Multi-actor multi-criteria sustainability assessment framework for energy and industrial systems in life cycle perspective under uncertainties. Part 2: improved extension theory

Purpose

The concept of sustainability and sustainable development has been widely incorporated in energy and industrial systems. This paper is the second part of a two-paper series dealing with multi-actor multi-criteria sustainability assessment of alternative energy and industrial systems in life cycle perspective under uncertainties.

Methods

The criteria system including four macroscopic aspects (environmental, safety, social and economic aspects) has been developed for sustainability assessment of energy and industrial systems. An improved extension theory which can address interval decision-making matrix has been developed for determining the sustainability degree of the energy and industrial systems.

Results and discussion

The weights of the criteria for sustainability assessment are the first part of the two-paper series. An illustrative case has been studied by the proposed multi-criteria decision-making method, and the sustainability of six alternative options for the production of a 1-t product was investigated. The sustainability degree of these six alternative options can be determined by the proposed method.

Conclusions and perspectives

A methodology for multi-actor multi-criteria sustainability assessment of energy and industrial options has been developed in this study, the traditional extension theory has been modified to deal with the uncertainty problems and the proposed method can rank the alternative energy and industrial systems with the decision-making matrix in which the data of the alternatives with respect to the evaluation criteria are intervals. In the improved extension theory, sustainability has been dived into five grades: excellent, good, satisfied, barely adequate and fail. According to the method for calculating the weights of the criteria for sustainability assessment proposed in part 1, these weights were used to calculate the integrated dependent degree which is a measure of what degree an alternative belongs to the classical fields. An optimal programming model for maximizing the satisfied degree has been developed to rank the sustainability sequence of the alternative options and determine the sustainability degree of each alternative.

     

The application of life cycle assessment to public policy development

Purpose

Despite the potential value it offers, integration of life cycle assessment (LCA) into the development of environmental public policy has been limited. This paper researches potential barriers that may be limiting the use of LCA in public policy development, and considers process opportunities to increase this application.

Methods

Research presented in this paper is primarily derived from reviews of existing literature and case studies, as well as interviews with key public policy officials with LCA experience. Direct experience of the author in LCA projects with public policy elements has also contributed to approaches and conclusions.

Results and discussion

LCAs have historically been applied within a rational framework, with experts conducting the analysis and presenting results to decision-makers for application to public policy development. This segmented approach has resulted in limited incorporation of LCA results or even a broader approach of life cycle thinking within the public policy development process. Barriers that limit the application of LCA within the public policy development process range from lack of technical knowledge and LCA understanding on the part of policy makers, to a lack of trust in LCA process and results. Many of the identified barriers suggest that the failure of LCAs to contribute positively to public policy development is due to the process within which the LCA is being incorporated, rather than technical problems in the LCA itself. Overcoming the barriers to effective use of LCAs in public policy development will require a more normative approach to the LCA process that incorporates a broad group of stakeholders at all stages of the assessment. Specifically, a set of recommendations have been developed to produce a more inclusive and effective process.

Conclusions

In an effort to effectively incorporate LCA within the overall public policy decision-making process, the decision-making process should incorporate a multi-disciplinary approach that includes a range of stakeholders and public policy decision-makers in a collaborative process. One of the most important aspects of incorporating LCA into public policy decisions is to encourage life cycle thinking among policy makers. Considering the life cycle implications will result in more informed and thoughtful decisions, even if a full LCA is not undertaken.

     

Development of social sustainability assessment method and a comparative case study on assessing recycled construction materials

Purpose

Sustainability analysis should include the assessment of the environmental, social, and economic impacts throughout the life cycle of a product. However, the social sustainability performance assessment is seldom carried out during materials selection due to its complex nature and the lack of a social life cycle assessment tool. This study presents a single score-based social life cycle assessment methodology, namely social sustainability grading model, for assessing and comparing the social sustainability performance of construction materials using a case study on recycled and natural construction materials.

Methods

The proposed method is developed based on the methodological framework provided by the United Nations Environment Programme/Society of Environmental Toxicology and Chemistry guidelines published in 2009 and the methodological sheets published in 2013, the indicators and sustainability reporting guidelines provided by the Global Reporting Initiatives and ISO 26000 for social responsibility of products, and the indicators provided by the Hong Kong Business Environment Council Limited for construction sustainability. A twofold research approach is proposed in this model: the first one is the qualitative research based on expert interviews to identify, select, and prioritize the relevant subcategories and indicators, and the second one is the operational research based on the case-specific survey to collect the required data. A social sustainability index was proposed for the interpretation of the results effectively. A case study on construction materials was conducted to illustrate the implementation of the method using case-specific first-hand data.

Results and discussion

The major outcome of this study is the systematic development of a social sustainability assessment tool based on the established standards and guidelines. The case study showed that four subcategories are crucial social concerns for construction materials (i.e., health and safety issues of the materials, health and safety of workers, company’s commitment to sustainability, and company’s policies on energy and water consumption). Based on the sustainability index proposed, using recycled aggregates from locally generated waste materials scored higher (about 31–34%) social sustainability than using imported natural aggregates. In addition, recycled aggregates and natural aggregates achieved “sustainable” and “neutral” rating sustainability levels, respectively. However, several subcategories (e.g., health and safety, working hour, forced work, training and social benefits of workers, and quality of the materials and information disclosing to public) are still needed to improve the social sustainability performance of recycled aggregates.

Conclusions

An integrated social life cycle assessment method is presented in this study for assessing the social sustainability of construction materials. In addition, the reported case study in this paper is one of the first attempts for social sustainability assessment of recycled construction materials, and the method can be applied to other recycled materials/products for comparative analysis. However, several critical factors, such as integration in other life cycle methods and software, sensitivity analysis, and more case studies, are still needed for further improvement of the developed method.

     

A modeling framework to evaluate sustainability of building construction based on LCSA

Purpose

Life cycle sustainability assessment (LCSA) is a method that combines three life cycle techniques, viz. environmental life cycle assessment (LCA), life cycle costing (LCC), and social life cycle assessment (S-LCA). This study is intended to develop a LCSA framework and a case study of LCSA for building construction projects.

Methods

A LCSA framework is proposed to combine the three life cycle techniques. In the modeling phases, three life cycle models are used in the LCSA framework, namely the environmental model of construction (EMoC), cost model of construction (CMoC), and social-impact model of construction (SMoC). A residential building project is applied to the proposed LCSA framework from “cradle to the end of construction” processes to unveil the limitations and future research needs of the LCSA framework.

Results and discussion

It is found that material extraction and manufacturing account for over 90 % to the environmental impacts while they contribute to 61 % to the construction cost. In terms of social impacts, on-site construction performs better than material extraction and manufacturing, and on-site construction has larger contributions to the positive social impacts. The model outcomes are validated through interviews with local experts in Hong Kong. The result indicates that the performance of the models is generally satisfactory.

Conclusions

The case study has confirmed that LCSA is feasible. Being one of the first applications of LCSA on building construction, this study fulfills the current research gap and paves the way for future development of LCSA.

     

Social life cycle assessment of first and second-generation ethanol production technologies in Brazil

Purpose

The main goal of this study is to suggest quantitative social metrics to evaluate different sugarcane biorefinery systems in Brazil by exploring a novel hybrid approach integrating social life cycle assessment and input-output analysis.

Methods

Social life cycle assessment is the main methodology for evaluating social aspects based on a life-cycle approach. Using this framework, a hybrid model integrating social life cycle assessment and input-output analysis was introduced to evaluate different social effects of biorefinery scenarios considering workers as the stakeholder category. Job creation, occupational accidents, wage profile, education profile, and gender profile were selected as the main inventory indicators. A case study of three scenarios considering variations in agricultural and industrial technologies (including sugarcane straw recovery and second-generation ethanol production, for instance) was carried out for evaluating present first-generation (1G-basic, 1G-optimized) and future first- and second-generation ethanol production (1G2G).

Results and discussion

The 1G-basic scenario leads to higher job creation levels over the supply chain mainly because of the influence of agricultural stage whose workers are mostly employed in sugarcane manual operations. On the other hand, 1G-optimized and 1G2G present supply chains are more reliant on the manufacturing, trade, and services sectors whose workers are associated with a lower level of occupational accidents, higher average wages, higher education level, and more participation of women in the work force.

Conclusions

The use of a novel hybrid approach integrating social life cycle assessment (SLCA) and input-output analysis (IOA) was useful to quantitatively distinguish the social effects over different present and future sugarcane biorefinery supply chains. As a consequence, this approach is very useful to support decision-making processes aiming to improve the sustainability of sugarcane biorefineries taking social aspects into account.

     

An analytic framework for social life cycle impact assessment—part 1: methodology

Purpose

This study aims to develop a new framework of social life cycle impact assessment (SLCIA) method based on the United Nations Environment Program/Society of Environmental Toxicology and Chemistry (UNEP/SETAC) Guidelines for analyzing the social impact in Taiwan, particularly in the electronics industry.

Methods

After reviewing the literature on social life cycle assessment (SLCA), we analyzed existing case studies and developed SLCIA methods based on the UNEP/SETAC Guidelines. We thereafter identified stakeholders, subcategories, and indicators in accordance with the current status of SLCA case studies and opinions from ten experts in the Taiwanese electronics industry. Both quantitative and semi-quantitative indicators were subsequently proposed to assess the social impact of workers in the Taiwanese electronics sector. Each indicator was given the score of 1 to 5 by classifying the social impact percentage of nine scales. To formulate an analytic framework for SLCIA, the weighting values of each subcategory and indicator were determined using the consistent fuzzy preference relations (CFPR) method.

Results and discussion

Seven subcategories and 19 qualitative and quantitative indicators of worker stakeholders for the electronics sector were identified based on the UNEP/SETAC Guidelines. A score of 1 to 5 is assigned to each quantitative indicator by classifying the social impact percentage of nine scales. The data obtained from companies for each quantitative indicator were subsequently transformed into social impact percentage in terms of the statistical data on social situations at the country or industry level. With regard to semi-quantitative indicators, three implementation levels of management efforts on social performance within five elements were identified. The CFPR method was then employed to determine the weights of each indicator by ten experts. Results indicated that preventing forced work practices, protecting children from having to work, and providing minimum and fair wages for workers are the three most important indicators for assessing social impact.

Conclusions

A new SLCIA method that incorporates both quantitative and semi-quantitative indicators was proposed for assessing social impact in the electronics sector in Taiwan. Nine quantitative indicators can be easily organized using available social data from government statistics as performance reference points (PRPs) to determine the social impact exerted by companies. The relative weights were determined to allow for an impact assessment and thus solve the limitation of their currently assumed equal weights. The proposed framework is examined to analyze the social impact of three production sites for semiconductor packaging and manufacturing in Taiwan.

     

From behind the curtain: talking about values in LCA

Purpose

Practitioners of life cycle assessment (LCA) acknowledge that more input from social scientists can help advance the cause of life cycle management (LCM). This commentary offers a social science perspective on a long-running question within LCA, namely, how the field should manage not only stakeholders’ values but also those of practitioners themselves.

Methods

More than 60 interviews were conducted with LCA practitioners and their industry clients. Qualitative data were also collected through participant observation at several LCA and LCM conferences, a study of the field’s history, and extensive content and discourse analysis of LCA publications and online forums.

Results and discussion

Results show that LCA practitioners’ values are informed partly by the knowledge acquired through their LCA work. At the same time, LCA standards and professional norms implicitly advise practitioners to keep those values out of their work as much as possible, so as not to compromise its apparent objectivity. By contrast, many social scientists contend openly that value-based judgments, based on “situated knowledge,” can actually enhance the rigor, accountability, and credibility of scientific assessments.

Conclusions

LCA practitioners’ own situated knowledge justifies not only the value choices required by LCA but also their evaluative judgments of contemporary life cycle-based sustainability initiatives. This more critical voice could advance the goals of LCM while also boosting the credibility of LCA more generally.

     

Geopolitical-related supply risk assessment as a complement to environmental impact assessment: the case of electric vehicles

Purpose

Introducing a geopolitical-related supply risk (GeoPolRisk) into the life cycle sustainability assessment (LCSA) framework adds a criticality aspect to the current life cycle assessment (LCA) framework to more meaningfully address direct impacts on Natural Resource AoP. The weakness of resource indicators in LCA has been the topic of discussion within the life cycle community for some time. This paper presents a case study on how to proceed towards the integration of resource criticality assessment into LCA under the LCSA. The paper aims at highlighting the significance of introducing the GeoPolRisk indicator to complement and extend the established environmental LCA impact categories.

Methods

A newly developed GeoPolRisk indicator proposed by Gemechu et al., J Ind Ecol (2015) was applied to metals used in the life cycle of an electric vehicle, and the results are compared with an attributional LCA of the same resources. The inventory data is based on the publication by Hawkins et al., J Ind Ecol 17:53–64 (2013), which provides a current, transparent, and detailed life cycle inventory data of a European representative first-generation battery small electric vehicle.

Results and discussion

From the 14 investigated metals, copper, aluminum, and steel are the most dominant elements that pose high environmental impacts. On the other hand, magnesium and neodymium show relatively higher supply risk when geopolitical elements are considered. While, the environmental indicator results all tend to point the same hotspots which arise from the substantial use of resources in the electric vehicle’s life cycle, the GeoPolRisk highlights that there are important elements present in very small amounts but crucial to the overall LCSA. It provides a complementary sustainability dimension that can be added to conventional LCA as an important extension within LCSA.

Conclusions

Resource challenges in a short-term time perspective can be better addressed by including social and geopolitical factors in addition to the conventional indicators which are based on their geological availability. This is more significant for modern technologies such as electronic devices in which critical resources contribute to important components. The case study advances the use of the GeoPolRisk assessment method but does still face certain limitations that need further elaboration; however, directions for future research are promising.

     

Framework for integrating animal welfare into life cycle sustainability assessment

Purpose

This study seeks to provide a framework for integrating animal welfare as a fourth pillar into a life cycle sustainability assessment and presents three alternative animal welfare indicators.

Methods

Animal welfare is assessed during farm life and during slaughter. The indicators differ in how they value premature death. All three consider (1) the life quality of an animal such as space allowance, (2) the slaughter age either as life duration or life fraction, and (3) the number of animals affected for providing a product unit, e.g. 1 Mcal. One of the indicators additionally takes into account a moral value denoting their intelligence and self-awareness. The framework allows for comparisons across studies and products and for applications at large spatial scales. To illustrate the framework, eight products were analysed and compared: beef, pork, poultry, milk, eggs, salmon, shrimps, and, as a novel protein source, insects.

Results and discussion

Insects are granted to live longer fractions of their normal life spans, and their life quality is less compromised due to a lower assumed sentience. Still, they perform worst according to all three indicators, as their small body sizes only yield low product quantities. Therefore, we discourage from eating insects. In contrast, milk is the product that reduces animal welfare the least according to two of the three indicators and it performs relatively better than other animal products in most categories. The difference in animal welfare is mostly larger for different animal products than for different production systems of the same product. This implies that, besides less consumption of animal-based products, a shift to other animal products can significantly improve animal welfare.

Conclusions

While the animal welfare assessment is simplified, it allows for a direct integration into life cycle sustainability assessment. There is a trade-off between applicability and indicator complexity, but even a simple estimate of animal welfare is much better than ignoring the issue, as is the common practice in life cycle sustainability assessments. Future research should be directed towards elaborating the life quality criterion and extending the product coverage.

     

Promoting sustainability in Mexico’s building sector via environmental product declarations

Purpose

The growing phase of emerging economy countries requires the implementation of environmental assessment tools in the building sector. The use of environmental product declarations (EPDs) has risen in developed countries as one of the main tools for environmental assessment. However, at what point should developing countries follow the EPD implementation strategies used by developed countries? What are the strengths and weaknesses of EPD in the emerging economy context, and what threats and opportunities does it face within the building sector? This work aims to answer these questions by taking Mexico as a case study.

Methods

A bibliographical review was conducted to determine the key elements for EPD development in the building sector in other countries, especially those in Europe, where EPDs originated. The review also examined the experience and perspective of other countries that are starting to contemplate this type of ecolabel as an option for environmental assessment within their own building sectors, as well as industry perspectives on EPDs, especially those of small and medium-sized enterprises (SMEs). Then, Mexico’s situation in regard to these key elements was examined, with a special focus on the main stakeholders detected: government and industry. Finally, after a contrast analysis was conducted between the developed countries and Mexico, the strengths and weaknesses of EPDs in the emerging economy context and the threats and opportunities within the building sector were determined.

Results and discussion

The use of EPDs in Europe has largely followed a normative and legislative pattern. Moreover, it has been the main data source for building environmental assessment schemes, and there is a strong life cycle assessment (LCA) platform that contributes to EPD development. Furthermore, there is a European tendency toward making the use of EPDs mandatory. However, there is a very different reality in emergent economy countries. In these countries, social housing represents a major part of the vision of the building sector, so it is taken as an initial approach to EPD development. In Mexico, there is a solid legislative framework in which EPDs could be implemented, and there is a variety of environmental assessment housing programs into which EPDs could be integrated. Nevertheless, there is an institutional void that has prevented the incorporation of the life cycle approach into the national strategy of sustainability in the building sector. Moreover, SMEs might not have the technical and financial capacity to develop EPD.

Conclusions

This analysis has proved that EPD implementation in emerging countries mainly depends on two aspects: Firstly, it must be a shared vision of sustainability between government and industry, in which there is a correspondence between the sustainability objectives of the two parties and SMEs have the ability to contribute toward their achievement. Secondly, a solid platform of knowledge that supports LCA in the building sector is necessary, and it must involve a strong relationship between government, academia, and stakeholders.

     

Promoting life cycle thinking for sustainability in the mining sector of the Philippines

Purpose

This paper aims to promote life cycle thinking for the mining sector in the Philippines in enhancing the interventions intended for mining as a catalyst of sustainable development in the country. The environmental ills of mining hinder the sector’s acceptability as a catalyst, which is detrimental to its sustainability at the same time.

Methods

Previous works on mining impacts and life cycle thinking and assessment in the country had been reviewed to glean insights on integrating life cycle thinking in mining. Why and how such thinking and approach should be accounted for in mining is examined from these works to figure out the strategies through which mining is helped in mitigating its environmental ills.

Results and discussion

Life cycle thinking helps establish a logical approach in analysing issues associated with mining processes and products. It is of great relevance in preparing for contingencies for the adverse environmental outcomes that arise at any point of mining’s life cycle (exploration to mine closure) and the mining products’ life cycles (extraction to recycling or to accumulation). With its associated assessment procedures, life cycle thinking provides a logical system in obtaining scientific evidence for forward planning particularly on the aspect of sustainable mitigation of mining’s environmental outcomes.

Conclusions

It is apt that life cycle thinking be seriously accounted for in mining to improve the current undertakings of troubleshooting and addressing the adverse environmental outcomes of mining. Important insights from it facilitate the identification of sustainable mitigation strategies and who could take the lead actions, such as in developing business linkages and new markets to capitalize on the wastes and emissions from mining operations. The insights can greatly help the mining sector build its capability to come in harmony with people and nature, and work as a catalyst of sustainable development in the country.

     

International Molybdenum Association (IMOA) life cycle assessment program and perspectives on the LCA harmonization effort

Purpose

In 2001, the International Molybdenum Association (IMOA) initiated their life cycle assessment (LCA) program performing cradle-to-gate life cycle inventories (LCIs) of three molybdenum metallurgical products, followed by LCIs of eight molybdenum chemicals and an update to the metallurgical LCIs. From 2012 to 2014, IMOA participated in a multi-metal industry initiative to harmonize the methodological approach to metal-related LCAs. This paper describes some of IMOA’s conclusions formed from its program and, coupled with its involvement in the multi-metal initiative, provides some lessons learned.

Methods

For this paper, IMOA evaluated the benefits of its LCI program, including its ability to communicate effectively with member companies and stakeholders on the development, use, and application of life cycle data. Likewise, IMOA developed the competence to recognize and provide input on potentially inappropriate use of LCA. IMOA performed a literature review to highlight some of the scientific research using the molybdenum LCI data. IMOA also reviewed the metal industry’s guidance document to provide its perspective on it, including similarities, differences, and substantiation of elements of the four topic areas.

Results and discussion

The metal industry’s guidance document identified four topic areas as essential for alignment with respect to metal-related LCAs: (1) system boundaries, (2) coproduct modelling, (3) life cycle impact assessment (LCIA), and (4) metals recycling modelling. IMOA is largely in agreement with the approaches described in the document. The paper provides examples of how these have been applied to LCAs on Mo-bearing products as well as examples of how some LCA work can benefit from the guidance document.

Conclusions

Having taken part in the harmonization effort, IMOA is poised to educate its member companies and stakeholders about some of the challenging issues encountered in LCA and will continue to lead through active industry participation. IMOA supplies its LCI data via a formal request process which enables open dialogue with stakeholders and LCA practitioners while providing IMOA with insights into how its products fit into the broader lifecycle context and facilitating stakeholders’ awareness of LCA and metals.

     

Sustainability governance service providers: the role of third-party product certification in facilitating corporate life cycle management

Purpose

This article aims to analyze the role that third-party product sustainability certifications play in supply chain sustainability governance and hence the impact that they may have on facilitating corporate life cycle management (LCM). Particular emphasis is given to exploring the extent to which such schemes allow firms to outsource the work of communication, motivation, enablement, and control of sustainability-related information and performance upstream in the supply chain.

Methods

The research design is based on a comparative case study methodology. The corporate practices of sourcing the sustainability certified products in the food retailing and textile sectors are compared, to explain when third-party product sustainability certification reduces the corporate need to engage in collaborative relationships with suppliers, thereby reducing efforts associated with implementation of corporate life cycle management.

Results and discussion

In our study, we found evidence that affirms the role of third-party product sustainability certification in reducing corporate necessity to actively engage with coordination of sustainability issues upstream in the supply chain. However, we also identified a range of factors—the intention of the buying company, the supply chain context, and the design of the certification scheme—that influence the extent, to which third-party product sustainability certification replaces the corporate need for additional work to facilitate supplier compliance. Some of these factors, e.g., the design of the certification scheme, are new and have been underexplored in the supply chain management and value chain governance literature yet.

Conclusions

Our findings suggest that corporate LCM practitioners should consider third-party sustainability certification as an instrument for the transfer of significant life cycle information along the supply chain and as a tool to facilitate corporate life cycle management. The extent to which third-party product sustainability certification would be able to facilitate corporate life cycle management depends not only on whether certification requirements are based on the LCA studies but also on the market scope of the certification schemes, the scope of the certification requirements, and the architecture of the certification management services. If these parameters are aligned with corporate ambitions and allow buyers to fully outsource the work associated with communication, motivation, enablement, and control of sustainability-related information and supplier performance, the life cycle management can be exercised by companies by simply choosing to procure sustainability certified products.

     

Support for Sustainable Development Policy Decisions A Case Study from Highway Maintenance

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http://dx.doi.org/10.1065/lca2006.04.009

Goal, Scope and Method

logy. This paper describes a case study carried out as part of a wider programme to provide support for environmental decision-making in the highway maintenance programme of a local government body: Surrey County Council (SCC). UK local authorities are required to demonstrate that sustainable development principles are addressed in service provision, by improving environmental, economic or social wellbeing and improving public consultation. A methodological approach was developed to meet these requirements by using life cycle assessment (LCA) and multi-criteria decision analysis (MCDA) through the process of decision conferencing.

Results

In projects requiring strategic decisions, difficulties arise in identifying relevant sustainable development criteria and in evaluating maintenance options against these criteria where the context for decision-making is complex and characterised by uncertainty, where multiple public policy objectives compete and a number of decision-makers and key players are affected by the outcome. Clearly, a structured process is needed to engage such stakeholders in the decision process, utilising quantitative and qualitative information. The approach described proved to be capable of fulfilling these requirements.

Conclusions

and Recommendations. The approach of combining LCA with MCDA through decision conferencing is capable of further development to support other strategic decision-making activities. However, this illustrative case study has revealed a need for methodological developments in LCA for local, project-level decisions.

     

Enhancing comprehensive measurement of social impacts in S-LCA by including environmental and economic aspects

Purpose

Measurability becomes a key question in the assessment of the sustainability of products and services. As the LCA has proven its capability of measuring environmental sustainability over the last decades, the Social Life Cycle Assessment (S-LCA) seems promising as a way to cover the social dimension of sustainability within a similar framework. For operability reasons, working hours are commonly used as a single metric in product orientated S-LCA studies, even though major stakeholder groups are excluded by doing so. This paper shows how this shortcoming can be overcome through the introduction of the measurement of additional activity variables and explores different ways of implementing these variables.

Methods

This work suggests introducing the activity variables Biophysical Pressure and Added Value in addition to the commonly used working hours of involved labour forces. Biophysical Pressure reflects the negative influence of the degraded natural environment on the affected humans in addition to the direct health effect covered by standard LCA. Added Value represents the potential benefits for stakeholders due to financial investments in production. The new activity variables are derived from the MRIO database “Exiobase” and coupled with social risk indicators from the “Social Hotspot Database”. Finally, the qualitative risk classes are transformed to quantitative units and normalized to allow for a better interpretation and an optional aggregation of the three variables into a Final Social Impact score.

Results and discussion

In order to test the method’s applicability, the social impacts of products and services from two different product systems were calculated and compared. Three t-shirts and four residential housing heating systems were assessed by the developed method and compared on the basis of their respective functional units. Major differences between the social impact measured only by working hours and social impact measured by the aggregation of the three quantitative units were observed, especially since the Added Value (social benefits) dimension and working hours contrasted regionally. While the concept is functional, there are limitations related to the MRIO inventory data and to the interpretation of results; therefore, sensitivity analyses were applied.

Conclusions

The developed S-LCA method shows a promising way to extend the range of stakeholders affected by the life cycle of a distinct product by adding new variables. While constraints of MRIO data concerning detailed product system representation currently limit the approach, it allows one to identify potential social hotspots in complex product systems.

     

Geometric service life modelling and discounting,a practical method for parametrised life cycle assessment

Purpose

To evaluate the long-term advantage of reusing building elements, including reduced material consumption and waste production, life cycle assessments are purposeful. To translate these assessments in relevant design advices, it is necessary to model accurately the service life of the considered elements and acknowledge the related uncertainties. Practical methods to do this are nevertheless lacking. In reaction, this paper proposes a new assessment method: geometric service life modelling and discounting.

Methods

The developed method is extensively parametric. Its formulas express an element’s service life in terms of a limited number of variables. This facilitates the evaluation of large series of elements as well as the automation of uncertainty analyses. Further, the method tackles different modelling complexities such as the interaction between replacements and refurbishments. Taking into account these complexities aligns the assessments with realistic service lives. For the presentation of the developed method, a focus on life cycle costing is chosen.

Results and discussion

In this paper, the outcomes of the newly developed method are compared to those of an existing calculation method and benchmarked with the manual modelling and assessment of 390 simplified building elements. This comparison is based on three indicators characterising the methods’ accuracy: the number of interventions, their individual impact and their resulting net present value. For each indicator, geometric discounting led to a considerable increase of accuracy compared to the existing method.

Conclusions

From this comparison, it is concluded that geometric service life modelling and discounting offers not only a well-defined procedure for parametrised life cycle assessment studies, this method is also more accurate than the existing one. Moreover, the uncertainty analyses it facilitates illustrate how detailed assessment outcomes and relevant design advices about the effectiveness of element reuse can be obtained. Nevertheless, further research about the method’s practical implementation is required.

     

On the boundary between economy and environment in life cycle assessment

Purpose

We investigate how the boundary between product systems and their environment has been delineated in life cycle assessment and question the usefulness and ontological relevance of a strict division between the two.

Methods

We consider flows, activities and impacts as general terms applicable to both product systems and their environment and propose that the ontologically relevant boundary is between the flows that are modelled as inputs to other activities (economic or environmental)—and the flows that—in a specific study—are regarded as final impacts, in the sense that no further feedback into the product system is considered before these impacts are applied in decision-making. Using this conceptual model, we contrast the traditional mathematical calculation of the life cycle impacts with a new, simpler computational structure where the life cycle impacts are calculated directly as part of the Leontief inverse, treating product flows and environmental flows in parallel, without the need to consider any boundary between economic and environmental activities.

Results and discussion

Our theoretical outline and the numerical example demonstrate that the distinctions and boundaries between product systems and their environment are unnecessary and in some cases obstructive from the perspective of impact assessment, and can therefore be ignored or chosen freely to reflect meaningful distinctions of specific life cycle assessment (LCA) studies. We show that our proposed computational structure is backwards compatible with the current practice of LCA modelling, while allowing inclusion of feedback loops both from the environment to the economy and internally between different impact categories in the impact assessment.

Conclusions

Our proposed computational structure for LCA facilitates consistent, explicit and transparent modelling of the feedback loops between environment and the economy and between different environmental mechanisms. The explicit and transparent modelling, combining economic and environmental information in a common computational structure, facilitates data exchange and re-use between different academic fields.

     

Social life cycle assessment of average Irish dairy farm

Purpose

The majority of sustainability studies of dairy farms focused on environmental performance and profitability; however, social aspect has been hardly assessed. This study aims to investigate the social impacts of dairy farm via a case study using a social life cycle assessment framework.

Methods

The assessment was carried out applying the social LCA Guideline by UNEP-SETAC. Nineteen suitable social indicators were selected from four stakeholder categories of the guideline. Characterization and normalization were further developed based on data availability. National farm survey data was used as foreground data for farm activities, supplemented with background data from public database and life cycle working environment (LCWE) data by Gabi database. All indicators were divided into three groups: functional unit-related quantitative indicators, non-functional unit-related quantitative indicators and semi-quantitative indicators.

Results and discussion

Irish dairy farming has positive social impacts on value chain actors and society, predominantly positive impacts for local community and generally positive values for workers. The main negative impacts are health and safety issue, equal opportunity for workers, and safe and healthy living conditions for the local community. Possible actions to improve the social performance include introducing more efficient and robotic milk production systems; applying better handling methods and using real time decision support to operational management for emissions reduction.

Conclusions

This study is the first attempt of social LCA in Ireland. It demonstrated a possible method to carry out SLCA for Irish dairy sector. The results identified the positive and negative social hotspot of dairy farm with recommendation for future improvement.

     

An Italian tomato “Cuore di Bue” case study: challenges and benefits using subcategory assessment method for social life cycle assessment

Purpose

The main purpose of this study is to present an implementation of the subcategory assessment method (SAM) to the life cycle of an Italian variety of tomato called “Cuore di Bue” produced by an Italian cooperative. The case study was used to use the methodology proposed in compliance with the guidelines of social life cycle assessment (S-LCA) in order to highlight issues for the improvement of SAM. A summary of strengths and weaknesses of the methodology as well as the social performance of the considered Italian tomato is an important result of this case study.

Methods

The methodology used is based on SAM. The UNEP/SETAC guidelines of S-LCA and the complementary methodological sheets were used as main references to carry out SAM, and it was used to assess the social performances of Cuore di Bue. The focus was on the assessment of the following three out of five stakeholder groups presented in the guidelines: workers, local community and consumers. Specific questionnaires have been developed to collect the inventory data related to each stakeholder group and along the product life cycle.

Results and discussion

SAM of Cuore di Bue showed a range of values, between 2 and 3 (C-B) for consumer stakeholder group and mainly 3 (B) for the local community and worker stakeholders. Because the best performance (A) is related to a numerical value of 4, better performances were not identified, owing to no propagation of actions in the value chain. The collective bargaining, transparency, feedback mechanism and privacy are the subcategories with the worst performance, but at the same time with more potential for improvements.

Conclusions

The implementation of SAM on Cuore di Bue allowed us to demonstrate how SAM transforms qualitative data into semi-quantitative information through a score scale that can help a decision maker achieve a product overview. SAM has been implemented on Cuore di Bue; the product assessment, the strengths and weaknesses of the methodology are identified and discussed as well. It has been possible to present the best and worst performances in product life cycle, by identifying the phase or the subcategories with good or bad performance. However, in this case study, as the same company owns most of the product life cycle taken into account, the majority of social performances are identical, and this may represent a limit of the methodology or that more organisations along the life cycle must be taken into account (for example, energy, distribution).

     

Subcategory assessment method for social life cycle assessment: a case study of high-density polyethylene production in Alberta,Canada

Purpose

The aim of this study is to develop and test the applicability of a new subcategory assessment method (SAM) for social life cycle assessment using a case study on high-density polyethylene (HDPE) production by Dow Chemical Canada facility in Alberta, Canada.

Methods

The methodology is characterized by six steps: (1) definition of the goal and scope of the assessment; (2) life cycle inventory data collection including context data at country level and company-specific data for foreground processes; (3) impact assessment where the subcategories’ results for foreground processes at company level are evaluated using a new SAM developed and the country social performance in the different subcategories is evaluated using some assessment intervals; (4) comparing the social performance of foreground processes to the social background context in sector or country; (5) evaluating the social performance of background processes using sector performance evaluation from Product Social Impact Life Cycle Assessment (PSILCA) database or country performance evaluation conducted in the study; (6) and discussion and conclusion.

Results and discussion

The method developed was able to identify the subcategories that need high level or some level of improvements along the cradle-to-gate life cycle of HDPE. In addition, the stakeholders with high negative effect were highlighted in every life cycle stage. Through this approach, Dow Chemical Canada is able to prioritize its actions and focus on the areas where its performance is still low compared to its peers in the sector or compared to the situation in the country. Moreover, through using PSILCA database or country performance evaluation to investigate the social performance of background processes, Dow Chemical Canada can determine the social hotspots areas that need more focus from its suppliers.

Conclusions

Applying the new subcategory assessment approach proposed in this study provides an objective way to assess the subcategories while differentiating between two levels of assessment: (1) the commitment to the social subcategory in the company’s policy (defined as cutoff requirement) and (2) the evidence of good/bad practices of the subcategory. In addition, the comparison of performance of the companies in foreground processes to the social background in sector or country has improved the objectivity further.