Le bâtiment est considéré comme étant le premier secteur consommateur d’énergie dans le monde. Dans la région méditerranéenne, face à la crise économique et aux engagements pris pour limiter les effets produisant le réchauffement climatique, il est devenu impératif de réduire la consommation énergétique des bâtiments que ce soit par la conception des bâtiments neufs ou par la réhabilitation du parc existant. Dans ce cadre-là, chercher des solutions techniques optimales en tenant compte des critères économiques, environnementaux et sociétaux est un problème très complexe du fait du nombre élevé de paramètres à prendre en compte. Pour remédier à ce problème, un état de l’art des méthodes d’optimisation multicritère a été réalisé. Nous avons constaté que plusieurs contraintes existent lors de l’utilisation de ces méthodes telles qu’un temps de calcul élevé et la non-maîtrise de la convergence des résultats vers des optimums globaux recherchés. L’objectif de notre travail est de proposer une nouvelle méthode qui permette de contourner ces difficultés. Cette méthode est basée, dans un premier temps, sur le développement des modèles polynomiaux pour la prédiction des besoins de chauffage, de refroidissement, d’énergie finale et du confort thermique d’été à l’aide du logiciel TRNSYS. Pour établir ces modèles, nous avons utilisé la méthode des plans d’expériences et des simulations thermiques dynamiques. À partir de ces modèles, une analyse de sensibilité a été entamée afin d’identifier les paramètres les plus influents sur les besoins énergétiques et le confort thermique d’été. Une base de données est utilisée associant chaque paramètre à son coût et à son impact environnemental sur son cycle de vie. Ensuite, une étude paramétrique complète a été réalisée en utilisant les fonctions polynomiales dans le but de déterminer un ensemble de solutions optimales à l’aide de l’approche du Front de Pareto. Cette nouvelle méthode a été appliquée dans le but de concevoir des bâtiments neufs à haute efficacité énergétique à des coûts maîtrisés pour les six zones climatiques du Maroc. La validation des modèles polynomiaux réalisée grâce à une comparaison avec des simulations aléatoires a donné des résultats très satisfaisants. Avec un modèle polynomial de second degré, l’erreur maximale sur les besoins énergétiques et le confort thermique adaptatif d’été ne dépasse pas 2 kWh/m².an et 9% respectivement dans la plupart des cas. Les modèles développés ont ensuite été utilisés pour l’aide à la décision multicritères. Les résultats obtenus ont montré que des bâtiments à très faibles besoins énergétiques peuvent être construits à un coût raisonnable, et qu’un effort doit être porté sur des solutions plus performantes pour le rafraîchissement en été. Enfin, nous avons mis en œuvre la méthode que nous avons développée dans le cadre de la réhabilitation d’un bâtiment existant à La Rochelle. Les critères environnementaux ont aussi été intégrés à la recherche de solutions optimales. La solution retenue selon 14 critères correspond à un ensemble de solutions techniques permettant d’obtenir des besoins de chauffage de l’ordre de 15 kWh/m².an avec un compromis réalisé entre l’efficacité énergétique, le confort des occupants, les impacts environnementaux et la maîtrise du coût de la réhabilitation. La méthode développée dans le cadre de ce travail a montré un fort potentiel d’utilisation pour l’aide à la décision multicritère lors de la conception des bâtiments neufs ou en réhabilitation. Elle permet d’effectuer très rapidement une optimisation opérationnelle de l’enveloppe pour contribuer à des bâtiments durables, confortables, à coût maîtrisé et à basse consommation énergétique. / The building sector is the largest consumer of energy in the world. In Mediterranean region, facing the economic crisis and commitments for climate change, the reduction of energy consumption for both new and existing buildings is more necessary. Against this background, seeking optimal technical solutions taking into account the economic, environmental and societal criteria is a very complex problem due to the high number of parameters to consider. In order to solve this problem, a state of the art of multi-criteria optimization method has been achieved. We found that many constraints exist when using these methods such as high time calculation and no absolute assurance to find the global optimum. Thus, the main objective of the present work is to propose a new method that allows overcome these difficulties. This method is based on the development of polynomial models for the prediction of heating energy needs, cooling energy needs, final energy needs and summer thermal comfort. To establish these models, we used the design of experiments method and dynamic thermal simulations using TRNSYS software. From these models, a sensitivity analysis has been achieved in order to identify the leading parameters on energy requirements and thermal comfort in summer. A database associating each parameter for its cost and environmental impact on its lifetime was generated from CYPE software and INIES database. Then, a detailed parametric study was performed using polynomial functions for determining a set of optimal solutions using the Pareto front approach. This new method was applied to design new buildings with high energy efficiency at controlled costs for the six Moroccan climate zones. The validation of polynomial models through a comparison with random simulations gave very satisfactory results. With a polynomial model of the second order, the maximum error on the energy needs and the adaptive thermal comfort did not exceed 2 kWh/m².an and 9% respectively. The developed models were used for multiple-criteria decision analysis. The results showed that buildings with very low energy needs can be built with a reasonable cost. On the other hand an effort should be focused on more efficient solutions for adaptive thermal comfort in summer especially for Marrakech and Errachidia. Finally, we also implemented our method to a project of energy rehabilitation of an existing building located in La Rochelle (France). Environmental criteria were also taken into account in the optimization process. The selected technical solutions procured approximately 15 kWh/m².year of heating energy needs. The developed multicriteria decision method showed a great potential for both designing new and existing buildings with high energy efficiency. It allows a very fast operational optimization of sustainable buildings at reasonable cost and low energy consumption.

Submitted by Marcia Silva (marcia@latec.uff.br) on 2016-10-19T18:23:01Z No. of bitstreams: 1 Dissert Pedro Paulo Silveira Felicíssimo.pdf: 2519035 bytes, checksum: 23d5c78d7f6eb64ebc2c2ea24e489d84 (MD5) / Rejected by Biblioteca da Escola de Engenharia (bee@ndc.uff.br), reason: Favor acertar o nome do autor na ficha catalográfica e incluir folha de rosto. Atenciosamente, Catarina Ribeiro Bibliotecária BEE - Ramal 5992 on 2017-01-27T10:56:25Z (GMT) / Submitted by Marcia Silva (marcia@latec.uff.br) on 2017-02-08T17:37:49Z No. of bitstreams: 1 Dissert Pedro Paulo Silveira Felicíssimo.pdf: 2519035 bytes, checksum: 23d5c78d7f6eb64ebc2c2ea24e489d84 (MD5) / Rejected by Biblioteca da Escola de Engenharia (bee@ndc.uff.br), reason: Favor incluir no trabalho a folha de rosto (elemento obrigatório), antes da ficha catalográfica. Obs.: Na ficha catalográfica, o nome do autor está incompleto. Atenciosamente, Catarina Ribeiro Bibliotecária BEE - Ramal 5992 on 2017-02-15T11:58:04Z (GMT) / Submitted by Marcia Silva (marcia@latec.uff.br) on 2017-05-09T19:55:21Z No. of bitstreams: 1 Dissert Pedro Paulo Silveira Felicíssimo.pdf: 2519035 bytes, checksum: 23d5c78d7f6eb64ebc2c2ea24e489d84 (MD5) / Approved for entry into archive by Biblioteca da Escola de Engenharia (bee@ndc.uff.br) on 2017-05-15T12:51:46Z (GMT) No. of bitstreams: 1 Dissert Pedro Paulo Silveira Felicíssimo.pdf: 2519035 bytes, checksum: 23d5c78d7f6eb64ebc2c2ea24e489d84 (MD5) / Made available in DSpace on 2017-05-15T12:51:46Z (GMT). No. of bitstreams: 1 Dissert Pedro Paulo Silveira Felicíssimo.pdf: 2519035 bytes, checksum: 23d5c78d7f6eb64ebc2c2ea24e489d84 (MD5) Previous issue date: 2016-05-05 / Este trabalho de pesquisa apresenta uma avaliação das dimensões estratégicas para proposição de um índice de valor adicional sustentável para avaliação de projetos de reciclagem de alumínio. Para este propósito, utilizou-se as metodologias do tipo qualitativa com revisão da literatura sobre os modelos, dimensões e indicadores de sustentabilidade mais utilizados por empresas, aplicando-se a pesquisa quantitativa, a partir das análises dos relatórios de sustentabilidade e das práticas reais de benchmarking do mercado de reciclagem de alumínio. O método difuso complementa a pesquisa na observação e comprovação dos comportamentos dos indicadores ambientais, econômicos, sociais e normativos, frente às adições crescentes de conteúdo reciclado no produto final. As conclusões da aplicação dos métodos qualitativo, quantitativo e difuso, sinalizam um papel preponderante da dinâmica da dimensão social do modelo para a adição de valor e de sustentabilidade aos processos da logística reversa do alumínio. O acréscimo da dimensão normativa ao modelo proposto, permite aos pesquisadores, questões e perspectivas de futuros estudos para a identificação de estratégias, padrões e parâmetros das empresas na inclusão da reciclagem ao final do ciclo de vida dos produtos. / This research presents an assessment of the strategic dimensions to propose an index of sustainable additional value for the evaluation of aluminum recycling projects. For this purpose, methods of qualitative type was used with literature review of models, dimensions and sustainability indicators most used by companies, to applying quantitative research, from the analysis of sustainability reports and the actual practices of benchmarking aluminum recycling market. The fuzzy method complements research on observation and verification of the behavior of environmental indicators, economic, social and normative, front of increasing additions of recycled content in the final product. The conclusions of the application of qualitative methods, quantitative and fuzzy, signal an important dynamic role of the social dimension of the model for adding value and sustainability to the processes of reverse logistics aluminum. The addition of the normative dimension to the proposed model, allows researchers, questions and prospects of future studies to identify strategies, standards and parameters of the companies in the inclusion of recycling at the end of life product cycle

Cette thèse est une contribution à l'étude des systèmes hybrides éoliens-photovoltaïques avec batteries sur plusieurs aspects : évaluation des sources, modélisation, simulation, optimisation du dimensionnement et enfin commande et supervision. Ainsi, dans un premier temps, une étude d'impact sur l'évaluation du potentiel en énergies renouvelables sur un site donné en prenant en compte la consommation dans un habitat résidentiel (période et méthode d'acquisition des données, techniques d'évaluation, ...) est présentée. Puis, les modèles énergétiques des différents composants du système ainsi que les aspects économiques et écologiques sont définis. L'ensemble est représenté à l'aide du logiciel Matlab/Simulink. Ensuite, une méthodologie d'optimisation du dimensionnement du système multi-sources est développée et comparée à plusieurs approches, allant d'une optimisation mono-objective à une multi-objective et évaluant le coût économique et écologique de chacune de ces solutions. Une solution « pratique » est retenue pour les composants PV, éolien et batteries du système final afin d'en évaluer la viabilité énergétique, économique et écologique. Les résultats montrent un impact environnemental faible et un coût raisonnable du point de vue économique ainsi qu'une satisfaction de la charge dans les limites tolérées par l'usager. La méthode développée de dimensionnement est comparée à un outil commercial existant. Enfin, un banc expérimental PV-éolien avec batteries est mis en oeuvre avec une nouvelle technique de supervision basée sur le contrôle des courants et l'estimation de l'état de charge des batteries. / This thesis is a contribution to the study of photovoltaic-wind-battery hybrid systems for several aspects: source evaluation, modeling and simulation, design optimization and finally control and supervision. Thus, an impact study on the evaluation of renewable energy potential at a given site taking into account consumption in residential housing (period and method of data acquisition, evaluation techniques...) is presented. In addition, all the components of the system are modeled and economic and ecological aspects are defined in order to make an overall assessment of various system configurations. All models are represented using Matlab/Simulink tool. Then, a methodology for single and multi-objective design optimization of a multi-source system is developed to minimize system Life Cycle Cost (LCC), Embodied Energy (EE) and Loss of Power Supply Probability (LPSP). A "practice solution" is thus retained and evaluated. Results show a low environmental impact and a reasonable economic cost as well as a satisfaction of the load within the limits tolerated by the user. Besides, a very convincing comparison of the developed sizing method to an existing commercial tool is presented. At the end, an experimental PV-wind-battery tested is developed in laboratory to ensure a quasi-realistic emulation of hybrid system behavior for different configurations. Accordingly, a new supervision strategy based on currents control and battery state of charge estimation is successfully validated.

The Master´s thesis is structurally divided into the theoretical and practical part. In the theoretical part, the author describes current global environmental issues and the impact of the industry on the environment. The current state of the environmental legislation in mechanical engineering, environmental management systems, and methodologies of an environmental impact assessment are described. The practical part deals with the environmental burden of the snowboard production process according to the LCA method. Life cycle inventory is performed to evaluate individual materials whose production is the most environmentally damaging. At the last stage, possible measures are proposed to reduce the environmental burden.

Hur kan livscykelanalyser bistå riskvärderingen vid val av åtgärdsmetod? I det här examensarbetet undersöktes hur resultaten från livscykelanalyser kan användas i beslutstödsverktyget SAMLA för förorenade områden för att bistå val av åtgärdsmetod vid Finspångs centraltvätt. Examensarbetet har genomförts i samarbete med Structor Miljö Öst AB. Livscykelanalyser har utförts för två olika typer av åtgärdsmetoder in situ, stimulerad anaerob reduktiv deklorering samt elektrisk konduktiv uppvärmning. Tidigare studier har visat att olika livscykelanalysmetoder ger olika resultat. Även den här studien bekräftar det. Därför bör inte resultat från olika metoder jämföras. Livscykelanalyser kompletterar SAMLA för förorenade områden väl. De procentuella förhållandena beräknades mellan åtgärdsmetodernas miljö- och klimatpåverkan. I värderingssteget i SAMLA bedöms åtgärdsalternativens påverkan i jämförelse med nollalternativet. En bedömning gjordes av respektive åtgärdsalternativ och korrigering av förhållandet mellan metoderna utfördes genom att samma procentuella förhållande som beräknats fram för miljöbelastningen respektive klimatpåverkan beräknades för värderingspoängen. Med stöd av livscykelanalyser samt riskvärdering bör efterbehandlingsmetoden stimulerad anaerob reduktiv deklorering väljas för Finspångs centraltvätt. / How can life cycle analyzes assist the risk assessment when choosing a remediation method? In this thesis, it was investigated how the results from life cycle analyzes can be used in the decision support tool SAMLA for contaminated sites to assist in the choice of remediation method at Finspång's Centraltvätt. The thesis has been carried out in collaboration with Structor Miljö Öst AB. Life cycle analyzes have been performed for two different types of in situ remediation methods, Enhanced Reductive Dechlorination and Electrical Conductive Heating. Previous studies have shown that different life cycle analysis methods lead to different results. This study also confirms this. Therefore, results from different methods should not be compared. Life cycle analyzes complement SAMLA for contaminated sites. The percentage ratios were calculated between the remediation methods' environmental and climate impact. In the valuation step in SAMLA, the impact of the remediation alternatives is assessed in comparison with the no action alternative. An assessment was made of the respectively remediation alternatives and a correction of the relationship between the methods was performed by calculating the same percentage ratio that was calculated for the valuation points of the environmental and climate impact. With the support of the life cycle analysis and the risk assessment the remediation method Enhanced Reductive Dechlorination should be chosen for Finspång's Centraltvätt.

Les chaines d’approvisionnement contemporaines sont source de problèmes environnementaux, mais aussi d’impacts pour les communautés des abords des activités de production, consommateurs, ou encore travailleurs. Pour évaluer ces impacts, l’analyse sociale du cycle de vie (ACV-S) est développée depuis quinze ans en complément de l’ACV-E, qui traite, elle, des impacts environnementaux le long du cycle de vie des produits. Cette thèse vise à répondre à certains des défis méthodologiques pour sa conception et son application, par une évaluation de produits de systèmes alimentaires alternatifs belges (SAA), et à ces deux questions: i) que devrait évaluer l’ACV-S et ii) comment intégrer les chaines de causes à effet dans l’analyse, comme en ACV-E. Sur base de trois états de l’art (des cadres d’ACV-S, des études incluant les chaines de cause à effet, et des évaluations de produits alimentaires), nous développons et mettons en œuvre des propositions qui plaident pour i) une approche participative pour définir les critères; ii) une évaluation d’impact pour comprendre les pratiques des entreprises plutôt que leur simple rapportage, à travers l’articulation des indicateurs sur la base de théories existantes, comme l’approche de Global Commodity Chain: celle-ci place la gouvernance des chaines et la répartition de la valeur ajoutée entre les acteurs comme des facteurs explicatifs potentiels des problèmes socio-économiques présents dans les chaines; iii) une approche ‘imbriquée’ de la durabilité (ou ‘nested’), qui implique la considération des aspects économiques et de gouvernance des chaines, à côté des aspects managériaux et ‘sociaux’, et leur mise en relation. Nous cherchons ainsi à contribuer à faire de l’ACV-S un outil analytique qui vise l’amélioration des principaux problèmes dans les chaines d’approvisionnement, en analysant leurs causes profondes. Nos évaluations de produits de SAA, y. c. circuits courts et commerce équitable ‘Nord-Nord’, révèlent des rémunérations trop faibles et des conditions d’emploi précaires dans les fermes, rejetant ainsi notre hypothèse d’une durabilité plus élevée de ces produits, par rapport aux chaines dominantes. Ces faibles performances résulteraient d’une reproduction des mécanismes utilisés par les chaines dominantes (rapports de force déséquilibrés, faible engagement entre les acteurs, prix inéquitables). Ceci tendrait à confirmer notre autre hypothèse selon laquelle la gouvernance des chaines et les modalités de transaction impactent les conditions socioéconomiques des travailleurs au sein de ces chaines, d’où l’intérêt de considérer ces aspects en ACV-S. Aussi, d’autres éléments semblent jouer: la règlementation du travail en vigueur, qui encouragerait les contrats précaires, ou le contexte de marché qui influencerait fortement les prix pratiqués dans les SAA, d’où l’importance de se pencher sur les chaines dominantes pour améliorer la durabilité des produits alimentaires dans leur ensemble. Notre recherche confirme l’applicabilité et la pertinence de nos propositions, qui mériteraient d’autres applications pour une validation et des développements méthodologiques supplémentaires. / Today’s supply chains entail numerous and serious issues, concerning the environment but also regarding people, including communities’ surrounding production activities, final consumers and workers. In order to assess those latter social and socio-economic impacts on people, Social life cycle assessment (S-LCA) is a tool being currently developed to complement E-LCA, which assesses potential environmental impacts along the life cycle of products and services. This PhD aims to address some of the outstanding methodological challenges faced by S-LCA, with the support of an application on products from Belgian alternative food network (AFNs). The thesis focuses on three related main questions: i) what should S-LCA assess (topics, level of assessment, i.e. company’s practices, impacts on people, other) and ii) how to include impact pathways or cause-effect chains in the analysis, as it is done in E-LCA; iii) how should the assessment be carried out, so that it goes beyond a mere reporting? On the basis of three distinct states-of-the-art (on S-LCA frameworks, studies considering impact pathways and S-LCA studies in the food sector), we put forward and apply specific methodological proposals that argue for i) the use of a participatory approach to select assessment criteria; ii) the use of an impact assessment approach that allows to understand company’s practices rather than their mere reporting, through an articulation of assessment criteria and indicators based on existing theories, including in social sciences. In this regard, the Global commodity chain approach that identify chain governance and value distribution among chain actors as potential stressors or root causes of social and socio-economic problems in supply chains, seems particularly relevant; iii) the use of a nested approach to sustainability in which also economic and governance aspects are taken into account, in addition to managerial and “social” aspects of supply chains, which are usually included. With this work we aim to contribute for S-LCA to become an analytical tool contributing the improvement of main problems in supply chains, e.g. income, employment and working conditions, by analyzing their root causes. Our assessments of products traded under various alternative chains, including short food chains and a local Fair trade chain, reveal low income and poor employment conditions on farms. This rejects our assumption of better social sustainability performances of AFN products, when compared to those of mainstream chains. Those poor performances would originate in the mechanisms used (e.g. unbalanced power relations, low commitment between VCAs, unfair prices), which are similar in mainstream chains. This would tend to confirm our assumption that chain governance and transaction modalities (i.e. business practices of chain actors) impact on socioeconomic conditions of workers in supply chains (or for the social sustainability of products), this is why we think it is of interest to consider those aspects in S-LCA. Also, other, more contextual, elements seem to come into play, such as labor regulations in force, that would encourage the use of non-standard forms of employment, and broader market context that influences AFNs quite strongly, including on prices. This is why it seems also important to work on mainstream food chains to improve overall product sustainability. Our research confirms the applicability and relevance of our methodological proposals, however further applications could be useful for further validation and methodological developments. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

The Swedish national plan for reapproval of hydropower describes that hydropower plants (HPPs) are required to be reassessed to ensure that modern environmental conditions are set for the permits. Since dams and HPPs create barriers for migrating fish and consequently disfavor biological diversity, one consequence of the national plan is that fishways are being constructed. This, in combination with an old, unfinished approval procedure from the 1960’s, resulted in the construction of three up- and downstream fishways in Mora municipality, at the HPPs in Spjutmo, Blyberg and Väsa. To fulfill requirements in regard to the fishway’s incline and safety, but at the same time minimize the need of space, the fishways have new, innovative and not yet tested design features. One of these features is the “parking garage” layout of the upstream fishway. Despite these features, the fishways take up a large amount of space and thus require large amounts of blasting, excavation and materials such as concrete and steel parts. These are climate impact influence intensive procedures and materials, but the construction has so far not been evaluated from a climate impact perspective. This, in combination with a lack of studies on the climate impact of fishways, has resulted in this project.The aim of this project was to examine the climate impact caused by the fishways in Spjutmo and Blyberg, to identify what affects the total climate impact as well as providing measures that could reduce the climate impact for future similar fishways. To provide an extensive overview of the climate impact that the fishways cause during their entire lifetime, the method life cycle analysis (LCA) was used. The construction of the fishways at Väsa HPP starts later than for Spjutmo and Blyberg, and therefore Väsa is excluded from the scope due to the lack of required information.The fishways in Spjutmo and Blyberg have the same design features, but the material consumptions differ due to their differences in head. Spjutmo’s head is 21,4 meter and Blyberg’s is 11 meter. A larger head generally results in a longer fishway which in turn results in a more material consuming construction. This resulted in the total life cycle climate impact being twice as big for Spjutmo as for Blyberg, 2 807 tonne CO2-eq respectively 1 361 tonne CO2-eq. The resource extraction is the LCA- phase that contributes the most. Concrete and its reinforcement have the biggest share of that impact, followed by mechanical parts and other steel products, road construction process in Spjutmo and the excavation process in Blyberg. Based on this result, it can be concluded that the materials and components contribute more to the fishways’ total climate impact, rather than processes. Roughly 80 % of the total climate impact origins from the upstream fishway, while the rest either stems from the downstream fishway or others. Sensitivity analyses include the climate impact caused by the fishways using some water that otherwise could have been used to generate electricity from, and the result indicates that all examined alternative energy sources would result in larger climate impact compared to if the electricity was generated by hydropower.One of the result’s uncertainties is that the fishways were under construction while this project was performed. Therefore some assumptions was made to compensate for lack of data. For example, the future electricity consumption was scaled up based off the then used electricity data. However, even if some amounts of required materials and processes changed as time went by, the changes did not make a significant difference from the bigger perspective. Sensitivity analyses that examined the climate impact of a delay in the construction also showed that the processes that are most likely to continue turned out to have a relatively small climate impact. Thus, this issue might not be as problematic as initially thought.Although the result is presented in total values, the result is also provided per a functional unit (FU) level in accordance with traditional LCA methodology. This was to facilitate a comparison for future LCAs on other fishways. The FU in this project was decided to be “One meter head for a technical, stationary, up- and downstream fishway in connection to a medium or large run-of-river hydropower plant in a cold tempered climate zone”. For future studies, LCAs on different types of fishways using the proposed FU is recommended.

This thesis investigates how a company can implement life cycle analysis (LCA) into procurement. The thesis also explores the potential synergies between the LCA and procurement. A single casestudy was utilized for this purpose. It uses LCAs using a simplified methodology, interviews, and a literature review to carry out the study. The thesis was conducted in a global telecommunications equipment company. The thesis found that the most significant benefit of implementing LCAs into procurement would be that the case company would gain the ability to know what suppliers have more environmental products. This would, in turn, enable them to premiere those suppliers. That can be done through volume purchasing agreements, where the suppliers with greener products are awarded larger purchasing volumes. It can also be done by setting emissions requirements for products, where products that do not meet the criteria are not considered for the final business award. Additionally, using LCAs over other methods or measurables allows the case company and its sourcing managers to assess the emissions a product creates using one variable, not multiple. Introducing LCAs into sourcing has its drawbacks. LCAs are inherently resource-demanding. This means that any party that conducts LCAs, either the case company or their suppliers, will have to divert resources to perform the analyses. Additionally, at this point, few sourcing managers likely know how to interpret and use the results of an LCA. Some of these issues can, to some degree, be mitigated. The case company can try to develop an LCA tool that combines the information already gathered in current systems and integrate it into the LCA. They can also try to create the LCA jointly with suppliers; through this, they can try to develop a tool that minimizes the amount of input required by suppliers while still having a high degree of detail in the analysis and results. This would likely require a significant initial investment but only the necessary resources to maintain the tool afterward. The case company could also divert resources to educate sourcing managers on LCAs, how to interpret their results, and how to push suppliers to reduce their emissions. This would again become a cost issue, and the question of how much resources the company can dedicate to educating sourcing managers will arise. Having LCAs as a tool to assess suppliers could become a new competitive advantage to the case company. Through LCAs, the case company can show its customers they are dedicated to environmental sustainability. The case company could push its industry to adopt these tools and practices through its strong market position. Further, if adopted by all the case company’s suppliers, this could influence industries beyond telecom to adopt LCAs in procurement. / Detta examensarbete undersöker om och hur ett företag kan implementera livscykelanalyser (LCA) i strategiska inköpsprocessen. Examensarbetet utforskar även de potentiella synergier mellan LCAer och strategiskt inköp. En enskild fallstudie användes för detta ändamål. Fallstudien genomfördes i ett globalt telekommunikationsutrustningsföretag. För att genomföra undersökningen användes LCAer med en förenklad metodik, intervjuer och en litteraturstudie. Examensarbetet fann att den mest betydande fördelen med att implementera LCAer i strategiskt inköp skulle var att fallföretaget skulle få möjlighet att veta vilka leverantörer som har mer miljövänliga produkter. Detta skulle i sin tur möjliggöra att premiera dessa leverantörer. Det kan göras genom volymupphandlingar, där leverantörer med gröna produkter belönas med större inköpsvolymer. Det kan också göras genom att fastställa utsläppskrav för produkter, där produkter som inte uppfyller kriterierna inte beaktas vid den slutgiltiga affärsupphandlingen. Dessutom möjliggör användningen av LCAer jämfört med andra metoder eller mätvärden att fallföretaget och dess strategiska inköpare kan bedöma utsläppen en produkt skapar med en variabel, istället för flera. Att införa LCAer i strategiskt inköp har sina nackdelar. LCAer är i grunden resurskrävande. Det innebär att vilken part som än genomför LCAer, antingen fallföretaget eller deras leverantörer, kommer behöva avsätta resurser för att utföra analyserna. Dessutom är det för närvarande troligt att få strategiska inköpare vet hur man tolkar och använder resultaten av en LCA. Vissa av dessa problem kan till viss grad mildras. Fallföretaget kan försöka utveckla ett LCA-verktyg som kombinerar informationen som redan samlats in i befintliga system och integrerar den med LCAer. De kan också försöka skapa LCAer tillsammans med leverantörer; genom detta kan de försöka utveckla ett verktyg som minimerar den mängd input som krävs av leverantörer samtidigt som de behåller en hög grad av detalj i analys och resultat. Detta skulle troligen kräva en betydande initial investering, men endast de nödvändiga resurserna för att underhålla verktyget därefter. Fallföretaget kan även avsätta resurser för att utbilda strategiska inköpare om LCA, hur man tolkar resultaten och hur man får leverantörer att minska sina utsläpp. Detta skulle återigen bli en kostnadsfråga, och frågan om hur mycket resurser företaget kan avsätta för att utbilda strategiska inköpare kommer att uppstå. Att använda LCA som ett verktyg för att bedöma leverantörer skulle kunna bli en ny konkurrensfördel för fallföretaget. Genom LCA kan fallföretaget visa sina kunder att de är dedikerade till miljömässig hållbarhet. Fallföretaget skulle kunna driva sin bransch att anta dessa verktyg och metoder genom sin starka marknadsposition. Dessutom, om samtliga av fallföretagets leverantörer antar LCA, skulle detta kunna påverka branscher utanför telekom att anta LCA i inköpsprocessen.

This study discusses the current state of climate change, which is causing rising sea levels, increasing temperatures, and threatening ecosystems due to human resource exploitation and carbon emissions. The construction industry is a significant contributor to greenhouse gas emissions, and the study aims to investigate which insulation material is best suited for a ground slab in terms of environmental impact, technical properties, and cost. The study includes a literature review and document analysis to compare the technical and environmental properties of different materials, as well as a case study to identify the most suitable material. To make the results comparable, the thickness of the different insulation layers has been chosen in such a way that the U-value becomes equivalent for all construction solutions. This has laid the foundation for the results, which demonstrates what previous research has also found: foamglass exhibits the lowest climate impact because the construction is sufficiently strong without the need for a concrete slab. However, its price is much higher compared to other construction solutions.

Hydrogen has the potential to become an important energy carrier in the future with many areas of applications, as a clean fuel for transportation, heating, power generation in places where electricity use is not fit, etc. Already today hydrogen plays a key role in numerous industries such as petroleum refineries and chemical industries. There are different production methods for hydrogen. Today, natural gas reforming is the most commonly used. With the growing importance of green production paths, hydrogen production by electrolysis is expected to grow. Two main electrolyzer technologies are used today; alkaline and polymer electrolyte membrane electrolyzer. High-temperature electrolyzers are also interesting techniques, where solid oxide is under development and molten carbonate electrolyzers is researched. In this thesis, a comparative life cycle analysis was performed on the alkaline and molten carbonate electrolyzer. Due to inaccurate inventory data for the molten carbonate electrolyzer, those results are excluded from the published thesis. The environmental performance of the alkaline electrolyzer technology was compared to that of the solid oxide and the polymer electrolyte membrane electrolyzers. The system boundaries were set as cradle to gate. Thereby, the life cycle steps included in the study are raw material extraction, electrolyzer manufacturing, hydrogen production, and transports in between these steps. The functional unit was chosen as 100 kg produced hydrogen gas. The results show that the polymer electrolyte membrane electrolyzer has the lowest environmental impact out of the compared technologies. It is also determined that the lifetime and the current density of the electrolyzers have significant impact on their environmental performance. Moreover, it is established that electricity for hydrogen production has the highest environmental impact out of the electrolyzers life cycle steps. Therefore, it is important to make sure that the electricity used for hydrogen production derives from renewable sources. / Vätgas har potential att spela en viktig roll som energibärare i framtiden med många användningsområden, såsom ett rent bränsle för transporter, uppvärmning, kraftförsörjning där elproduktion inte är lämpligt, med mera. Redan idag är vätgas ett viktigt inslag i flera industrier, där ibland raffinaderier och kemiska industrier. Det finns flera metoder för att producera vätgas, där reformering av naturgas är den största produktionsmetoden idag. I framtiden spås vätgasproduktion med elektrolys bli allt viktigare, då hållbara produktionsprocesser prioriteras allt mer. Idag används främst två elektrolysörtekniker, alkalisk och polymerelektrolyt. Utöver dessa är högtemperaturelektrolysörer också intressanta tekniker, där fastoxidelektrolysören är under utveckling och smältkarbonatelektrolysören är på forskningsstadium. I det här examensarbetet har en jämförande livscykelanalys utförts på alkalisk- och smältkarbonatelektrolysören. På grund av felaktiga indata för smältkarbonatelektrolysören har dessa resultat uteslutits från den publika rapporten. Miljöpåverkan från den alkaliska elektrolysören har sedan jämförts med miljöpåverkan från fastoxid- och polymerelektrolytelektrolysörerna. Systemgränserna sattes till vagga till grind. De livscykelsteg som inkluderats i studien är därmed råmaterialutvinning, elektrolysörtillverkning, vätgasproduktion och transporter mellan dessa steg. Den funktionella enheten valdes till 100 kg producerad vätgas.  Resultaten visar att polymerelektrolytteknologin har den lägsta miljöpåverkan utav de tekniker som jämförts. Resultaten påvisar också att livstiden och strömtätheten för de olika teknikerna har signifikant påverkan på teknikernas miljöpåverkan. Dessutom fastslås att elektriciteten för vätgasproduktion har högst miljöpåverkan utav de studerade livscykelstegen. Därför är det viktigt att elektriciteten som används för vätgasproduktionen kommer ifrån förnybara källor.