uncertainty analysis is performed to determine how data quality affects the study conclusions. Results and discussion This study indicates that the polymer bottle outperforms the glass bottle in every environmental impact category considered. Bottle components are the most significant contributors, and the vial body has the highest impacts among bottle components for both polymer and glass bottles. The polymer bottle exhibits lower impact in all impact categories considered regardless of the following: end-of-life treatment (using either cutoff or market-based allocation), bottle size, manufacturing electricity grid mix, glass recycled content, scrap rate, contrast media, distribution transport (air vs. ocean), and choice of impact assessment method. Secondary packaging can be a major contributor to impact. The polymer bottle has considerably lower impact compared to the glass bottle for all multi-pack configurations, but the comparison is less clear for single-pack configurations due to significantly higher packaging material used per functional dose, resulting in proportionally higher impacts in all impact categories. Conclusions The lower impacts of the polymer bottle for this packaging application can be attributed to lower material and manufacturing impacts, lower distribution impacts, and lower end-of-life disposal impacts. The results of this study suggest that using polymer rather than glass bottles provides a means by which to lower environmental impact of contrast media packaging.

Description: Purpose Chemicals produced via chlor-alkali electrolysis are widely used throughout the water industry worldwide, with treatment chemicals often the second largest source of environmental impacts from potable water production after electricity use. Population-driven increases in the future demand for potable water will require concomitant increases in the production of water treatment chemicals, with the associated environmental impacts of chemicals production primarily arising from the additional demand for electricity. Due to the dominance of electricity in the environmental performance of chlor-alkali chemicals, assessment of the future environmental impacts of potable water production is largely dependent on proper identification of the marginal source of electricity. In this paper, we present a consequential cradle-to-gate carbon footprint (cCF) for the most widely used chlor-alkali-produced disinfectant (sodium hypochlorite (13 % w/w )) and coagulant (ferric chloride (42 % w/w )) in Australia, with special emphasis placed upon the identification of future marginal electricity supply and the substitution of hydrogen gas and sodium hydroxide during production. While this analysis is presented in an Australian context, commonalities in potable water and chlor-alkali chemical production processes internationally give the findings a broader relevance. Methods Consequential models for sodium hypochlorite (13 % w/w ) and ferric chloride (42 % w/w ) production were developed, and the identification of the marginal source of electricity was modelled using a “simple marginal technology” approach via operationalisation of the Weidema framework and a “complex marginal technology” using a partial equilibrium model. For the simple marginal technology, the levelised cost of electricity was used to select the most competitive energy generation technologies and those most relevant for the Australian market. For the complex marginal technology, the energy sector model was used to simulate the most likely electricity supply mix. Details of the different paths taken in the substitution of hydrogen gas and sodium hydroxide are also presented. To allow for proper incorporation of uncertainties arising from these key factors in the cCF, several scenarios were developed covering fuel and carbon prices for identifying the marginal supply mix of electricity, as well as the likely production routes for sodium carbonate in the context of sodium hydroxide substitution. Results and discussion cCF results of sodium hypochlorite (13 % w/w ) and ferric chloride (42 % w/w ) are presented using simple and complex marginal technologies, and the implications of choosing one marginal technology over the other in the context of water treatment chemicals are presented. For the simple marginal technology approach, the global warming potential (GWP) per megagram of chemical varied from 68 to 429 kg CO 2 -eq for sodium hypochlorite (13 % w/w ) and 59–1,020 kg CO 2 -eq for ferric chloride (42 % w/w ). For the complex marginal technology approach, the GWP per megagram of chemical varied from 266 to 332 kg CO 2 -eq for sodium hypochlorite (13 % w/w ) and 214–629 kg CO 2 -eq for ferric chloride (42 % w/w ). Insights are given in relation to the impact of the price of fossil fuels, the carbon price, and the different substitution routes. Conclusions The use of a partial equilibrium model (PEM) has enabled a better understanding of the variability of the results in this study. For example, the use of PEM for the identification of the complex marginal source of electricity shows that, for the case of Australia, any benefit from a carbon price is lost with high prices of natural gas due to the incentive to use cheaper fuels such as black and brown coal. Likewise, the use of explorative scenarios was decisive to manage the inherent uncertainty of the parameters included in the model. In relation to substitution, the case of ferric chloride (42 % w/w ) indicated that using only one substitution route was not enough to fully understand the potential continuum of cCF results. The simple marginal approach, where an exclusive marginal source of electricity or substitution route is considered, presents significant risks for the modelling accuracy of the cCF as shown here for sodium hypochlorite (13 % w/w ) and ferric chloride (42 % w/w ), therefore, it is not recommended.

Description: Purpose This article summarizes student performance and survey data from a recent massive open online course (MOOC) on life cycle assessment (LCA). Its purpose is to shed light on student learning outcomes, challenges, and success factors, as well as on improvement opportunities for the MOOC and the role of online courses in LCA education in general. Methods Student survey data and course performance data were compiled, analyzed, and interpreted for 1257 students who completed a pre-course survey and 262 students who completed a post-course survey. Both surveys were designed to assess student learning outcomes, topical areas of difficulty, changing perceptions on the nature of LCA, and future plans after completing the MOOC. Results and discussion Results suggest that online courses can attract and motivate a large number of students and equip them with basic analytical skills to move on to more advanced LCA studies. However, results also highlight how MOOCs are not without structural limitations, especially related to mostly “locked in” content and the impracticality of directly supporting individual students, which can create challenges for teaching difficult topics and conveying important limitations of LCA in practice. Conclusions Online courses, and MOOCs in particular, may present an opportunity for the LCA community to efficiently recruit and train its next generations of LCA analysts and, in particular, those students who might not otherwise have an opportunity to take an LCA course. More surveys should be conducted by LCA instructors and researchers moving forward to enable scientific development and sharing of best practice teaching methods and materials.

Description: Purpose The number of scrap tires generated in China has grown dramatically every year. Generation of ground rubber from scrap tires is the dominant management option in China. It is necessary to assess the environmental impacts of ground rubber production from scrap tires to provide technical advices on a cleaner production. Methods Production of ground rubber from recycled scrap tires consist of three steps: rubber powder preparation, devulcanization, and refining. A process life cycle assessment (LCA) of ground rubber production from scrap tires is carried out, and Eco-indicator 99 method coupled with ecoinvent database is applied to evaluate the environmental impacts of this process. Results and discussion During the ground rubber production stage, the impact factor of respiratory inorganic is the most serious one. Devulcanization has the highest environmental load of about 66.2 %. Moreover, improvement on the flue gas treatment contributes to a cleaner production and a more environmental-friendly process. Applying clean energy can largely reduce environmental load by about 21.5 %. Conclusions The results can be a guidance to reduce environmental load when producing ground rubber from scrap tires. Meanwhile, increasing energy efficiency, improving environmental protection equipment, and applying clean energy are the effective measures to achieve this goal.

Description: Purpose Due to the large environmental challenges posed by the transport sector, reliable and state-of-the art data for its life cycle assessment is essential for enabling a successful transition towards more sustainable systems. In this paper, the new electric passenger car transport and vehicle datasets, which have been developed for ecoinvent version 3, are presented. Methods The new datasets have been developed with a strong modular approach, defining a hierarchy of datasets corresponding to various technical components in the vehicle. A vehicle is therefore modelled by linking together the various component datasets. Also, parameters and mathematical formulas have been introduced in order to define the amount of exchanges in the datasets through common transport and vehicle characteristics. This supports users in the choice of the amount of exchanges and enhances the transparency of the dataset. Results The new transport dataset describes the transport over 1 km with a battery electric passenger car taking into account the vehicle production and end of life, the energy consumption due to the use phase, non-exhaust emissions, maintenance and road infrastructure. The dataset has been developed and is suitable for a compact class vehicle. Conclusions A new electric passenger car transport dataset has been developed for version 3 of the ecoinvent database which exploits modularisation and parameters with the aim of facilitating users in adapting the data to their specific needs. Apart from the direct use of the transport dataset for background data, the various datasets for the different components can also be used as building blocks for virtual vehicles.

Description: Purpose Over the last decade, the rehabilitation/renovation of existing buildings has increasingly attracted the attention of scientific community. Many studies focus intensely on the mechanical and energy performance of retrofitted/renovated existing structures, while few works address the environmental impact of such operations. In the present study, the environmental impact of typical retrofit operations, referred to masonry structures, is assessed. In particular, four different structural options are investigated: local replacement of damaged masonry, mortar injection, steel chain installation, and grid-reinforced mortar application. Each different option is analyzed with reference to proper normalized quantities. Thus, the results of this analysis can be used to compute the environmental impact of real large-scale retrofit operations, once the amount/extension of them is defined in the design stage. The final purpose is to give to designers the opportunity to monitor the environmental impact of different retrofit strategies and, once structural requirements are satisfied, identify for each real case the most suitable retrofit option. Methods The environmental impact of the structural retrofit options is assessed by means of a life-cycle assessment (LCA) approach. A cradle to grave system boundary is considered for each retrofit process. The results of the environmental analysis are presented according to the data format of the Environmental Product Declaration (EPD) standard. Indeed, the environmental outcomes are expressed through six impact categories: global warming, ozone depletion, eutrophication, acidification, photochemical oxidation, and nonrenewable energy. Results and discussion For each retrofit option, the interpretation analysis is conducted in order to define which element, material, or process mainly influenced the LCA results. In addition, the results revealed that the recycling of waste materials provides environmental benefits in all the categories of the LCA outcomes. It is also pointed out that a comparison between the four investigated options would be meaningful only once the exact amount of each operation is defined for a specific retrofit case. Conclusions This paper provides a systematic approach and environmental data to drive the selection and identification of structural retrofit options for existing buildings, in terms of sustainability performance. The final aim of this work is also to provide researchers and practitioners, with a better understanding of the sustainability aspects of retrofit operations. In fact, the environmental impacts of the retrofit options here investigated can be used for future research/practical activities, to monitor and control the environmental impact of structural retrofit operations of existing masonry buildings.

Description: Purpose An life cycle assessment (LCA) study of a field emission display (FED) television device was established. The first objective of this study was to get an up-to-date and comprehensive picture by applying the latest developments in the area of LCA, especially concerning the use of nanoparticles. In its second part, the study shows a comparison with today’s display technologies (i.e. CRT, LCD, plasma) and the timely development of the assessment of a FED television device. Methods This LCA study covers the complete life cycle of a FED television device in accordance with the ISO 14040 standard, from the extraction of raw materials until the final end-of-life treatment in a European WEEE recycling system. Two different functional units were applied in this study: For the in-depth analysis of the FED television device, an entire device along its complete life cycle was considered as functional unit—for the subsequent comparison with today’s display technologies, “one square-inch of display during 1 h of active use” was used as an appropriate functional unit. Main data source for the FED device was patent information; ecoinvent was used as default background database. Results and discussion The in-depth analysis of this FED television device shows a clear dominance of the production phase (independently of the impact category). Within the production of such a device, the electronics part (i.e. the printed wiring boards) shows the highest contribution—while, even when focussing on the glass and its various coating layers only, the carbon nanotubes (CNTs) production has a very minor influence. The releases of CNTs during the End-of-Life treatment do not contribute in a relevant manner to the overall impact neither—even when focussing on the “ecotoxicity potential” by using conservative CFs reported for this type of releases. Last but not least, the comparison with the existing television display technologies shows that an FED device has an environmental advantage over all three other technologies using the above stated functional unit of “one square-inch of display during 1 h of active use”. Conclusions Traditional impact categories as well as the ecotoxicity factor results in clear environmental advantages for an FED television device when comparing it to the three display technologies used today. Concerning the general issue of evaluating applications of manufactured nanomaterials in LCA studies, this case study shows the high relevance of an adequate integration of nanoparticle releases into LCA studies in order to achieve an actually comprehensive evaluation.

Description: Purpose Land use is a potentially important impact category in life cycle assessment (LCA) studies of buildings. Three research questions are addressed in this paper: Is land use a decisive factor in the environmental impact of buildings?; Is it important to include the primary land use of buildings in the assessment?; and How does the environmental performance of solid structure and timber frame dwellings differ when assessed by distinct available models for quantifying land use impacts? Methods This paper compares several operational land use impact assessment models, which are subsequently implemented in an LCA case study comparing a building constructed using timber frame versus a solid structure. Different models were used for addressing the different research questions. Results and discussion The results reveal that contrasting decisions may be supported by LCA study results, depending on whether or not and how land use is included in the assessment. The analysis also highlights the need to include the building land footprint in the assessment and to better distinguish building locations in current land use impact assessment models. Conclusions Selecting land use assessment models that are most appropriate to the goals of the study is recommended as different models assess different environmental issues related to land use. In general, the combination of two land use assessment methods for buildings is recommended, i.e. soil organic matter (SOM) of Milà i Canals and Eco-indicator 99.

Description: Purpose The paper provides an empirical assessment of an uninterruptible power supply (UPS) system based on hydrogen technologies (HT-UPS) using renewable energy sources (RES) with regard to its environmental impacts and a comparison to a UPS system based on the internal combustion engine (ICE-UPS). Methods For the assessment and comparison of the environmental impacts, the life-cycle assessment (LCA) method was applied, while numerical models for individual components of the UPS systems (electrolyser, storage tank, fuel cell and ICE) were developed using GaBi software. The scope of analysis was cradle-to-end of utilisation with functional unit 1 kWh of uninterrupted electricity produced. For the life-cycle inventory analysis, quantitative data was collected with on-site measurements on an experimental system, project documentation, GaBi software generic databases and literature data. The CML 2001 method was applied to evaluate the system’s environmental impacts. Energy consumption of the manufacturing phase was estimated from gross value added (GVA) and the energy intensity of the industry sector in the manufacturer’s country. Results and discussion In terms of global warming (GW), acidification (A), abiotic depletion (AD) and eutrophication (E), manufacturing phase of HT-UPS accounts for more than 97 % of environmental impacts. Electrolyser in all its life-cycle phases contributes above 50 % of environmental impacts to the system’s GW, A and AD. Energy return on investment (EROI) for the HT-UPS has been calculated to be 0.143 with distinction between renewable (roughly 60 %) and non-renewable energy resources inputs. HT-UPS’s life-cycle GW emissions have been calculated to be 375 g of CO 2 eq per 1 kWh of uninterruptible electric energy supplied. All these values have also been calculated for the ICE-UPS and show that in terms of GW, A and AD, the ICE-UPS has bigger environmental impacts and emits 1,190 g of CO 2 eq per 1 kWh of uninterruptible electric energy supplied. Both systems have similar operation phase energy efficiency. The ICE-UPS has a higher EROI but uses almost none RES inputs. Conclusions The comparison of two different technologies for providing UPS has shown that in all environmental impact categories, except eutrophication, the HT-UPS is the sounder system. Most of HT-UPS’s environmental impacts result from the manufacturing phase. On the contrary, ICE-UPS system’s environmental impacts mainly result from operational phase. Efficiency of energy conversion from electricity to hydrogen to electricity again is rather low, as is EROI, but these will likely improve as the technology matures.

Description: Purpose Polycyclic aromatic hydrocarbons (PAHs) have been identified as a major source of human health impact for many products in life cycle impact assessment (LCIA). However, this result is highly dependent on the LCIA method. Based on the USEtox model, this study aims to improve health impact estimates of 16 PAHs, explore the importance of emission profiles of PAH mixture, and illustrate how these improvements affect an LCIA case study. Methods We model the influences of two factors neglected in previous LCIA methods—black carbon adsorption and photolysis degradation—providing refined intake fractions. We use epidemiological data to estimate the carcinogenic effect factor of benzo[a]pyrene, rather than extrapolating it from animal toxicity tests as in previous studies. Toxicity equivalence factors (TEFs) are employed to estimate the 16 PAHs USEtox characterization factors, expressed in cancer cases per kilogram of PAH emitted. These are applied to determine industry-specific characterization factors of PAH mixtures for the aluminum industry, for domestic combustion, and for the overall world PAH emissions. Results and discussion Black carbon adsorption extends the persistency of PAHs with four or more rings and increases their intake fractions by up to 350 % even when photolysis is considered. The epidemiologically derived carcinogenic effect factor of benzo[a]pyrene increases 61-fold compared to previous studies, with 1.2 cancer cases per kilogram of benzo[a]pyrene intake. Source-specific emission profiles of PAHs, especially the fraction of benzo[a]pyrene and dibenz[a,h]anthracene in the mixture, have high influences on the health impact of mixtures. A default characterization factor of 5.7 × 10 −5 cancer cases per kilogram emitted is derived for the world PAH mixture. The proposed health impact estimates for PAH mixtures substantially affect overall health impacts for 1 kg aluminum produced and fall intermediary between the overestimated CML 2001 and the much lower ReCiPe results. Conclusions This study improves characterization factors of PAHs by incorporating considerations of black carbon adsorption, photolysis, and epidemiological data. It is important for future LCIA practices and epidemiological studies to include emissions of individual PAHs, specifically of dibenz[a,h]anthracene in addition to benzo[a]pyrene, when assessing human health impact of PAH mixtures.

Description: Purpose The shortage of agricultural water from freshwater sources is a growing concern because of the relatively large amounts needed to sustain food production for an increasing population. In this context, an impact assessment methodology is indispensable for the identification and assessment of the potential consequences of freshwater consumption in relation to agricultural water scarcity. This paper reports on the consistent development of midpoint and endpoint characterisation factors (CFs) for assessing these impacts. Methods Midpoint characterisation factors focus specifically on shortages in food production resulting from agricultural water scarcity. These were calculated by incorporating country-specific compensation factors for physical availability of water resources and socio-economic capacity in relation to the irrigation water demand for agriculture. At the endpoint, to reflect the more complex impact pathways from food production losses to malnutrition damage from agricultural water scarcity, international food trade relationships and economic adaptation capacity were integrated in the modelling with measures of nutritional vulnerability for each country. Results and discussion The inter-country variances of CFs at the midpoint revealed by this study were larger than those derived using previously developed methods, which did not integrate compensation processes by food stocks. At the endpoint level, both national and trade-induced damage through international trade were quantified and visualised. Distribution of malnutrition damage was also determined by production and trade balances for commodity groups in water-consuming countries, as well as dependency on import ratios for importer countries and economic adaptation capacity in each country. By incorporating the complex relationships between these factors, estimated malnutrition damage due to freshwater consumption at the country scale showed good correlation with total reported nutritional deficiency damage. Conclusions The model allows the establishment of consistent CFs at the midpoint and endpoint for agricultural water scarcity resulting from freshwater consumption. The complex relationships between food production supply and nutrition damage can be described by considering the physical and socio-economic parameters used in this study. Developed CFs contribute to a better assessment of the potential impacts associated with freshwater consumption in global supply chains and to life cycle assessment and water footprint assessments.

Description: Purpose Construction, as a sector of the economy, is a significant source of negative environmental impacts. The development of sustainable construction and associated initiatives are meant to reduce that impact. Buildings, for many reasons, are the complex objects of life cycle assessment (LCA) studies, which in this case can be particularly time-, data- and cost-consuming. Therefore, an attempt was made to explore the possibility of finding a methodological compromise between a full LCA and the compulsory energy certification. Six methodological variants, so called compromise solutions (CS) were identified and assessed. This article presents the results of the research project financed by the Polish Ministry of Science and Higher Education (N N309 078138) and coordinated by the Wood Technology Institute in Poznan. Methods The proposed CS were hybrids utilising, to various degrees, the environmental life cycle assessment (LCA) and energy certification. Life cycle impact assessments were carried out using IMPACT 2002+. Results and discussion The achieved results showed that the simplifications included in the energy certification lead to a significant drop in environmental impacts (by 77.9 % on average) in relation to the impact calculated for the full LCA. The results closest to the full LCA were achieved by the compromise solution no. 4 (CS4), where simplification included the exclusion from the life cycle of: transport processes, construction site, demolition, final disposal of waste, and the majority of elements associated with the use of the building. CS4 analysed all inventory inputs which were assessed with regard to the entire environmental profile. The following truncation levels were achieved for CS4—10.7 % (conventional masonry building), 9.9 % (passive masonry building), 8.3 % (conventional wooden building) and 7.4 % (passive wooden building), indicating that 90 % of the impact calculated for the full LCA was retained. Conclusions CS4 seems to be a rational compromise between the simplicity of the methodology and the environmental significance. With the exception of the energy usage for heating, hot water and ventilation, CS4 also proposes including, in the analysis, the production of building material and additional elements associated with the use stage, e.g. energy usage for home appliances and lighting, land occupation, water use and wastewater treatment. However, if we were to find a rational minimum, which is close to the energy certification, then a good improvement of this methodology would be to include energy usage for home appliances and lighting as well as introducing conversion indicators, based not only on the depletion of energy resources, but also factoring in global warming and respiratory effects/inorganic compounds. Moreover, it seems that the LCA methodology and, specifically, characterisation factors, are refined to such a degree and scientifically proved that it would be possible to use the knowledge with regard to LCA to establish such indicators for energy certification.

Description: Purpose In the past decade, several methods have emerged to quantify water scarcity, water availability and the human health impacts of water use. It was recommended that a quantitative comparison of methods should be performed to describe similar impact pathways, namely water scarcity and human health impacts from water deprivation. This is precisely the goal of this paper, which aims to (1) identify the key relevant modeling choices that explain the main differences between characterization models leading to the same impact indicators; (2) quantify the significance of the differences between methods, and (3) discuss the main methodological choices in order to guide method development and harmonization efforts. Methods The modeling choices are analysed for similarity of results (using mean relative difference) and model response consistency (through rank correlation coefficient). Uncertainty data associated with the choice of model are provided for each of the models analysed, and an average value is provided as a tool for sensitivity analyses. Results The results determined the modeling choices that significantly influence the indicators and should be further analysed and harmonised, such as the regional scale at which the scarcity indicator is calculated, the sources of underlying input data and the function adopted to describe the relationship between modeled scarcity indicators and the original withdrawal-to-availability or consumption-to-availability ratios. The inclusion or exclusion of impacts from domestic user deprivation and the inclusion or exclusion of trade effects both strongly influence human health impacts. At both midpoint and endpoint, the comparison showed that considering reduced water availability due to degradation in water quality, in addition to a reduction in water quantity, greatly influences results. Other choices are less significant in most regions of the world. Maps are provided to identify the regions in which such choices are relevant. Conclusions This paper provides useful insights to better understand scarcity, availability and human health impact models for water use and identifies the key relevant modeling choices and differences, making it possible to quantify model uncertainty and the significance of these choices in a specific regional context. Maps of regions where these specific choices are of importance were generated to guide practitioners in identifying locations for sensitivity analyses in water footprint studies. Finally, deconstructing the existing models and highlighting the differences and similarities has helped to determine building blocks to support the development of a consensual method.

Description: Purpose Livestock production is a recognized source of environmental impact, and this sector indirectly involves approximately 5 million people in Brazil. Livestock production includes nearly 1.5 million milk producers that use several different production systems. We chose the southern region of Brazil to evaluate the carbon footprint (CF) per 1 kg of energy-corrected milk (ECM) at the farm gate for different dairy production systems with the use of a good level of technology. Methods The dairy production systems were confined feedlot system, semi-confined feedlot system (including some grazing), and pasture-based grazing system. A sensitivity analysis of the dry matter intake (DMI) in each farming system and an uncertainty analysis based on a Monte Carlo (MC) simulation were performed to complement the discussion. The standards ISO 14040: 2006 and ISO 14044: 2006 were used for the comparative life cycle assessment (LCA) focused on the CF. The LCA software tool SimaPro 7.3.3 was used. Sensitivity analyses were conducted on input data for total digestible nutrients (TDN) and crude protein (CP) based on values from the literature. Results and discussion The comparative LCA showed that the confined feedlot system had a lower CF than the other systems studied. Total greenhouse gas emissions were 0.535 kg CO 2 e kg ECM −1 for the confined feedlot system, 0.778 kg CO 2 e kg ECM −1 for the semi-confined feedlot system, and 0.738 kg CO 2 e kg ECM −1 for the pasture-based system without considering the impact from direct land use change (dLUC). When considering these emissions, the CFs for grain and cottonseed production showed CF increases of 45.0, 36.9, and 37.3 % for the confined feedlot, semi-confined feedlot, and pasture-based systems, respectively. The results from the MC simulations showed low uncertainty through variations in TDN and CP. The coefficient of variation was 1.1 % for the confined feedlot, 0.7 % for the semi-confined feedlot, and 1.0 % for the pasture systems. Conclusions The uncertainties were due mainly to variations in N 2 O emissions from manure for the three systems. The CF in Brazilian systems was lower than almost all the results found in the literature, even when impacts from the dLUC were considered. The lowest CF in this case study was due mainly to the emission factor used for enteric fermentation.

Description: Purpose Regionalised characterisation factors (CFs) for watersheds around the world are available to assess water use-related environmental impacts. The main problem with using the watershed regionalisation level arises when a single CF is generated for large watersheds in countries where water availability and demand are not uniform. Additionally, water availability and use vary over time because of the effects of climate change and changing human lifestyles. These two factors are currently not taken into account in CFs, but should be included for the sake of the accuracy of LCA results. The aim of this research was to provide water stress index CFs at the sub-watershed spatial level for three temporal scenarios (present, short-term future and mid-term future) for Spain (Southern Europe), a country with considerable variability in water availability that is especially vulnerable to climate change effects. Methods CFs were calculated following the water stress index (WSI) definition of Pfister et al. (Environ Sci Technol 43(11):4098–4104, 2009 ). The WSI was calculated on a yearly basis for 117 sub-watersheds—compared to 56 regionalisation units provided in the original method—and for (i) the current situation: current water use and availability; (ii) short-term future: projections for 2015; and (iii) mid-term future: projections for 2030. The uncertainties of the CFs were calculated for each sub-watershed. Results and discussion Temporal trend analysis of the CFs showed a general relaxation of water stress over the short-term when compared to the current situation, followed by a new increase. Major differences were noticed in the WSIs calculated by Pfister et al. (Environ Sci Technol 43(11):4098–4104, 2009 ) using global data and maps and the WSIs calculated in this study using national and regional data. The WSIs under consideration of uncertainty were higher than the deterministic result for intermediate WSIs. Conclusions The CFs generated are useful compared with the CFs previously available because they improve evaluation of the water use-related impacts of present and future technologies with the life cycle stages located in Spain. We encourage LCA developers to update WSIs for other countries using information at the national level that is usually freely accessible.

Description: Purpose Rising corn prices in the USA due partly to increasing ethanol demands have led to a significant expansion of corn areas displacing natural vegetation and crops including cotton. From 2005 to 2009, cotton area harvested in the USA nearly halved with a reduction of 2.5 million hectares, while that of corn increased by 1.8 million hectares. However, environmental impacts of land shifts from cotton and corn have been largely neglected in literature. Methods In this study, we evaluate the environmental properties of US corn and cotton production and implications of land cover change from cotton to corn using state-specific data and life cycle impact assessment. Focusing on regional environmental issues, we cover both on-farm direct emissions such as different types of volatile organic compounds and pesticides and indirect emissions embodied in input materials such as fertilizers. TRACI 2.0 is used to evaluate the environmental impacts of these emissions. Results and discussion The results show that US cotton and corn productions per hectare on average generate roughly similar impacts for most impact categories such as eutrophication and smog formation. For water use and freshwater ecotoxicity, corn shows a smaller impact. When land shifts from cotton to corn in cotton-growing states , however, the process may aggravate most of the regional environmental impacts while relieving freshwater ecotoxicity impact. The differences in the two estimates are due mainly to underlying regional disparities in crop suitability that affects input structure and environmental emissions. Conclusions Our results highlight the importance of potential, unintended environmental impacts that cannot be adequately captured when average data are employed. Understanding the actual mechanisms under which certain policy induces marginal changes at a regional and local level is crucial for evaluating its net impact. Further, our study calls for an attention to biofuel-induced land cover change between crops and associated regional environmental impacts.

Description: Purpose Carbon-fibre-reinforced polymers (CFRP) have been developed by the aviation industry to reduce aircraft fuel burn and emissions of greenhouse gases. This study presents a life cycle assessment (LCA) of an all-composite airplane, based on a Boeing 787 Dreamliner. The global transition of aircraft to those of composite architecture is estimated to contribute 20–25 % of industry CO 2 reduction targets. A secondary stage of the cradle-to-grave analysis expands the study from an individual aircraft to the global fleet. Methods An LCA was undertaken utilising SimaPro 7.2 in combination with Ecoinvent. Eco-indicator 99 (E) V2.05 Europe EI 99 E/E was the chosen method to calculate the environmental impact of the inventory data. The previously developed aviation integrated model was utilised to construct a scenario analysis of the introduction of composite aircraft against a baseline projection, through to 2050, to model CO 2 emissions due to their particular relevance in the aviation sector. Results and discussion The analysis demonstrated CFRP structure results in a reduced single score environmental impact, despite the higher environmental impact in the manufacturing phase, due to the increased fossil fuel use. Of particular importance is that CFRP scenario quickly achieved a reduction in CO 2 and NO x atmospheric emissions over its lifetime, due to the reduced fuel consumption. The modelled fleet-wide CO 2 reduction of 14–15 % is less than the quoted emission savings of an individual aircraft (20 %) because of the limited fleet penetration by 2050 and the increased demand for air travel due to lower operating costs. Conclusions The introduction of aircraft based on composite material architecture has significant environmental benefits over their lifetime compared to conventional aluminium-based architecture, particularly with regards to CO 2 and NO x a result of reduced fuel burn. The constructed scenario analyses the interactions of technology and the markets they are applied in, expanding on the LCA, in this case, an observed fleet-wide reduction of CO 2 emission of 14–15 % compared to an individual aircraft of 20 %.

Description: Purpose The ISO 14044 standard for life cycle assessment (LCA) provides the reference decision hierarchy for dealing with multi-functional processes. We observe that, in practice, the consistent implementation of this hierarchy by LCA practitioners and LCA guidance document developers may be limited. In an attempt to explain this observation, and to offer suggestions as to how consistency in LCA practice might be improved, we identify and compare the rationales for (and limitations of) different common approaches to solving multi-functionality problems in LCA. Methods The different prevalent understandings of specific approaches for dealing with multi-functional processes were identified, and their respective rationales were analyzed. This takes into account identifying the implicit underlying assumptions regarding the nature and purpose of LCA that support each approach. Results and discussion We identified what we believe to be three internally consistent but mutually exclusive schools of thought amongst LCA practitioners, which differ in subtle but important ways in terms of their understanding of the nature and purpose of LCA, and the multi-functionality solutions necessary to support them. These three divisions follow two demarcations. The first is between consequential and attributional data modeling approaches. The second is between adherence to a natural science-based approach (privileging physical allocation solutions) and a socioeconomic approach (favoring economic allocation solutions) in attributional data modeling. Conclusions We conclude that the ISO 14044 multi-functionality hierarchy should explicitly differentiate between attributional and consequential data modeling applications. We question the feasibility and practical utility of system expansion (currently privileged in the ISO hierarchy) in attributional data modeling applications. We suggest that ISO 14044 should also make explicit its rationale for privileging natural science-based approaches to solving multi-functionality problems and to more clearly differentiate between natural science and social science-based approaches. We also call for the formulation of additional guidance for solving multi-functionality problems, in particular for justifying the use of lower-tier solutions from the ISO hierarchy when these are applied in LCA studies. We suggest that this additional guidance and clarity in ISO 14044 will contribute to increased consistency in LCA practice and also increase the potential for users of information from LCA studies to make informed decisions as to their relevance within the context of specific intended applications.

Description: Purpose Palm oil systems generate substantial amounts of biomass residues which are, according to best agricultural practices, preferably returned back to plantation in order to maintain soil fertility. However, there are often variations in this practice. Differences in economic status and possible treatment options for biomass residues determine the preferences to perform life cycle assessment (LCA), leading to a divergence in results. Difficulties when comparing LCA results based on literature are not unusual. The objectives of this paper are to provide guidelines for methodological choices that enable a systematic comparison of diverse scenarios for the treatment and valuation of empty fruit bunches (EFBs) and to explore effects of the scenarios on the environmental performances of a palm oil system. Methods Eleven scenarios were selected to address the possible EFB valuation and expanded boundaries with reference to the main palm oil system (EFBs applied as mulch, converted to compost or ethanol, treated in an incinerator, and sold as coproducts). The life cycle inventories were modeled based upon an Ecoinvent database. Solutions to multifunctional problems were suggested, including the application of system expansion, substitution, and partitioning, depending upon the nature of the scenarios. Results and discussion Comparison among LCA results based on the same multifunctional units (crude palm oil + palm kernel oil + palm kernel cake) can be accomplished only in cases where additional coproducts were utilized internally. Based on the global warming impact, the mulch option was preferred. The effect of the avoided process of producing synthetic fertilizers and the assumption that all parts of mulch are available as soil nutrient dominantly determined the final result. These need further verification. This study also demonstrates that the status of EFB as waste or goods is influential on the final results if the EFB is employed externally but has no effect if it is utilized internally. Conclusions The proposed guidelines provide methodological choices in terms of system boundary, functional unit, and solutions to multifunctional problems. The methods can be used to systematically compare LCA results of different treatment options and valuation of EFB. The preferred alternative for managing this biomass residue could improve environmental performances and orient toward best practices, such as those suggested by the Roundtable on Sustainable Palm Oil (RSPO). Further studies incorporating a site-specific case of palm oil systems would better illustrate the usefulness of the proposed guidelines.

Description: Purpose Environmental impacts of the decommissioning of nuclear power plants are brought into focus by the nuclear phase-out in Germany and a worldwide growing number of decommissioning projects. So far, life cycle assessments of decommissioning nuclear power plants have been conducted very rarely or are based on rather uncertain assumptions. Against this background, environmental impacts of the ongoing decommissioning of the nuclear power plant in Lubmin (KGR), Germany are examined. Methodological aspects like transferability to other decommissioning projects as well as influence of assumptions about the lifespan of a power plant are discussed. Methods A life cycle assessment of the decommissioning according to ISO 14040/44 is conducted. The decommissioning of one power plant (of the assessed KGR) is chosen as functional unit. The system boundaries include removal and demolition of plant components and buildings as well as decontamination, conditioning, interim storage, and final repository of low-level and interim-level nuclear waste together with disposal and recycling of conventional waste. Interim storage and final repository of high-level nuclear waste such as fuel rods are excluded from the system boundaries as they are assigned to the use phase of the plant. Primary data was obtained from the plant decommissioning firm (Energiewerke Nord GmbH, EWN) in Lubmin. The GaBi database was used to model background processes. Environmental impacts are estimated using the CML2001 methodology. Results and discussion Environmental impacts are mainly caused by on-site energetic demands of component removal and peripheral tasks. Further significant impacts are caused by the handling, storage, and final repository of low-level and intermediate-level nuclear waste. Recycling conventional, nonradioactive metallic waste has the potential to unburden the process in a significant scale, depending on recycling rates. Conclusions The dismantling of nuclear power plants shows a relevant environmental impact. Regarding the environmental impacts per kilowatt-hour assumptions concerning the plant’ lifespan are a crucial factor. Comparing the result from this study to recent datasets for nuclear power poses the question if LCA datasets represent environmental burdens of nuclear power accurately. The transferability of LCA results to other studies using one parameter for scaling is problematic and needs further research.

Description: Purpose This paper presents life cycle assessment of planned mass production of the thermal insulation blocks (TIB) made of thermal insulation composite material (TICM) from secondary raw materials—glass and plastic. This material is being developed at Brno University of Technology, Faculty of Civil Engineering for use in structural details of (especially low energy or passive) buildings subjected to higher compressive loads. Two production modes depending on the quality of the input materials are compared. Methods The assessment is conducted using GaBi 4 software tool with inbuilt Ecoinvent database. The results of the assessment are presented in individual impact categories according to used characterization model (CML 2001—Dec. 07). All the necessary energy and material flows are specified in detail for the purpose of the assessment. Cut-off allocation method is used for allocating the environmental impacts of recycled materials. Part of the assessment is sensitivity analysis of one variable parameter—amount of TIB produced per year. Results and discussion The results of the assessment show decisive impact of used electricity source on the overall results—86.2 and 94.3 %, respectively, for both production modes. This is closely connected with quality of used secondary raw materials and design of the production line. Use of higher-quality materials, as well as changes of the designed production line can reduce the overall environmental impacts by almost 30 %. Conclusions The results show possible improvements in the planned mass production of the TIB. They also find that further investigation will be required before the start of mass production, especially in connection with improving the environmental impacts of used electricity sources.

Description: Purpose The benefits and environmental burden of two different strategies (incineration vs anaerobic digestion followed by composting) to manage the organic fraction of municipal solid waste were assessed. Particular attention was also focused on system components, including collection, treatment, facility construction, and disposal, as well as the effect of the energetic context. Source segregation intensities considered for the scenario with incineration and with anaerobic digestion followed by composting were respectively of 0 and 52 %. Methods The analysis was performed by an LCA approach, and the impact was assessed by the CML method. The functional unit was a single ton of organic waste generated in the area considered. System boundaries were expanded to include the differences in waste collection and multi-functionality waste treatments. Existing databases were retrieved, also adopting experimental data for the waste management area considered. Results and discussion Overall, the scenario with the highest rate of source segregation of organic waste, using anaerobic digestion followed by composting, gave a lower impact for human and terrestrial toxicity. Concerning the other impacts, incineration gave the maximum benefits. The impact of anaerobic digestion and composting arises mainly from energy consumption, greenhouse gas emissions (i.e., N 2 O, VOC), and landfilling of residues. The sensitivity analysis performed by varying the energetic mix of the context confirmed the advantages of incineration of the organic fraction. Conclusions Incineration of organic waste leads to maximum environmental benefits compared to anaerobic digestion and composting. Furthermore, anaerobic digestion and composting was characterized by high gaseous emissions with high greenhouse gas potential even if the production of organic fertilizer gave some benefits concerning the avoided exploitation of mineral resources. The impact due to the collection phase and facility construction was quite limited and in some cases negligible.

Description: Purpose Most life cycle assessment (LCA) studies for flooring exclude the environmental and economic impacts incurred from the maintenance required due to uncertainty in average cleaning procedures, although some studies indicate that it may be the most significant component of the life cycle. This study investigates the impacts of maintenance on types of flooring and develops a single scoring system to compare floors based on both environmental and economic impacts. Methods The focus of this study was on the impact of maintenance on the life cycle of flooring choices. Maintenance data was collected from trade association studies and manufacturer’s recommendations. This data was compiled, along with data from previous flooring studies, to create a comprehensive life cycle inventory which was analyzed with the LCA software, SimaPro. A number of maintenance techniques and frequencies were tested in order to do a sensitivity analysis. An uncertainty analysis was completed using Monte Carlo simulations. A life cycle costing (LCC) analysis was used to evaluate the total present value cost of flooring including maintenance. Environmental and economic impacts were normalized to create a single score in order to compare the overall performance of flooring choices. Results and discussion Maintenance procedures may account for a significant portion of environmental and economic impacts of floorings. In the case of environmental scores, adding high maintenance to the life cycle can increase scores by anywhere from 31 % (hardwood) to 114 % (carpet). A sensitivity analysis of these scores shows that most of the score increase can be attributed to vacuuming. Maintenance costs considerably increase the total cost, accounting for 49 % of hardwood’s total cost and about 30 % of costs for linoleum, vinyl, and carpet. The expected service life of the home greatly influences which flooring is best, as costs and environmental scores change dynamically over time. For the expected service life of a home of 61 years, carpet has the worst and linoleum has the best overall performance. Conclusions Although averages for maintenance techniques are not currently known, ignoring maintenance as a part of the use phase presents a significant error in the comparison of flooring options environmentally and economically. Due in part to yearly maintenance effects, the flooring choice with the best overall performance changes dynamically depending on the expected service life remaining for the home.

Description: Purpose Polymers typically have intrinsic thermal conductivity much lower than other materials. Enhancement of this property may be obtained by the addition of conductive fillers. Nanofillers are preferred to traditional ones, due to their low percolation threshold resulting from their high aspect ratio. Beyond these considerations, it is imperative that the development of such new fillers takes place in a safe and sustainable manner. A conventional life cycle assessment (LCA) has been conducted on epoxy-based composites, filled with graphite nanoplatelets (GnP). In particular, this study focuses on energy requirements for the production of such composites, in order to stress environmental hot spots and primary energy of GnP production process (nano-wastes and nanoparticles emissions are not included). Methods A cradle-to-grave approach has been employed for this assessment, in an attributional modeling perspective. The data for the LCA have been gathered from both laboratory data and bibliographic references. A technical LCA software package, SimaPro (SimaPro 7.3), which contains Ecoinvent (2010) life cycle inventory (LCI) database, has been used for the life cycle impact assessment (LCIA), studying 13 mid-point indicators. Sensitivity and uncertainty analyses have also been performed. Results and discussion One kilogram of GnP filler requires 1,879 MJ of primary energy while the preparation of 1 kg of epoxy composite loaded with 0.058 kg of GnP 303 MJ. Besides energy consumption in the filler preparation, it is shown that the thermoset matrix material has also a non-negligible impact on the life cycle despite the use of GnP: the primary energy required to make epoxy resin is 187 MJ, i.e., 62 % of the total energy to make 1 kg of composite. Conclusions Raw material extraction and filler and resin preparation phase exhibit the highest environmental impact while the composite production is negligible. Thermosetting resin remains the highest primary energy demand when used as matrix for GnP fillers. The result of the sensitivity analysis carried out on the electricity mix used during the GnP and the composite production processes does not affect the conclusions.

Description: Purpose Nowadays, the intensive use of natural resources in order to satisfy the increasing energy demand suggests a threat to the implementation of the principles of sustainable development. The present study attempts to approach thermodynamically the depletion of natural resources in the methodological framework and the principles of life cycle assessment (LCA). Methods An environmental decision support tool is studied, the exergetic life cycle assessment (ELCA). It arises from the convergence of the LCA and exergy analysis (EA) methodologies and attempts to identify the exergetic parameters that are related to the life cycle of the examined system or process. The ELCA methodology, beside the fact that it locates the system parts which involve greater exergy losses, examines the depletion of natural resources (biotic and abiotic) and the sustainable prospective of the examined system or process, under the scope of exergy. In order to obtain concrete results, the ELCA methodology is applied to a large-scale, grid-connected, photovoltaic (PV) system with energy storage that is designed to entirely electrify the Greek island of Nisyros. Results and discussion Four discerned cases were studied that reflect the present state and the future development of the PV technology. The exergy flows and balance for the life cycle of the PV system, as they were formed in the ELCA study, showed that the incoming exergy (solar radiation, energy sources, and materials) is not efficiently utilized. The greater exergy losses appear at the stage of the operation of the PV installation. Due to the fact that contribution of the renewable exergy (solar radiation) to the formation of the total incoming exergy of Life Cycle is significant, it emerges that satisfaction of electric power needs with a PV system appears to be exergetic sustainable. The increase of the Life Cycle exergetic efficiency supported by the future technological scenario in contrast to present scenarios emerges from the increased electricity output of the PV system. Consequently, the increased exergetic efficiency involves decreased irreversibility (exergy losses) of the PV system’s life cycle. Conclusions The application of ELCA in electricity production technologies exceeds the proven sustainable prospective of the PV systems; however, it aims to show the essence of the application of ELCA methodology in the environmental decision making process. ELCA can be a useful tool for the support and formation of the environmental decision making that can illustrate in terms of exergetic sustainability the examined energy system or process.

Description: Purpose Ordinary product LCA studies focus on measuring or minimizing environmental impact, but do not address if the product fits in a sustainable consumption pattern. This paper proposes a setup in which the planetary boundaries define the maximum impact, and the minimum requirements for a reasonable consumption level specify a lower impact level. Thus, a “safe operating space” remains. Methods We use an IO table for EU-27 and the consumption pattern of the Bulgarian population extrapolated to the EU level as driving climate impact. The EU’s policy targets are used as a planetary boundary for climate change. Results The 2020 target is shown to be able to accommodate the Bulgarian-style consumption, with room for a much higher GDP. The 2050 target, however, is too narrow, and a slightly smaller consumption pattern is needed to reach the target. Conclusions Although the approach is highly simplified and neglects many developments, the idea of using IO-tables and minimum consumption levels to backcast directions to be taken is expected to help policymakers. We acknowledge some important limitations of our approach, but accept these in the context of exploring future scenarios and how to get there, instead of predicting the future.

Description: Purpose In the USA, several studies have been conducted to analyze the energy consumption and atmospheric emissions of Warm-mix Asphalt (WMA) pavements. However, the direct and indirect environmental, economic, and social impacts, termed as Triple-Bottom-Line (TBL), were not addressed sufficiently. Hence, the aim of this study is to develop TBL-oriented sustainability assessment model to evaluate the environmental and socio-economic impacts of pavements constructed with different types of WMA mixtures and compare them to a conventional Hot-mix Asphalt (HMA). The types of WMA technologies investigated in this research include Asphamin® WMA, Evotherm™ WMA, and Sasobit® WMA. Methods To achieve this goal, supply and use tables published by the U.S. Bureau of Economic Analysis were merged with 16 macro-level sustainability metrics. A hybrid TBL-LCA model was built to evaluate the life-cycle sustainability performance of using WMA technologies in construction of asphalt pavements. The impacts on the sustainability were calculated in terms of socio-economic (import, income, gross operating surplus, government tax, work-related injuries, and employment) and environmental (water withdrawal, energy use, carbon footprint, hazardous waste generation, toxic releases into air, and land use). A stochastic compromise programming model was then developed for finding the optimal allocation of different pavement types for the U.S. highways. Results and discussion WMAs did not perform better in terms of environmental impacts compared to HMA. Asphamin® WMA was found to have the highest environmental and socio-economic impacts compared to other pavement types. Material extractions and processing phase had the highest contribution to all environmental impact indicators that shows the importance of cleaner production strategies for pavement materials. Based on stochastic compromised programming results, in a balanced weighting situation, Sasobit® WMA had the highest percentage of allocation (61 %); while only socio-economic aspects matter, Asphamin® WMA had the largest share (57 %) among the asphalt pavements. The optimization results also supported the significance of an increased WMA use in the U.S. highways. Conclusions This research complemented previous LCA studies by evaluating pavements not only from environmental emissions and energy consumption standpoint, but also from socio-economic perspectives. Multi-objective optimization results also provided important insights for decision makers when finding the optimum allocation of pavement alternatives based on different environmental and socio-economic priorities. Consequently, this study aimed to increase awareness of the inherent benefits of economic input–output analysis and multi-criteria decision making through application to emerging sustainable pavement practices.

Description: Purpose In this article, we present an innovative way of deriving comparable functional systems for comparative life cycle assessments (LCAs) of food products. We define the functional unit as the contribution of one or more foods to the nutrient composition of a weekly diet and, after a product substitution, employ a product system expansion approach to search for an alternative set of products which provides an equivalent nutritional composition. Methods Replacement is regarded within the context of a weekly diet. The comparable diet is a solution to a linear problem which finds the diet that is most similar to the starting one, subject to nutritional and/or other constraints that guarantee a minimum dietary quality. The formulation gives priority to selecting food products according to popularity. Results We illustrate our method with two examples. We show that a baseline diet containing 3.6 servings of apples a week is equivalent to a similar diet in which the apples are replaced with 3.6 servings of oranges and servings of strawberry and kiwi are removed. These changes are necessary mainly because of differences in the vitamin C content between apples and oranges. The second example is a replacement of all meat in a weekly diet by a soy-based meat substitute. In this case, additional fish products need to be consumed to make up for a lack of selenium and essential amino acids. Conclusions We present an innovative and objective way to overcome the challenge of comparing two or more food products in a comparative LCA. Our approach is systematic and finds the alternative diet that best meets the nutritional criteria as well as reflecting the food preferences of the population. The method selects products according to the role they play in the dietary pattern. Moreover, the method is flexible enough to allow for different selection criteria and other nutritional and non-nutritional constraints.

Description: Purpose The aim of this work is to propose an objective method for evaluating subcategories in social life cycle impact assessment (S-LCIA). Methods for assessing subcategories have been available since 2006, but a number of these either fail to include all the subcategories envisaged in the guidelines for S-LCA (UNEP/SETAC 2009 ) or are subjective in their assessment of each subcategory. Methods The methodology is characterized by four steps: (i) the use of the organization as unit process, in which it was decided to assess the social profile of the organization responsible for the processes involved in the product life cycle, (ii) definition of the basic requirement to assess each subcategory, (iii) definition of levels based on the environment context or organizational practice and the data availability and (iv) assignment of a quantitative value. Results and discussion The result of the method applied was the development of the subcategory assessment method (SAM). SAM is a characterization model that evaluates subcategories during the impact assessment phase. This method is based on the behaviour of organizations responsible for the processes along the product life cycle, thereby enabling a social performance evaluation. The method, thus, presents levels for each subcategory assessment. Level A indicates that the organization exhibits proactive behaviour by promoting basic requirement (BR) practices along the value chain. Level B means that the organization fulfils the BR. Levels C and D are assigned to organizations that do not meet the BR and are differentiated by their context. The greatest difficulty when developing SAM was the definition of the BR to be used in the evaluation of the subcategories, though many indications were present in the methodological sheets. Conclusions SAM makes it possible to go from inventory to subcategory assessment. The method supports evaluation across life cycle products, thereby ensuring a more objective evaluation of the social behaviour of organizations and applicable in different countries. Recommendations When using SAM, it is advisable to update the data for the context environment. The method might be improved by using data for the social context that would consider not only the country, but also the region, sector and product concerned. A further improvement could be a subdivision of the levels to better encompass differences between organizations. It is advisable to test SAM by applying it to a case study.

Description: Purpose Ceramic tiles play a strategic role in the Italian market; currently, the Italian production is of 367.2 million m 2 (Confindustria Ceramica 2012 ). In 2009, Italy was positioned as the world’s fourth largest producer of ceramic tiles, producing 368 million m 2 of the world’s total production of 1,735 million m 2 Giacomini (Ceram World Rev 88:52–68, 2010 ). Therefore, there is an ongoing effort to create innovations in the products offered and their manufacturing processes, in order to better compete on the market and to create eco-friendly products. Recently, the Italian Ceramic District has increased its focus on environmental issues with the aim of protecting natural resources and reducing the energy and material consumption. For this reason, a new product was born in the Italian Ceramic District, namely, a large thin ceramic tile (dimensions 1,000 mm × 3,000 mm × 3.5 mm) reinforced with a fibreglass backing, which gives the product excellent resistance and flexibility properties. The aim was to manufacture a new product with lower environmental impact than the traditional one. The production of a large thin ceramic tile requires, in fact, a lower quantity of materials, transports and energy consumptions comparing to the same metres square of traditional ceramic tile. At the present, no comparative life cycle assessment (LCA) studies have been performed between traditional and innovative ceramic stoneware tiles. This study analyses, for the first time, a life cycle of the innovative ceramic product (porcelain stoneware) developed by a company of the Italian Ceramic District. Methods The analysis is performed using the LCA methodology, in order to identify environmental impacts, energy consumption and CO 2 equivalent emissions that occur during extraction of raw materials, transportation, production, material handling, distribution and end-of-life stages within a cradle to grave perspective. Results and conclusions LCA analysis indicates that the highest environmental impact mainly affects the respiratory inorganics impact category due to base slip production (27.62 %), caused by the transport of the raw materials and by non-renewable impact category due to both the pasting phase (21.31 %) and the two-component adhesive manufacture. The major greenhouse gas (GHG) emissions are related to the production of polyurethane, a component of the adhesive used in the pasting stage, and to the natural gas consumption in the firing process.

Description: Purpose Conventional wisdom suggests that product reuse can provide environmental savings. The purpose of this study is to first compare the environmental impacts of retail refilling and remanufactured inkjet cartridge alternatives to production of new inkjet cartridges, and then determine the extent to which consumer behavior can influence life cycle outcomes. Methods A life cycle inventory was developed for an inkjet cartridge with an integral print head using material composition data collected from cartridge disassembly and material processing, product manufacturing, and transportation inputs estimated from market data and the ecoinvent database in SimaPro 7.3. Although previous comparative life cycle assessment (LCA) studies for printer cartridges typically use “pages printed” or a variation thereof for the functional unit, “cartridge use cycles” is more suitable for examining reused inkjet cartridge alternatives that depend on the inkjet cartridge end-of-life (EOL) route chosen by the consumer. Since multiple reuse cycles achieved from refilling by a retailer was of specific interest, a functional unit defined in the form of “five use cycles” included the mode and manner in which consumers purchased inkjet cartridge use cycles. Results and discussion Cartridge refills present the lowest environmental impact, offering a 76 % savings in global warming potential (GWP) impact compared to production and purchase of a new inkjet cartridge alternative, followed by the remanufacturing case, which provided a 36 % savings in GWP impact compared to the new inkjet cartridge. However, results varied widely, even switching to favor new cartridge purchase, depending on how consumer transport was modeled, specifically the mode of travel, travel patterns (number of trips), and method of allocating impact to each trip. Conclusions Refilling an original equipment manufacturer (OEM) cartridge four consecutive times provides the best alternative for reducing environmental impact for those consumers that purchase inkjet cartridges one at a time. On the other hand, consumers that purchase multiple cartridges in a single trip to a retailer reduce environmental impact more by transport minimization than by refilling. Results reinforce the need for more comprehensive inclusion of consumer behavior when modeling life cycle environmental impact of product alternatives.

Description: Purpose The emission of greenhouse gases (GHG) is a key criterion in the environmental assessment of biofuels. Life cycle inventories taking into account the latest methodological developments are an essential prerequisite for this assessment. In the last years, substantial progresses in the modelling of nitrogen emissions relevant for the climate as well as in modelling the emissions from land use change (LUC) have been achieved. Therefore, the biomass production inventories in the ecoinvent database were revised to take into account these developments. Methods The IPCC method tier 1 has been used for the assessment of N 2 O emissions. Induced emissions from NH 3 and NO 3 were included as well. Due to the importance of the latter emissions for N 2 O formation, these emissions have also been updated and harmonised. The Agrammon model was used for the NH 3 emissions. The SALCA-NO 3 model has been applied in the European inventories to estimate nitrate leaching, whilst in non-European inventories the SQCB-NO 3 model has been used. The quantification of the land use change areas has been based on annualized, retrospective data of the last 20 years. All carbon pools (from aboveground biomass to soil organic carbon) were considered and differentiated on a regional level for all of the natural vegetation categories affected. Whenever possible, default values and methods from the IPCC 2006 were applied. Results and discussion The changes for ammonia emissions were generally very small (−5 % on average). The nitrate emissions increased on average by +13 %, but this slight trend is the result of important downward and upward changes, whilst the average N 2 O emissions decreased by −26 %. For the existing inventories of soybean, palm oil and sugarcane production, significant increases of GHG emissions resulted from LUC modelling. This was mainly due to the consistent inclusion of all carbon stocks according to the IPCC guidelines. The calculation method can also result in important C sequestration effects in certain cases like African Jatropha production. Conclusions The changes in greenhouse gas emissions due to the updated methodology were significant. This shows that life cycle assessment studies for biofuels using older methodological bases need to be revised and could lead to different conclusions. The implemented and cultivated superstructure for LUC modelling is modular and flexible and can be easily extended to other important crop activities. The new parameterisation functionality applied for the activities provides powerful means for the simple generation of site-specific activities.