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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.
121

Modèles simplifiés d’Analyse de Cycle de Vie : cadre méthodologique et applications aux filières de conversion d’énergie / Simplified Life Cycle Assessment models : methodological framework and applications to energy pathways

Padey, Pierryves 27 November 2013 (has links)
La transition énergétique est un enjeu majeur actuel et des années à venir. Parmi les défis qu’elle va soulever figure la limitation des impacts environnementaux de la production d’électricité. Pour cela, des outils d’aide à la décision, simples d’utilisation et suffisamment précis, considérant les aspects environnementaux et permettant d’optimiser les choix énergétiques futurs, doivent être mis en place. L’analyse environnementale d’une filière de conversion d’énergie est un sujet complexe. Elle comporte en effet deux niveaux. Le niveau « filière », caractérise le profil global d’impacts environnementaux des systèmes, et le niveau « système » caractérise leurs impacts, permettant ainsi une analyse intra-filière. Pour répondre à ce besoin de caractérisation en deux niveaux, nous proposons une méthodologie générique permettant de développer des modèles d’estimation des profils environnementaux de chacune des filières et d’estimer simplement ceux des systèmes qui la composent sans avoir à réaliser une étude détaillée. Cette méthodologie repose sur la définition d’un modèle d’Analyse de Cycle de Vie paramétré prenant en compte, par Analyse Globale de Sensibilité, un large échantillon de systèmes représentatif des configurations observées en pratique au sein des filières. Dans un second temps, des modèles simplifiés estimant les performances environnementales des systèmes sont définis, en fonction de quelques paramètres clefs identifiés comme expliquant la plus grande part de variance des impacts environnementaux de la filière. Cette méthodologie de réduction de modèle a été appliquée à la filière éolienne terrestre en Europe et à la filière photovoltaïque résidentielle en France. / The energy transition debate is a key issue for today and the coming years. One of the challenges is to limit the environmental impacts of electricity production. Decision support tools, sufficiently accurate, simple to use, accounting for environmental aspects and favoring future energetic choices, must be implemented. However, the environmental assessment of the energy pathways is complex, and it means considering a two levels characterization. The “energy pathway” is the 1st level and corresponds to its environmental distribution, to compare overall pathways. The “system pathway” is the 2nd level and compares environmental impacts of systems within each pathway. We have devised a generic methodology covering both necessary characterization levels by estimating the energy pathways environmental profiles while allowing a simple comparison of its systems environmental impacts. This methodology is based on the definition of a parameterized Life Cycle Assessment model and considers, through a Global Sensitivity Analysis, the environmental impacts of a large sample of systems representative of an energy pathway. As a second step, this methodology defines simplified models based on few key parameters identified as inducing the largest variability in the energy pathway environmental impacts. These models assess in a simple way the systems environmental impacts, avoiding any complex LCAs. This reduction methodology has been applied to the onshore wind power energy pathway in Europe and the photovoltaic energy pathway in France.
122

Evaluation des impacts environnementaux du chalutage de fond et de l'aquaculture en Tunisie : approche comparative par les Analyses de Cycle Vie (ACV) / Environmental impact assessment of demersal trawling and aquaculture in Tunisia : comparative approach using Life Cycle Assessment (LCA)

Abdou, Khaled 14 December 2017 (has links)
L'aquaculture et la pêche impactent l'environnement, les ressources et le fonctionnement des écosystèmes. L’un des enjeux en écologie est de placer ces activités anthropiques dans un cadre de développement durable. Afin de quantifier et de limiter ces impacts, différentes méthodes d’évaluation environnementale ont vu le jour. L’Analyse de Cycle de Vie (ACV) est une méthode pertinente pour évaluer le bilan environnemental d'un produit en prenant en compte l’ensemble de ses étapes de vie, "du berceau à la tombe", depuis l’extraction des matières premières et leurs transformations pour l'élaboration du produit, jusqu’à la fin de vie. Cette thèse porte sur l’adaptation de l’ACV au domaine de l'aquaculture et de la pêche en Tunisie. Son objectif est d'explorer les perspectives offertes par cette méthodologie afin de mieux caractériser le fonctionnement des systèmes de production de poissons et leur lien avec l’environnement. Cette étude a montré que les pratiques aquacoles et la production d'aliment de poisson sont les contributeurs majeurs aux impacts environnementaux, ceci est expliqué par l'utilisation de farine et d'huile de poisson dans la fabrication de l'aliment. Les résultats ont également montré que les impacts du chalutage de fond sont proportionnels à la quantité de carburant nécessaire pour la production. Ce travail a permis d'étudier et comparer les impacts environnementaux de l'activité aquacole et de la pêche au chalutage de fond en Tunisie. Les résultats de cette thèse ont un intérêt pour les gestionnaires en proposant des voies d'amélioration et des recommandations stratégiques de gestion pour améliorer les deux secteurs afin de les placer dans un contexte de développement durable. / The main goal of ecology is to place human activities within a framework of sustainable development by enhancing their economic benefits, their social attractiveness and their environmental performances. Ecosystems that support fisheries and aquaculture are subject to several alterations of significant relevance to their functioning and to their abilities to provide goods and services. Therefore, the long-term sustainability of fishing and aquaculture is a major concern from an environmental and ecological viewpoint. Both activities carry risks of negative environmental impacts because of its close relation with the immediate environment. To better understand environmental impacts and ensure the sustainability of fishing and aquaculture, it is necessary to develop an integrative sciencebased approach to impact assessment. Life Cycle Assessment (LCA) has emerged as a robust method to estimate potential environmental impacts associated with a product. It allows the assessment of environmental impacts “from cradle to grave”, taking into account all stages of a product’s life. This thesis focuses on the adaptation of LCA to demersal trawling and aquaculture in Tunisia. The goal is to explore how LCA improves the environmental evaluation of seafood production systems and how it helps to better understand their links with the environment. Results revealed that rearing practices and fish feed were the greatest contributors to the impacts studied due to the production of fish meal and oil and the low efficiency of feed use. The study also showed that impact intensity of demersal trawling was proportional to the amount of fuel consumed. LCA is a valuable tool for assessing how to improve environmental sustainability of demersal trawling and aquaculture.
123

Évaluation des performances environnementales de l'insertion d'une filière de méthanisation centralisée au sein d'un territoire / Environmental design and assessment of anaerobic digestion schemes that are consistent with the territory

Laurent, Faustine 06 March 2015 (has links)
En France, le développement rapide de la méthanisation, procédé de production d'énergie renouvelable par dégradation de résidus organiques, soulève la question de la pertinence environnementale de la filière. Cette dernière mérite d'autant plus d'être évaluée que le développement de la filière est inscrit dans les plans climatiques et énergétiques nationaux. La méthanisation centralisée s'insère d'ailleurs de manière profitable dans diverses démarches d'écologie industrielle et territoriale (EIT), au sein desquelles la multifonctionnalité du procédé constitue un atout substantiel en faveur du bouclage des flux de matière et d'énergie. Cette multifonctionnalité représente néanmoins la principale source de difficultés méthodologiques rencontrées lors de l'évaluation des performances environnementales de systèmes de méthanisation. Sa résolution, à savoir la définition de la fonction principale d'un système, passe par la contextualisation de la méthode. Pour l'analyse du cycle de vie (ACV), cette contextualisation se révèle pertinente dès la première étape de la méthodologie. Ce travail de thèse propose un cadre conceptuel visant à définir des scénarios de méthanisation contraints par leur territoire d'implantation. Pour cela, une approche systémique territoriale, impliquant les systèmes d'information géographique (SIG) et la modélisation orientée objet, a été développée. Elle résulte en un modèle spatial de l'insertion territoriale d'une filière de méthanisation centralisée, qui intègre l'ensemble de ses éléments constitutifs, réseaux ou variables. A l'issue de l'approche systémique a lieu une phase d'optimisation fonctionnelle et spatiale qui met en jeu trois séries successives d'indicateurs, permettant de définir : (i) la fonction principale que remplirait un système de méthanisation au sein du territoire étudié, (ii) les configurations possibles d'un système de méthanisation qui puissent satisfaire à cette fonction principale et (iii) les zones préférentielles d'implantation des scénarios élaborés. Cette méthodologie, conçue de manière à être transposable à tout territoire français, s'intègre aux étapes de l'ACV de définition des objectifs et d'inventaire du cycle de vie. Afin de valider l'applicabilité de la méthode développée, deux territoires contrastés ont été soumis à l'approche systémique territoriale. Ces cas d'étude ont mis en évidence les liens entre spécificités territoriales et conception de la filière. L'influence de la fonction principale retenue pour un système de méthanisation sur la réalisation et les résultats de l'ACV a par ailleurs été étudiée pour l'un de ces territoires. Les différences les plus notoires tiennent aux substitutions et montrent l'importance de développer la méthanisation en priorité lorsque le contexte local permet aux fonctions multiples de la filière de remplacer des filières existantes dont les impacts sur l'environnement sont particulièrement préjudiciables. / In France, the rapid development of anaerobic digestion (a process used to generate renewable energy by breaking down organic residues) has led to the environmental relevance of this solution being questioned. It is particularly worthwhile evaluating inasmuch as development of the sector forms part of national climate and energy plans. Centralised anaerobic digestion also fits in profitably with various industrial ecology approaches, with the multifunctionality of the process constituting a substantial asset in that it favours circular flows of materials and energy. However, this multifunctionality also represents the main source of the methodological difficulties encountered in the evaluation of the environmental performance of anaerobic digestion systems. Resolving this, i.e. defining the main function of a system, requires the environmental evaluation method to be contextualised. For life cycle assessment (LCA), this contextualisation emerges as being appropriate to the first stage of the methodology. This thesis puts forward a conceptual framework, aimed at defining anaerobic digestion scenarios that are consistent with the particularities of the territory in which they are located. To do this, a territorial systemic approach, involving geographic information systems (GIS) and object-oriented modelling, was developed. The approach has resulted in a spatial model for territorial location of a centralised anaerobic digestion solution, incorporating all its component parts, networks and variables. The systemic approach was followed by a phase of functional and spatial optimisation involving three successive sets of indicators, enabling the following to be defined: (i) the main function to be played by an anaerobic digestion system within the territory studied, (ii) the possible configurations of an anaerobic digestion system capable of fulfilling this main function and (iii) the preferential zones for locating the scenarios envisaged. This methodology, designed to be transposable to any territory within France, forms part of the first two LCA stages, i.e. definition of objectives and life cycle inventory. In order to validate the applicability of the method developed, the territorial systemic approach was applied to two different territories. These case studies highlight the links between specific territorial characteristics and the design of the local solution. The influence of the main function selected for an anaerobic digestion system on the performance and results of the LCA was also studied for one of these territories. The most noteworthy differences relate to substitution, highlighting the importance of developing anaerobic digestion as a priority when the local context makes it possible for the multiple functions of the solution to replace existing sectors with particularly harmful effects on the environment.
124

Avaliação do ciclo de vida da produção do painel de madeira MDP no Brasil / Life cycle assessment of MDP wood-based panel production in Brazil

Diogo Aparecido Lopes Silva 12 July 2012 (has links)
Neste trabalho foi realizada a Avaliação do Ciclo de Vida (ACV) da produção do painel MDP (medium density particleboard), feito de partículas de madeira e adesivo sintético, largamente empregado na indústria moveleira, sendo o painel de madeira mais produzido e consumido no mundo. O objetivo deste trabalho foi avaliar o ciclo de vida produtivo (cradle to gate) do painel MDP no Brasil. A ACV é normalizada pelas séries ISO 14040 e 14044. Empresas produtoras do MDP no país foram visitadas para a coleta de dados, e na avaliação dos impactos ambientais os resultados foram comparados pelos métodos CML (2001), EDIP (1997) e USEtox (2008). Os resultados apontaram que os principais hotspots foram o óleo BPF (baixo ponto de fluidez) utilizado na planta de energia e a resina UF (ureia formaldeído), aplicada como aglomerante na produção dos painéis. A cadeia produtiva da madeira mostrou maior destaque para as categorias de eutrofização e ecotoxicidade, respectivamente, pelo uso de fertilizantes e do herbicida glifosato no solo. Também verificou-se que na produção de 1 m³ de painel MDP há um crédito de carbono médio de 969 kg de \'CO IND.2\'-eq. Perante os resultados, foram analisados diversos cenários com sugestões de melhorias ambientais, sendo propostas alterações quanto ao consumo das matérias primas: óleo BPF, resina UF e madeira. Para o óleo BPF, o cenário ambientalmente mais adequado foi a sua substituição total pelo uso de somente resíduos de madeira. Sobre a resina UF, verificou-se que os principais impactos estão relacionados às cadeias produtivas do metanol e da ureia, sendo assim sugerida a otimização no consumo destes recursos. Também, a resina UF foi comparada com a resina MUF (melamina ureia formaldeído), e percebeu-se que os impactos ambientais da segunda foram superiores. Porém, mais cenários analisando o emprego de resinas alternativas são requisitados, tendo em vista a busca por resinas análogas à UF, mas com menores impactos potenciais. E sobre a madeira, foi analisada sua substituição pela adição de resíduos de madeira na produção do MDP, tendo sido constatado que quanto maior a quantidade de resíduos adicionados, menores seriam os impactos ambientais. Todavia, os benefícios ambientais verificados com o uso dos resíduos dependem de variáveis, como: dos aspectos ambientais do ciclo de vida dos resíduos, da quantidade de resíduos aplicada na produção dos painéis, do critério de alocação adotado na ACV, e da distância no percurso de transporte dos resíduos até a fábrica de painéis. Portanto, deve-se analisar caso a caso para afirmar sobre a viabilidade ambiental no emprego de resíduos na produção de painéis de madeira. / In this project was carried out a study of Life Cycle Assessment (LCA) of the MDP (medium density particleboard) production, made of wood particles and synthetic adhesive, widely used in furniture industry, being the most produced and consumed wood-based panel in the world. This study aimed to assess the productive life cycle (cradle to gate) of the MDP in Brazil. LCA technique is standardized by ISO 14040 and 14044 documents. The data collection phase in this study occurred realizing technical visits on the Brazilian MDP producers and for the environmental impact assessment, the results were compared considering the following methods: CML (2001), EDIP (1997) and USEtox (2008). The results showed that the main hotspots were the heavy fuel oil used on power plants and UF (urea formaldehyde) resin applied as binder to produce the panels. The wood consumption showed to be more relevant to eutrophication and ecotoxicity impact categories, respectively, by the use of fertilizers and the glyphosate herbicide in the soil. It was also observed that the production of 1m³ of MDP generates an average carbon credit of 969 kg of \'CO IND.2\'-eq. Given the results, several scenarios were analyzed including environmental suggestions of improvements, being proposed changes to the consumption of the raw materials: heavy fuel oil, UF resin and wood. The replacement of heavy fuel oil for wooden residue was the most suitable alternative, because the environmental impacts results were considerably reduced. For the UF resin, it was found that the main impacts are related to the production (cradle to gate) of methanol and urea, thus, we suggested optimizing the consumption of these resources. Also, UF resin was compared with the MUF (melamine urea formaldehyde) resin, and the second one showed more impacts than the first. However, more scenarios analyzing the use of alternatives resins are required, in order to find others options of similar resins to UF, but with lower potential impacts. Considering the wood consumption, it was examined its replacement by wooden residue like raw material to produce the MDP. The results pointed out the addition of residues can promote lower environmental impacts. On the other hand, the environmental benefits related depend of variables such as: the environmental aspects of the life cycle of waste generation, the quantity of waste applied to produce the panels, the allocation criteria adopted to the LCA study, and the distance to transport the waste to the panel industry. Therefore, one must examine each case to assert about the environmental sustainability in the use of waste to produce wood panels.
125

Einsatz biogener Kraftstoffe zur Senkung der Emissionen von stationären Verbrennungsmotoren

Rau, Florian 26 August 2021 (has links)
Diese Arbeit beschäftigt sich mit dem Einsatz biogener Ersatzbrennstoffe bei der motorischen Verbrennung. Zum einen wurden die laminaren Brenngeschwindigkeiten von Ethanol und iso-Butanol sowie Gemischen mit iso-Oktan bestimmt. Es konnten Messwerte für die Validierung von numerischen Mechanismen sowie Parameter für die Abbildung der Temperatur- und Druckabhängigkeit der Brenngeschwindigkeit bestimmt werden. Der Vergleich der Messverfahren zeigt eine gute Übereinstimmung. Zum anderen wurden die Auswirkungen der Beimischung von Wasserstoff auf die Abgaszusammensetzung und den Wirkungsgrad an einem Verbrennungsmotor ermittelt. Die Erhöhung des Wasserstoffanteils führt zur Erhöhung des Wirkungsgrades. Die Abgasbestanteile Kohlenstoffmonoxid, Formaldehyd und Methan werden reduziert, während Stickoxide zunehmen. Mit den begleitenden Simulationen kann gezeigt werden, dass höhere Wasserstoffanteile die Oxidation durch einen erhöhten Anteil an OH-Radikalen begünstigen. Der Grund für das verstärkte Auftreten von Stickstoffmonoxid liegt in der Verlängerung der Verweilzeit der verbrannten Gase in der Oxidationszone.
126

Quantifying the Environmental Performance of a Stream Habitat Improvement Project

Morse, Cody 01 August 2018 (has links)
River restoration projects are being installed worldwide to rehabilitate degraded river habitat. Many of these projects focus on stream habitat improvement (SHI), and an estimated 60%of the 37,000 projects listed in the National River Restoration Science Synthesis Program focus on SHI for salmon and trout species. These projects frequently lack a sufficient monitoring program or account for the environmental costs associated with SHI. The present study used life cycle assessment (LCA) techniques and topographic effectiveness monitoring to quantify environmental costs on the basis of geomorphic change. This methodology was a novel approach to assessing the cost-benefit relationship of SHI. To test this methodology, two phases of the Lower Scotts Creek Floodplain and Habitat Enhancement Project (LSCR) were used as a case study. The LSCR was a SHI project installed along the northern coast of Santa Cruz County, California, USA. A limited scope LCA was used to quantify the life cycle impacts of raw material production, materials transportation, and on-site construction. Once these baseline results were produced, a topographic monitoring program was used to quantify the topographic diversity index (TDI) in pre- and post-project conditions. The TDI percent change was used to scale the baseline LCA results, which quantified the environmental impacts based on geomorphic change. Phase II outperformed phase I. Phase I had greater cumulative environmental impacts and experienced a 7.7 % TDI increase from pre- to post-project conditions. Phase II had 43% less cumulative environmental impacts and experienced a 7.9% TDI increase from pre- to post-project conditions. The impacts in phase I were greater because of the amount of material excavated to create off-channel features, which were a key feature of the LSCR. A scenario analysis also was conducted within the LCA component of this study. The scenario analysis suggests that life cycle impacts could be reduced by 30%-65% by using the accelerated recruitment method in place of importing materials to build large wood complexes. The results of this study suggest that managers may improve the environmental performance of SHI projects by: (1) using the accelerated recruitment method to introduce larger key pieces to the channel, reducing the need to import materials; (2) using nursery grown plants as opposed to excavating plants for revegetation; (3) minimizing fuel combustion in heavy equipment and haul trucks by ensuring clear access to the channel and streambank, using small engine equipment to clear access corridors during site preparation, running more fuel-efficient machinery or bio-fuel powered machinery, and by attempting to minimize haul distances by sourcing materials locally; and (4) utilizing a “franken-log” design (a ballasted LWC configuration with a rootwad fastened to the downstream end of a log) in LWCs which led to favorable TDI change. This study concluded that LCA could be a valuable tool for monitoring SHI and river restoration projects and that further research of the TDI analysis is justified.
127

Life cycle assessment of DHA produced by microalgae using food waste : Assessing global warming, fossil energy use and effects on biodiversity

Bartek, Louise January 2020 (has links)
Biodiversity is a key component for life on Earth since it contributes to clean water, fresh air and food security. Today, fatty fish farmed in aquaculture is the main Omega 3 source consumed by humans, including the essential fatty acid docosahexaenoic acid (DHA). DHA origin from plants and accumulate in fish via the marine food web. Therefore, DHA in the form of fish oil is often added to fish feed used in aquaculture. This process is dependent on fossil energy and marine raw materials, which infer increased global warming, damage to ecosystem and ultimately loss of biodiversity. In order to reduce the environmental impact, the essential fatty acid could instead be derived from the marine primary producer of DHA: microalgae. In this thesis, a life cycle approach was used to assess global warming, use of fossil fuels and Ecosystem damage when DHA is produced by the microalgae Crypthecodinium Cohnii. The environmental impact was modelled using SimaPro 9 and assessed with CML-IA and ReCiPe Endpoint. In this model, volatile fatty acids derived from dark fermentation of food waste was used as feedstock to the algae. The studied systems consisted of two parallel scenarios, one conventional food waste-to-biogas with DHA from fish oil and one conceptual food waste-to-DHA with DHA from algae oil. The aim was to evaluate the future potential of DHA produced from algae, by assessing and comparing environmental impact to DHA produced from Peruvian anchovy. For every ton DHA produced by microalgae the assessed impact was -1.9E+02 tonCO2e, -1.9 TJ and 9.7E-04 species.yr. DHA produced by microalgae using VFA from food waste was shown to mitigate global warming and reduce use of fossil fuels. The most important conclusion show that DHA from algae infer 37% lower biodiversity loss in comparison to DHA from Peruvian anchovy. Thus, DHA from microalgae could reduce dependency on marine raw material and decrease biodiversity loss. / Biodiversitet är en nyckelkomponent för liv på jorden eftersom det bidrar till rent vatten, frisk luft och säker livsmedelsproduktion. Idag är fet fisk odlad i vattenbruk den viktigaste källan till Omega 3 som konsumeras av människor, inklusive den essentiella fettsyran dokosahexaensyra (DHA). Då DHA härstammar från växter och ackumuleras i fisk via den marina näringskedjan, tillsätts DHA ofta till fiskfoder i form av fiskolja. Denna process är beroende av fossil energi och marina råmaterial, som leder till ökad global uppvärmning, skadar naturliga ekosystem och orsakar förlust av biologisk mångfald. För att minska miljöpåverkan skulle den essentiella fettsyran istället kunna produceras från den marina primärproducenten av DHA: mikroalger. I detta examensarbete användes livscykelanalys för att utvärdera miljöpåverkan med avseende på global uppvärmning, användning av fossila bränslen och påverkan på biodiversitet, då DHA produceras av mikroalgen Crypthecodinium Cohnii. Flyktiga fettsyror, VFA, som bildas vid mörk fermentering av matavfall användes som råmaterial till algerna. De studerade systemen bestod av två parallella scenarier, en konventionell matavfall-till-biogas med DHA från fiskolja och en konceptuell matavfall-till-DHA med DHA från algolja. Systemet modellerades i SimaPro 9 och miljöpåverkan beräknades med CML-IA och ReCiPe Endpoint. Syftet var att utvärdera DHA som produceras från alger genom att beräkna miljöpåverkan och jämföra med DHA producerad från peruansk ansjovis. För varje ton DHA producerat av mikroalger var påverkan -1.9E+02 tonCO2e, -1.9 TJ och 9.7E-04 arter per år. DHA producerad av mikroalger där VFA från matavfall använts som näring, visade sig minska den globala uppvärmningen, reducera användningen av fossila bränslen och innebar 37% lägre förlust av biologisk mångfald jämfört med DHA producerad från peruansk ansjovis. Denna studie visade därmed att DHA från mikroalger kunde minska beroendet av marina råmaterial och minska förlusten av biologisk mångfald.
128

Den blomstertid nu kommer? : En studie av frilandsodlade svenska snittblommor - utmaningar och möjligheter utifrån ett hållbarhets- och livscykelperspektiv

Johansson, Marika, Zeilon, Kajsa January 2022 (has links)
Cut flowers are products that have become a symbol of joy, sorrow and wealth. However, consumption contributes to various environmental problems, such as greenhouse gas emissions and leakage of nutrients and pesticides. This study aims to investigate the environmental impact of outdoor-grown cut flowers from a sustainability perspective in Sweden. The questions answered are which aspects of the cut flower lifecycle have the greatest environmental impact, what the cut flower growers think of the cut flower industry and its sustainability and how their work can become more sustainable. The study was conducted through semi-structured interviews with eight businesses that grow field-grown cut flowers and a literature review focusing on the environmental impact of cut flowers from a life cycle perspective. The results from the literature review show that the main environmental and climate aspects from a life cycle perspective are transport, heating through fossil fuels and the use of fertilizers and chemical pesticides. The results from the interviews show that challenges with the cut flower industry are origins of seeds, lack of knowledge and behavior and consumption patterns. Opportunities consist of growing demand, good quality and being able to offer a more sustainable product. Swedish field-grown cut flowers can be considered a sustainable alternative to imported ones due to shorter transport and the difference in the use of nutrients and chemicals. Although, more transparency, knowledge and collaboration will be needed in the industry for long-term sustainable development. Measures that can be implemented to promote the production and consumption of Swedish sustainable cut flowers are political incentives and possibly a certification or labeling.
129

Analyzing the environmental sustainability of an urban vertical hydroponic system / Utvärdering av den miljömässiga hållbarheten av en urban vertikal hydroponisk odling

Barge, Unni January 2020 (has links)
Food systems are considered one of the most important anthropogenic activities contributing to climate change. On the other hand, climate change influences the conditions for growth with more frequent droughts and heatwaves. This contradiction poses a significant challenge to future food systems, which need not only become more sustainable, but also increase its production to feed a growing population, as stated in both the United Nations Sustainable Development Goals, and the Swedish action plan on food. This has given rise to alternative ways of producing food, such as urban farming and, in particular vertical hydroponic farming, where food is grown indoors in a controlled environment with artificial lighting and with a minimum use of water and without pesticides. In this study, a vertical hydroponic farm located in Stockholm, Sweden, is examined using life cycle assessment in terms of environmental sustainability. The farm, located in a basement space, works together with the building in a symbiotic network, where the farm provides the building with excess heat from the lighting, and in turn obtains carbon dioxide from an office floor. The findings from the study show that electricity is a major contributor to the environmental performance of the farm, along with the infrastructure employed. The impacts of water use in the farm, is very low, along with the impacts associated with the delivery of the crops; illustrating the advantages of producing food locally. By substituting the synthetic fertilizers employed to biofertilizers, and by substituting the plastic bag material to renewable material, reductions in greenhouse gases are possible. The symbiotic development between the farm and the building is shown very beneficial to the farm, highlighting the importance of synergies between actors in urban areas. / Livsmedelsindustrin anses vara en av de största antropogena drivkrafterna bakom klimatförändringarna. Å andra sidan så förändrar klimatförändringar i sig förutsättningarna för hållbar odling, med mer frekventa torrperioder, extrem värme och extrem nederbörd. Denna konträra situation ställer stora krav på framtidens livsmedelsindustri, som dessutom måste producera mer mat för att mätta en ökande befolkning; ett åtagande som står angivet både i FN:s globala mål och i den svenska Livsmedelsstrategin. Många forskare menar att dagens livsmedelsindustri inte kommer klara denna omställning, och att alternativa metoder för att producera mat behövs. Urban odling har föreslagits som en del av lösningen, och i synnerhet vertikal hydroponisk odling där grödor växer inomhus i en kontrollerad miljö med artificiell belysning, låg vattenanvändning och utan bekämpningsmedel. Den här studien undersökte en vertikal hydroponisk odling i Stockholm, och bedömde dess miljömässiga hållbarhet med hjälp av en livscykelanalys. Odlingen, som sker i en källarlokal, samarbetar med den omslutande byggnaden i en urban symbios, där odlingen förser byggnaden med spillvärme från belysningen, och får i sin tur koldioxid från en kontorslokal. Enligt resultat från studien bidrar elektriciteten till den största miljöpåverkan, men även infrastruktur har stor påverkan. Vattenanvändningen i odlingen är däremot väldigt låg, och miljöpåverkan från leveransen av varorna är mycket låg, vilket belyser fördelarna med att odla mat lokalt. Odlingen kan bland annat minska sin miljöpåverkan genom att byta ut det nuvarande konstgödslet till biogödsel och genom att byta ut plastpåsarnas material till förnybar plast. Symbiosen mellan odlingen och byggnaden visade sig vara väldigt gynnsam, vilket vidare belyser vikten av samspel mellan olika aktörer i den urbana miljön.
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Life Cycle Assessment of a Road Ferry / Livscykelanalys av en Vägfärja

Ringström, Anna January 2019 (has links)
On a national level, the Swedish Transport Administration (STA) constitute the responsibleauthority for national long-term infrastructure planning in Sweden and therefore has animportant role for limit the environmental load from domestic transport. STA Road Ferries isresponsible actor within STA, for national infrastructure planning connected to public marinetransport and has formulated the goal of net zero GHG emissions by year 2045 for the ferryfleet. Today, yearly operation causes around 38,400 tons CO2-equivalents. Emissions fromconstruction, maintenance and deconstruction of road ferries are yet unknown. In order to reachclimate neutrality, identification of emissions from a life cycle perspective is needed. This study analyses environmental performance of a standard road ferry from an LCAperspective to be used as a baseline in future work towards climate neutrality. The LCA wasconducted in SimaPro 8.4.0 and evaluated thorough EPD (2013) methodology according to theEN 15804 standardisation. The report gives initial baseline values for the road ferry Neptunus and identifies daily operationas major hotspot in terms of total environmental impact from analysed impact categories, butalso construction phase is of importance to consider. The study further concludes that based onlong term goal and vision as STA Road Ferries has formulated them to today, a combination ofchange in construction in terms of material choices and design, together with changed fuelalternative is considered necessary in order to reach Vision 45. Future studies are recommended on this subject to reach the long term goal and vision. Forexample, studies that complement the developed model with more project specific process dataand include more components, and comparative LCA’s between different fuel alternatives. / Trafikverket är den aktör och myndighet som ansvarar för den långsiktiga, nationellainfrastrukturplaneringen i Sverige och som därför har en viktig roll i begränsandet avmiljöpåverkan från landets transportsektor. Färjerederiet är ansvarig aktör inom Trafikverketför nationell infrastrukturplanering och drift kopplat till den statliga inrikessjöfarten i form avfärjedrift. Färjerederiet har idag formulerat det långsiktiga målet att nå nollnetto utsläpp förfärjeflottan till år 2045. Idag orsakar färjedriften 38,400 ton CO2 ekvivalenter årligen vilket dåenbart är utsläpp kopplat till driften. Emissioner från konstruktion, underhåll ochdekonstruktion är dock fortfarande okänt. För att nå total klimatneutralitet behövs såledesidentifiering av emissioner ur ett livscykelperspektiv. Den här studien analyserar miljöprestandan av en standardfärja från Färjerederiets färjeflotta urett livscykelperspektiv med syfte att använda detta som utgångsläge i framtida arbete motklimatneutralitet. Livscykelanalysen genomfördes i SimaPro 8.4.0 och metoden EPD (2013)användes för utvärdering av potentiell miljöbelastning enligt EN 15804 standardiseringen. Resultaten från denna rapport är en utgångspunkt för vidare specialisering, och är baserat pådata från vägfärjan Neptunus. Studien identifierade den dagliga driften som en betydandehotspot för den totala miljöpåverkan utifrån de analyserade påverkanskategorierna, men ävenatt konstruktionen är en viktig del av livscykel att ta hänsyn till. Studien visar vidare att ettkombination av en förändrad konstruktion samt val av bränsle är nödvändigt för att nå delångsiktigt uppsatta målen som finns inom Färjerederiet i form av Vision 45. Framtida studier inom detta område är rekommenderat för att nå de långsiktigt uppsatta målen.Till exempel kan vidare studier göras för att komplettera den upprättade modellen med merprojektspecifik processdata och inkludera fler komponenter, samt utföra jämförandelivscykelanalyser mellan olika bränslealternativ.

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