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<b>Sustainability Analysis of Critical Materials in Electric Vehicles with Emphasis on Circular Economy Principles</b>Thomas Maani (19207021) 27 July 2024 (has links)
<p dir="ltr"><a href="" target="_blank">The electrification of the transportation sector is pivotal in reducing greenhouse gas emissions and decreasing dependence on fossil fuels. Central to this transition are battery electric vehicles (BEVs) and other clean energy technologies, which rely heavily on critical materials (CMs) such as cobalt, lithium, neodymium, and nickel. </a>These materials are essential for the performance of batteries, advanced electronics, and other components in BEVs. <a href="" target="_blank">However, the limited availability of these CMs poses potential constraints on the widespread adoption of such technologies.</a></p><p dir="ltr">This research delves into the implications of widespread BEV adoption on the demand for CMs in the United States, with a focus on both light-duty vehicles (LDVs) and medium- and heavy-duty vehicles (MHDVs). Various market penetration scenarios were analyzed, revealing that while MHDVs require more CMs per vehicle, the sheer volume of LDV sales drives the overall CM demand, particularly in a scenario with 100% BEV adoption. Key findings highlight that cobalt, graphite, lithium, neodymium, and nickel are critical for BEVs, whereas palladium and rhodium are more crucial for internal combustion engine vehicles (ICEVs). Also explored is the impact of lightweighting on LDVs, revealing that while substituting steel with aluminum increases the total CM quantity per vehicle, it reduces the vehicle's mass, operational energy consumption, and the demand for high-concern battery-related CMs. Additionally, changing the battery cathode chemistry from NMC622 to LFP significantly reduces CM use but increases the demand for strategic materials like copper and phosphorus due to the lower energy density of LFP-based batteries.</p><p dir="ltr">The research also highlights the importance of rare earth permanent magnets (REPMs), <a href="" target="_blank">particularly Neodymium-Iron-Boron (NdFeB) magnets, in clean energy technologies such as electric vehicles and wind turbines.</a> Neodymium, a critical material, faces supply chain risks. To lessen these risks, circular economy strategies have been proposed, including the recovery of needed materials from end-of-life (EoL) products. <a href="" target="_blank">A dynamic material flow analysis (MFA) model was developed to forecast such EoL flows for products containing REPMs and assess the recoverable neodymium from these EoL products. </a>The results indicate that even a modest recycling efficiency of 15% could meet 12% of the Nd demand for EVs by 2050, with reuse meeting up to 70% of the demand.</p><p dir="ltr">With the dynamic MFA model showing that circular economy principles could meet up to 70% of future neodymium demand in 2050, the next step was to investigate the techno-economic feasibility of recycling REPMs. A techno-economic assessment model was developed for establishing a magnet-to-magnet recycling facility for REPMs. Results revealed a net present value (NPV) of $8,867,111 over 20 years, a payback period of 3 years, and an internal rate of return (IRR) of 53%, providing a compelling case for investment in recycling infrastructure. Sensitivity analyses point to the selling price of recycled magnets, feedstock purchase price, facility throughput, and labor costs as the most influential factors on profitability.</p><p dir="ltr"><a href="" target="_blank">Additionally, this research explored the challenges and opportunities in the disassembly and recycling of EoL EV components, particularly traction motors containing REPMs. The complexity of disassembly, driven by varying component sizes and designs, is identified as a significant barrier. By evaluating manual disassembly times and proposing potential automation solutions, the study aims to streamline the disassembly process, thus facilitating more efficient recycling and remanufacturing operations.</a></p><p dir="ltr">The key contributions of this research are summarized as follows:</p><p dir="ltr">· Evaluated the vehicle CM demand of ICEVs and BEVs for LDVs and MHDVs and explored the impact of lightweighting and changing the battery cathode chemistry from NMC622 to LFP on CM demands.</p><p dir="ltr">· Developed a dynamic material flow analysis (MFA) model to forecast end-of-life (EoL) flows of products containing REPMs and assess the recoverable neodymium from these EoL products.</p><p dir="ltr">· Developed a techno-economic assessment (TEA) model to evaluate the viability of a magnet-to-magnet recycling facility.</p><p dir="ltr">· Performed disassembly analysis to assess the ease with which EoL BEV transmissions can be disassembled with a specific focus on the retrieval of traction motors (which house the REPMs) for potential reuse or remanufacturing.</p>
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<b>OPTIMIZATION STRATEGIES OF A PARAMETRIC PRODUCT DESIGN </b><b>FOR A CIRCULAR ECONOMY WITH APPLICATION TO AN </b><b>ELECTRIC TRACTION MOTOR</b>Jesús Pérez-Cardona (17501118) 01 December 2023 (has links)
<p dir="ltr">In our daily lives, we rely on a multitude of discrete products to meet our needs. Traditional product design approaches have primarily focused on economic and technical aspects, often overlooking the pressing environmental and social challenges facing society. Recognizing the limitations of our ecological systems to cope with the waste generated by our current industrial processes, there is a growing need to anticipate the potential consequences of product design across technical, economic, environmental, and social dimensions to pave the way for a sustainable future. One promising strategy within this context is the integration of sustainability principles into optimization-based design models that consider a product's entire life cycle. While there have been previous efforts to optimize product life cycles, a comprehensive exploration of optimization-based design methods with a focus on multiple objectives for discrete products is essential. This dissertation explores the integration of sustainability principles with optimization-based design by taking the electric traction motor used in electric vehicles as a case study. This complex and environmentally significant technology is ideal for investigating the tradeoffs and benefits of incorporating sustainability objectives into the design process.</p><p dir="ltr">The key tasks undertaken in this study are as follows:</p><ul><li>Development of a parametric design and optimization framework for a surface-mounted permanent magnet synchronous motor. In this task, a special emphasis is placed on reducing reliance on materials with a high supply risk, such as rare earth elements.</li><li>Creation of a parametric life cycle assessment model that combines life cycle assessment and optimization-based design to minimize a single-score environmental impact. This model offers insights into the environmental performance of product design and underscores the importance of minimizing environmental impact throughout a product's life cycle.</li><li>Integration of a life cycle costing model, incorporating techno-economic assessment and total cost of ownership perspectives, into the parametric life cycle assessment and optimization-based design models. This model is used to minimize levelized production and driving costs, shedding light on the trade-offs within this family of cost metrics and the optimization of manufacturing systems for motor production.</li><li>Proposal of a circular economy model/algorithm to assess the advantages of integrating the circular economy paradigm during the early design phase. All the mentioned objective functions are considered to study the impacts of applying the circular economy paradigm.</li></ul><p dir="ltr">The contributions of this research can be summarized as follows:</p><ul><li>Utilized a diverse array of analytical methodologies to parameterize the design process of a motor, incorporating the integration of Life Cycle Assessment (LCA) and Techno-Economic Analysis (TEA) models, as well as the incorporation of disassembly planning for informed decision-making in the early stages of design.</li><li>Proposed a generalized objective function denoted as the Supply Risk-equivalent (SR-eq.), aimed at mitigating the risks associated with the dependency on critical materials in product manufacturing.</li><li>Introduced a novel approach for visualizing non-dominated solutions within a multi-objective framework, with experimentation conducted on up to six distinct objectives.</li><li>Substantiated the significance of decarbonizing the electric grid while maintaining competitive cost structures, the importance of advancing non-destructive evaluation (NDE) procedures for assessing the condition of end-of-life (EoL) subassemblies, and optimizing the collection rate of EoL motors.</li></ul><p dir="ltr">Demonstrated that the optimization of technical metrics as surrogate indicators for economic and environmental performance does not necessarily yield designs that are concurrently optimal in economic and environmental terms.</p>
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Performance characterisation of duplex stainless steel in nuclear waste storage environmentOrnek, Cem January 2016 (has links)
The majority of UK’s intermediate level radioactive waste is currently stored in 316L and 304L austenitic stainless steel containers in interim storage facilities for permanent disposal until a geological disposal facility has become available. The structural integrity of stainless steel canisters is required to persevere against environmental degradation for up to 500 years to assure a safe storage and disposal scheme. Hitherto existing severe localised corrosion observances on real waste storage containers after 10 years of exposure to an ambient atmosphere in an in-land warehouse in Culham at Oxfordshire, however, questioned the likelihood occurrence of stress corrosion cracking that may harm the canister’s functionality during long-term storage. The more corrosion resistant duplex stainless steel grade 2205, therefore, has been started to be manufactured as a replacement for the austenitic grades. Over decades, the threshold stress corrosion cracking temperature of austenitic stainless steels has been believed to be 50-60°C, but lab- and field-based research has shown that 304L and 316L may suffer from atmospheric stress corrosion cracking at ambient temperatures. Such an issue has not been reported to occur for the 2205 duplex steel, and its atmospheric stress corrosion cracking behaviour at low temperatures (40-50°C) has been sparsely studied which requires detailed investigations in this respect. Low temperature atmospheric stress corrosion cracking investigations on 2205 duplex stainless steel formed the framework of this PhD thesis with respect to the waste storage context. Long-term surface magnesium chloride deposition exposures at 50°C and 30% relative humidity for up to 15 months exhibited the occurrence of stress corrosion cracks, showing stress corrosion susceptibility of 2205 duplex stainless steel at 50°C.The amount of cold work increased the cracking susceptibility, with bending deformation being the most critical type of deformation mode among tensile and rolling type of cold work. The orientation of the microstructure deformation direction, i.e. whether the deformation occurred in transverse or rolling direction, played vital role in corrosion and cracking behaviour, as such that bending in transverse direction showed almost 3-times larger corrosion and stress corrosion cracking propensity. Welding simulation treatments by ageing processes at 750°C and 475°C exhibited substantial influences on the corrosion properties. It was shown that sensitisation ageing at 750°C can render the material enhanced susceptible to stress corrosion cracking at even low chloride deposition densities of ≤145 µm/cm². However, it could be shown that short-term heat treatments at 475°C can decrease corrosion and stress corrosion cracking susceptibility which may be used to improve the materials performance. Mechanistic understanding of stress corrosion cracking phenomena in light of a comprehensive microstructure characterisation was the main focus of this thesis.
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Les interprètes de la Convention de Genève du 28 juillet 1951 relative au statut des réfugiés : Étude du point de vue de la France / The Interpreters of the Geneva Convention of 28 July 1951 relating to the Status of Refugees : A Study from the point of view of France.Castillo, Justine 27 May 2016 (has links)
Plus de soixante ans après son adoption, la Convention de Genève compte 145 États parties.Instrument juridique universel sur le statut des réfugiés, elle est la lex specialis du droit international desréfugiés. Qui est réfugié ? Quelle protection lui est accordée ? Ces deux questions se posent avec uneacuité certaine du fait de l’accroissement des flux migratoires, des crises multiples et de la lutte contre leterrorisme. Le contexte actuel de l’application de la Convention est différent de celui de son adoption.Rédigée par la voie de dispositions générales, elle doit être interprétée pour être appliquée. Cependant, iln’existe pas un interprète. Si les États, le Haut Commissariat des Nations Unies pour les réfugiés et laCour internationale de justice sont les interprètes officiels, ils ne sont pas les seuls. L’Office français deprotection des réfugiés et apatrides et la Cour nationale du droit d’asile jouent un rôle important et la Coureuropéenne des droits de l’homme et la Cour de justice de l’Union européenne jouent un rôle grandissant.Cette multiplicité d’interprètes peut causer une diversité d’interprétations. Or, les interprétationsdivergentes nuisent à la lisibilité et la visibilité de la Convention en tant qu’instrument de définition et deprotection des réfugiés. La présente étude est une analyse de la contribution des interprètes aux évolutionsde la Convention. Dans cette perspective, la prolifération des instruments du droit européen etinternational des droits de l’homme et la complexification des déplacements contraints de personnes sontdes paramètres incontournables, pris en compte par les interprètes, pour éclairer le sens et la portée de laConvention. / More than sixty years after its adoption, the Geneva Convention counts 145 States ascontracting Parties. This universal legal instrument on refugee’s status represents the lex specialis ofinternational refugee Law. Who can be a refugee? What can be his level of protection? These questionsare particularly relevant under the influence of the increasing population flows, the multiples crises andthe fight against terrorism. The current context of the Convention’s application is different than the one ofits adoption. And due to its general provisions, this Convention needs to be interpreted in order to beapplied. However, there is no sole interpreter. The States, the United Nations High Commissioner forRefugees and the International Court of Justice are indeed the official interpreters, but not the only onesensuring this mission. Not only the French Office for the Protection of Refugees and Stateless Persons andthe National Court of Asylum play an important role in this matter, but the European Court of HumanRights and the Court of Justice of the European Union also play an expanding role. This multiplicity ofinterpreters can induce a variety of interpretations. Nevertheless, a divergent interpretation can affect thereadability and the visibility of the Convention as a refugee defining and protective legal instrument. Thepresent study constitutes an analysis of the interpreters’ contribution to the Convention’s developments. Inthis perspective, the overgrowth of European and International Human Rights Law instrument and thecomplexity of forced migration are ineluctable feature, taken into account by the interpreters, to clarify themeaning and the scope of the Convention.
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Implementeringen av koldioxidsnåla och klimatpositiva benchmarks samt ESG-relaterad transparens i BMR : en kritisk granskning av kommissionens föreslagna ändringar av Benchmarkförordningen och dess förenlighet med de åsyftade ändamålen / The implementation of low carbon & positive carbon impact benchmarks and ESG transparency in the BMR : a critical review of the Commission's proposed changes to the Benchmark regulation and its comparability with the intended objectivesBotshinda, Amelia January 2020 (has links)
Vi lever i en tid präglad av drastiska klimatförändringar och ökade utsläpp av växthusgaser, där klimatångest har kommit att bli ett problem som tycks drabba såväl privatpersoner som företag. Allteftersom vår medvetenhet för samtidens klimathot ökar, har även hållbarhet fått en allt större betydelse för europeiska investerare. En tydlig konsekvens härav är den kraftiga ökningen av antalet hållbarhetsindex som identifierats på finansmarknaden. Hållbarhetsindex används ofta som komponent i passiva investeringsstrategier eller som verktyg för att mäta prestationen av olika värdepapper i en portfölj, och får på så vis funktionen av ett benchmark. Metoden för att utveckla såväl hållbara index som benchmarks kan emellertid variera, vilket ofta beror på att klimatrelaterad information kan vara extremt komplex att omvandla till finansiellt relaterbara värden. Svårigheterna härom har således minskat marknadens förtroende för sådana investeringsalternativ, trots den ökade benägenheten hos investerare att ta hänsyn till hållbarhet även i finansiella sammanhang. Bristande lagstiftning inom området föranledde Europeiska kommissionen att upprätta ett förslag om ändring av Benchmarkförordningen år 2018, som en del av sin handlingsplan för finansiering av hållbar tillväxt. Förordningen reglerar i dagsläget främst administratörer av benchmarks, vilka innehar det övergripande juridiska ansvaret för ett benchmark. Med förslaget införs nya kategorier för koldioxidsnåla och klimatpositiva benchmarks samt en reviderad transparensreglering som förpliktigar administratörer att offentliggöra hur de beaktar hållbarhet i sin metod och referensvärdesdeklaration. Även om förslaget välkomnats av flertalet aktörer, föreligger anledning att ifrågasätta huruvida marknaden kommer kunna förhålla sig till de ambitiösa ändringarna, samt om effekten av reglerna blir den som kommissionen eftersträvat. I uppsatsen identifieras och diskuteras de potentiella utmaningarna med förslagets ikraftträdande, vilka sedermera analyseras i förhållande till de åsyftade ändamålen med reglerna. Kritik riktas i uppsatsen främst mot förordningens bristande möjligheter att hålla andra aktörer ansvariga, eftersom uppfyllandet av de nya reglerna inte enbart är beroende av administratörernas eget agerande. Vidare konstateras att marknaden inledningsvis kommer att få stora svårigheter med insamling och verifiering av den klimatrelaterade information som är avgörande för användningen av miljövänliga benchmarks. Sett ur ett långsiktigt perspektiv tros emellertid ändringarna kunna skapa goda förutsättningar för en bättre inkludering av hållbarhet på finansmarknaden, utan kompromiss av ett konsument- eller investerarskydd.
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Extern granskning av gröna obligationer : Huruvida regulatoriska förändringar vad gäller betygsättning av gröna obligationer kan gynna marknaden för gröna obligationer / External review of green bonds : Whether regulatory changes in the rating of green bonds can benefit the green bond marketLindgren, Jessica January 2021 (has links)
Genom styrning av finansiella medel har gröna obligationer fått en viktig roll i utvecklingen mot ett miljömässigt hållbart samhälle. Extern granskning av gröna obligationer styrs idag genom frivilliga marknadsstandarder, varav GBP är den vanligaste. Dessutom har EU nyligen presenterat en egen frivillig standard med särskild tillsyn. Bättre tillgång till klimatrelaterad information samt tydliga och gemensamma definitioner av gröna aktiviteter är förutsättningar för att investerare mer effektivt ska flytta kapital till miljömässigt hållbara verksamheter för att stötta omställningen till en mindre fossilbaserad ekonomi. I den här uppsatsen visas att dagens betygsättning, olika bedömningsmetoder till trots, torde vara relativt pålitlig, men att det finns utrymme att önska högre jämförbarhet och därmed ökad investerartillit. Tydligare marknadsstandarder kan vara en viktig aspekt för att öka betygens pålitlighet allt eftersom marknaden för gröna obligationer expanderar. Analysen visar att lagstiftning som leder till ökad mängd publicerad granskning genom gröna betyg torde gynna transparensen samtidigt som ryktesrisken vid intressekonflikter bör innebära motvillighet gentemot felaktig bedömning. Samtidigt kan överdriven reglering begränsa möjligheterna för innovation, utveckling och expansion av marknaden som helhet. Det torde därmed vara i lagstiftarens intresse att inte införa alltför sträng reglering, eftersom risk att inte kunna uppnå den finansiering av klimatmålen som önskas då uppstår. Eftersom gröna obligationer är ett internationellt fenomen behöver världens länder arbeta tillsammans mot gemensamma standarder i syfte att nå klimatmålen. I det fall tvingande reglering ska införas bör den vara på som lägst EU-nivå. För marknadsbalans mellan aktörerna och jämförbarhet mellan obligationerna är det viktigt att regleringen inte upplevs otydlig. Regleringen måste dessutom vara generell och så pass flexibel att den kan möta teknologisk utveckling och förändrade förhållanden på marknaderna utan att processen blir för långdragen. Så länge målet är att ha en europeisk kapitalmarknad där aktörerna kan tillhandahålla finansiella tjänster nationsövergripande krävs finansiell tillsyn som inte stannar vid nationsgränserna. På sikt torde Esma vara lämpligast att överse samtliga granskare av gröna obligationer verksamma på den europeiska marknaden. För detta krävs utökad reglering som ger Esma ökad behörighet såväl som ökade resurser för att effektivt kunna utföra tillsynsarbetet. / Through the management of financial resources, green bonds have received an important role in the development towards an environmentally sustainable society. External review of green bonds is today subject to voluntary market standards, of which GBP is the most common. In addition, the EU has recently presented its own voluntary standard, which includes supervision. Better access to climate-related information and clear and harmonised definitions of green activities are prerequisites for investors to move capital more efficiently to environmentally sustainable businesses to support the transition to a less fossil-based economy. With this paper it is shown that the current rating, despite different assessment methods, should be relatively reliable, but that there is room to wish for higher comparability and thus increased investor confidence. Clearer market standards can be an important aspect in increasing the reliability of ratings as the market for green bonds expands. The analysis shows that legislation that leads to an increased number of published reviews through green ratings should promote transparency, while the risk of rumors in the event of conflicts of interest should imply reluctance to make incorrect assessments. At the same time, excessive regulation may limit the opportunities for innovation, development and expansion of the market as a whole. Thus, it should be in the interest of the legislator not to introduce a regulation which is too strict, as the risk of not being able to achieve the desired financing of the climate goals then arises. As green bonds are an international phenomenon, all countries need to work together towards common standards in order to achieve the purpose of the climate goals. In the event that mandatory regulation is to be introduced, it should at least be at EU level. For market balance between the market participants as well as comparability between the bonds, it is important that the regulation is not perceived as unclear. In addition, regulation must be general and flexible enough to meet technological developments and new market conditions without the process becoming too lengthy. As long as the goal is to have a European capital market where market participants can provide financial services nationwide, financial supervision that does not stop at national borders is required. In the long run, ESMA should be the most appropriate authority to oversee all examiners of green bonds operating in the European market. This requires increased regulation that gives ESMA increased authority, as well as increased resources in order to be able to carry out the supervisory work effectively.
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