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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.
11

Kommunikationsstrategien für nachhaltige Energie-Technologien

Schmidt, Adriane 03 February 2016 (has links) (PDF)
Die Dissertation beschäftigt sich mit der Kommunikation der beiden Energie-Technologien Wasserstoff und Offshore-Wind und untersucht, inwieweit konkrete Argumente in der Lage sind, deren Akzeptanz intendiert zu beeinflussen. Um die Wirkung von sowohl positiven als auch negativen Argumenten zu messen, wurde ein repräsentativ angelegtes Experiment durchgeführt. Die Auswahl der dort getesteten Argumente basiert auf zwei Basis-Studien, mit deren Hilfe Argumente identifiziert wurden, welche Akteure aus den Bereichen Wirtschaft, Politik, Forschung, Gesellschaft und Medien in ihrer Kommunikation nutzten: (1) Systematische Dokumentenanalyse von Kommunikationsmaterial und (2) Quantitative Medienanalyse von Nachrichtenmedien für 2009 und 2013. Dabei wurde das Ziel verfolgt, für jedes der fünf Akteurssysteme sowohl häufig (dominante) als auch selten verwendete Argumente (Reframes) aufzuspüren, um die Wirkung beider Argument-Typen zu untersuchen. Die Effekte von Argumenten auf die Akzeptanz wurden sowohl unmittelbar erfasst als auch nach einer Zeitspanne von 3 Wochen, was – durch ein Panel-Design umgesetzt – auch Aussagen über die Wirkungsdauer lieferte. Zudem wurde analysiert, inwieweit der Persuasionsprozess durch bestimmte Moderatoren beeinflusst wird: Emotionalisierung, Competitive Framing, Persönliche Betroffenheit von einer Technologie, Art der Informationsverarbeitung und Zeitpunkt der Urteilsbildung. Die Studie konnte für beide Energie-Technologien eine stärkere Wirkung dominanter Argumente im Vergleich zu Reframes feststellen. Reframes sollten deshalb in der Kommunikation nur dann verwendet werden, wenn das Argument bereits einen gewissen Bekanntheitsgrad erzielt hat. Emotionalisierung wirkte nur bedingt: Insbesondere positive Reframes sowie negative dominante Argumente konnten emotionalisiert die Akzeptanz stärker beeinflussen. Zudem wurde das NIMBY-Konzept relativiert: Besonders von einer Technologie persönlich Betroffene wurden von positiven Argumenten überzeugt – negative Argumente entfalteten ihre Wirkung dagegen eher bei Nicht-Betroffenen. Weiterhin ließen sich die Annahmen der klassischen Zwei-Prozess-Modelle der Informationsverarbeitung entkräften, da auch die in dieser Studie fokussierten inhaltlichen Argumente heuristisch verarbeitet wurden und Wirkung erzielten.
12

IDENTIFICATION OF FIRMS CAPABLE OF PRODUCING RENEWABLE ENERGY COMPONENTS IN THE KENTUCKY BLUGRASS REGION: A COMPARISON OF REPP STANDARDS CLASSIFICATION USAGE VERSUS SELF-IDENTIFICATION USING ONLINE SURVEYS

Scott A Abney (6412250) 15 May 2019 (has links)
<p>While the energy field has been primarily dominated by fossil fuels such as coal and oil, there is evidence that renewable energy sources are starting to gain a stronger foothold in the energy market to accommodate growth (Debbage, 2008; Intelligent, 2008; Sterzinger, 2006). This has been the result of greater social concern, as well as tax and other government incentives (Intelligent, 2008; Debbage, 2008). Due to these trends, a growing market opportunity exists for cities and states to increase their renewable energy component production (Intelligent, 2008; Regional, 2013; Debbage, 2008; IPCC, 2014). The primary purpose of this study was to survey existing manufacturers in the Bluegrass Region of Kentucky to obtain information and identify manufacturers who: were currently in the renewable energy market, interested in entering the renewable energy market, or have no interest in entering the renewable energy market. Respondents also addressed potential barriers to the growth of the renewable energy field including workforce development, government policy, and investment capital. A total of 25 companies responded to the survey. Correlation analysis was used and determined that no significant correlation existed between surveyed companies who identified themselves as suppliers of renewable energy components and those companies who were identified as possible suppliers of renewable energy components within the REPP (Renewable Energy Policy Project) standards. This study builds on previous methodology used by Debbage (2008) for North Carolina. </p>
13

CO2 savings of selling food surplus in plastic trays compared to incineration and anaerobic digestion in Sweden. : With an application at KTH Royal Institute of Technology / Koldioxidbesparingar med försäljning av matöverskott i plastfack jämfört med förbränning och anaerob degradering i Sverige

Rodopoulou, Viktoria January 2019 (has links)
Food waste has become a global environmental concern in recent years with food waste prevention being the optimal solution. In Sweden, initiatives to reduce food waste, focus on re-using methods like selling or donating food. The purpose of this study is to analyze the environmental savings, in terms of CO2 eq. savings, of re-using food compared to incineration and anaerobic digestion in Sweden. The study aims to map out the processes of the food waste management system and investigate the parameters that effect the performance of each method using Life Cycle Assessment (LCA). The research is conducted by using a case study, “Save food at KTH” which is an initiative at KTH Royal Institute of Technology in Sweden, to reduce food waste through a mobile application for sharing information on the available edible food waste around campus and options to purchase it through the app.   The results showed that re-using food waste has more CO2 savings compared to the other two energy recovery methods. Avoided emissions from food production when food waste is sold, were the most important factors that framed this result. However, the types of foods are also critical on the choice of food waste management method when the focus is on the CO2 emissions of the system. Foods with high water content or plant-based protein sources can be energy efficient in anaerobic digestion processes as well. In this case, selling food waste can be used as a complementary method. / Livsmedelsavfall har under senare år fått ett ökat intresse ur miljösynpunkt med förhindrande av livsmedelsavfall som den optimala lösningen för denna fråga. I Sverige är termiska behandlingsmetoder och biologiska processer för behandling av livsmedelsavfall de vanligaste metoderna för hantering av livsmedelsavfall. Båda metoderna producerar energi som kan användas för fjärrvärme, el och biobränsle för fordon. Å andra sidan, producerar dessa metoder utsläpp av växthusgaser (GHG) och många studier har erkänt deras miljöpåverkan och har jämfört dessa metoder för att identifiera alternativet med minst miljökostnad. Alternativet att sälja överbliven mat i plastlådor har potential att minska utsläppen av växthusgaser från livsmedelsavfallshanteringssystemet genom cirkulär ekonomi. Emellertid måste utsläppen av växthusgaser från de specifika livsmedelstypen samt effekten av plastlådors egenskaper och deras inverkan på plastlådors totala växthusgasutsläpp undersökas för att säkerställa effektiviteten av den försäljning av överbliven mat. Syftet med denna studie är att genomföra en livscykelanalys (LCA) om livsmedelsavfallshanteringsmetoder i Sverige för att identifiera metoden som har mest koldioxidbesparingar. Studiens mål är att kartlägga processerna i matavfallssystemet och undersöka de parametrar som påverkar prestandan för varje metod. Projektet innehåller en jämförande bedömning av klimatpåverkan (CF) av en värmebehandlingsmetod, förbränning med energiåtervinning, en biologisk metod som är anaerob uppslutning med biogasproduktion och en förebyggande metod som säljer överbliven mat i en plastlådor. En LCA utfördes för tre avfallshanteringsscenarier med två måltider (köttbaserad och vegan) som exempel när de behandlades som enskilda avfallsströmmar. Den största potentialen för att minska koldioxidutsläppen är att "sälja en måltid i ett 85% r-pet " scenario. Den undvikna köttproduktionen från att sälja matavfall kombinerat med den stora mängden återvunnet innehåll i plastlådor ger betydande koldioxidbesparingar och når den högsta nivån på avfallshierarkin som är förebyggande. Å andra sidan har förbränningen av en vegansk måltid med energiåtervinning den lägsta CO2-besparingen jämfört med de andra metoderna på grund av högvattenhalten i måltiden vilket gör den till en icke-effektiv energiomvandlare när den förbränns för att producera energi. Matavfallshanteringsmetoder bör därför fokusera på livsmedelsprodukterna och deras lämplighet för varje metod. Resultaten från denna jämförelse kommer att användas av en forskargrupp vid KTH Kungliga Tekniska Högskolan i Stockholm, Sverige, i SEED avdelningen. Gruppen bygger för närvarande en mobilapplikation för att dela / sälja matavfall runt KTH campus med ett samarbete från restaurangerna på campus.
14

Evaluation and Selection of Renewable Energy Technologies for Highway Maintenance Facilities

Andrews, Taylor January 2013 (has links)
No description available.
15

Advances in foundation design and assessment for strategic renewable energy

Dallyn, Paul A. January 2017 (has links)
In order to meet EU legislation on emissions, significant effort is being invested into the development of cost-effective renewable power generation technologies. The two leading technologies are solar and wind power because of their potential for the lowest levelised cost of energy and for showing a growth in installed capacity and technological development. Various research findings have suggested that significant cost savings in the capital expenditure of renewable energy projects can be made through the optimisation of their support foundations, the understanding of which has formed the main goal of the research.
16

Saggi empirici sui temi di innovazione, diffusione e adozione di technologie energetiche / Empirical Essays on Innovation, Diffusion and Adoption of Energy Technologies

VERDOLINI, ELENA 23 March 2011 (has links)
Questa tesi e’ composta da cinque articoli sui temi dell’innovazione, diffusione e adozione di tecnologie energetiche efficienti. Il primo capitolo presenta una rassegna della letteratura empirica sulle dinamiche del cambiamento tecnologico in campo ambientale. Il secondo capitolo studia le piu’ importanti determinanti del flusso di conoscenza. Il terzo capitolo identifica le maggiori determinanti di domanda e offerta dell’innovazione, con particolare attenzione al ruolo della conoscenza internazionale. I risultati presentati mostrano come gli spillover di conoscenza favoriscano ulteriori innovazioni. I capitoli quarto e quinto studiano il settore di produzione dell’energia elettrica. Il capitolo quarto presenta un database di brevetti in technologie energetiche efficienti. Il capitolo quinto studia le determinanti dell’efficienza energetica nella produzione di energia elettrica da fonti fossili, con particolare attenzione al ruolo della tecnologia. / This dissertation is a collection of essays on innovation, diffusion and adoption of energy technologies. Chapter 1 presents a state-of-the art review of empirical contributions on TC dynamics as applied to eco-innovation. Chapter 2 explores the main determinants of knowledge flows and how they favor or hinder the flow of knowledge across border. Both geographical and technological distance hinder the flow of eco-knowledge. Chapter 3 identifies the main demand and supply-side determinants of innovation, with particular attention to the role of foreign knowledge. I point to the importance of knowledge spillovers in fostering further eco-innovation, especially in countries with medium to low innovative abilities. Chapters 4 and 5 focus on TC in the electricity sector, a main contributor to GHG emissions. In Chapter 4 presents the data selection process used to identify patents in efficient fossil electricity technologies and provides a worldwide analysis of innovation trends in these technologies. Chapter 5 studies the evolution of energy efficiency in fossil-fuel based electricity production, devoting particular attention to the contribution of knowledge to production efficiency.
17

Comparative cost-benefit analysis of renewable energy resources for rural community development in Nigeria / A.A. Ogunlade

Ogunlade, Abimbola Adegoke January 2008 (has links)
Rural development by means of providing uninterruptible power supply has become a priority among developing countries. Nigeria especially has on its top agenda the mandate to provide clean and cost-effective means of energy to the rural communities, hardest hit by wave of incessant outages of electricity supply. Renewable Energy (RE), a clean form of energy that can be derived from natural sources is widely available throughout Nigeria but is not harnessed. In this dissertation a Cost-Benefit Analysis (CBA) framework is proposed for renewable energy towards rural community development in Nigeria as indicated in the 18-point recommendations of Energy Commission of Nigeria (ECN). Moreover, a cost-benefit analysis tool is formulated and developed from the CBA framework in order to analyze comparatively the costs and intangible benefits of renewable energy projects for rural application. A case study demonstrating the working methodology of the proposed framework is presented in order to establish the cost-benefit components by assessing the comparative cost-benefit analysis of RE at a rural site of Nigeria. Erinjiyan Ekiti rural area is located for CBA assessment with three RE resources (solar, wind and small hydro) selected for consideration. Through the application of Contingent Valuation Method (CVM), the respondents' willingness to pay for RE supply is obtained and RE benefits in monetary terms computed. Using three economic decision criteria namely: Net Present Value (NPV), Benefit-Cost Ratio (BCR) and Internal Rate of Return (IRR); the three RE resources are ranked according to their economic viability. The result of the analysis provides useful insight to investors and decision makers into how RE projects in rural community should be conducted. Foremost, it is revealed that all three RE options will be economically viable if implemented, though adequate caution must be taken when making a decision. Based on the CBA assessment, the Small-Hydro Power (SHP) option is ranked as the most viable option. However, this is swiftly negated if RE social impact, such as the spiritual belief of the rural dwellers, who rely on the only potential river as a medium of communication with their ancestors, are taken into consideration. Furthermore, a sensitivity assessment of the three RE options revealed that only solar photovoltaic (PV) option is marginally viable, thus turns negative upon an assumed increase in discount rate of only 17%. Herein, the proposed CBA framework provides a useful insight into an efficient method of appraising RE projects in rural communities. A CBA simulation tool is formulated and adapted from the CBA framework to enable quicker, reliable and automated means of assessing RE projects with a view to making wise investment decision. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
18

Comparative cost-benefit analysis of renewable energy resources for rural community development in Nigeria / A.A. Ogunlade

Ogunlade, Abimbola Adegoke January 2008 (has links)
Rural development by means of providing uninterruptible power supply has become a priority among developing countries. Nigeria especially has on its top agenda the mandate to provide clean and cost-effective means of energy to the rural communities, hardest hit by wave of incessant outages of electricity supply. Renewable Energy (RE), a clean form of energy that can be derived from natural sources is widely available throughout Nigeria but is not harnessed. In this dissertation a Cost-Benefit Analysis (CBA) framework is proposed for renewable energy towards rural community development in Nigeria as indicated in the 18-point recommendations of Energy Commission of Nigeria (ECN). Moreover, a cost-benefit analysis tool is formulated and developed from the CBA framework in order to analyze comparatively the costs and intangible benefits of renewable energy projects for rural application. A case study demonstrating the working methodology of the proposed framework is presented in order to establish the cost-benefit components by assessing the comparative cost-benefit analysis of RE at a rural site of Nigeria. Erinjiyan Ekiti rural area is located for CBA assessment with three RE resources (solar, wind and small hydro) selected for consideration. Through the application of Contingent Valuation Method (CVM), the respondents' willingness to pay for RE supply is obtained and RE benefits in monetary terms computed. Using three economic decision criteria namely: Net Present Value (NPV), Benefit-Cost Ratio (BCR) and Internal Rate of Return (IRR); the three RE resources are ranked according to their economic viability. The result of the analysis provides useful insight to investors and decision makers into how RE projects in rural community should be conducted. Foremost, it is revealed that all three RE options will be economically viable if implemented, though adequate caution must be taken when making a decision. Based on the CBA assessment, the Small-Hydro Power (SHP) option is ranked as the most viable option. However, this is swiftly negated if RE social impact, such as the spiritual belief of the rural dwellers, who rely on the only potential river as a medium of communication with their ancestors, are taken into consideration. Furthermore, a sensitivity assessment of the three RE options revealed that only solar photovoltaic (PV) option is marginally viable, thus turns negative upon an assumed increase in discount rate of only 17%. Herein, the proposed CBA framework provides a useful insight into an efficient method of appraising RE projects in rural communities. A CBA simulation tool is formulated and adapted from the CBA framework to enable quicker, reliable and automated means of assessing RE projects with a view to making wise investment decision. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.
19

Nonlinear thermoacoustic oscillations of a ducted laminar premixed flame

Kashinath, Karthik January 2013 (has links)
Finding limit cycles and their stability is one of the central problems of nonlinear thermoacoustics. However, a limit cycle is not the only type of self-excited oscillation in a nonlinear system. Nonlinear systems can have quasi-periodic and chaotic oscillations. This thesis examines the different types of oscillation in a numerical model of a ducted premixed flame, the bifurcations that lead to these oscillations and the influence of external forcing on these oscillations. Criteria for the existence and stability of limit cycles in single mode thermoacoustic systems are derived analytically. These criteria, along with the flame describing function, are used to find the types of bifurcation and minimum triggering amplitudes. The choice of model for the velocity perturbation field around the flame is shown to have a strong influence on the types of bifurcation in the system. Therefore, a reduced order model of the velocity perturbation field in a forced laminar premixed flame is obtained from Direct Numerical Simulation. It is shown that the model currently used in the literature precludes subcritical bifurcations and multi-stability. The self-excited thermoacoustic system is simulated in the time domain with many modes in the acoustics and analysed using methods from nonlinear dynamical systems theory. The transitions to the periodic, quasiperiodic and chaotic oscillations are via sub/supercritical Hopf, Neimark-Sacker and period-doubling bifurcations. Routes to chaos are established in this system. It is shown that the single mode system, which gives the same results as a describing function approach, fails to capture the period-$2$, period-$k$, quasi-periodic and chaotic oscillations or the bifurcations and multi-stability seen in the multi-modal case, and underpredicts the amplitude. Instantaneous flame images reveal that the wrinkles on the flame surface and pinch off of flame pockets are regular for periodic oscillations, while they are irregular and have multiple time and length scales for quasi-periodic and chaotic oscillations. Cusp formation, their destruction by flame propagation normal to itself, and pinch-off and rapid burning of pockets of reactants are shown to be responsible for generating a heat release rate that is a highly nonlinear function of the velocity perturbations. It is also shown that for a given acoustic model of the duct, many discretization modes are required to capture the rich dynamics and nonlinear feedback between heat release and acoustics seen in experiments. The influence of external harmonic forcing on self-excited periodic, quasi-periodic and chaotic oscillations are examined. The transition to lock-in, the forcing amplitude required for lock-in and the system response at lock-in are characterized. At certain frequencies, even low-amplitude forcing is sufficient to suppress period-$1$ oscillations to amplitudes that are 90$\%$ lower than that of the unforced state. Therefore, open-loop forcing can be an effective strategy for the suppression of thermoacoustic oscillations. This thesis shows that a ducted premixed flame behaves similarly to low-dimensional chaotic systems and that methods from nonlinear dynamical systems theory are superior to the describing function approach in the frequency domain and time domain analysis currently used in nonlinear thermoacoustics.
20

Kommunikationsstrategien für nachhaltige Energie-Technologien: Beeinflussung der Akzeptanz von Wasserstoff und Offshore-Wind

Schmidt, Adriane 28 January 2016 (has links)
Die Dissertation beschäftigt sich mit der Kommunikation der beiden Energie-Technologien Wasserstoff und Offshore-Wind und untersucht, inwieweit konkrete Argumente in der Lage sind, deren Akzeptanz intendiert zu beeinflussen. Um die Wirkung von sowohl positiven als auch negativen Argumenten zu messen, wurde ein repräsentativ angelegtes Experiment durchgeführt. Die Auswahl der dort getesteten Argumente basiert auf zwei Basis-Studien, mit deren Hilfe Argumente identifiziert wurden, welche Akteure aus den Bereichen Wirtschaft, Politik, Forschung, Gesellschaft und Medien in ihrer Kommunikation nutzten: (1) Systematische Dokumentenanalyse von Kommunikationsmaterial und (2) Quantitative Medienanalyse von Nachrichtenmedien für 2009 und 2013. Dabei wurde das Ziel verfolgt, für jedes der fünf Akteurssysteme sowohl häufig (dominante) als auch selten verwendete Argumente (Reframes) aufzuspüren, um die Wirkung beider Argument-Typen zu untersuchen. Die Effekte von Argumenten auf die Akzeptanz wurden sowohl unmittelbar erfasst als auch nach einer Zeitspanne von 3 Wochen, was – durch ein Panel-Design umgesetzt – auch Aussagen über die Wirkungsdauer lieferte. Zudem wurde analysiert, inwieweit der Persuasionsprozess durch bestimmte Moderatoren beeinflusst wird: Emotionalisierung, Competitive Framing, Persönliche Betroffenheit von einer Technologie, Art der Informationsverarbeitung und Zeitpunkt der Urteilsbildung. Die Studie konnte für beide Energie-Technologien eine stärkere Wirkung dominanter Argumente im Vergleich zu Reframes feststellen. Reframes sollten deshalb in der Kommunikation nur dann verwendet werden, wenn das Argument bereits einen gewissen Bekanntheitsgrad erzielt hat. Emotionalisierung wirkte nur bedingt: Insbesondere positive Reframes sowie negative dominante Argumente konnten emotionalisiert die Akzeptanz stärker beeinflussen. Zudem wurde das NIMBY-Konzept relativiert: Besonders von einer Technologie persönlich Betroffene wurden von positiven Argumenten überzeugt – negative Argumente entfalteten ihre Wirkung dagegen eher bei Nicht-Betroffenen. Weiterhin ließen sich die Annahmen der klassischen Zwei-Prozess-Modelle der Informationsverarbeitung entkräften, da auch die in dieser Studie fokussierten inhaltlichen Argumente heuristisch verarbeitet wurden und Wirkung erzielten.

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