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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.
621

Obnovitelné zdroje energie a jejich dopad na regionální a municipální rozvoj v České republice / Renewable resources and their impact on regional and municipal development

Sládeček, Dušan January 2012 (has links)
This MA thesis examines the effects of wind and photovoltaic power plants on the regional development using the standard regional and statistical analysis tools. The theoretical part focuses on the macroeconomical point of view concerning the support of renewable energy sources. The consequences for Czech economy can be seen as greatly negative. The practical part includes case studies and focuses on specific municipalities. The result of the findings is that the construction of photovoltaic powe plants does not have a negative impact on the development of municipalities, in the case of smaller ones it can even be seen as an economic asset.
622

Djuren och naturens värde mot grön energi : En analys av miljökonsekvensbeskrivningar inom vindkraft för prioritering av djur ochnatur jämfört med andra intressen / Animals and nature's value against green energy : An analysis on environmental impact assessment’s in wind power on their prioritising ofanimals and nature compared to other interests

Ahlin, Nina January 2021 (has links)
Syftet med denna uppsats är att undersöka hur Miljökonsekvensbeskrivnings (MKB)dokument på vindkraft prioriterar djur och natur jämfört med andra faktorer, för dennauppsats grön energi. Grön energi i dagens samhälle värdesätts högt då det är steg närmare enhållbar framtid. MKB dokumentens syfte är att lyfta fram konsekvenser som sker till följd aven åtgärd/verksamhet. Men MKB dokument har lång väg att gå då det finns brister iprocessen.  Dessa brister beror till viss del på en avsaknad av fungerande teoretiska ramar förMKB utredningar, och dels på hur beställare och författare till MKB dokumenten påverkas avsin omgivning. I uppsatsens fall den rådande kulturen och hur samhällets syn på människansrelation till naturen och djuren är. Resultatet av uppsatsen blev: Djur och natur får ofta ståtillbaka för mänskliga intressen som värderas högre. Exempel på dessa intressen är merförnybar energi, konsekvenser för människor och deras samhälle i form av begränsadframkomst på området. En förändrad landskapsbild. Oljud, skuggtimmar och iskastning. / The purpose of this essay is to research how Environmental Impact Assessment (EIA)documents for wind power prioritises animals and nature compared to other factors, for thisessay it is green energy. Green energy in today’s society is valued high for a more sustainablefuture. EIA in Sweden has the purpose to show the consequences of an action/operation. ButEIA documents have a long way to go, because there are shortcomings in the process. Theseshortcomings are partly due to the lack of proper theoretical frameworks for EIA, and in partdue to how the authors and those who request an EIA document are affected by their society.In the essays case the dominant culture and society’s view on the relationship between manand nature and the animals there. The result of the essay is: Animals and nature often gets tostand back in the face of human interest, which is valued higher. Examples of interest are,renewable energy, consequences for humans and society in the form of limited access to thearea. A changed landscape picture (ethical value), noises, shadow hours and ice throwingfrom the rotor blades.
623

Influence of wind power feed-in and synchronous machine impedances on transient stability of heterogeneous power grids

Gries, Matthias Friedemann 03 December 2021 (has links)
Power grids constitute an essential infrastructure providing and distributing electrical energy. The grid structure is currently subject to rapid changes due to the integration of renewable energy sources. In this development one is confronted with several challenges and opportunities as, for instance, the reduction of inertial masses in the system, the strongly increasing decentralisation of generators, and the fluctuating power feed-in by generators relying on renewable energy sources. In this thesis, models are studied that describe the non-linear power-grid dynamics in the presence of fluctuating power feed-in from renewable energy sources, primarily wind turbines. Realistic features of wind-power feed-in are captured by using real data measured at a research platform located in the North Sea. This approach is applied to test systems provided by the Institute of Electrical and Electronics Engineers (IEEE), in which one conventional generator is replaced by a wind turbine. It is found that so-called dead ends and other weakly coupled network parts are particularly prone to power fluctuations and perturbations. In contrast to previous studies, the often pronounced heterogeneities of the power grid elements are taken into account when solving the non-linear power-flow and swing equations. Also reactances between locations of power generation and power feed-in are considered, which causes the link topology in the power grid to correspond to a full graph, where all nodes are effectively connected. Both the grid heterogeneities and the additional generator reactances have a decisive impact on power grid stability. Some structures considered as particularly stable in simplified models are prone to perturbations when utilising the more realistic model and vice versa. By the analysis of various quantities characterising functional grid operation, it is shown that a reliable assessment of power grid stability requires the consideration of heterogeneities and generator reactances.
624

The effects of 'going local' during the planning process for onshore wind power development

Verelzen, Wessel January 2021 (has links)
In 2015 a Written Ministerial Statement (WMS) expanded the Localism Act in England which effectively gave neighbourhoods the power to decide on onshore wind power development in their area. By doing so, the planning process for such development ‘went local’. Literature on the effects of ‘going local’ during the planning process for onshore wind power development is conflicting. On the one hand, the involvement of local communities can lead to a higher level of trust and hence a higher success rate of development processes. On the other hand, it appears that people are often reluctant to accept wind power develompent in their own area even though they are in favour of the technology in general.  This thesis explores the effects of ‘going local’, in the form of the WMS of 2015 in England, on onshore wind power development by investigating the local and neighbourhood plans, as well as the planning applications, in the administrative County of Cornwall with the help of qualitative document analysis and a thematic analysis framework provided by Braun & Clarke (2006).  The results show that currently 4 out of the 213 Parish and Town Councils in the ceremonial county of Cornwall truly comply with the WMS, which means that onshore wind power development will only be possible in these areas. The development in these and all the other neighbourhoods is limited to small-scale clusters of turbines. In addition to this, the results show that there are four over-arching aspects that play a role in the decision-making process of neighbourhoods: i) benefits for the neighbourhood, ii) negative impacts on the neighbourhood area, iii) socio-political attitude, and iv) conditions set by the neighbourhoods or local authorities.  The results show that, with the current planning policy framework in England, onshore wind power development will be limited to a significant extent in terms of size and possible locations. The conflicting literature on ‘going local’ reappears in the planning documents and a broad range of factors plays a role for all the neighbourhoods. The given weighting to the different factors is what determines a neighbourhood’s stance on onshore wind power development.
625

Toward Fully Renewable Power Systems in Regions with HighSolar Irradiation: Long-Term Planning and Operations

Alraddadi, Musfer January 2020 (has links)
No description available.
626

Tvorba inovačních zadání a jejich řešení / Theory of inventive problem solving

Lněnička, Luboš January 2012 (has links)
This thesis deals with methodology for creating innovative concepts and their solving. More precisely, TIPS methodology „Theory of inventive problem solving“. This thesis is divided into four parts. In the first part, this methodology and its five basic tools are introduced. The second part provides introduction of software Goldfire Inovator including the tools which could be useful for students working on their projects. Third part demonstrates TIPS methodology on the innovation of wind power plant supported by software Goldfire Inovator. The fourth part evaluates advantages and contributions of TIPS methodology for education and practice.
627

Critical materials for wind power: The relevance of rare earth elements for wind turbines

Brumme, Anja 29 November 2012 (has links)
On a global scale, the deployment of wind power plants is soaring. However, the availability of their construction materials could be a potential bottleneck, a problem rarely discussed in literature so far. Rare earth elements represent the most critical materials in terms of high economic importance, supply risk and environmental risk. This study therefore provides a market analysis of rare earths, ascertaining that geological scarcity is not the main problem. Instead, four kinds of market failure are identified: market power, co-production, by-production and negative externalities. Altogether, the market for rare earth metals is in a state of severe disequilibrium. Subsequently, an estimate of future rare earth demand patterns based on the wind power industry by 2050 reveals that the current level of supply is unlikely to be sufficient in the long run. To allow for a more elaborate analysis, two options of including a rare earth side condition in an integrated assessment model are finally suggested.
628

Ansätze zur Betriebsdauerverlängerung von Suzlon Windkraftanlagen

Brökel, Jan January 2016 (has links)
Hintergrund "Die ersten in Serie produzierten und kommerziell relevanten Windkraftanlagen (WKA) wurden in den frühen 1990er Jahren aufgestellt. In Deutschland, wie auch in anderen Ländern, wurden in dieser Zeit Förderprogramme wie das Stromeinspeisegesetz aufgelegt und ein zügiger Ausbau der Windenergienutzung setzte ein. So wurden zu Beginn der 1990er Jahre ca. 200 Anlagen mit je bis zu 300 kW pro Jahr installiert und Ende der 1990er Jahre waren es schon bis zu 1500 Anlagen pro Jahr mit je mehr als 1500 kW Leistung. In den 2000ern stieg die Durchschnittsleitung der jährlich installierten Anlagen auf über 2 MW auch wenn sich die Anzahl der Installationen verringerte, siehe Abbildung 1 bei Ender (Ender 2015). Insgesamt sind ca. 3000 Altanlagen entweder schon ca. 20 Jahre im Betrieb und haben damit ihre Konstruktionslebenszeit erreicht oder sind kurz davor. Wie in Abbildung 1 bei Ender (Ender 2015) deutlich zu sehen, steht damit ein rapider Anstieg der von Abriss oder Weiterbetrieb betroffenen Anlagen in den nächsten 5 Jahren bevor. ..."
629

Risikoabwägung im Rahmen einer Windkraftanlagenentwicklung

Brökel, Jan January 2012 (has links)
No description available.
630

Ekonomiska förutsättningar för vätgasproduktion som stöd till vindkraft

Nilsson, Henrik, Larsson, Christoffer January 2020 (has links)
Världen står inför utmaningen att minska sin klimatpåverkan som till en del beror på utsläpp av växthusgaser såsom koldioxid. Detta samtidigt som behovet av energi spås öka markant. Förnybara källor, företrädesvis vind- och solkraft, spås öka sin andel av den globala energiförsörjningen. Förnybar elkraftgenerering är dock inte oproblematisk då produktionen är svår att förutspå. När solen lyser eller vinden blåser sammanfaller dessutom inte alltid med när behovet av elektricitet finns vilket skapar stabilitetsproblem i elnätet. Att lagra energi för att sedan kunna återföra är ett sätt att både lösa stabilitetsproblem i elnätet och säkerställa att energi finns när den behövs. I den här studien undersöks möjligheten att, med el från vindkraft, genom elektrolys framställa vätgas som sedan lagras för att senare återföras som el via bränslecell eller säljas som råvara. Avsikten är att motverka negativa ekonomiska konsekvenser vid försäljning av intermittent vindkraft. I studien används modeller som gör simuleringar utifrån historiska data för 2019 från en vindpark. Detta för att undersöka om regleravgifter vid prognosavvikelser går att undvika eller delvis motverka samt om det går att flytta elproduktion i tid med en vätgasanläggning för att förbättra det ekonomiska utfallet för en vindkraftsproducent. Resultaten visar att detta i dagsläget inte är lönsamt utifrån de antaganden som gjorts. Detta främst för att alltför få drifttimmar uppnås i båda fallen. Studien visar att det dock kan vara lönsamt om syftet är att producera vätgas istället för att vara ett stöd för en vindkraftsproducent. / The world faces the challenge of reducing the emissions of greenhouse gases in order to mitigate climate change. At the same time, global energy demand is predicted to increase significantly. Renewable power generation like wind and solar power are believed to dominate the increase of needed power generation. These renewables power sources do not come without problems. Power fluctuations, due to their variable production causes grid stability problems and does not necessarily correspond to the demand for energy. Energy storage is a possible solution for both grid stability as well as for non-corresponding production/demand situations. This study investigates the feasability of hydrogen production by water electrolysis with electricity from a wind park. The produced hydrogen could either be sold or stored and used in a fuel cell to generate electricity at a later point in time. The aim is to mitigate negative economic consequenses from selling intermittent wind power. In the study simulations are made with historic data from 2019 from a wind park. Two models were created to investigate if imbalance costs due to forecast errors could be avoided or partially avioded and to investigate the possibility to move production of electricity in time and avoid unfavourable spot market prices. This in order to enhance the finacial results. The results from the study shows that at the present moment this is not a profitable approach with the assumptions made. The foremost reason for this is that too few system operating hours is obtained in each case. However, the results also shows that if the objective shifts from supporting wind power to producing hydrogen, the outcome could be profitable.

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