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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.
181

Vägar och markanspråk inom vindkraftsparker i Västerbottens län : Hur verkliga mått förhåller sig till vad som uppges i miljökonsekvensbeskrivningar / Roads and land claims within wind farms in the County of Västerbotten : Real dimensions and what is stated in the Environmental Impact Assessment

Rönnqvist, Marie January 2011 (has links)
The purpose of this study was to increase the level of knowledge in the field of Environmental Impact Assessment (EIA) for wind power. The study includes six wind power farms in the County of Västerbotten in northern Sweden. The main questions were: What are the real dimensions of roadways and land claims for both roads and wind power turbines? How do those dimensions correlate with the dimensions stated in the EIA? Are there any differences in values of the dimensions between the wind power farms that are included in this study? The width of the roadways and the land claims for both roads and wind turbines in wind power farms were examined on site. The results from the examinations were compared with the dimensions available in the EIA for each wind power farm. When comparison was possible the outcome was that the measurements for roadways matched with the dimensions but measurements for land claims for roads and wind turbines exceeded the dimensions. The values of the measured dimensions vary within and in certain cases between the wind power farms. From the findings of this study it can be concluded that it is difficult to in advance estimate how much land roads and wind turbines in wind farms will claim. In addition the study shows that it is of great importance to specify the dimensions of roadways and land claims for roads and wind turbines in the EIA for wind power farms.
182

A wind energy landscape : the Searsburg Wind Park

Shelley, Dena L. January 2008 (has links)
Wind Energy facilities are becoming a more common occurrence among the U.S. landscape. The shift to renewable from non-renewable energy sources is an important agenda item for energy policy in the 21st century. Unlike other forms of energy, the unique visual aspects of wind energy provide opportunities to engage with and actually view the process of energy production. The sculptural element of turbines and their placement in highly visible areas, such as mountain ridges, provides opportunities of environmental interpretation and public interaction. Although existing security and safety precautions in the U.S. do not allow public use of these facilities, the integration of turbines into public places is becoming more common in other parts of the world. This creative project focuses on developing dynamic and unique cultural places that also serve as education spaces to celebrate wind and wind energy. Environmental art installations among the wind turbines serve as human-scaled interpretational guides to create meaningful, learning experiences between the user, the wind and the landscape.This project highlights the existing eleven-turbine (6MW) facility in the town of Searsburg in southern Vermont. This project includes inventory, analysis and site design of an existing wind facility. The methodology includes using GIS data and existing sight line data, as well as significant and environmental cultural points. Finally, general guidelines are included as a design foundation for other wind energy facilities. / Department of Landscape Architecture
183

Wind Power and Natural Disasters

Olauson, Jon January 2014 (has links)
Wind power can be related to natural disasters in several ways. This licentiate thesis gives some background and introduces four papers devoted to two aspects of this relation. The first section looks into how small-scale wind energy converters (WECs) could be used to generate power after a natural disaster. For this application diesel generators are the most common solution today, but there would be several advantages of replacing these systems. A study of off-grid systems with battery storage at 32 sites showed that photovoltaics (PV) were more suitable than WECs. The results were confirmed by a study for the entire globe; PV outperformed WECs at most sites when it comes to small-scale application. This is especially true for areas with a high disaster risk. Hybrid systems comprising both PV and WECs are however interesting at higher latitudes. For the Swedish case, it is shown that gridded data from a freely available meteorological model, combined with a statistical model, give good estimates of the mean wind speed at 10 meters above ground. This methodology of estimating the mean wind speed can be used when there is no time for a proper wind measurement campaign. The second section is directed towards wind power variability and integration. The results presented in the thesis are intended as a basis for future studies on how a substantially increased wind power capacity affects the electric grid in terms of stability, grid reinforcement requirements, increased balancing needs etc. A review of variability and forecastability for non-dispatchable renewable energy sources was performed together with researchers from the solar, wave and tidal power fields. Although a lot of research is conducted in these areas, it was concluded that more studies on combinations of the sources would be desirable. The disciplines could also learn from each other and benefit from the use of more unified methods and metrics. A model of aggregated hourly wind power production has finally been developed. The model is based on reanalysis data from a meteorological model and detailed information on Swedish WECs. The model proved very successful, both in terms of low prediction errors and in the match of probability density function for power and step changes of power. / Vindkraft kan relateras till naturkatastrofer på flera olika sätt. Den här licentiat\-avhandlingen ger bakgrund till och introducerar fyra artiklar som beskriver två aspekter av detta samband. I den första avdelningen undersöks hur småskalig vindkraft skulle kunna användas för att generera el efter en naturkatastrof. I dagsläget är det dieselaggregat som används för detta ändamål, men det skulle finnas stora fördelar med att övergå till förnybara system. En studie av 32 platser (myndigheten MSB:s utlandsstationeringar augusti 2012) visade att solceller var mer lämpade än vindkraftverk. Resultaten bekräftades av en studie för hela världen; solceller ger billigare system än småskaliga vindkraftverk för de flesta platser, inte minst om man tittar på områden som är utsatta för naturkatastrofer. Hybridsystem med både solceller och vindkraftverk var dock intressanta på högre breddgrader. För Sverige så visas det att data från en fritt tillgängliga meteorologisk modell tillsammans med en statistisk korrigering beroende på terrängtyp ger bra uppskattningar av medelvinden på 10 meters höjd. Den föreslagna metodiken kan vara användbar som ett komplement till vindmätningar eller om det inte finns tid eller möjlighet till en riktig mätkampanj. Den andra avdelningen är inriktad mot vindens variabilitet och integrering av vindkraft i kraftsystemet. De resultat som presenteras i denna avhandling är tänkta som en bas för framtida studier av hur en kraftigt ökad andel vindkraft påverkar elsystemet med avseende på stabilitet, nödvändiga nätförstärkningar, ökade krav på balanskraft etc. En översiktsstudie av variabilitet och prognosbarhet för intermittenta förnybara energikällor gjordes tillsammans med forskare inom sol-, våg och tidvattenkraft. Även om mycket forskning pågår inom dessa områden så var en slutsats att mer studier för kombinationer av olika källor skulle vara önskvärt. Forskare inom de olika disciplinerna skulle också kunna lära från varandra och dra fördel av gemensamma metoder och mått. Slutligen har en modell av aggregerad timvis vindkraftproduktion tagits fram. Modellen baseras på data från en meteorologisk modell samt detaljerad information om vindkraftverk i Sverige. Modellen visade sig vara mycket träffsäker, både vad gäller låga prediktionsfel och i överensstämmelse av sannolikhetsfördelning av effekt och stegförändring av timvis effekt.
184

Planung und Genehmigung von Windkraftanlagen : unter besonderer Berücksichtigung Nordrhein-Westfalens /

Stenneken, Christian. January 2000 (has links) (PDF)
Univ., Diss--Bochum, 1999.
185

Analysis of the measure-correlate-predict methodology for wind resource assessment /

Sheppard, Colin John Ritter. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2009. / Includes bibliographical references (leaves 69-70). Also available via Humboldt Digital Scholar.
186

An economic evaluation of a wind power electricity generating farm in South Africa

Menzies, Greig Hamilton January 2011 (has links)
Renewable energy technology has received much attention over recent years. The depletion of known fossil fuel reserves and the volatility of international fuel prices require that society looks beyond the current coal-dominated electricity generation methods. Wind energy is an internationally well-established technology with large markets in major countries around the world, such as the USA and Germany. South Africa has the potential to generate large amounts of electricity from the wind because of the strength of the country’s wind resource. The long coast line and open areas are ideal for the exploitation of wind energy. A wind farm project has been proposed for development near the town of Jeffrey’s Bay, in the Eastern Cape. The proposed project involves the construction and installation of a 15MW wind farm, consisting of 6-10 turbines standing 120m tall, over an area of 20ha.There are indirect costs and benefits (externalities) associated with a wind farm project and it is important that projects such as these are evaluated from a social standpoint. The aim of this study was to determine the compensation required by residents for siting a wind farm in their area. This compensation was then used as a component of an overall evaluation of the project.
187

INVESTIGATION INTO THE POTENTIAL OF ENERGY PRODUCTION FROM VEHICULAR MOTION INDUCED AIR FLOW IN MALAYSIA

Eramakkaveettil Puthiyakath, Jazeel January 2020 (has links)
With the rise in energy consumption and usage by an exploding human population and higher quality of life, it is time to switch to renewable energy sources that have lower impacts on the natural world. Commercial scale wind power has seen tremendous growth in the last two decades and is expected to continue growing. But small-scale wind power still has tremendous potential in creating energy efficient homes micro-grid systems. Through this work, we explore the potential of micro VAWTs installed on highway medians to capture wind energy from moving vehicles. There are 2 main questions intended to be addressed here, namely: Is energy production from vehicular wake losses significant and if significant, how does the produced energy stand in comparison to a household’s consumption as well as an LED streetlight. In order to proceed with this work, we have taken the reference wind measurements performed on highway medians in Malaysia from literature. The right turbine choice for this application has also been contemplated through the literature review and chosen to be a cross-flow VAWT model with experimental results.Using the power curve of the turbine and the extracted wind speed measurements, energy production is estimated and compared to the electricity consumption of a suburban home in Malaysia. Further on, other analyses are performed to better understand the energy production potential of such applications and estimated for varying size in turbine, position of turbine with respect to ground, and the energy generation per kilometer of highway length.
188

Application of GIS tools in locating onshore wind power plants – A case study of Västmanland County, Sweden.

Li, You January 2013 (has links)
A rapid development of wind energy has been approved globally within the last few years due to the common recognition of this renewable energy technology. It is seen as one of the most promising substitutions to fossil fuels which have been exploited for over one century but were proved to be a crucial factor of human-induced climate change. However, even though wind energy has been regarded to be clean, resource saving and environmentally friendly, it still poses special problems and concerns to the surrounding social-ecological system. Thereby it requires careful selection of sites of installation. This paper provides an overview of wind energy and its development in the recent decade and focus on elaborating different issues involved in wind energy development. This is done through a case study of applying GIS tools in selecting suitable locations for onshore wind power plants in Västmanland County of Sweden.
189

Local states, policy capacity and the sustainability transition: a study of policies for wind energydevelopment in Xinjiang, Shanghai and Guangdong

Mah, Ngar-yin, Daphne., 馬雅燕. January 2010 (has links)
As China has moved towards sustainable development, policies for wind energy have undergone rapid changes over the past two decades in this country. However, although wind energy is capable of making a significant contribution to more sustainable energy systems, it has yet to reach its full potential. There remain significant gaps in knowledge about how and why public policies may effectively facilitate the achievement of sustainability in general and with regard to specific sector-based initiatives. The objective of this study is to bridge this knowledge gap by studying governance for sustainable development with particular reference to wind energy policies in China. This study focuses on the role of Chinese provinces in facilitating the sustainability transition. It proposes a conceptual framework that adopts a policy capacity approach to understanding the sustainability transition process. Policy capacity is defined in this study as the ability to identify, assimilate and utilize resources both inside and outside the formal state apparatus to facilitate the policy-making process. The conceptual framework, which comprises three building blocks – context, process and outcomes – suggests that the interactions between provinces and other stakeholders are the factors that facilitate or constrain policy capacity. A comparative study of the evolution of wind energy policies in three provinces, Xinjiang, Shanghai and Guangdong is presented. The aim of the analysis is to provide a better understanding of the mechanisms that explain whether – and how – provinces represent a key actor in the policy capacity building process. The key findings are first, that while the Chinese provinces may differ in their governing modes, a common feature was that they were in a unique position to strengthen policy capacity through their interactions with the wider society both within and outside the state. Second, the conceptualization of the conducive and inhibitive mechanisms of policy capacity building suggests that there were important conducive conditions for policy capacity building found in the provinces in the form of resources (such as local leadership and trust), structures (such as social ties and bridging structures) and dynamics (such as market dynamics and double-loop learning). However, the provinces’ potential to enhance policy capacity was not fully utilized because of the presence of a set of inhibitive conditions that constrained the efforts. Third, through the conceptualization of the embeddedness of the policy capacity building process, this study reveals that contextual factors, at both the local and national levels, were the key to explaining why provinces differed in their response to the sustainability transition. This study concludes by suggesting that the sustainability transition needs to envision a new governance approach that places more attention on the role of Chinese provinces, to release and activate the enormous capacity in provinces that could in turn strengthen the central government’s own policy capacity for the sustainability transition. / published_or_final_version / Kadoorie Institute / Doctoral / Doctor of Philosophy
190

Optimální řízení větrné elektrárny / Optimal control of a wind power plant

Paděra, Zdeněk January 2011 (has links)
The thesis first provides a brief introduction to wind energy and bring in the current status of this rapidly growing industry. Further, the distribution of wind turbines, their specific and general description of the construction is described. Emphasis is placed on wind turbine control system. The first goal was to build a simulation model of wind power plant in the MATLAB / Simulink usable for subsequent overall design of control system of wind power plant. Furthermore, the analysis of the control of individual components of power station in the light of the possibility of optimizing the operation and in particular the optimization of efficiency of plant, i.e. maximization of the reached performance is performed. In the last part of this thesis structure and parameters of individual control system of plant is designed and the results are discussed.

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