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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.
151

Sustainability Assessment of Hydrogen Production Techniques in Brazil through Multi-Criteria Analysis

Tapia, Luis Carlos Felix January 2013 (has links)
Current global demands for energy resources along with continuous global population growth have placed natural environments and societies under great stress to fulfill such a need without disrupting economic and social structures. Policy and decision-making processes hold some of the most important keys to allow safe paths for societies towards energy security and safeguard of the environment. Brazil has played a lead role within renewable energy production and use during the last decades, becoming one of the world’s leading producer of sugarcane based ethanol and adapting policies to support renewable energy generation and use. Although it is true that Brazil has historic experience with managing development of renewables and its further integration into the consumer market, there is still a lot to do to impulse new technologies that could further reduce emissions, increase economic stability and social welfare. Throughout this thesis project a sustainability assessment of hydrogen production technologies in Brazil is conducted through Multi-Criteria Analysis. After defining an initial framework for decision-making, options for hydrogen production were reviewed and selected. Options were evaluated and weighted against selected sustainability indicators that fitted the established framework within a weighting matrix. An overall score was obtained after the assessment, which ranked hydrogen production techniques based on renewable energy sources in first place. Final scoring of options was analyzed and concluded that several approaches could be taken in interpreting results and their further integration into policy making. Concluding that selection of the right approach is dependent on the time scale targeted for implementation amongst other multi-disciplinary factors, the use of MCA as an evaluation tool along with overarching sustainability indicators can aid in narrowing uncertainties and providing a clear understanding of the variables surrounding the problem at hand.
152

Environmental Assessment of Textile Material Recovery Techniques : Examining Textile Flows in Sweden / Miljöanalys av tekniker för återvinning av textilmaterial : en studie av de svenska avfallsflödena

Youhanan, Lena January 2013 (has links)
The production of textiles, focusing on cotton and polyester, carries with it major environmental concerns such as significant water and chemical use as well as the use of non-renewable resources. Measures need to be taken to decrease those environmental burdens. The present study investigates four different recovery techniques in terms of specific environmental factors. The investigated recovery methods are the Re:newcell method, polyester recycling, textile to insulation material and biogas production from the digestion of textile waste. Incineration is also included as a reference alternative. Waste flows in Sweden are estimated through a literature review of conducted waste analyses and estimations as to the amount of secondary product that can be produced from that input are duly made. Further, the environmental implications of three potential locations for a sorting facility are investigated. Converting cotton into biogas was found to be an unrealistic approach since it is economically inviable and little or no energy is actually gained when transportation costs are taken into consideration. Further studies on the benefits and costs of recycling cotton into insulation material are needed. The unavoidable transportation related to collection, sorting and recycling are not to be underestimated and could in some cases hinder future environmental improvements.  Finally, the study found that fiber material recycling is the only treatment method that has the potential to decrease the environmental burdens related to primary production although, despite the fact it requires the most water and chemicals. However, the data reliability in the current study is a matter of concern and further research in the form of standardized data collection and the use of analytical and strategic tools in further assessments is recommended. Although the recovery of textile material is crucial for decreasing the environmental burdens from primary production of textiles, the work in preventing textile waste is even more vital. In the long run, the prevention of waste is far more important as recovery processes demands their own share of resources. / Den primära produktionen av textilier för med sig enorma miljömässiga påfrestningar. Omfattande mängder kemikalier och vatten samt icke-förnybara resurser används vid tillverkningen av bomull och polyester. Det är nödvändigt att vidta åtgärder för att minska dessa negativa effekter på miljön. Denna studie syftar till att undersöka fyra olika återvinningstekniker för textilt avfall med fokus på bomull och polyester. Förbränning med energiutvinning inkluderas som ett referensfall och återvinningsteknikerna jämförs med hjälp av utvalda miljöfaktorer. De återvinningstekniker som jämförs är Re:newcells metod för återvinning av bomull (och andra cellulosa material) till viskosfiber, kemisk polyesteråtervinning, återvinning av bomull till isoleringsmaterial för byggnader samt rötning av bomullstextilier för utvinning av biogas. Avfallsströmmarna i Sverige uppskattas med hjälp av litteraturstudier av framförallt genomförda plockanalyser. Alla faktorer jämförs med avseende på 1 ton blandat textilavfall från hushåll i Sverige och hur mycket av det som kan användas som potentiell råvara i återvinningsprocesserna. Vidare undersöks även de miljömässiga effekterna som uppstår vid transport av det textila avfallet till en sorteringsanläggning och till återvinnigsanläggningar. Tre potentiella placeringar av sorteringsanläggningen undersöks: Stockholm, Vänersborg och Wolfen, Tyskland. Studien fann att endast fibermaterialåtervinning har möjlighet att motverka de miljömässiga påfrestningarna från primärproduktionen även om de också innebär den största användningen av resurser såsom vatten och kemikalier. Rötning av bomull till biogas anses vara ett orealistiskt alternativ då metoden är ekonomiskt oförsvarbar och lite eller ingen energi egentligen utvinns när man inkluderar de nödvändiga transporterna. Vidare studier behövs för att uppskatta nyttan och kostnaderna för återvinning av bomull till isoleringsmaterial. De transporter som oundvikligt behövs vid återvinning pga. insamling, sortering och återvinning bör inte underskattas och kan i vissa fall förhindra att miljönyttan ökar. Resultaten i studien bör däremot användas kritiskt då tillförlitligheten i det data som har använts i vissa fall kan ifrågasättas. Detta beror på att många antaganden och uppskattningar har gjorts pga. brist på data av sekretesskäl. Mer forskning och undersökningar rekommenderas i form av standardiserade metoder för plockanalyser av textilt avfall. Användningen av analytiska och strategiska verktyg såsom LCA och EIA/SEA rekommenderas för att ta hänsyn till alla intressenter vad gäller end-of-life för textilt avfall. Fastän återvinning är en nödvändig del i arbetet att minska på de miljömässiga påfrestningarna som primärproduktion bidrar till är det ännu viktigare att arbeta med åtgärder för att minska avfallet. Återvinning kräver sin andel resurser i from av energi, vatten och kemikalier bland annat.
153

Provision of Electric Power to CS of TGP,Using Renewable Energy Sources(on the example of Wind Turbines)

Tikhomirova, Ekaterina January 2012 (has links)
Abstract Compressor station (CS) is an essential and an integral part of gas pipeline, providing gastransportation by means of power equipment, installed at CS. It serves as a control element in thecomplex of buildings, belonging to the trunk gas pipeline. It is by compressor station operationparameters the pipeline operation mode is defined. Presence of CS allows to adjust an operation modeof the gas pipeline at gas consumption fluctuations, using the maximum of the gas pipeline storagecapacity.During the operation of compressor station there can occur some infractions of gas pumping unit(GPU) electro-receivers power supply, leading to a forced or emergency stop of at least one GPU ofCS. Wind power plants can be used as a backup power supply. Years of national and internationalexperience show that the use of wind power plants of low power (up to 5-6 kW) is almost alwayseconomically feasible in areas with average annual wind speed VAV. AN. of more than 3.5-4.0 m/s. Theuse of high-power wind power plants is justified in cases when VAV. AN. exceeds 5.5-6.0 m/s.In the master's thesis the possibility of wind power plants exploitation for uninterrupted operation ofauxiliary power plant (APP), which is a part of compressor station, is considered.In the first chapter of the thesis the condition and reliability of CS power supply system of trunk gaspipelines (TGP) is examined. Besides the issues of energy supply and gas facilities stability areconsidered; the categories of electrical receivers, as well as factors, providing the sustainability andreliability of compressor station, are defined. In the last section of this chapter the volumes of powerconsumption at compressor station and auxiliary power plant are considered.The second chapter provides a classification of wind turbines, their design and wind flowcharacteristics, as well as the methods for wind climatic characteristics determination at a giventerritory. Particular attention is paid to offshore wind turbines as the most promising wind energyinstallations.The third chapter presents environmental aspects of wind power industry: an impact on fauna, acousticnoise, vibration impact, radio waves interference, air pollution, land use, visual impact, tourism andrecreation zones.The fourth chapter represents the consideration of wind turbine exploitation, including thedevelopment of a wind energy project, the power generation base cost definition, as well as the ways toreduce the costs of power generation and prospects of development and usage of wind power industryin the Russian Federation.
154

Understanding the Recycling Behaviour of Householders in Multicultural Urban Areas:Case Study Järva, Stockholm

Miafodzyeva, Sviatlana January 2012 (has links)
Separating household waste into fractions at source is a common method of household waste collection in most European countries. In 1994 Sweden introduced producer liability legislation for packaging, which requires householders to sort, clean and recycle different types of packaging waste. The recycling behaviour of householders is complex and diverse and has been widely investigated. However, the recycling behaviour of householders living in multicultural urban areas has received less attention. Therefore, little is known about the recycling behaviour and attitudes of the ethnic minorities that comprise a sizeable proportion of many urban populations. This thesis examined recycling behaviour among multicultural householders in the urban area of Järva, north-west Stockholm, Sweden, which is home to a significant proportion of immigrants from different parts of the world. Three practical studies were conducted on the recycling behaviour of householders, with data collected through literature reviews, field screening studies for relevant cases, postal surveys and in-depth interviews with householders. A meta-analysis of studies on householder recycling behaviour published in the period 1990-2010 provided a conceptual framework for explaining recycling behaviour. It also revealed some specific features of the determining factors of recycling behaviour among householders in multicultural urban areas. For example, despite self-reported high levels of environmental concern among multicultural respondents in Järva, recycling behaviour was not determined by this factor but by attitudes towards recycling. The data also showed that the most widespread reason for participating in recycling schemes was acceptance of legal norms. The interview study indicated that providing clear, understandable and easily accessible written information in ethnic languages, supported by “word-of-mouth” information, would probably increase participation by Järva householders in recycling schemes. However, lifestyle and the ethnic origins of householders also influenced their waste generation and recycling behaviour. The methodological improvements presented here can help develop future strategies targeted at increasing the waste management behaviour of the important multicultural urban group, while also ensuring that limited resources are effectively used. / La separación de la basura doméstica en fracciones en el lugar donde se genera es uno de los métodos más comunes de recogida en la mayoría de países europeos. En 1994 se introdujo una ordenanza en Suecia sobre la responsabilidad del productor en el empaquetado. Esta ordenanza encomienda a los habitantes de las viviendas a clasificar los residuos, limpiarlos y clasificarlos en diferentes tipos. El comportamiento hacia el reciclaje de los habitantes es complejo y diverso al igual que otros comportamientos mediombientales y ha sido investigado en numerosas ocasiones. Desafortunadamente, este comportamiento cara al reciclaje en áreas urbanas multiculturales ha recibido poca atención y se conoce poco sobre la actitud hacia el reciclaje de las minorías étnicas que forman parte de la población urbana de Suecia. Esta tesis examina el comportamiento hacia el reciclaje entre los habitantes de una zona urbana multicultural del Noroeste de Estocolmo, Järva, en Suecia, en la que residen una proporción significante de inmigrantes procedentes de diferentes partes del mundo. Se han llevado a cabo tres estudios prácticos sobre el comportamiento hacia el reciclaje incluyendo datos recogidos en la bibliografía revisada, estudios de campo en algunos casos relevantes, encuestas a través de correo ordinario y entrevistas en profundidad con los habitantes. Los resultado del meta-análisis realizado sobre la actitud hacia el reciclaje publicados durante el periodo 1990-2010 indican un marco conceptual para la explicación de las formas de reciclaje. Sin embargo, los resultados de nuestro estudio revelan algunas especificidades en factores sobre el reciclaje en los habitantes de zonas multiculturales. Nuestros datos demuestran que, a pesar de un elevado nivel de compromiso medioambiental según las respuestas de los habitantes de Järva, el reciclaje no está determinado por este factor. Al contrario, las actitudes hacia el reciclaje tienen una correlación positiva y determinan los comportamientos entre los habitantes de Järva. Se ha demostrado que la principal razón para reciclar es la legalidad vigente. Los resultados de las entrevistas sugieren que una oferta clara, comprensible y de fácil acceso redactada en las diferentes lenguas de los grupos étnicos al igual que apoyada por la información transmitida “boca a boca” influiría en la participación de los habitantes de Järva. Los resultados han puesto de manifiesto que el estilo de vida y la diversidad étnica de la población influyen en la generación de residuos y el reciclaje. Esta tesis contribuye a un desarrollo metodológico que será útil para el futuro desarrollo de estrategias orientadas en la gestión de residuos al igual que asegurar un uso eficiente de los recursos. / Разделение бытовых отходов является распространенным методом сбора бытовых отходов в большенстве европейских стран.  В 1994 году Швеция ввела законодательную ответственность производителей упаковки, которая включает требование раздельной сортировки упаковочного материяла населением для последующей ее переработки. Вопрос мотивации и участия населения в раздельном сборе бытовых отходов является сложным и многосторонним и был широко исследован. Тем не менее исследованию поведения и мотивации жителей многокультурных городских районов уделялось значительно меньше внимания. Мало что известо о мотивах участия в раздельном сборе бытовых отходов в отношении этнических меньшинств, которые составляют значительную часть городских мегаполисов. Данный тезис рассматривает мотивацию и участие населения в раздельном сборе бытовых отходов в многокультурном городском районе Järva, расположенном на северо-западе Стокгольма (Швеция). Järva  явлается домом для большого числа иммигрантов из разных частей мира. Было проделанно три исследования по изучению участия населения в раздельном сборе бытовых отходов. Данные были собраны с помощью обозрений опубликованной литературы, непосредственного изучения поведения населения, анкетирования и развернутых интервью. С помощью мета-анализа литературы опубликованной в период с 1990 по 2010 годы были выделены концептуальные основы для обьяснения участия населения в раздельном сборе бытовых отходов. Также были выявлени характерные черты определяющие мотивы для участия населения из многонациональных городских районов. Не смотря на выявленный высокий уровень экологической обеспокоенности среди населения многокультурного района  Järva, участие в раздельном сборе мусора не определяется этим фактором. Тогда как персональная мотивация по отношению к  вторичной переработки отходов является движущим фактором к участию. Наиболее распространенной причиной для участия в раздельном сборе отходов стало принятие населением многокультурного района правовых норм. Интервью показали, что доступность ясной, краткой информации на национальных языках, так же как и передающаяся 'из уст в уста' информация увеличивает процент участия населения в раздельном сборе отходов. Тем не менее образ жизни и этническое происхождение влияет на состав произведенных населением отходов и их отношение к вторичной переработке. Результаты проведенных исследований направленны на усовершенствование будущих стратегий по привлечению населения многокультурных городских районнов к участию в раздельном сборе отходов, а также обеспечение того, что бы ограниченные ресурсы были использованны эффективно. / <p>QC 20120927</p>
155

Impacts of Passenger Travelling: A Scenario Study of Impacts Associated with Passenger Travelling in the Mälardalen Region

Norell Bergendahl, Annika January 2012 (has links)
This master thesis is the final assignment within my master program at the Royal Institute of Technology in Stockholm. The thesis is performed in cooperation with WSP and linked to their research project ‘On the right track”. The aim of this master thesis is to identify and estimate the impacts resulting from future passenger transports in Mälardalen region by using a scenario study methodology. The research problem this thesis is dealing with is the negative societal consequences can be expected to increase as a result of the predicted rise in passenger traffic volumes in Mälardalen. Four alternative scenarios are introduced in the thesis and compared with the projected development; Scenario 1 assumes more energy efficient vehicles, Scenario 2 expects an extended fuel substitution, Scenario 3 is based on a doubling of the public transport travelling and Scenario 4 assumes that the structurally enforced travels will be halved. From a methodological perspective, the results and discussion in the thesis indicate firstly that Mälardalen is a suitable geographical boundary in future studies related to the transport system as the region is becoming more integrated and secondly, that a wide range of impacts and modes of transport must be considered when sustainable transports are discussed. The results of the scenario analysis can be summarized as if the projected passenger transport development will decrease the energy use and the emissions, despite longer travel distances, as a result of more energy efficient vehicles. In order to reduce the negative impacts of passenger transports further, the most favorable development paths to follow are to either decrease the structurally enforced trips or to increase the public transit travelling. The reason why neither the projected development nor Scenario 1 and 2 will reduce the negative impacts is that such developments cannot reduce consequences that are not related to energy or fuel use to the same extent.
156

Carbon Footprint : A case study on the municipality of Haninge

Wu, Weiling January 2011 (has links)
AbstractCarbon Footprints, as an indicator of climate performance, help identify major GHG emission sources and potential areas of improvement. In the context of greatly expanding sub-national climate efforts, research on Carbon Footprint accounting at municipality level is timely and necessary to facilitate the establishment of local climate strategies. This study aims at exploring the methodologies for Carbon Footprint assessment at municipality level, based on the case study of Haninge municipality in Sweden. In the study, a Greenhouse Gas inventory of Haninge is developed and it is discussed how the municipality can reduce its Carbon Footprint. The Carbon Footprint of Haninge is estimated to be more than 338,225 tonnesCO2eq, and 4.5 tonnes CO2eq per capita. These numbers are twice as large as the production-based emissions, which are estimated to be 169,024 tonnes CO2eq in total, and approximately 2.3 tonnes CO2eq per capita. Among them the most important parts are emissions caused by energy use, and indirect emissions caused by local private consumption. It is worth noting that a large proportion of emissions occur outside Haninge as a result of local consumption. Intensive use of biomass for heat production and electricity from renewable sources and nuclear power have significantly reduced the climate impact of Haninge. The major barrier for Carbon Footprint accounting at municipality level is lack of local statistics. In the case of Sweden, several databases providing emission statistics are used in the research, including KRE, RUS, NIR and Environmental Account.
157

Food redistribution in Stockholm : A comparative analysis of two scenarios – with and without a food bank

Persson, Anna January 2016 (has links)
Food waste is a serious problem in today’s society. Functional food waste is going to waste treatment while people are suffering from food insecurity. Food redistribution in form of a central food bank which collects food waste at food companies and delivers it to social organizations is a measure to deal with this issue. Stockholm City Mission plans to start up a central food bank in Stockholm and it is this implementation that is of focus in this report. The purpose of this study is to compare two scenarios, with and without a food bank, and evaluate this food bank regarding the possibilities for reduced climate impacts and the economic outcomes of the involving actors (food companies, the central food bank and social organizations). The methods used are literature studies, interviews and a material flow analysis to be able to follow the flows of food through the redistribution system. The results found are that costs can be saved for the actors involved and whether the food bank will go with profit depends on the revenues that can be collected from the involved actors and external investors. Climate impacts are reduced as a result of the implementation, mainly in terms of that functional food waste avoids waste treatment and can be of use.
158

Better Low-energy Buildings : The Contribution of Environmental Rating Tools and Life-Cycle Approaches

Brown, Nils January 2014 (has links)
<p>QC 20140227</p>
159

Sustainicle TM : How to Manage Sustainability within Product Development at Saab Automobile AB

Johansson, Henrik January 2011 (has links)
Saab vehicles are recognised for being innovative, technically advanced, safe, with superior driving performance and with a characteristic design. Today the company has the broadest product portfolio ever. Saab has come to a point where there is a need for a strategic assessment of how to manage the environmental impacts and social concerns as well as to start earn profit to become a long term sustainable company. The Vehicle Development Process is the vital nerve when developing a new car and the Product Profile is the specification of requirements, it has today seven areas and sustainability could become the eight.    The aim of this thesis is to identify and establish the most relevant sustainability areas and indicators within the Vehicle Development Process at Saab Automobile AB. These sustainability areas and indicators will be put into context to develop the overall sustainability within Saab Automobile.   The research approach in this study is qualitative due to the fact that the information needed is difficult to quantify. To be able to obtain the needed information for this thesis a benchmarking study was made as well as interviews with experts besides the interviews within Saab Automobile. A disadvantage with the chosen method could be that the comparability with other studies decreases. It would probably be possible to use some of the findings within other companies.   Today Saab Automobile has no published Sustainability Report, even though a small chapter is included in the Spyker Cars Annual Report. The main findings in this study are the sustainability areas and indicators. The five identified and established sustainability areas are; Design for Sustainability, Sustainable Supply Chain, CSR, Sustainable Innovation and Sustainable Value Chain. Also are 23 potential sustainability indicators proposed for Saab. The ambition to include these areas in the Product Profile is one step towards sustainability. This is still a limited approach that seems to be doing things right (efficiency) more than doing the right things (effectiveness). Based on the sustainability areas, indicators and the benchmarking study is a new sustainability strategy proposed for Saab. / Saabs bilar är igenkända för att vara innovativa, tekniskt avancerade, säkra, med överlägsna köregenskaper och ha en karismatisk design. Idag har företaget det bredaste produktsortimentet någonsin. Saab har nu nått en punkt då det krävs ett strategiskt ställningstagande för hur företaget skall hantera miljöpåverkan, sociala konsekvenser och samtidigt vara lönsamt för att bli ett långsiktigt hållbart företag. Produktutvecklingsprocessen är livsnerven då en ny bil skall tas fram och produktprofilen är en kravspecifikation, vilken idag består av sju olika områden och där hållbarhet skulle kunna bli det åttonde.   Syftet med detta examensarbete är att identifiera och etablera de mest relevanta hållbarhetsområdena och indikatorerna inom produktutvecklingsprocessen vid Saab Automobile. Dessa hållbarhetsområden och indikatorer skall sättas in i sin kontext för att utveckla den övergripande hållbarheten inom Saab Automobile.   Forskningsansatsen i detta examensarbete är kvalitativ baserat på det faktum att den nödvändiga informationen är svår att kvantifiera. För att kunna inhämta relevant information till denna undersökning har en benchmarkingstudie genomförts likväl som intervjuer med experter och anställda vid Saab Automobile. En nackdel med den valda metoden kan vara att jämförbarheten med andra undersökningar minskar. Det är troligt att det är möjligt att använda resultaten inom andra organisationer.   Idag har Saab Automobile ingen publiserad hållbarhetsrapport, även om ett mindre kapitel är inkluderat i årsredovisningen för Spyker Cars. Huvudresultatet i denna undersökning är hållbarhetsområdena och indikatorerna. De fem identifierade och etablerade hållbarhetsområdena är; Design for Sustainability, Sustainable Supply Chain, CSR, Sustainable Innovation och Sustainable Value Chain. Samtidigt är 23 potentiella hållbarhetsindikatorer föreslagna till Saab. Ambitionen att inkludera hållbarhetsområdena i produktprofilen är ett steg mot hållbarhet, även om det är en begränsad ansats som verkar vara att göra saker rätt (eng. efficiency) mer än att göra rätt saker (eng. effectiveness). Baserat på hållbarhetsområdena, indikatorerna och benchmarkingresultaten är en ny hållbarhetsstrategi presenterad för Saab.
160

Technical and Economical Analysis of Ground Source Heat Pump Systems with BHE in Poland

Wajman, Michal January 2011 (has links)
Nowadays, Ground Source Heat Pumps (GSHPs) are more frequently acting as a main or the only device covering the building heat/cool demand. The most efficient way to extract/dissipate the low-temperature heat from/to the ground is by means of Borehole Heat Exchanger (BHE). In this Master of Science Thesis various aspects related to this technology are studied, focused on summarizing the possibilities of installing this tech-nology in Poland. Borehole drilling methods used in Poland and Sweden are analyzed and the most proper and economical ones according to Polish geological structure are proposed. Approximately for 80 % of Poland the ground should be penetrated with Mud Rotary Drilling, while for the rest 20 % DTH Air or Water driven hammer should be used. Solutions of Thermal Insulated Leg (TIL) Borehole Heat Exchanger cooperation with mechanical ventilation system are proposed and simple preliminary estimations show higher Coefficient of Performance (COP) in comparison to normal, common situation, where standard U-pipe BHE works. The possibility of using a new product (Energy Capsule - EC) in Polish conditions is surveyed, found hard to prosper at Polish market according to its high costs. Profitability of Ground Source Heat Pumps with Borehole Heat Exchanger in different geological regions of Poland is investigated. After conducted simulations it occurred that Polish lowland regions are cheaper in exploita-tion, while uplands regions are less expensive at investment level. Finally, the most ef-ficient BHE conception from those currently available at market as well as recently in-vented is suggested. Annular coaxial BHE in a form of Energy Capsule seems to be the most beneficial from all designs taken into account during performed simulations because of its low price and good thermal properties.

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