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1.

Purpose

The current focus of environmental legislation for energy-using products is an efficient energy consumption in the use stage. However, the production and waste treatment of electronic products are also related to environmental impacts in terms of declining metal resources and growing waste streams. This paper investigates the environmental impacts of life time extension versus energy efficiency for the product group video projector using life cycle assessment (LCA).

Methods

The product under study was an average video projector based on three LCD projectors. The studied systems included two possibilities after a regular first usage period: reconditioning for a second use or replacement by a primary successor with an energy efficiency increase of 5 and 10%. All impacts addressed were accounted using the ReCiPe 2008 method. The impact contribution of projector components was identified at midpoint and endpoint levels, while life cycle impacts were calculated with a focus on three impact categories. Furthermore, the amortization period of production emissions was quantified.

Results and discussion

LCA results showed that the use stage dominates life cycle impacts of the global warming potential and primary energy demand. For the metal depletion potential, the production stage accounts for most of the total life cycle load. The highest shares in production emissions were identified for electronic components, namely printed wired boards and integrated circuits. Reconditioning and reuse of a secondary projector resulted in minor environmental impacts compared to the replacement and use of a primary projector with an energy efficiency increase of 5%. The saving potential of the primary energy demand is higher only in the case of a 10% more efficient device as compared to the secondary projector.

Conclusions

The study concluded that production emissions and their amortization period are relevant factors offsetting any environmentally beneficial measures applied during the use phase. The study suggests that life time extension of video projectors can provide higher environmental improvement potentials, while energy efficiency increase during usage is less beneficial, given that major improvements in energy efficiency do not occur. Recommendations are valid for this particular case study. The study suggests that the current focus of mandatory product requirements for energy-using products on energy efficiency increase should be extended to measures of life time extension in order to serve the intent of an integrated product policy.
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2.

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.
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3.

Purpose

Life cycle assessments (LCAs) are considered common quantitative environmental techniques to analyze the environmental impact of products and/or services throughout their entire life cycle. A few LCA studies have been conducted in West Africa. This study aimed to discuss the availability of LCA (and similar) studies in Nigeria, Ghana, and Ivory Coast.

Methods

An online literature review of reports published between 2000 and 2016 was conducted using the following keywords: “life cycle assessment,” “carbon footprinting,” “water footprinting,” “environmental impact,” “Nigeria,” “Ghana” and “Ivory Coast.”

Results and discussion

A total of 31 LCA and environmental studies in Nigeria, Ghana, and Ivory Coast were found; all but one were conducted after 2008. These were mainly academic and most were publicly available. The industries studied included energy sector, waste management, real estate, food sector, and others such as timber and gold. The minimal number of studies on LCAs and environmental impacts in these West African states could be because companies are failing to promote quantitative environmental studies or studies are kept internally for the use of other assessment techniques. Furthermore, it could be that academic research institutions lack cutting-edge research resources for LCA, environmental impact, carbon, and water footprinting studies.

Conclusions

Further quantitative environmental studies should be conducted in Nigeria, Ghana, and Ivory Coast to increase the understanding of environmental impacts. In these countries, the existence of LCA studies (and by association the localized life cycle inventory (LCI) datasets) is crucial as more companies request this information to feed into background processes.
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4.

Purpose

The built environment consists of a huge amount of infrastructure, such as roads and utilities. The objective of this paper is to assess the life cycle financial and environmental impact of road infrastructure in residential neighbourhoods and to analyse the relative contribution of road infrastructure in the total impact of neighbourhoods.

Methods

Various road sections are analysed based on an integrated life cycle approach, combining life cycle costing and life cycle assessment. To deal with complexity, a hierarchic assessment structure, using the principles of the “element method for cost control”, is implemented. Four neighbourhood models with diverse built densities are compared to gain insight in the relative impact of road infrastructure in neighbourhoods.

Results and discussion

The results reveal important financial and environmental impact differences between the road sections analysed. Main contributors to the life cycle financial and environmental impact are the surface layer and electrical and piped services. The contribution of road infrastructure to the total neighbourhood impact, ranging from 2 to 9 % of the total cost, is relatively limited, compared to buildings, but not negligible in low built density neighbourhoods.

Conclusions

Good spatial planning of the neighbourhood is recommended to reduce the amount of road infrastructure and the related financial and environmental impact. The priority should be to design denser neighbourhood layouts, before decreasing the financial and environmental impact of the road sections.
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5.

Purpose

Eco-labelling has become part of the business strategy of companies thanks to numerous advantages in terms of engaging with consumers and gaining market quota. The aim of this article is to present a critical discussion on the development and implementation of a new eco-label named pescaenverde, registered in Spain, as the first type III eco-label in the Spanish fishing sector that is based on life cycle approaches for seafood products.

Methods

More specifically, it aims to complement ecosystem-based eco-labels with the computation of the carbon footprint and the energy return on investment (EROI) of seafood products. Furthermore, it proposes to discuss the ecological criteria, certification process or the opportunities and challenges of the market implementation of this eco-label in detail. Finally, the authors argue that life cycle eco-labels should be considered important complements for more specific sector- or ecosystem-oriented labels already in use, rather than direct competitors.

Results and discussion

There has been much criticism towards the eco-labelling sector as regards the transparency and scientific rigour of its standards. The fishing and seafood sector, which has experienced a boom in eco-labelling in recent years, due mainly to the strength of the Marine Stewardship Council certification scheme, is not alien to this controversy, since critics advocate expanding the concept of sustainable fisheries beyond an ecosystem approach in order to account for global environmental concerns such as greenhouse gas (GHG) emissions or energy use. Not surprisingly, the European Union and other authorities currently encourage eco-labels to base their ecological criteria on life cycle approaches. Therefore, the current study discusses the ecological criteria, certification process or the opportunities and challenges of the market implementation of this eco-label in detail.

Conclusions

The specificity of the life cycle inventory scheme used in pescaenverde delivers an accurate computation of environmental impacts for the specific case of Spanish fisheries. However, the geographical expansion of this scheme to other nations or regions will be conditioned by an important software adaptation to the particular inventory characteristics of the new fisheries, fleets and products.

Recommendations

Adapting ecological criteria to other situations would also need substantial discussion, since the use of this certification scheme is not intended to contrast or compare seafood products against each other but to provide consumers with an easily identifiable label through which they can detect environmentally sustainable practices in terms of GHG emissions and energy use in the fishing fleets supporting the seafood products purchased.
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6.

Purpose

The purpose of the European SENSE project was to define an integral system to assess and communicate the environmental impacts of food products and to develop a web-based tool for Small and Medium size Enterprises (SMEs). The tool has been tested in salmon, beef-and-dairy, and fruit juice production sectors.

Methods

The SENSE project has evaluated several existing methodologies for environmental impact assessment over the life cycle including also social aspects, in order to deliver a new integral system for the environmental and social assessment of agricultural and aquaculture food products.

Results and discussion

The system includes a standardization of a data gathering system, a selection of relevant key environmental performance indicators for food supply chains and a common methodology to perform simplified life cycle impact assessment. The results are based on collected information on the use of resources and emissions generated along the supply chain of food or drink products. The main result is a web-based software tool that is based on a summation of the partial impacts of the different steps in food supply chains. In this software, different actors in the supply chain can enter their own data and link them to the data of other companies. The results obtained in the tool could be used for at least six different approaches: (i) environmental impact assessment of the product, (ii) food chain hot spot identification, (iii) comparison of hypothetical or real improvement scenarios, (iv) assessment of the environmental impact development over the years, (v) benchmarking opportunity for the companies, and (vi) a business to business communication strategy. The scientific robustness of the tool has been tested comparing the obtained results with the same analysis with commercial software.

Conclusions

The SENSE tool is a simplified tool designed for food and drink SMEs to assess their sustainability on their own. This cannot be fully compared to a complete LCA study. The testing with SMEs showed that they need additional support for filling in the questionnaires correctly and interpret the results. The simplified evaluation of environmental impacts based on a life cycle approach could lead to benefits to SMEs within the food industry. The future application and development of the tool will be focused on adapting the tool to the Product Environmental Footprint initiative requirements and self-assessment opportunities.
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7.

Purpose

The static functional unit definition in the current LCA framework has limitations in addressing the changing product functionality and associated environmental impact of constantly evolving product technologies. As a result, it overlooks the changes in consumer behaviour of increased consumption of products in provided services as well as in growing volumes. This article aims to present a new framework in defining a dynamic functional unit of product technologies that caters for changes in consumer behaviour and growing market.

Methods

A new approach to defining the functional unit is proposed that caters for changes in consumer behaviour and the use of technology from a technical performance perspective. A dynamic approach to definition of the functional unit is proposed that is based on Kano’s model of product function and satisfaction.

Results and discussion

The new approach is demonstrated on a case study in which the analysis of historical data for two TV product technologies—CRT and LCD—is used to show how the total environmental impact is increasing due to the increased functionality which triggers an increase in the volume of the market. Despite the efforts of improving product life cycle design, the society is still faced with increasing environmental impact from the product type overall.

Conclusions

This article presents the challenges of using a static, single functional unit definition in an industrial culture with constant evolution of products that influences usage behaviour and demonstrates the vicious circle of improving product efficiency that leads to further consumption and environmental impact. To address this problem, a new framework of dynamic functional unit definition is put forward for performing comparative LCA to manage the development of product life cycle design that helps keep the total environmental impact of the company’s product portfolio within absolute boundaries.
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8.

Background, Goal, and Scope

Currently, only 40%, or 44.5 million metric tons, of coal combustion products (CCPs) generated in the United States each year by electric utilities are diverted from disposal in landfills or surface impoundments and recycled. Despite promising economic and environmental savings, there has been scant attention devoted to assessing life cycle impacts of CCP disposal and beneficial use. The objective of this paper is to present a life cycle inventory considering two cases of CCP management, including the stages of coal mining and preparation, coal combustion, CCP disposal, and CCP beneficial use. Six beneficial uses were considered: concrete production, structural fills, soil amendments, road construction, blasting grit and roofing granules, and wallboard.

Methods

Primary data for raw material inputs and emissions of all stages considered were obtained from surveys and site visits of coal-burning utilities in Florida conducted in 2002, and secondary data were obtained from various published sources and from databases available in SimaPro 5.1 (PRé Consultants, Amersfoort, The Netherlands).

Results

Results revealed that 50 percent of all CCPs produced, or 108 kg per 1,000 kg of coal combusted, are diverted for application in a beneficial use; however, the relative amounts sold by each utility is dependent on the process operating parameters, air emission control devices, and resulting quality of CCP. Diversion of 50% of all CCPs to beneficial use applications yields a decrease in the total raw materials requirements (with the exception of gravel and iron) and most emissions to air, water, and land, as compared to 100% disposal.

Discussion

The greatest reduction of raw materials was attributed to replacing Portland cement with fly ash, using bottom ash as an aggregate in concrete production and road construction in place of natural materials, and substituting FGD gypsum for natural gypsum in wallboard. The use of fly ash as cementitious material in concrete also promised significant reductions in emissions, particularly the carbon dioxide that would be generated from Portland cement production. Beneficial uses of fly ash and gypsum showed reductions of emissions to water (particularly total dissolved solids) and emissions of metals to land, although these reductions were small compared to simply diverting 50% of all CCPs from landfills or surface impoundments.

Conclusions

This life cycle inventory (LCI) provides the foundation for assessing the impacts of CCP disposal and beneficial use. Beneficial use of CCPs is shown here to yield reductions in raw material requirements and various emissions to all environmental compartments, with potential tangible savings to human health and the environment.

Recommendations and Perspectives

Extension of this life cycle inventory to include impact assessment and sensitivity analysis will enable a determination of whether the savings in emissions reported here actually result in significant improvements in environmental and human health impacts.
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9.

Purpose

The consequential inventory modeling approach for life cycle assessment implies that an increase in the demand for a specific product is met by the marginal suppliers within the market. The identification of marginal suppliers is however complicated by difficulties in defining appropriate geographical market delimitations. In this study, an advanced system thinking approach is proposed to address this challenge in the identification of marginal supplying countries of wood products.

Methods

Groups of countries which represent geographical markets are identified from trade data by using a network analysis-based clustering technique. Within these markets, marginal supplying countries are selected based on positive historical increments. The analysis covers 12 different products and all countries in the world using trade data for the period 1998–2013.

Results and discussion

Global indices allow differentiating how product-specific trade networks are separated into communities and how interconnected these networks are. Large differences between products and minor differences between trade years are observed. Communities identified for each product tend to overlap with existing geographical regions and seem thus realistic. By combining this information with product-specific production increment rankings, marginal supplying countries of wood products were identified.

Conclusions

The identified geographical market delimitation is a key for proper consequential life cycle assessment (LCA) inventory modeling in areas such as timber-based construction and biomass-based energy production. The method can in principle be applied to any product for which trade network data are available and ideally should be accompanied by a detailed analysis of technological constrains within the identified supplying country.
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10.

Purpose

This study presents a life cycle assessment (LCA)-based sustainable and lightweight automotive engine hood design and compares the life cycle energy consumption and potential environmental impacts of a steel (baseline) automotive engine hood with three types of lightweight design: advanced high strength steel (AHSS), aluminum, and carbon fiber.

Methods

A “cradle-to-grave” LCA including the production, use, and end-of-life stages is conducted in accordance with the ISO 14040/14044 standards. Onsite data collected by Chinese automotive companies in 2015 are used in the assessment. The Cumulative Energy Demand v1.09 method is applied to evaluate cumulative energy demand (CED), and the International Panel on Climate Change 2013 100a method is used to estimate global warming potential (GWP 100a).

Results and discussion

Among the different lightweight designs for the engine hood, the aluminum design is the most sustainable and has the lowest CED and GWP (100a) from a life cycle perspective, which is based on a lifetime driving distance of approximately 150,000 km. In addition, the AHSS design is also sustainable and lightweight. The carbon fiber design results in higher CED and GWP (100a) values than the steel (baseline) design during the life cycle but results in the largest CED and GWP (100a) savings through waste material recycling. The AHSS design exhibits the best break-even distance based on CED and GWP (100a) within 150,000 km.

Conclusions

Sensitivity analysis results show that the lifetime driving distance and material recycling rate have the largest impacts on the overall CEDs and GWPs of the three lightweight designs.
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11.

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.
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12.

Purpose

In the near future, the products of Thai industries and companies mainly producing parts and products for export to the European Union (EU) will require the Product Environmental Footprint (PEF) to assess the environmental performance and resource efficiency of products by using a life cycle perspective. The potential generic (often used interchangeably with background data) data have to be modified and improved for mandatory use in the product-specific and country-specific PEF database.

Methods

PEF is used as a tool for assessing the environmental burden of products and services for export to the EU. It requires both specific data from primary sources and generic data to fulfill assessment requirement. Accordingly, the Thai national life cycle inventory (LCI) database plays a key role in generic data that was used to evaluate the environmental performance of products. This paper presents the perspective of Thai data readiness for PEF in which the quality of LCI is the main issue of concern. The current situation of the Thai national LCI database was reviewed. Then, the gaps of data were addressed, and the gaps were also filled. Non-representative data and untreated waste are the selected issues that were presented in this paper.

Results and discussion

Many gaps were revealed for the Thai national LCI database because this database was developed based on ISO 14040/44, which may not be compliant with the PEF guide. The issues that have been selected for improvement are non-representative data and untreated waste because these gaps can offer inaccuracy concerning the environmental burden of products potentially leading to the reliability of products for export to the EU. However, the Thai national LCI database has not achieved the data quality aspects of the PEF, continuously improving the quality of data to meet the requirements of the PEF.

Conclusions

The lessons learned from the real-world situation of data quality development based on PEF requirements were extracted. The practical procedure and recommendations were transparent for drivers and researchers who would like to start with data quality issues and prepare for the EU single market.
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13.

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.
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14.

Purpose

Regionalization in life cycle assessment (LCA) has focused on spatially differentiated environmental variables for regional impact assessment models. Relatively less attention has been paid to spatial disparities in intermediate flows for life cycle inventory (LCI).

Methods

First, we compiled state-specific LCIs for four major crops in the USA and evaluated their geographic variability in the characterized results due to the differences in intermediate inputs. Second, we evaluated the consequence of choosing average or region-specific LCIs in understanding the life cycle environmental implications of land use change from cotton to corn or soybean. Finally, we analyzed the implications of our findings in characterizing the uncertainties associated with geographic variability under the conventional pedigree approach.

Results and discussion

Our results show that spatial disparities in LCI alone lead to two to fourfold differences in characterized results for most impact categories. The differences, however, increase to over an order of magnitude for freshwater ecotoxicity and human health non-cancer. Among the crops analyzed, winter wheat shows higher variability partly due to a larger difference in yield. As a result, the use of national average data derived from top corn and soybean producing states significantly underestimates the characterized impacts of corn and soybean in the states where land conversion from cotton to corn or soybean actually took place. The results also show that the conventional pedigree approach to uncertainty characterization in LCA substantially underestimates uncertainties arising from geographic variability of agriculture. Compared to the highest geometric standard deviation (GSD) value of 1.11 under the pedigree approach, the GSDs that we derived are as high as 7.1, with the median around 1.9.

Conclusions

The results highlight the importance of building regional life cycle inventory for understanding the environmental impacts of crops at the regional level. The high geographic variability of crops also indicates the need for sector-specific approaches to uncertainty characterization. Our results also suggest that the uncertainty values in the existing LCI databases might have been signficantly underestimated especially for those products with high geographic variability, demanding a cautious interpretation of the results derived from them. 
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15.

Purpose

In the light of anthropogenic resource depletion and the resulting influences on the greenhouse effect as well as globally occurring famine, food waste has garnered increased public interest in recent years. The aim of this study is to analyze the environmental impacts of food waste and to determine to what extent consumers’ behavior influences the environmental burden of food consumption in households.

Methods

A life cycle assessment (LCA) study of three food products is conducted, following the ISO 14040/44 life cycle assessment guidelines. This study addresses the impact categories climate change (GWP100), eutrophication (EP), and acidification (AP). Primary energy demand (PED) is also calculated. For adequate representation of consumer behavior, scenarios based on various consumer types are generated in the customer stage. The customer stage includes the food-related activities: shopping, storage, preparation, and disposal of food products as well as the disposal of the sales packaging.

Results and discussion

If the consumer acts careless towards the environment, the customer stage appears as the main hotspot in the LCA of food products. The environmental impact of food products can be reduced in the customer stage by an environmentally conscious consumer. Shopping has the highest effect on the evaluated impact categories and the PED. Additionally, consumers can reduce the resulting emissions by decreasing the electric energy demand, particularly concerning food storage or preparation. Moreover, results show that the avoidance of wasting unconsumed food can reduce the environmental impact significantly.

Conclusions

Results of this study show that the influence of consumer behavior on the LCA results is important. The customer stage of food products should not be overlooked in LCA studies. To enable comparison among results of other LCA studies, the LCA community needs to develop a common methodology for modeling consumer behavior.
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16.

Purpose

Many applications of life cycle assessment do not consider the variability of the service lifetime of different structures, and this may be a relevant factor in an environmental impact assessment. This paper aims to determine the influence of the service lifetime on the potential environmental impacts of wooden and concrete poles in the electricity distribution system.

Methods

The estimation of service lifetime was conducted using the factorial method. The life cycle assessment was applied using SimaPro software and considered the entire life cycle of utility poles, from the extraction of raw materials to the final disposal. Then, an evaluation of the environmental impacts using the CML IA baseline method was performed. The study included the analysis of uncertainty using the Monte Carlo method.

Results and discussion

In general, the wooden poles had a lower potential environmental impact compared to the concrete poles. The result of the sensitivity analysis considering the variability of the chromated copper arsenate wood preservative retention rate suggests that the frequency of maintenance affects the service lifetime. Often, the comparison of products in the LCA perspective is carried out by considering similar useful lifetime services for the different alternatives, and this study shows that the environmental performance of products or services is directly proportional to the lifetime. It is a crucial parameter that has to be clarified in order to reduce uncertainty in the results.

Conclusions

Thus, some factors such as material quality, design adjustments and routine maintenance extend the service lifetime of a product or process and are shown to be effective ways to reduce environmental impacts. Therefore, the service lifetime has a significant influence on the development of the life cycle assessment. Comparative LCA studies are often sensitive to parameters that may even change the ranking of selected impact categories. All in all, from the sensitivity analysis highlighted in this study, the variability of lifetime service has proven to be one of the most prominent factors influencing comparative LCA results.
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17.

Purpose

This study analyses the environmental impacts referring to dairy products and to the operation of a dairy. The study aims to better understand different process stages in a dairy operation. This analysis can be used to improve the flows of energy, water, and materials in the dairy operation. The results are also used to suggest an improved allocation model for assigning the impacts of operation to single dairy products.

Methods

The analysis is based on a detailed, product-specific model calculation for the use of energy, water, and chemicals for more than 40 subprocesses of a dairy operation. This model has been used to elaborate the life cycle inventory for a detailed life cycle assessment study. The environmental impacts are analyzed from cradle to gate including and excluding the raw milk input. The environmental impacts are assessed with the midpoint indicators suggested by the International Reference Life Cycle Data System. Finally, results of this study are compared with an allocation model recommended for life cycle assessment (LCA) studies on milk products.

Results and discussion

The analysis of the model dairy shows that raw milk production has the main impact in all categories. Consumer packaging has the second biggest impact in many categories. The detailed dairy processing model allows the assignment of inputs and outputs for each subprocess to single dairy products and thus avoids allocation largely. The analysis of inputs to different dairy products per kilogram shows that ultra-high-temperature (UHT)-processed milk uses more chemicals for cleaning compared to the other products. Cream uses more electricity and heat compared to UHT milk and to yogurt.

Conclusions

A detailed discussion shows the overlaps and differences found for the allocation of inputs to the milk processing to final dairy products. Allocation models for different types of inputs are partly confirmed by the detailed theoretical model used for this LCA. The allocation of chemicals, steam, and electricity to single products can be improved based on the detailed dairy model developed in this study.
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18.

Purpose

In an effort to reduce the environmental impacts of the furniture sector, this study aimed to diagnose the environmental performance of an office cabinet throughout its life cycle.

Methods

An attributional life cycle assessment (LCA) was used, based on the ISO 14044 Standard and ILCD Handbook. The scope of the study considered the entire supply chain, from cradle to grave, including the steps of pre-manufacturing, manufacturing, use, and post-use of the product. The impact assessment method was the International Reference Life Cycle Data System (ILCD) 2011 midpoint.

Results and discussion

The results identified that the most significant environmental impact of the furniture life cycle was due to the distances covered and production of the main raw material, wood medium-density particleboard (MDP). The evaluation of transport scenarios showed environmental tradeoffs for truck fuel switches and environmental gains for the distribution of MDP from closer suppliers by truck, as well as from current supplier by truck and ship in the major categories. Furthermore, evaluation of the office cabinet post-use options showed that reuse, recycling, or energy recovery from waste cause significant environmental gains in the major categories. Wooden furniture is a potential carbon sink if its life cycle does not emit more greenhouse gases than its materials can store. The impacts of substitution scenarios varied depending on the type of product avoided.

Conclusions

The LCA proved a powerful method to diagnose and manage environmental impacts in complex product systems. The sensitivity analysis showed that it is possible to reduce the environmental impacts and, at the same time, make the furniture industry increase its economic gains and net carbon stock in the anthroposphere.
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19.

Purpose

This paper introduces the new EcoSpold data format for life cycle inventory (LCI).

Methods

A short historical retrospect on data formats in the life cycle assessment (LCA) field is given. The guiding principles for the revision and implementation are explained. Some technical basics of the data format are described, and changes to the previous data format are explained.

Results

The EcoSpold 2 data format caters for new requirements that have arisen in the LCA field in recent years.

Conclusions

The new data format is the basis for the Ecoinvent v3 database, but since it is an open data format, it is expected to be adopted by other LCI databases. Several new concepts used in the new EcoSpold 2 data format open the way for new possibilities for the LCA practitioners and to expand the application of the datasets in other fields beyond LCA (e.g., Material Flow Analysis, Energy Balancing).
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20.

Purpose

We evaluated and quantified the environmental impact of a radial tire product for passenger vehicles throughout the product’s life cycle to identify key stages that contribute to the overall environmental burden and to find ways to reduce these burdens effectively. The study covers all relevant life cycle stages, from the acquisition of raw materials to the production, use, and end of life.

Methods

Data collected onsite in 2014 by one of the largest Chinese tire companies were used in the assessment. The evaluation is presented in terms of individual impact category according to the CML model. Five impact categories (i.e., global warming potential (GWP), acidification potential (AP), photochemical oxidant creation potential (POCP), eutrophication potential (EP), and human toxicity potential (HTP)) were considered. The research was conducted in accordance with the ISO 14040/14044 standards.

Results and discussion

Fuel (gasoline) consumption represents an important contribution to most impact categories, including the GWP, AP, POCP, and EP, during the use stage. The largest contributor to the HTP category is raw material acquisition, mainly because of the impact of the production of organic chemicals. In the end-of-life stage, assuming that 100 % of used tires are collected and recycled to produce reclaimed rubber, the GWP, EP, and HTP contributions are negative, whereas those to the AP and POCP are positive. During the raw material acquisition stage, natural rubber, synthetic rubber, carbon black, and organic chemicals represent the largest contribution to the environmental impact categories. During the production stage, the compound blending process is the largest contributor to the AP and POCP, whereas vulcanizing and testing contribute most to the GWP, EP, and HTP.

Conclusions

Vehicle fuel consumption and its proportion consumed by the tires during the use stage are key factors that contribute to environmental impact during tire life. Further investigations should be conducted to decrease the impact of these factors and improve the environmental performance of tire products.
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