Integration of life cycle assessment and life cycle costing for the eco-design of rubber products

Rubber hoses are a category of rubber products that are widely and intensively employed in construction sites for concrete conveying. There has been lack of study to investigate the life cycle environmental and economic impacts of the rubber hoses as an industrial product. In this study, we analyze four types of rubber hoses with the inner layer made of different rubber composites to resist abrasion, i.e., Baseline, S-I, S-II and S-III. Tests of the wear resistance are carried out in the laboratory and S-III shows high abrasion resisting performance with the concrete conveying volume up to 20,000 m3 during the service life. Life cycle assessment (LCA) and life cycle costing (LCC) models are established for evaluating the four types of rubber hoses. A target function is developed to integrate LCA and LCC by converting the LCA results to the environmental costs. It is found that S-III can save 13% total cost comparing to Baseline. The production stage is the largest contributor to the environmental single score, while the use stage is the largest contributor to the life cycle cost. Sensitivity analyses are conducted and the results of this study are validated with the previous studies. The integrated method of LCA and LCC developed in this study paves a way for the eco-design of industrial rubber hoses and is potentially applicable to other rubber products.

Whole building life cycle assessment at the design stage: a BIM-based framework using environmental product declaration

PurposeWhole building life cycle assessment (WBLCA) is a key methodology to reduce the environmental impacts in the building sector. Research studies usually face challenges in presenting comprehensive LCA results due to the complexity of assessments at the building level. There is a dearth of methods for the systematic evaluation and optimization of the WBLCA performance at the design stage. The study aims to develop a design optimization framework based on the proposed WBLCA method to evaluate and improve the environmental performance at the building level.Design/methodology/approachThe WBLCA development method is proposed with detailed processes based on the EN 15978 standard. The environmental product declaration (EPD) methods were adopted to ensure the WBLCA is comprehensive and reliable. Building information modeling (BIM) was used to ensure the building materials and assembly contributions are accurate and provide dynamic material updates for the design optimization framework. Furthermore, the interactive BIM-LCA calculation processes were demonstrated for measuring the environmental impacts of design upgrades. The TOPSIS-based LCA results normalization was selected to conduct the comparisons of various building design upgrades.FindingsThe case study conducted for a residential building showed that the material embodied impacts and the operational energy use impacts are the two critical factors that contribute 60–90% of the total environmental impacts and resource uses. Concrete and wood are the main material types accounting for an average of 65% of the material embodied impacts. The air and water heating for the house are the main energy factors, as these account for over 80% of the operational energy use. Based on the original WBLCA results, two scenarios were established to improve building performance through the design optimization framework.Originality/valueThe LCA results show that the two upgraded building designs create an average of 5% reduction compared with the original building design and improving the thermal performance of the house with more insulation materials does not always reduce the WBLCA results. The proposed WBLCA method can be used to compare the building-level environmental performances with the similar building types. The proposed framework can be used to support building designers to effectively improve the WBLCA performance.

The Potential of Al2O3–ZrO2-Based Composites, Formed via CSC Method, in Linear Infrastructure Applications Based on Their Mechanical, Thermal and Environmental performance

Ceramic-ceramic composites have been prepared using the centrifugal slip casting method (CSC). The method has so far been mainly utilized in making ceramic-metal composites. Al2O3–ZrO2 composites have been obtained with different shares of ZrO2, i.e., 15, 50 and 75 vol pct, respectively. Prior to sintering the composite samples, the rheological properties of the casting slips were investigated and thermogravimetric tests were performed. Upon sintering, all three series of the ceramic composites showed a density close to 100 pct and no microcracks or delamination. Phase, microstructural and mechanical investigations were carried out to determine what effect the share of ceramics has on the composites produced. An increase in the share of ZrO2 in the Al2O3–ZrO2 composite leads to a reduction in the growth of Al2O3 grains and a decrease in the average hardness. Cross-sectional hardness testing of the composites showed no evident gradient in any of the samples. Life cycle analysis (LCA) results indicate that the further optimization of the composite formation process, including up-scaling, allows to obtain Al2O3–ZrO2-based pipes possessing more favorable environmental characteristics compared with materials conventionally used for linear infrastructure, which is important in light of the global transformation toward sustainable construction and the circular economy. Graphical abstract

lca_algebraic: a library bringing symbolic calculus to LCA for comprehensive sensitivity analysis

Purpose In this paper, we present new tools to ease the analysis of the effect of variability and uncertainty on life cycle assessment (LCA) results. Methods The tools consist of a standard protocol and an open-source library: lca_algebraic. This library, written in Python and based on the framework Brightway2 (Mutel in J Open Source Softw 2(12):236, 2017) provides functions to support sensitivity analysis by bringing symbolic calculus to LCA. The use of symbolic calculus eases the definition of parametric inventories and enables a very fast evaluation of impacts by factorizing the background activities. Thanks to this processing speed, a large number of Monte Carlo simulations can be generated to evaluate the variation of the impacts and apply advanced statistic tools such as Sobol indices to quantify the contribution of each parameter to the final variance (Sobol in Math Comput Simul 55(1–3):271–280, 2001). An additional algorithm uses the key parameters, identified from their high Sobol indices, to generate simplified arithmetic models for fast estimates of LCA results. Results and discussion The protocol and library were validated through their application to the assessment of impacts of mono crystalline photovoltaic (PV) systems. A comprehensive sensitivity analysis was performed based on the protocol and the complementary functions provided by lca_algebraic. The proposed tools helped building a detailed parametric reference LCA model of the PV system to identify the range of variation of multi-criterion LCA results and the key foreground-related parameters explaining these variations. Based on these key parameters, we generated simplified arithmetic models for quick and simple multi-criteria environmental assessments to be used by non-expert LCA users. The resulting models are both compact and aligned with the reference parametric LCA model of crystalline silicon PV systems. Conclusion This work brings powerful and practical tools to the LCA community to better understand, identify, and quantify the sources of variation of environmental impacts and produce simplified models to spread the use of LCA among non-experts. The library mainly explores the uncertainties of the foreground activities. Further work could also integrate the uncertainty of background activities, described, for example, by pedigree matrices.

Step-by-step social life cycle assessment framework: a participatory approach for the identification and prioritization of impact subcategories applied to mobility scenarios

Purpose Investigating potential social and socio-economic impacts should play a key role for the development of sustainable mobility alternatives. Social life cycle assessment (S-LCA) is becoming increasingly important to ensure holistic sustainability assessments. The present work aims at identifying and evaluating social and socio-economic impact subcategories in S-LCA. A novel participatory approach implying all concerned stakeholders is proposed to select relevant impact subcategories and thus contribute to a thorough interpretation of S-LCA results. It is applied to assess electric and conventional vehicles. Methodology This paper describes a comprehensive step-by-step S-LCA framework. The innovation of this work consists in defining a structured S-LCA framework integrating a systematic approach based on two stages: (1) a sectorial risk analysis for the identification of impact subcategories and (2) a participatory approach for their prioritization. The proposed participatory approach considers all concerned stakeholders to enable the selection of the most relevant impact subcategories. A set of social inventory indicators is attributed to subcategories that were perceived as the most relevant. These are used to perform the social evaluation and carry out a full analysis in the result interpretation allowing thus to integrate a multi-actor perspective to the materiality assessment. Results The defined S-LCA framework is implemented to compare two mobility scenarios, corresponding to electric and conventional vehicle technologies. A new set of mobility-related impact subcategories is proposed for users’ stakeholder. Following the new designed participatory approach, subcategories for all stakeholders are prioritized according to different actors’ perceptions. For example, “safe and healthy living conditions,” “local employment,” and “delocalization and migration” were perceived for local communities as the most relevant subcategories by the different consulted stakeholders (industrial, academic, and public actors and users). These results also showed that social significance varies depending on the consulted actors and on the geographical area of the study. Using PSILCA database, we have investigated the subcategories that were perceived as the most relevant. Results for the evaluation and interpretation phases are presented for both transportation technologies. Conclusions This approach aims at increasing local relevance of S-LCA results and their representativeness. Results for the considered mobility scenarios have demonstrated the need to extend the scope of the materiality assessment, generally used for determining subcategories’ social significance from a single stakeholder perspective, by involving other stakeholders into the prioritization stage. Moreover, the proposed comprehensive S-LCA framework integrating the participatory approach is general enough to be applied to other product systems and sectors.

Environmental Sustainability Assessment of Pig Farms in Selected European Countries: Combining LCA and Key Performance Indicators for Biodiversity Assessment

The aim of this study was to combine Life Cycle Assessment (LCA) with a Key Performance Indicator (KPI) assessment focusing on biodiversity in order to examine the environmental impacts of different pig farm types (13 breeding, 23 finishing and 27 breeding-to-finishing farms) in seven European countries. In addition, the relationship between environmental impacts and selected farm management characteristics was explored. Fossil energy depletion (FED), global warming (GWP), acidification (AP) as well as marine (MEP) and fresh water (FEP) eutrophication potential were assessed by an attributional LCA and expressed per kilogram body mass net sold (BMNS). In addition, the potential biodiversity performance of all crop-livestock farms within the sample (n = 56) was evaluated with a KPI assessment of biodiversity-related field management characteristics. We found no relationship between LCA results and biodiversity scores (KPI). LCA and biodiversity performance varied more within than across farm types (breeding, finishing, breeding-to-finishing). For example, the GWP expressed per kg BMNS of the breeding unit of breeding-to-finishing farms was on average (median) 2.77 (range: 1.40–4.78) and of breeding farms 2.57 (range: 1.91–3.23) kg CO2-eq. The average (median) biodiversity theme score for breeding farms was 51% (range: 36–70%), for breeding-to-finishing farms 38% (range: 30–68%) and for finishing farms 43% (range: 28–67%). Several farm management characteristics (e.g. FCR, productivity, proportion of solid manure) correlated with all/some LCA results. Biodiversity performance depended especially on KPIs related to ecological focus areas, fertiliser management and GMO crops. The large range regarding environmental performance in both LCA and KPI assessment across farm types indicates that farm-specific improvement measures should be implemented to enhance overall environmental sustainability on farm. In conclusion, combining LCA with KPI assessment provides a more comprehensive environmental impact assessment of pig farms.

Comparative Life Cycle Analysis of Hybrid and Conventional Drive Vehicles in Various Driving Conditions

Growing environmental concern prompts vehicle users to search for cleaner and ecological transport modes. Many consumers and organizations have decided to replace conventional diesel or gasoline powered vehicles with alternative drive or alternative-powered vehicles. Operating conditions may have a heavy influence on the operating parameters of vehicles, such as: airpollution emission, energy consumption and fuel consumption. This paper presents a comparative analysis of the life cycle of conventional and hybrid drive vehicles in various driving conditions. The presented LCA results show that replacing a conventional diesel or gasoline vehicle with a hybrid electric drive vehicle results in approximately 40 % lower total lifetime air-pollutant emissions than those of conventional drive vehicles in urban driving conditions.

Making the use of scenarios in LCA easier: the superstructure approach

Purpose Much progress has recently been made in modelling future background systems for LCA by including future scenario data, e.g. from Integrated Assessment Models (IAMs), into life cycle inventory (LCI) databases. A key problem is, however, that this yields potentially dozens of scenario LCI databases (i.e. LCI databases that represent different scenarios and reference years), instead of a single background database, which is very impractical for LCA modelling purposes. This paper proposes an approach to overcome this problem. Methods The approach consists of transforming all scenario LCI databases into a single superstructure database and an associated scenario difference file. The superstructure database is also a regular LCI database, but is constructed to contain all unique exchanges (elementary and intermediate flows) and processes that exist across all scenario LCI databases. The scenario difference file stores the differences between all scenarios and can be used to turn the superstructure into a specific scenario LCI database. This is very fast as it can be done in memory during LCA calculations. Results and discussion A key advantage of the superstructure approach is that a single LCI database can be used to represent different background systems. Therefore, the practitioner does not need to re-link a foreground system to multiple LCI databases, which is work-intensive and invites modelling errors. LCA results for all scenarios and reference years can be calculated automatically. We also illustrate how the superstructure approach has been implemented in the Activity Browser open source LCA software. Although this paper introduces the superstructure approach for background scenarios, it can also be used to model foreground scenarios, and even, as implemented in the Activity Browser, combinations of background and foreground scenarios. Finally, we briefly discuss further challenges that need to be addressed for a more widespread use of background scenarios in LCA. Conclusions The superstructure approach presents a practical solution for making the use of future background scenarios more wide-spread and, therefore, to overcome the problem of performing prospective LCA with temporally inconsistent foreground and background systems. The implementation in the Activity Browser makes the approach available for anyone and may serve as inspiration for other LCA software to implement the superstructure approach or a similar concept. While this may be an important technical milestone, additional coordination between data providers, scenario generators, LCA practitioners, and software developers will be required to further facilitate the use of background scenarios in prospective LCA studies.

Are consumers aware of products’ environmental impacts? Different results between life cycle assessment data and consumers’ opinions: the case study of organic Parmigiano Reggiano and its packaging

Companies are paying attention to the reduction of their products’ environmental impact and consumer’s opinion is fundamental to understand which are the market strategies to be undertaken. Consumers are interested in environmental issue, but do they buy products taking scientific data into account? For example, according to literature, consumers believe that the abolition of plastic packaging is the solution to marine litter caused by plastic waste, but researchers and scientists do not agree. In collaboration with an Italian dairy factory, this study carried out a survey to understand what is the eco-friendliest packaging materials according to consumers, taking as a reference the Parmigiano Reggiano. Their opinions were then compared to the Life Cycle Assessment (LCA) results obtained considering the whole cheese life cycle and its packaging. The analysis highlights a big gap between consumers’ thoughts and scientific data and suggests solutions to make citizens aware of real environmental impacts.

Developing Conversion Factors of LCIA Methods for Comparison of LCA Results in the Construction Sector

The inconsistency caused by different life cycle impact assessment (LCIA) methods is a long-term challenge for the life cycle assessment (LCA) community. It is necessary to systematically analyze the differences caused by LCIA methods and facilitate the fair comparison of LCA results. This study proposes an effective method of conversion factors (CFs) for converting the results of 8 LCIA methods for 14 impact categories and then demonstrates its application in the construction sector. Correlation analyses of the datasets of construction materials are conducted to develop CFs for the impact categories. A set of conversion cards are devised to present the CFs and the associated correlation information for the LCIA methods. It is revealed that the differences between LCIA methods are largely caused by the characterization methods, rather than due to the metrics. A comparison based only on the same metrics but ignoring the underlying LCIA mechanisms is misleading. High correlations are observed for the impact categories of climate change, acidification, eutrophication, and resource depletion. The developed CFs and conversion cards can greatly help LCA practitioners in the fair comparison of LCA results from different LCIA methods. Case studies are conducted, and verify that by applying the CFs the seemingly incomparable results from different LCIA methods become comparable. The CF method addresses the inconsistency problem of LCIA methods in a practical manner and helps improve the comparability and reliability of LCA studies in the construction sector. Suggestions are provided for the further development of LCIA conversion factors.