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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.
141

Att bygga hållbara småhus som privatperson : En studie om materialval, kostnad och hinder

Dahlfors, Patricia, Näsström, Sofia January 2024 (has links)
Bygg- och fastighetssektorn representerade år 2021 21,7% av Sveriges inhemska utsläpp (Boverket, 2023a). Detta visar på en stor potential i branschen att minska klimat- och miljöpåverkan som går i linje med FN:s hållbarhetsmål. Företag arbetar aktivt med att bygga mer hållbart, men privatpersoner som bygger småhus har också möjlighet att bidra till en positiv förändring. Detta projekt syftar till att jämföra olika materialval i klimatskalet i småhus ur ett hållbarhetsperspektiv. Ett av de analyserade alternativen är ett befintligt nybyggt exempelhus (småhus A) med mindre vanliga materialval, som har jämförts mot ett konventionellt sätt att bygga svenska småhus på (småhus B) som framtagits genom en enkätundersökning. Frågorna i enkätundersökningen har baserats på befintlig litteratur om vanligt förekommande material som skickats till 53 byggföretag, varav 31 företag svarat. Ett egenutvecklat förslag (småhus C) har även tagits fram med målet att förbättra materialvalen ur ett ekonomiskt och miljömässigt perspektiv.   För att kunna utvärdera miljömässig hållbarhet har en livscykelanalys genomförts där utsläpp av koldioxidekvivalenter studerats under delar av bygg- och användningsskedet. Material- och transportkostnad har även analyserats ekonomiskt med hjälp av en livscykelkostnad. För att ett förslag ska vara hållbart måste den ekonomiska och miljömässiga aspekten balanseras, som kan uppnås om lösningen är miljövänlig samtidigt som den är ekonomisk försvarbar. Det egenutvecklade förslaget är baserat på resultatet av livscykelanalysen och livscykelkostnaden från småhus A och B, samt utefter befintliga hinder som undersökts genom litteratur och ett frågeformulär som skickats ut till några aktörer som är med och påverkar byggprocessen. Två fiktiva småhusmodeller som utgår från den genomsnittliga boarean av småhus i Sverige togs fram, som resultatet av studien applicerades på för att ge en uppfattning om totalt CO2eq utsläpp och kostnad för ett småhus.   Resultatet visade att småhus B är det billigaste alternativet, men även det som genererar störst koldioxidutsläpp. För 105 000 eller 124 000 kr mer för material- och transportkostnad för de framtagna fiktiva småhusen med area 122 kvm, kan 7,1 respektive 12,1 ton koldioxidekvivalenter sparas in om materialen i småhus C används i stället. Småhus A är mer miljövänligt sett till koldioxidutsläpp än småhus B men sämre än småhus C, och ekonomiskt mer kostsamt än både småhus B och C. Det material som är den största faktorn både ekonomiskt och miljömässigt är valet av isolering i vägg och tak. Resultatet från enkätundersökningen om vanliga materialval i svenska småhus visade att det verkar finnas en branschstandard för materialval i småhus. / 21,7 % of Swedens’s domestic emissions in 2021 was represented by the building an real estate sector (Boverket, 2023a), which highlights a considerable potential to reduce emissions in line with UN:s sustainability goals. As well as companies, individuals also have the opportunity to contribute to a positive change by building more sustainable houses. This project aims to compare different materials choices in the building envelope of houses from a sustainability perspective. One of the analyzed alternatives is an existing newly built example house (house A) built with less common materials, which was compared to a conventional Swedish house (house B) based on a conducted survey. A literature study of common existing materials were the foundation for survey, which was sent to 53 construction companies were 31 companies responded. An alternative proposition (house C) was developed during the project with the goal of improving material choices from both an economic and environmental perspective.   A life cycle analysis has been conducted to evaluate environmental sustainability by studying carbon dioxide equivalent emissions during material extraction and production, transportation, and the use stage. A life cycle cost assessment has been used to analyze material and transportation cost. The economic and environmental aspects must be balanced in order for a solution to be sustainable. This can be achieved if the solution is environmentally friendly while also being economically justifiable. House C is based on the results of the life cycle analysis and life cycle cost from house A and B, as well as existing obstacles that were examined through literature and questionnaire that was sent to involved stakeholders in the building process. Two fictional house models were creates based on the average living area of small houses in Sweden. The result of the study was applied to these models to provide an estimate of the total CO2eq emissions and cost for a small house.      The obtained results showed that the cheapest option is house B, but it also generates the highest carbon dioxide equivalent emissions. For an additional cost of 105 000 sek or 124 000 sek for the fictional houses with an area of 122 square meters, 7,1 and 12,1 tons of carbon dioxide equivalent emissions could be reduced if the material propositions for house C is used instead. House A is more environmentally friendly with regards to house B, but less so than house C. On the other hand, it is more expensive then both house B and C. The biggest factor is the choice of insulation materials in walls and the roof, regarding both the economic and environmental aspect. The result of the survey on common material choices in Swedish small houses indicates that there seems to be an industry standard for material choices on these houses.
142

Livscykelanalys av det vertikala odlingssystemet Freja : En fallstudie i samarbete med Swegreen med fokus på att finna miljöpåverkans- hotspots

Brandel, Andrea, Borgström, Nora January 2024 (has links)
Livsmedelsindustrin är en bidragande faktor till klimatförändringarna, där innovativalösningar, såsom vertikal odling, kan appliceras för att främja en hållbar livsmedelsproduktion. Vertikala odlingssystem möjliggör urban inomhusodling,vertikalt i hyllplan, i kontrollerade miljöer med odlingskammare, belysningssystem samt vanligtvis jordfri odlingsmetod (t.ex. hydroponik), som är essentiella delar avsystemet. Temperatur, relativ fuktighet och artificiellt ljus regleras efter grödornas behov. Vid hydroponisk odling används odlingssubstrat såsom stenull istället för jord och växternas rötter är i konstant kontakt med det återcirkulerande vattnet i systemet, som förser växterna med näring. Tidigare livscykelanalyser av vertikala odlingssystem, om än ett begränsat antal, belyser elförbrukningen som den största bidragande faktorn till miljöpåverkan, samt att utbyte av olika material kan generera en lägre total miljöpåverkan. Examensarbetet syftar till att utföra en livscykelanalys på Swegreens vertikala odlingssystemet Freja, på ICA Maxi i Solna. Vidare syftar livscykelanalysen till att identifiera de faser och flöden som står för betydande miljöpåverkan, samt några förbättringsförslag. Det vertikala odlingssystemet antar perspektivet ‘vagga till användning’ under 30 år, exkluderande monterings- och sluthanteringsfasen. Användningsfasen innefattar sallatens livscykel från ‘vagga till grav’, exkluderande förtäringsfasen. Den funktionella enheten är 1 kg producerad ekbladssallat tillgänglig för konsumenter av klass 1. Data har inhämtats från både Swegreens digitaliserade data och från en tidigare studie utförd på Swegreens odlingssystem Saga. För bearbetning har programvaran SimaPro och databasen Ecoinvent 3.8 använts. Resultaten analyseras utifrån miljöpåverkanskategorierna ekotoxicitet (sötvatten), fossil resursanvändning, försurning, klimatförändringar, markanvändning, resursanvändning (mineraler och metaller), vattenanvändning och övergödning (sötvatten). Odlingsfasen för sallaten (innehållande elanvändning) är systemets främsta hotspot, följt av råmaterialsfasen för sallat, som orsakar störst miljöpåverkan för samtliga miljöpåverkanskategorier, förutom för resursanvändning (mineraler och metaller). Resultaten kan ej generaliseras eftersom de beror på val av funktionell enhet, systemgränser samt typ av data. Resultaten från känslighetsanalysen för energiproduktion och sluthantering tyder på att olika scenarion genererar lägst miljöpåverkan, beroende på vilka miljöpåverkanskategorier som anses mest relevanta. / The food industry is a contributing factor to climate change, where innovative solutions, such as vertical farming, can be applied to promote sustainable food production. Vertical farming systems enable urban indoor farming, vertically on shelves, in controlled environments with cultivation chambers, lighting systems and usually soil-free cultivation methods (e.g. hydroponics), that are essential parts of the system. Temperature, relative humidity and artificial light are regulated to satisfy the crops needs. Hydroponic cultivation utilizes growing mediums such as rock wool instead of soil and the roots of the plants are in constant contact with the recirculating water in the system, which provides the plants with nutrients. Previous life cycle assessments of vertical farming systems, although limited in numbers,highlight the electricity consumption as the largest contributing factor to the environmental impact, as well as replacing different materials for a lower environmental impact. This study aims to assess the environmental impacts and hot spots, through the use of life cycle assessment, on Swegreen's vertical farming system Freja, at ICA Maxi Solna. Furthermore the life cycle assessment aims to identify the phases and flows that accounts for significant environmental impact, as well as some suggestions for improvement. The vertical farming system applies the perspective of ‘cradle to use’for 30 years, not including the assembly or waste disposal phase. The use phase includes the life cycle of lettuce, from ‘cradle to grave’, not including the consumption phase. The functional unit is 1 kg of produced oak leaf lettuce, class 1,available to consumers. Data has been obtained from both Swegreen's digitized data and from a previous study conducted on Swegreen's farming system Saga. To process the data, the software SimaPro and the Ecoinvent 3.8 database was applied. Results are analyzed with regards to the environmental impact categories ecotoxicity (freshwater), fossil resource use, acidification, climate change, land use,resource use (minerals and metals), water use and eutrophication (freshwater).Results indicate that the lettuce cultivation phase (containing electricity use) is the main hotspot of the system, followed by the raw material phase for the lettuce. Aphase that also dominates in all environmental impact categories, except for resource use (minerals and metals). Results cannot be generalized since they dependon the choice of functional unit, system boundaries and type of data. The sensitivity analysis regarding the energy production and waste disposal suggests that different alternatives cause the lowest environmental impact, depending on which environmental impact categories are considered the most important.
143

Developing Consoles for Transporting Transformers by Rail

Miiro, Theodor, Persson, Daniel January 2024 (has links)
Hitachi Energy, one of the largest transformer manufacturers in the world, has a factory based in the small town of Ludvika, Sweden. Here, all of the production is carried out, from order to delivery, and the key to reaching the rest of the world lies within the Swedish railway network. Utilizing specialized railway wagons, Hitachi Energy transports the transformers to the industrial ports for further export to the rest of the world. To ensure safe transportation, with loads exceeding 400 tons, transportation consoles made for this exact purpose are used to carry the transformer's weight and keep them in place during transportation. However, with their current solution having stayed the same for many years, they now aspire to a new solution for the transportation consoles to fulfill both the physical and human-centered demands better. In this master's thesis, in industrial design engineering, a new solution for transportation consoles is being developed. To ensure the quality of the project, a design process with four stages - a learning phase, an ideation phase, a development phase, and a delivery phase - has been used. Three research questions have been in focus during the project:  What are the needs and requirements for the new transportation console? How can we identify both user needs and product requirements for the new transportation consoles through an industrial design engineering approach? How would a completely new solution for transportation consoles be designed and used in detail?  Several industrial design methods have been utilized in these phases to gain a broad knowledge of the problem and generate ideas. A product cycle analysis was conducted based on interviews and observations to better understand the product. When the knowledge was gathered, several brainstorming methods, scamper, and virtual prototyping were used to generate several new solutions and ideas. To test and develop the concepts in detail, computer-aided engineering has been used, with computer-aided design to virtually prototype the concepts and finite element analysis to verify them. The learning phase showed the need for a more user-friendly solution and how a slimmer console profile could improve the workers' overall experience. Multiple concepts of solving these problems in different ways were found in the ideation phase. After design reviews with the stakeholders and consultation with the supervisors, a final concept, Arc, for a new transportation console was chosen to continue with into the two later stages of the process. Arc's foundation lies within a human-centered design and the people interacting with it weekly. It has several advantages compared to the previous design, with its adjustability and slim design facilitating the workload and enabling easier transportation. Analyses of its durability against external accelerations have been conducted, leaning towards a promising outcome. However, further testing and verifications are needed to ensure its durability before use.
144

Description et analyse du fonctionnement énergétique des espaces bâtis. Mises en œuvre systémique du bilan carbone associé. Application à l'Éco Ferme de Vincendo et au territoire de Mayotte / Description and analysis of energy functioning of built spaces. Systemic implementation of the associated carbon footprint. Application to the Vincendo Eco Farm and the territory of Mayotte

Nidhoimi, El-Assad 19 July 2018 (has links)
Dans un contexte où les tensions liées aux ressources énergétiques fossiles sont de plus en plus vives, concevoir une nouvelle manière d'appréhender le contexte énergétique est devenu essentiel. Les moyens de production et de consommation énergétiques habituels ont montré leur limite avec l'apparition de nouveau type de pollution pour différents secteurs. Dans ce rapport de thèse, nous nous sommes essentiellement axés sur le secteur de l'électricité en proposant un outil, d'aide à la décision, pour simuler la consommation électrique ainsi que la production électrique à partir des énergies renouvelables (EnR). La simulation de la consommation électrique permet d'avoir des informations à différents échelles d'observation en s'appuyant sur une démarche systémique et typologique, qui permet de calculer le bilan carbone associé à cette consommation ainsi que son coût annuel. Par la suite, cette consommation a été analysée à l'échelle horaire afin de pouvoir là mettre en relation avec des fichiers de production pour effectuer un pilotage au niveau de la courbe de charge. Ce pilotage a pour but de lisser les pics au niveau de la courbe de charge. Les premiers résultats analytiques obtenus à l'aide des outils développés montrent qu'il est possible de réduire l'appel au réseau électrique normal à un certain niveau en fonction des dimensionnements des systèmes de production EnR et du stockage. Ainsi que de pouvoir limité les coûts d'investissement au juste nécessaire, c'est-à-dire avoir un prix le moins cher possible, grâce à une optimisation du système EnR. / In a context where the tensions linked to fossil energy resources are increasing, design a new way of understanding the energy context has become essential. The usual means of energy production and consumption have shown their limit with the appearance of new types of pollution for different sectors. In this thesis, we mainly focused on the electricity sector by proposing a tool to simulate electricity consumption and electricity production from renewable energies (RES). Simulation of electricity consumption allows having information on different observation scales based on a systemic and typological approach, according to which the associated carbon footprint to this consumption is being calculated as well as its annual cost. Subsequently, this consumption was analyzed at the hourly scale, which is to relate it to the production files in order to control the load curve. This control aims to smooth down the peaks of the load curve. The first analytical results, obtained by using the developed tools, show that it is possible to reduce the use of the normal electrical network to a certain level according to the dimensions of the RES production systems and storage.
145

The North House as Component Based Architecture

Doesburg, Chloe 17 February 2010 (has links)
The North House is a proof-of-concept prefabricated solar powered home designed for northern climates, and intended for the research and promotion of high-performance sustainable architecture. Led by faculty at the University of Waterloo, the development and design of the project involved a broad collaboration between faculty and students at the University of Waterloo, with Ryerson University and Simon Fraser University. The North House prototype competed in the U.S. Department of Energy’s Solar Decathlon in October of 2009. This thesis identifies the North House as a component-based building. It illustrates in detail the components of which the house is composed, the sequence by which they are assembled, and the details that allow for the building’s rapid assembly and disassembly. Finally, the thesis explores the possibilities afforded by componentbased architecture including adaptability, off-site fabrication and demountability. Drawing on this, the thesis projects future ways of designing buildings sustainable to both manufacture and operate.
146

The North House as Component Based Architecture

Doesburg, Chloe 17 February 2010 (has links)
The North House is a proof-of-concept prefabricated solar powered home designed for northern climates, and intended for the research and promotion of high-performance sustainable architecture. Led by faculty at the University of Waterloo, the development and design of the project involved a broad collaboration between faculty and students at the University of Waterloo, with Ryerson University and Simon Fraser University. The North House prototype competed in the U.S. Department of Energy’s Solar Decathlon in October of 2009. This thesis identifies the North House as a component-based building. It illustrates in detail the components of which the house is composed, the sequence by which they are assembled, and the details that allow for the building’s rapid assembly and disassembly. Finally, the thesis explores the possibilities afforded by componentbased architecture including adaptability, off-site fabrication and demountability. Drawing on this, the thesis projects future ways of designing buildings sustainable to both manufacture and operate.
147

Jämförande LCA av engångssängkläder och tvättbara sängkläder i sjukvården / A comparative LCA of disposable and washable beddings used in healthcare

Strömner, Fredrik January 2014 (has links)
Inom sjukvården används – precis som överallt där människor sover – sängkläder av hygienskäl. Problem med smittspridningar av typen multiresistenta bakterier (MRSA) och spridning av andra sjukdomar har drivit företag som Cellcomb i Karlstad AB till att utveckla engångssängkläder för att förhindra detta. Engångssängkläderna är skyddade av en biofilm som ska ge ökat skydd mot bakterier och fungerar som en barriär så att inte vätska tränger igenom. Problemet är att det inte finns mycket till underlag för hur engångssängkläderna står sig mot vanliga sängkläder ur miljösynpunkt. I dagsläget använder sjukhus traditionella sängkläder till sina patienter och sedan transporteras dessa till tvätteri och tvättas. Att tvätta och torka sängkläder är energikrävande och ett alternativ till detta skulle kunna vara att använda engångssängkläder. En förenklad LCA gjordes för att ta reda på om sängkläder tillverkade av bomull och polyester eller engångssängkläder tillverkade av polypropylen alternativt viskosmaterialet Tencel är det mest miljövänliga. För att ta reda på det gjordes studiebesök och data samlades in genom en litteraturstudie och från företag. Resultaten visade att i ett grundfall med Centralsjukhuset i Karlstad var energianvändningen för de tvättbara sängkläderna lägre än Tencel och försumbart lägre än polypropylen. Flera fall med känslighetsanalyser gjordes för att undersöka hur indata påverkade resultaten. Fallen visade att det kan variera vilket av alternativen som blir mest gynnsamt, framför allt när det gäller vilken typ av energi tvätteriet använder. Engångssängkläderna av Tencel visade sig vara bäst när det gällde andel förnybar energi följt av de tvättbara sängkläderna och sist polypropylen. Ur ett ekotoxicitets- och vattenanvändningsperspektiv blev båda engångssängkläderna mer gynnsamma än de tvättbara sängkläderna. Två slutsatser kan dras utifrån den här studien: de tre alternativen är likvärdiga energimässigt utifrån energianvändning, andel förnybar energi och de fallstudier som gjorts, men att engångssängkläderna står sig bättre när det gäller ekotoxicitet samt vattenanvändning. Den andra slutsatsen är att resultaten är fallberoende. En utökad studie skulle kunna göras med fler viktiga miljöparametrar och fler känslighetsanalyser. / In healthcare – as in any other place where people sleep – beddings are used for hygiene reasons. Problems with spreading of bacteria diseases such as multi resistant bacteria (MRSA) and various other diseases have pushed companies like Cellcomb i Karlstad AB to develop disposable beddings in order to prevent this. These disposable beddings are protected with a biofilm which serves as a barrier, preventing liquids to pass through. The problem is that there is not much information about how these beddings perform from an environmental perspective. At present, hospitals are using traditional beddings for their patients and are then transported to laundries for washing. This is an energy intensive process and as an alternative, disposable beddings could be used. A simplified LCA was used to find out if beddings made out of cotton and polyester or disposable beddings made out of polypropylene or a viscose material called Tencel was the most favourable from an environmental perspective. To achieve this, various study visits were performed along with a literature study and data collection from companies. The results showed that for a basic case performed with Centralsjukhuset i Karlstad the washable beddings used less energy than Tencel and negligibly less energy than polypropylene. Several case studies were performed in order to examine how different data could alter the results. The case studies showed that which of the alternatives became the most favourable varied depending on the case, especially regarding which kind of energy was being used in the laundry. The disposable beddings made out of Tencel proved to be the best alternative regarding the use of renewable energy, followed by the washable beddings and last polypropylene. From a perspective of eco toxicity and water use both of the disposable beddings turned out more favourable. Two conclusions could be drawn from this study: the alternatives are equally favourable regarding energy use, renewable energy use and the case studies that were performed, but the disposable beddings are more preferable concerning eco toxicity and water use. The second conclusion is that the results depend on which case is studied. An expanded study could be performed using more environmental parameters.
148

Développement d'une méthode d'aide à la décision multicritère pour la conception des bâtiments neufs et la réhabilitation des bâtiments existants à haute efficacité énergétique / Development of a multicriteria optimization method for decision support in designing or retrofitting high energy performance buildings

Romani, Zaid 12 December 2015 (has links)
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.
149

Dimensões estratégicas para proposição de um índice de valor adicional sustentável de avaliação de projetos de reciclagem de alumínio

Felicíssimo, Pedro Paulo Silveira 05 May 2016 (has links)
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
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Contribution au dimensionnement et à l'optimisation des systèmes hybrides éoliens-photovoltaïques avec batteries pour l'habitat résidentiel autonome / Contribution to the sizing and to the optimization of the wind-photovoltaic hybrid systems with batteries for the autonomous residential housing environment

Abbes, Dhaker 20 June 2012 (has links)
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.

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