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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Enforcing sustainable sourcing: A framework based on best practices

Tkachenko, Sergii, Rib, Kristina January 2014 (has links)
Problem – Companies are increasingly focusing on sustainability issues in response to internal and external pressure. Research on sustainable performance of focal companies is vast; however there is a lack of guidelines for managing sustainability in extended supply chains. Scholars claim a need for additional research on intra- and inter-organizational diffusion of best sustainable practices. Besides, the outcomes of sustainable sourcing practices are still uncertain. The gap between potential benefits of sustainable sourcing and actual performance is attributed to lack of capabilities, instruments, and efficient processes. Purpose – The purpose of this paper is to explore existing sustainable sourcing practices which are used by leading multinational companies. Based on the obtained knowledge we aim to develop a framework that will suite as a guideline for enforcing sustainable sourcing practices. Method – The research has been conducted through the method of grounded theory, enabling the researchers to constructively interpret data from documentary primary data and semi-structured interviews. This approach was utilized in order to explore what are the most common practices of managing sustainable sourcing applied by the companies awarded as Industry leaders by the Dow Jones Sustainability Index. Conclusion We found that a commonly accepted approach towards managing and enforcing sustainable sourcing is absent both in theoretical discourse and practice. However, the most frequently mentioned tools and approaches were defined. They include the adoption of suppliers’ code of conduct, establishment of dedicated sustainability departments, procurement personnel training, suppliers’ capability building, risk assessment and categorization of suppliers, IT platforms for information sharing, supplier self-assessment, audit, joint projects with suppliers, meetings and conferences, and suppliers’ scorecards. Finally, we developed a Sustainable Sourcing Enforcement framework which could serve as a guideline to enforce supplier’s commitment to act sustainably. The framework consists of five chronologically connected pillars: Objectives alignment, Commitment creation, Supplier selection, Ongoing development and Work with stakeholders.
72

AVALIAÇÃO DO CICLO DE VIDA - ACV DE UM SISTEMA DE WETLAND CONSTRUÍDO DE FLUXO VERTICAL PARA O TRATAMENTO DE ESGOTO DOMÉSTICO / LIFE CYCLE ASSESSMENT LCA OF A VERTICAL FLOW CONSTRUCTED WETLAND FOR WASTEWATER TREATMENT

Alves, Desirê Armborst 22 September 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The wastewater treatment system by constructed wetland takes into account the basic principles of natural wetlands for modification of water quality, however, it has controlled hydraulic flow and is constructed according to the desired treatment efficiency. At the Federal University of Santa Maria a vertical flow constructed wetland was designed to treat 1500 liters of wastewater per day, equivalent to that generated by 10 inhabitants of the House of College Student II, in the city of Santa Maria - RS. As every environment-modifying activity, the construction and operation of the constructed wetland result in environmental impacts, which may be positive or negative. To assess these impacts a Life Cycle Analysis - LCA was held on the wastewater treatment system. Considered one of the most complete tools for assessing environmental impacts, the LCA aims a detailed study of possible emissions from a process or product. The LCA of UFSM s constructed wetland was performed using the survey data of all building materials used in the work and the wastewater treatment parameters, and followed the steps defined by the ISO 14040 and 14044 (ABNT, 2009). For impact assessment, Ecoinvent data library and SimaPro 8® software were used. The interpretation of the results of the constructive phase was performed by ReCiPe method and the operation phase by CML method. Besides, analysis of the energy consumed in the manufacture of all construction materials was performed by Cumulative Energy Demand. The results showed that the bricks, steel and concrete were the most striking materials in all categories examined, with PVC, lime and sand the less striking materials. The bricks and cement represent 42.7% and 29.5%, respectively, of the impact of climate change category. Methane and nitrous oxide generated during the wastewater treatment are responsible for the occurrence of the environmental impact of climate change, cause by the 95% and 5% methane by nitrous oxide. COD, TKN and TP cause eutrophication representing 8.8%, 26.53% and 64.63% of impacts, respectively. Methane is related to the formation of photochemical oxidants. The energy consumed in operation during the life cycle of the system has an impact in all environmental categories analyzed by the software, with minimum impacts, taking into account the system s low power consumption. / O sistema de tratamento de esgoto por wetland construído leva em consideração os princípios básicos dos wetlands naturais para a modificação da qualidade da água, porém, contam com o fluxo hidráulico controlado e são construídos de acordo com a eficiência desejada de tratamento. Na Universidade Federal de Santa Maria foi instalado um wetland construído de fluxo vertical, projetado para tratar 1.500 litros por dia de esgoto doméstico, equivalente ao gerado por 10 habitantes da Casa do Estudante Universitário II, na cidade de Santa Maria RS. Como toda atividade modificadora do meio ambiente, a construção e a operação do wetland construído resultam em impactos ambientais, que podem ser positivos ou negativos. Para avaliação destes impactos realizou-se a Análise do Ciclo de Vida ACV do sistema de tratamento de esgoto. Considerada uma das ferramentas mais completas de avaliação de impactos ambientais, a ACV objetiva o estudo detalhado das possíveis emissões geradas por um processo ou produto. A ACV do wetland construído da UFSM foi realizada através do levantamento de dados de todos os materiais de construção utilizados na obra e dos parâmetros do tratamento do esgoto, e seguiu as etapas definidas pelas NBR ISO 14.040 e 14.044. Para avaliação dos impactos fezse uso da biblioteca de dados Ecoinvent, do software SimaPro 8®. A interpretação dos resultados da fase construtiva foi realizada por meio do método ReCiPe, e da fase de operação através do método CML. Ainda foi realizada a análise da energia consumida na fabricação de todos os materiais de construção, através do método Demanda Acumulada de Energia. Os resultados mostraram que os tijolos de cerâmica, o aço e o cimento foram os materiais mais impactantes em todas as categorias analisadas, sendo o PVC, a cal e a areia os materiais menos impactantes. Os tijolos e o cimento representam 42,7% e 29,5%, respectivamente, dos impactos na categoria mudanças climáticas. O metano e o óxido nitroso gerados durante o tratamento de esgoto são os responsáveis pela ocorrência do impacto ambiental mudanças climáticas, causado 95% pelo metano e 5% pelo óxido nitroso. A DQO, o NTK e o PT causam a categoria de impacto eutrofização, representando 8,8%, 26,53% e 64,63% dos impactos, respectivamente. O metano está relacionado à formação de oxidantes fotoquímicos. A energia consumida na operação durante a vida útil do sistema causa impactos em todas as categorias ambientais analisadas através do software, sendo mínimos estes impactos, levando em conta o baixo consumo de energia do sistema.
73

Using Blue Mussels as a Tool for Mitigating Eutrophication in the Baltic Sea

Ståhle, Johanna, Henriksson, Linnea January 2018 (has links)
Eutrophication is a consequence of excess nutrients in the water which leads to increased algaegrowth, reduced water transparency and hypoxic bottoms. This is the biggest environmental problemfor the Baltic Sea which recently has resulted in stricter legislations and other initiatives to help theBaltic Sea to recover. However, the actions to reduce the nutrient input to the Baltic Sea have so farmainly been land-based. These actions seem to not be enough since the eutrophication continues tobe a problem for the Baltic Sea. Farming blue mussels has shown to have a mitigating effect on theeutrophication and could thus be a complementary action. Blue mussels are filter-feeding specieswhich means that they filter water for food and thus eat phytoplankton and accumulate nutrients atthe same time. When the blue mussels are removed from the sea, so is the nutrients accumulated inthe mussels, resulting in a mitigation of nutrients and thereby the eutrophication. Due to the brackishwater with the low salinity in the Baltic Sea, the blue mussels farmed there do not grow bigger thanaround 3 cm. This means that the mussels are not suitable for human food production and theharvested mussels need to be used for something else, even though the farming itself is anenvironmental action. Three possible mussel products from valorisation of the Baltic Sea blue musselshave been identified; producing mussel meal, biogas or compost.Region Östergötland is involved in a project, Baltic Blue Growth, with the main objective to study howto use mussel farming as an environmental measure and which of the three valorisation options is themost beneficial from an environmental perspective. This study is a part of their investigation to reachtheir goal and will study their mussel farm in St. Anna and the three valorisation options from anenvironmental perspective. The aim of this study is thus to investigate the net nutrient reduction froma mussel farm in the Baltic Sea in combination with the contribution to climate change. This is donefrom a life cycle perspective to include the valorisation of the mussels into the different productsmussel meal, biogas or compost. For this, an existing farm in the archipelago of St. Anna, Östergötland,Sweden is studied. The main results show that there is a nutrient reduction from the mussel farm andthis is not majorly affected regardless of which valorisation option that is chosen. However, the musselfarm does have an impact on climate change and the magnitude of the impact varies for the threevalorisation options. The results of the sensitivity analysis show that the result from the life cycle canbe improved with future improvements of the mussel farm and transportation. The nutrient reductioncan become larger and the impact on the climate change can be reduced. Outside the result from thelife cycle analysis it is discussed that there are other future improvement possibilities in the productionof the mussel products, which would impact the result. The mussel farm and the mussel products alsohave other positive impacts that is not included in the life cycle analysis but discussed in the study,such as increased water transparency, recycling of nutrients and reduction of over fishing. However,the mussel farm could also have negative impacts, such as emissions of microplastics and locallyincreased sedimentation which affect the hypoxia. Those are discussed in this study but the probabilityand possible impact of them are not fully investigated and need further research.
74

Alternative Fuels for Transportation : A Sustainability Assessment of Technologies within an International Energy Agency Scenario

Ahmed, Shehzad, Conradt, Marcos H. K., Pereira, Valeria De Fusco January 2009 (has links)
Transport sector is an essential driver of economic development and growth, and at the same time, one of the biggest contributors to climate change, responsible for almost a quarter of the global carbon dioxide emissions. The sector is 95 percent dependent on fossil fuels. International Energy Agency (IEA) scenarios present different mixes of fuels to decrease both dependence on fossil fuels and emissions, leading to a more sustainable future. The main alternative fuels proposed in the Blue map scenario, presented in the Energy Technologies Perspective 2008, were hydrogen and second-generation ethanol. An assessment of these fuels was made using the tools SLCA (Sustainability Life Cycle Assessment) and SWOT Analysis. A Framework for Strategic Sustainable Development (FSSD) is the background used to guide the assessment and to help structure the results and conclusions. The results aim to alert the transport sector stakeholders about the sustainability gaps of the scenario, so decisions can be made to lead society towards a sustainable future. / <p>Phone number 0708293568</p>
75

Nouvelles approches pour l'évaluation environnementale des biocarburants avancés / New approaches for the environmental evaluation of advanced biofuels

Menten, Fabio Machado 26 March 2013 (has links)
L'Analyse de Cycle de Vie (ACV) a été explicitement employée, dans le cadre législatif en Europe et aux Etats-Unis afin de quantifier les bénéfices de filières biocarburants vis-à-vis des objectifs de réduction d'émissions des gaz à effet de serre (GES) et d'indépendance énergétique. Nous investiguons, au cours de cette thèse, la concordance du développement des biocarburants avancés (éthanol lignocellulosique, Biomass to Liquids - BTL, EMHV/HVO à partir de microalgues) avec ces objectifs par le biais de deux travaux indépendants. Le premier est une méta-analyse (synthèse de littérature) des études ACV appliquées aux filières de biocarburants avancés. Dans cette partie de la thèse, en utilisant des méthodes économétriques, nous identifions et quantifions les facteurs qui impactent le plus les résultats d'émissions de GES au long du cycle de vie des produits étudiés et calculons l'intervalle de confiance pour ces résultats. Le deuxième travail est une ACV conséquentielle et prospective illustrée par une étude de cas concernant l'introduction du BTL en France. Nous avons adapté un modèle prospectif de type TIMES pour la réalisation d'évaluations environnementales. De cette façon, nous prenons en compte des mécanismes économiques à l'origine d'impacts sur d'autres systèmes de la production de biocarburants. Ainsi, nous contribuons aux développements méthodologiques autour de l'ACV conséquentielle et prospective avec des discussions sur la définition de l'unité fonctionnelle, la définition des frontières du système, l'inclusion d'aspects dynamiques dans la caractérisation d'impacts, l'utilisation de scénarios (différents contextes politiques et économiques) et la réalisation des analyses de sensibilité sur les frontières du système pour mettre en évidence les limites du modèle utilisé. / Life Cycle Assessment (LCA) has been used in legislative texts in Europe and in the United States to quantify the benefits of biofuel production in terms of greenhouse gas (GHG) emissions reductions and energy security. In this thesis, we propose two independent approaches to investigate the compliance of advanced biofuels (cellulosic ethanol, Biomass to liquids - BTL, microalgae FAME/HVO) production with these objectives. The first one is a meta- analysis (literature synthesis) of LCA studies concerning advanced biofuels. Using econometric methods, we are able to identify and quantify the main factors impacting GHG emission LCA results. Also, we estimate a confidence interval for these results for each type of advanced biofuel in question. The second part of this work is a consequential and prospective LCA illustrated by a case study about the introduction of BTL technology in France. A long-term TIMES-type energy model was adapted for environmental evaluations in order to capture impacts occurring in affected systems through economic mechanisms. We contribute, with this work, for a proper systematization of consequential and prospective LCA. We discuss the functional unit and system boundaries definitions, the use of dynamic impact characterization factors, the use of scenarios (different political and economical contexts) and the exploration of the system's boundaries to bring attention to the limits of the model employed.
76

Material choices for the building frame : Effects on the accomplishment of the Sustainable Development Goals’ targets

Nyberg, Fanny January 2020 (has links)
Potential synergy effects and conflicts, so-called interactions, between a climate action that aims to mitigate the climate impact and five targets of the Sustainable Development Goals are identified in this study. The climate action is Conscious material choices for the frame, and the materials assessed are climate improved concrete and domestic wood. Standard concrete is used as the business as usual scenario. A pre-school building is used as an example building to demonstrate the difference in the climate impact of a frame made from the two materials assessed in the study. Life cycle assessments (LCA) of the frames shows that the domestic wood frame has a lower climate impact than the climate improved concrete frame.Two methods are used in this study. The first method is making an LCA for transportation of the materials assessed to see the environmental impact, and there is one scenario for each material where the transportation method is by a truck and one that is by train. The second method used for the study is a goal interaction scoring-method from “A draft framework for understanding SDG interactions” by Nilsson et al. (2016) that gives the interactions a score based on specific criteria. The scores are visualised in a colour coordinated matrix. The interactions generate synergies if the sums of the scores in the matrix are positive and will likely help accomplish the target. If the sums of the scores in the matrix are negative, it indicates that there are conflicts that could endanger the possibilities to reach the target.LCA of the transport scenarios shows that when the transportation distance is long, the climate impact is lowest when transporting as much as possible of the materials by train. Transporting the domestic wood for the frame by train (for longer distances) has a lower climate impact than transporting the climate improved concrete. For shorter distances, there is not a significant difference between transportation by truck or by train. The climate improved concrete gets score 0, meaning that there are neither positive nor negative interactions for the chosen material for the frame. The domestic wood gets the score +8, which indicates that there are synergies. Both the climate improved concrete and the domestic wood should not interfere with the accomplishment of the Sustainable Development Goal’s targets. However, the domestic wood for the frame generates more synergies and by choosing the domestic wooden frame for a building using a train as a transportation of the material when possible has the lowest environmental impact of the assessed materials for the frame. / <p>2020-06-08</p>
77

Analyse de cycle de vie conséquentielle appliquée aux ensembles bâtis / Consequential life cycle assessment applied to buildings

Roux, Charlotte 26 September 2016 (has links)
La construction et la réhabilitation des bâtiments et des quartiers induisent des dommages environnementaux de nature diverse (consommation de ressources, émissions de substances toxiques, atteintes aux écosystèmes). De plus, ces impacts peuvent être générés de manière indirecte (déchets radioactifs produits par la consommation d’électricité par exemple). D’où l’importance d’une approche d’évaluation environnementale holistique et multicritère. L’analyse de cycle de vie (ACV) correspond à ce cahier des charges. Cette méthode a été appliquée pour évaluer la contribution d’un bâtiment ou d’un quartier à un ensemble de thématiques environnementales (au contraire d’un outil monocritère comme le bilan carbone) et ce sur l’intégralité du cycle de vie : fabrication des matériaux, construction, utilisation, rénovation, démolition et traitement des déchets. Cette méthode peut être utilisée à différente étapes d’un projet : définition d’objectifs de programme, aide à la conception, aide à la gestion, aide à la rénovation, aide à la stratégie de déconstruction.Cette thèse s’inscrit dans le cadre de l’application de l’ACV à l’éco-conception des ensembles bâtis, de la maison individuelle jusqu’au quartier multifonctionnel. L’objectif est d’améliorer la qualité de l’aide à la décision fournie par les outils d’éco-conception en matière de réalisme et de précision des études.Trois axes de travail en interaction ont été explorés :- Conséquentiel : Quels apports conceptuels et pratiques peut-on mettre en œuvre sur la base des recherches sur l’ACV conséquentielle ?- Dynamique : Comment intégrer les interactions dynamiques entre le parc bâti et son système d’arrière plan, en particulier le système électrique?- Prospectif : Comment tenir compte de la longue durée de vie des ensembles bâtis ?La thèse propose premièrement un nouveau cadre conceptuel pour l’évaluation des projets de conception et de réhabilitation s’inspirant des récents travaux méthodologiques sur l’ACV conséquentielle. L’application pratique de cette nouvelle approche « conséquentielle-projet » nécessite la production de connaissances mobilisant l’ACV dynamique et l’ACV prospective.Concrètement, la thèse propose une modélisation dynamique du fonctionnement du système électrique dans un cadre « type » affranchi des aléas climatiques et économiques. Le modèle sert de base au développement de méthodes d’évaluation originales des impacts de l’électricité : une méthode dynamique moyenne et une méthode marginale. Ces méthodes améliorent la précision d’une étude d’analyse de cycle de vie, quel que soit l’objectif (certification ou écoconception) et l’approche méthodologique associée (attributionnelle ou conséquentielle-projet).La thèse propose ensuite l’intégration de scénarios prospectifs adaptés à l’étude des bâtiments et des quartiers. Celle-ci associe les recherches en prospective énergétique menées à l’échelle nationale et les recherches concernant l’impact du changement climatique sur le comportement thermique des bâtiments. Les effets conjoints de ces deux déterminants sont évalués au sein d’une approche originale et intégrée.La thèse explore également la question du changement d’échelle du bâtiment vers le quartier. Les cas du transport des occupants et du traitement des déchets sont analysés au prisme de l’approche « conséquentielle-projet ». Une méthodologie de couplage des outils de simulation transport au niveau local et de l’ACV est notamment proposée. Elle constitue un premier pas vers un couplage interdisciplinaire des outils d’analyse des projets urbains.Les différents développements méthodologiques sont finalement appliqués à une étude de cas afin d’analyser et d’interpréter l’effet des nouvelles approches sur l’aide à la décision fournie par les outils d’écoconception. / Environmental impacts induced by urban projects concern various topics (resources, health, biodiversity). Some are indirect impacts (for instance radioactive waste generated by electricity consumption). This calls for a holistic and multicriteria approach such as Life-Cycle-Analysis (LCA) in order to evaluate environmental performance of construction or retrofitting projects. Considering cradle to grave impacts this method is used at different project phases: program objectives, design aid, management strategies evaluation, retrofitting project, dismantling, and waste management.The thesis lies in the framework of life-cycle analysis applied to urban project design, from individual houses up to multifunctional neighborhoods. The underlying objective is to improve relevance and accuracy of the decision aid provided by LCA-based design tools.Three interacting topics have been investigated:- Consequential assessment: How can the results of current research on consequential LCA be implemented in Building LCA?- Dynamic: How to integrate dynamic interaction between buildings and the background system, mainly the electricity grid?- Prospective: How to take into account the long life span of buildings and urban districts?The dissertation firstly suggests a new framework for evaluating construction or retrofitting project, grounded in consequential LCA. The practical application of this consequential-project approach requires knowledge generation on dynamic and prospective LCA.A dynamic model of the electricity system has been developed. From this model, a reference operation year of the electricity system has been determined, mitigating climatic and economical hazards of real years. Based on this model, a dynamic average approach and a marginal approach are defined to assess life-cycle impacts of electricity consumption. These developments improve the accuracy of LCA independently of the chosen modeling approach, consequential or attributional.The prospective dimension is explored, through scenarios development. The suggested scenarios bring together national energy prospective research and global warming effects on buildings thermal behavior. The combined effects are evaluated using a novel and integrated approach.The thesis then addresses the scale issue when moving from building to district projects. Following the consequential-project approach principles, the focus is made on integrating daily transport and domestic waste models in LCA of urban projects. A method to combine local transport simulation models and building LCA is suggested. It establishes a first step towards integrated multidisciplinary assessment of urban projects.The developed approaches and methodologies are finally tested on a case study.
78

Posuzování životního cyklu komunálního odpadu / Life cycle assessment of municipal waste

Vlach, Josef January 2008 (has links)
The aim of this study is to present methodology life cycle (LCA) and Life Cycle Assessment of disposal the municipal solid waste chain. There is described the procedure of generation of the LCA studies according to the standards ČSN EN ISO 14 040 and ČSN EN ISO 14 044 in the first and second part. In the third part of this diploma there are described LCA analyses that have already been created. The software GEMIS (Global Emission Model for Integrated System) is described in the fourth part. The computer model GEMIS has been used as a calculation tool in this study. The fifth part of this study includes waste management and different kinds of disposal municipal solid waste. In this part is describe basic data about landfilling and incieration. There is shown LCA analysis of disposal municipial solid waste in the sixth part. Data processing was carried out by means of the software GEMIS 4.3. The results were interpreted for incineration and landfilling. Finally there is mentioned results for 1 TJ different elektrical energize to.
79

Potentiella miljövinster inom anläggningssektorn sett ur ett livscykelanalysperspektiv : Genomförande och utvärdering av en livscykelanalys på en vägsektion / Potential environmental profits in the construction sector from a life cycle analysis perspective

Wallsten, Johan January 2022 (has links)
Bygg och anläggningssektorn står för en stor del av Sveriges totala miljöpåverkan. År 2021 stod sektorn för 21 % av Sveriges totala utsläpp av växthusgaser, vilket efter inrikes transporter är störst i Sverige. Efter att IVA och Sveriges Byggindustrier släppte en rapport år 2014, infördes en lag 2022 där krav ställdes på klimatdeklaration för nya byggnader. Även om samma krav inte än gäller för anläggningssektorn, har Upphandlingsmyndigheten publicerat klimatkrav 2021 som kan användas vid upphandlingar av anläggningsprojekt. Företag inom branschen räknar också med att hållbarhetskrav kommer ställas för de flesta anläggningsprojekt inom en snar framtid.  För att få en bild av ett projekts totala miljöpåverkan, används ofta metodiken hos en livscykelanalys. Livscykelanalys, även kallat LCA, är ett verktyg som beräknar miljöpåverkan under en produkts, ett systems eller ett materials hela livscykel, från vagga till grav. Det kan användas för att se i vilket skede av ett projekts livscykel miljöpåverkan är som störst och vilka ingående material/massor/produkter som är värst sett ur en miljösynpunkt. Miljöpåverkan innefattar en rad olika faktorer såsom försurning och eutrofiering, dock läggs fokus på global uppvärmningspotential (GWP) i den här rapporten. Resultatet kan sedan användas för att projektera och bygga med mindre miljöpåverkan. Det här projektet syftar till att göra en livscykelanalys på ett genomfört vägbygge i ett tätbebyggt område. Vägbygget består av vägkroppen med tillhörande gång- och cykelbana samt VA-ledningar. En genomsnittlig vägsektion på 100 m valdes ut från projektet, som skalades upp 10 gånger till 1 km för att kunna jämföras med andra studier där den funktionella enheten var densamma. Livslängden på vägen sattes till 100 år, där de olika ingående delarnas livslängd i vägen varierade. Beräkningarna utgick från en mängdförteckning över projektet med ingående mängder, och beräkningsprogrammet som användes var One Click LCA.  Resultatet av projektet visade på att markförstärkning med kalk-cementpelare (KC) var värst sett ur en miljösynpunkt. När KC-pelare inklusive användningen av KC-pelarmaskin under byggfasen inkluderades ökade projektets totala miljöpåverkan med ca 200 %, och orsakade 1437 ton CO2 -Ekvivalenter av 2167. Utan markförstärkning var projektet ansvarigt för 729 ton CO2-Ekvivalenter i utsläpp. När KC-pelare exkluderades utgjorde asfaltmaterialet 41 % av projektets totala miljöpåverkan. Om resultaten från studien ska kopplas till Upphandlingsmyndigheten krav från 2021 syns det tydligt att störst miljövinster kan göras tidigt i projektering genom uppförande av livscykelanalys, samt att välja rätt val sett ur en miljösynpunkt. Bara genom att använda en grön asfalt till slitlagret kan projektets miljöpåverkan minska från 729 ton till 660 utan markförstärkning, en minskning med 9 %. Resultaten visar på att konstruktionsfasen A1-A3 orsakade störst miljöpåverkan, där stora möjligheter till förbättring finns.  Fortsatt undersökning skulle behöva inkludera kostnadsaspekten, då även om ett material är bättre ur en miljösynpunkt kan det vara ekonomiskt oförsvarbart att välja det. Inom projektets systemgränser exkluderades bland annat trädplantering och vegetationsförberedning. Dessa kan ha en positiv inverkan på projektets totala miljöpåverkan då träd kan lagra koldioxid under sin livslängd, och marken kan användas som biobädd alternativt inkludera biokol. / The building- and construction sector accounts for a large amount of Sweden’s total environmental impact. The year 2021 it was responsible for 21 % of Sweden’s total emission of GHG:s, which is the second largest sector after domestic transport. After a report made by IVA and Sveriges Byggindustrier was released 2014, a new law was enacted where the construction of new buildings had to be climate declared, with small exceptions. Even if the same demands don’t apply for the building- and construction sector, the Procurement Authority published climate requirements to be used in procurement’s and design. Companies within the business is counting on that climate requirements will be mandatory within construction projects in a near future.  To get a picture of a projects total environmental impact, a life cycle analysis is often used. Life cycle analysis, in short LCA, is a tool to calculate the environmental impact of a project/material/product from cradle to grave. It can be used to see hot-spots where a projects life cycle has the largest environmental impact. Environmental impact includes a number of factors like acidification and ozone depletion potential, although focus will be on global warming potential (GWP) in this study. The results can be used to plan and build with a reduced environmental impact.  The aim with this study was to make a life cycle analysis on a implemented road construction in a densely populated area. The analysis includes a walk- and cycle-path and water and sewage pipes beneath the road. An average road-section of 100 m was chosen from the project, where it was scaled up 10 times to easier be compared with previously conducted studies. The service life was set to 100 years, where the service life for the components in the road varied. The calculations originated from a quantity list from the project, and the calculation program used was One Click LCA.  The results from the project showed that ground reinforcement with lime cement pillars was worst from an environmental standpoint. The inclusion of ground reinforcement increased the projects total environmental impact with approximately 200 %, and was responsible for 1437 ton CO2-Equivalents of a total of 2167. Without ground reinforcement the projects total environmental impact was 729 ton CO2-Equivalents. Asphalt showed to be the most contributing part in the project, with 41 % of the projects total environmental impact.  If the results of the study is to be linked to the demands of the Procurement Authority from 2021, it is clear that environmental profits can be made early in the design phase. By making a LCA, the right choice can be made from an environmental standpoint. Just by choosing Green asphalt on the wear layer of the road, the environmental impact can be lowered 9 % while ground reinforcement is excluded. The results shows clearly that the construction phase A1-A3 caused the greatest environmental impact, and had great possibilities for improvement within the chain.  Regarding future investigations, the cost aspect need to be included. Even if a material is better seen from an environmental standpoint, it can be economically indefensible to choose it. Within the projects system boundaries planting of trees and vegetation was excluded, which could have a positive effect on the projects total environmental impact.
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Servicing or Buying New? Estimating the Environmentally Optimal Time for Car Replacement in Sweden – an LCA Approach.

Wissert, Larissa Patricia January 2022 (has links)
Purpose. Road transportation is one of the major sources of GHG emissions today. Technological improvements in fuel consumption, as well as the electrification of vehicles can reduce emissions from road transportation. This study aims to investigate the optimal time for vehicle replacement in Sweden for an ICEV to minimise GHG emissions. While many LCA studies compare the total emissions from ICEVs with BEVs and conduct a break-even analysis, little focus is dedicated to the implications of the results. Previous studies did not estimate the time of vehicle replacement at which GHG emissions are minimised. To represent the Swedish vehicle fleet, the optimal replacement time is estimated for a Volvo V70 (petrol, 2011 model), when replacing it with a Volvo V60 (petrol, 2020 model) (Scenario 1), correspondingly when replacing with a Polestar 2 (battery-electric, 2020 model) (Scenario 2). Methods. For the estimation of lifetime emissions resulting from the three vehicle models, a Life Cycle Analysis was conducted. The functional unit investigated was 200.000 km driven with the V70, the V60 and Polestar 2, assuming that the vehicles were operated in Sweden. The emission values are then used to model the vehicle replacement in each scenario and the results are analysed. Findings. The LCA study showed that the V70 emits 64,08 tCO2eq. over its total lifespan, the V60 46,48 tCO2eq., and the Polestar 2 29,05 tCO2eq. The study showed that there is not one optimal replacement time, but the optimal time for vehicle replacement, from a carbon emission point of view, is inherently linked to the total driven mileage and number of cars owned. However, the trend shows that the time of replacement in Scenario 1 should be close to the End-of-Life of the V70. For Scenario 2 it is beneficial to replace the V70 immediately.

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