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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.
491

International Competitiveness of the wind power industry : The case of Gamesa S.A.

Batlle, Oriol January 2011 (has links)
The modern lifestyle is highly dependent on the electricity consumption, which demand is expected to continue growing worldwide, especially in those developing areas where the whole economy is transforming. Until now, most of this electricity demand had been supplied through the combustion of fossil fuels or nuclear power. But the utilization of these energy sources to power the human activity is unsustainable because of limitless of the resources and the hazardous emissions and wastes that they generate. That is why since few decades ago the wind power became one of the best-positioned renewable energy in terms of costs effectiveness as a viable alternative to the energetic model based on pollutant fossil fuels. This technology was firstly developed and implemented on those countries with a traditional environmental conscientiousness, but as the global warming issue increased new countries were interested to use wind power as a clean and sustainable energy source. The growing wind power demand of developing countries has changed in few years the entire industry, because new local manufacturers have appeared thanks to the government renewable policy, which main objective is to develop a strong domestic wind power industry capable of lead the world transformation to a clean energy model. The thesis defines the most commons renewable energy policies, and focus in the policy used in China with the aim to analyze if it is promoting or damaging the expansion of wind power use because of the priority is protect its own domestic wind power industry from international firms. The conclusions are that those protectionist policies are useful in the early stage of the industry development but the government must know the exact moment in which these subsidies and supporting mechanisms become counterproductive. If those are used during a prolonged period, then companies become dependent on subsidies and don’t act like in free markets where the innovation is the key to gain and maintain sustainable competitive advantage.
492

Analysis of AEP prediction against production data of commercial wind turbines in Sweden

Sugathan, Aromal, Gregory, Sean January 2021 (has links)
Based on data from 2083 wind turbines installed in Sweden since 1988, the annual energy production (AEP) predictions considered at the project planning phases of the wind turbines in Sweden have been compared to the wind-index-corrected production data. The production data and the predicted AEP data are taken from Vindstat, a database that collects information directly from wind turbine owners in Sweden. The mean error for all analyzed wind turbines was 11.9%,which means that, overall, the predicted AEP has been overestimated. There has been improved accuracy with time and error in prediction decreasing from 12% to 6.3% for wind turbines installed in the 2000s and 2010s, respectively. However, the overall improvement in accuracy seems to have stagnated around 2005 despite the refinement of forecasting methods and better data availability. From the results analyzed for effects of terrain, the error is smaller for wind turbines in forest areas than in open terrain, indicating that the complexity of forest terrain is not the reason behind the error. Also, there is no apparent increase of error with wind farm size, which could have been expected if the wind farm blockage effect was a primary reason for the overestimations. Comparison between significant wind turbine manufacturers Vestas and Enercon in the Swedish context, the error was more prominent for Enercon.
493

Potentialen av solcellsetablering i vindkraftsparker / The potential of PV establishment in wind farms

Nilsson, Emelie January 2021 (has links)
This degree project aims to investigate whether it is possible to establish photovoltaic (PV) systems inexisting Swedish wind farms from a production and permit perspective. The degree project examinesthe conditions for the establishment of PV systems in three wind farms owned by Eolus Vind AB. The results show the importance of investigating the prerequisites of the location to find the rightproject site for PV power plants. In addition, the results show that Swedish laws do not oppose PVpower plants being built in wind farms. The production calculations also show that a more evenelectricity power production is achieved when PV systems are installed on open areas in the windfarms, but that the proportion of installed power will be limited by the connection points within eachwind farm. The conclusion is that wind farms are suitable with a combination of solar and wind power, but theconnection point will be a major factor in the amount of installed solar power that can be added to theproject areas.
494

Energy Crisis : wind Power Market in China

Kuang, Chen, Ying, Jin, Yumin, Li January 2013 (has links)
Purpose/aim The aim is to explore which price policy of the Chinese wind power is the most suitable for the market. Design/methodology/approach Data has been collected through questionnaires. The analysis includes the statistical test in form of chi-square. Additionally the whole thesis followed the onion process put forward by Saunders. Findings The analysis showed that the price policy which is based on the local price of coal is more suitable for the market than the price policy decided by concession projects. Originality/value An original idea is given the relationship between ages, education levels and two policies. Further, the empirical data is collected from a comprehensive online-forum, so that the samples are randomly selected. The data shows that the businesses which want to enter the Chinese wind power market should choose the price policy which is based on the local price of coal. This choice should be useful in the real life.
495

Wind Power Expansion: “Land-grabber” or Local Catalyst? : A mixed-method thesis on the Swedish renewable energy transition and the “social gap” between the global and the local

Johansson, Viktor January 2021 (has links)
This thesis examines Sweden’s transition towards a 100% renewable energy system in 2040, by analyzing the expansion of wind power in particular. The study applies a theoretical framework consisting of the concepts of Social Acceptance and Ladder of Participation to analyze how these can be applied on the national and local levels. As the purpose is to acknowledge the different opportunities and problems with the ongoing expansion of wind power and to identify if the “social gap” between global and local is present in Sweden, both qualitative and quantitative methods are applied. Content analysis was used to examine the role of social acceptance and citizen participation while the Pearson Correlation Analysis was conducted to identify possible connections between the public’s attitudes towards wind power and the increasing number of wind turbines on different scaling levels. The results identified differences in quality and quantity of the approach strategies used to increase social acceptance and citizen participation on the national and local levels. Strong resistance movements were also found on the local level, while no moderate nor strong relationship could be found between the public’s attitudes and the number of turbines, instead, strong support was found on all geographical levels, hence, the “social gap” is present in the Swedish context. The thesis also concludes that if implemented wrong, wind power could be considered as a “land- grabber” while the opposite is true if done right, and thus function as a local catalyst.
496

The Role of Municipal Planning in the Permit Decisions on Large Onshore Wind Power Projects in Sweden

Abboud, Sarah January 2021 (has links)
Sweden wants to produce 100% of its electricity from renewable energy sources by 2040 and achieve net zero greenhouse gas emissions by 2045. While wind power is key to this transition, the permit process for large onshore wind power projects is one of the major challenges the country is currently facing, specifically the provision on municipal approval in the Environmental Code, the so-called municipal veto. To facilitate the expansion of wind projects in Sweden, the double testing of wind power applications was abolished in 2009, and the municipal veto was introduced to preserve the municipalities’ planning influence. However, the municipal veto contributed to a less predictable and legally secure permit process and became the main reason behind the rejections of wind power applications. Today, in 2021, the Swedish Government assigned a special investigator to examine and propose possible changes to the municipal veto provision. Though the municipalities believe that the veto is essential for their self-government and planning monopoly, the Swedish Energy Agency and the Swedish Environmental Protection Agency argue that the municipal authority should be exercised through the municipal general planning documents. Therefore, this thesis aims to verify the authorities’ argument by examining the relationship between the municipalities’ planning conditions for wind power and the permit decisions. The study is performed in collaboration with Westander Klimat och Energi and is based on 206 large onshore wind power applications between 2014 and 2020. The main research methods consist of a document analysis and of statistical analyses, namely simple percentages, and the chi-square test of independence, along with Cramer’s V calculation. The projects are categorized mainly based on the municipal planning conditions, and the permit decisions are analyzed accordingly. Essentially, it is shown that, even if not legally binding, the municipal general spatial planning documents constitute a valuable tool for the planning of onshore wind power projects in Sweden. Furthermore, the municipal planning conditions and permit decisions are not independent, however, their strength of association is weak. Nonetheless, the statistics indicate that in areas designated as suitable, more cases are likely to receive an approval than expected, and in areas not designated as suitable, the applications are more likely to be revoked than one would expect. In conclusion, it is important to invest resources into the strategic wind power planning at the local level. Also, the municipal plans must be kept updated to consistently reflect the municipalities’ intentions towards the use of their land and water areas.
497

A Two-Stage Data Envelopment Analysis Model for Efficiency Assessments of 39 State's Wind Power in the United States

Sağlam, Ümit 01 January 2017 (has links)
The average global surface temperature increased by 0.85 °C since 1850 because of irrepressible increase of the concentration of greenhouse gases (GHG). Electricity generation is the primary source of GHG emissions in the United States. Hence, renewable energy sources, which produce a negligible amount of GHG emissions, have gained enormous attention, especially in the electricity generation sector over the past decade. Wind power is the second largest renewable energy source to generate electricity in the United States. Therefore, in this study, a two-stage Data Envelopment Analysis (DEA) is developed to quantitatively evaluate the relative efficiencies of the 39 state's wind power performances for the electricity generation. Both input- and output-oriented CCR (Charnes, Cooper, and Rhodes (1978)) and BCC (Banker, Charnes, and Cooper (1984)) models are applied to pre-determined four input and six output variables. The sensitivity analysis is conducted to test the robustness of the DEA models. Tobit regression models are conducted by using the DEA results for the second stage analysis. The DEA results indicate that more than half of the states operate wind power efficiently. Tobit regression indicates that early installed wind power was more expensive and less productive relative the currently installed wind power. Findings of this study shed some light on the current efficiency assessments of the states and the future of wind energy for both energy practitioners and policy makers.
498

Åtgärder som skapar samsyn vid vindkraftsetableringar : Kommunikation och dialog med lokalbefolkningen / How to create public acceptance for wind power projects : Communication and dialogue with the public

Rudolfsson, Elin January 2015 (has links)
Sveriges regering har tagit fram en nationell planeringsram för vindkraft som inkluderar 30 TWh installerad effekt år 2020. Negativa attityder mot vindkraft kan dock bromsa upp och hindra specifika vindkraftsprojekt, vilket skapar en utmaning för att uppnå målen. En problematik för vindkrafts­projektörer i Sverige är att även om majoriteten av lokalbefolkningen är positivt inställda till en etablering, kan det vara tillräckligt att en person agerar rättsligt för att ett projekt ska fördröjas eller hindras. Motstånd mot vindkraft baseras ofta på subjektiva uppfattningar, vilket innebär att det är svårt att hitta en generell lösning för att öka acceptansen bland lokalbefolkningen. Ibland baseras motståndet på den lokala påverkan en vindkraftsanläggning förväntas medföra medan det i andra fall snarare är ett motstånd mot de som driver ett projekt eller det sätt projektet genomförs på. Denna studie syftar till att kvalitativt undersöka hur lokalbefolkningens acceptans till vindkraftsprojekt påverkas av kommunikationen i planerings- och prövningsprocessen, samt identifiera åtgärder som kan öka acceptansen för nyetableringar av vindkraft. Detta har utförts med hjälp av intervjuer med projektörer, myndigheter och konsulter som delgivit sina tidigare erfarenheter från olika vindkrafts­projekt. Informationen har sammanställts och kopplats till teorier kring attityder och kommunikation för att sedan resultera i en rekommendation för projektörers framtida arbete. Studien har resulterat i bland annat ett antal faktorer som kan påverka acceptansnivån och attityderna hos lokalbefolkningen, som därmed är viktiga för projektören att ta hänsyn till i kommunikationen med de närboende. En vindkraftsetablering innebär för många en förändring av närområdet och kan skapa en känsla av oro för hur etableringen ska påverka människor och miljö. En etablering kan även skapa en känsla hos de närboende av att de inte har kontroll och bestämmanderätt över sin närmaste omgivning och livssituation. Oro samt känslan av att sakna kontroll kan skapa negativa attityder och bör därför fokuseras på under projektet. Ett sätt att erbjuda lokalbefolkningen kontroll är att involvera dem i projektet samt förklara samråds- och tillståndsprocessen. Ett sätt att stilla oro är att delge de närboende saklig och korrekt information kontinuerligt under hela projektet. Det är viktigt att involvera lokalbefolkningen för att de inte ska känna sig åsidosatta, men om lokalbefolkningen involveras är det viktigt att deras åsikter har en reell effekt på etableringen. Människor litar på information de får från en tillitsfull person. Därför är det viktigt att projektören inger förtroende och vinner tillit från lokalbefolkningen. Detta kan fås genom att ha en ärlig, öppen och respektfull kommunikation. Det är även viktigt att projektörer visar att de tar hänsyn till och lyssnar på lokalbefolkningens åsikter och oro, oavsett om dessa är relevanta för tillståndsprövningen eller inte. Det är viktigt med en tidig och proaktiv kommunikation då studiens resultat påvisat att det är svårt att förändra negativa attityder. Om människor bygger en negativ attityd på felaktig information, rykten eller spekulationer är det svårt att ändra dessa attityder i efterhand. Därför är det viktigt att aktivt informera människor tidigt i processen. Projektören bör tidigt i processen kartlägga intressenter och deras eventuella oro i syfte att sammanställa en kommunikationsplan. Resultaten visar tydligt att ett utställningssamråd har större förutsättningar att skapa en lokal förankring för ett projekt än ett presentationssamråd. Vid ett presentationssamråd är det svårt för alla människor att komma till tals och ställa sina frågor eller lämna synpunkter. Vid en utställning sker en dialog mellan projektörer och närboende, vilket innebär att samtalet kan fokusera på den enskilde individens oro. Risken för feltolkningar och missförstånd minskar då projektören kan anpassa dialogen till den närboende. Övriga åtgärder som kan öka acceptansen för vindkraftsprojekt är bland annat ekonomisk ersättning och fältbesök. Ekonomisk ersättning kan ge en individuell tillfredställelse. Fältbesök och liknande åtgärder kan ge de närboende nya erfarenheter av vindkraft, vilka kan stilla lokalbefolkningens oro och därmed påverka attityden mot specifika vindkraftsetableringar positivt. / The Swedish government has established a national planning framework for wind power, including a goal of 30 TWh of installed capacity by 2020. It has however been proven difficult to reach these goals since negative attitudes towards wind power projects can hinder the development. One main issue is that even though the majority of the local community is positive to a wind power establishment, it can be enough that one person take legal action against it for the project to be interrupted. Resistance towards wind power is often subjective which means that it is difficult to find a general solution to increase the acceptance among the local community. People often resist the local impact wind turbines might cause, but the resistance could also be towards those who carry out the project or how the project is conducted. This study aims to qualitatively investigate how communication throughout the planning- and permission process affect the level of acceptance among the local community, as well as to identify measures which can raise the acceptance for wind power projects. Interviews have been conducted with project planners, authorities and consultants in order to gather their experiences from previous projects. This information has been related to theories regarding attitudes and communication and has resulted in a recommendation of how future projects should be conducted in order to raise the local acceptance. The study results in several factors that affect the level of acceptance and the attitudes among the local community. These factors are important for the project planner to take into account when communicating with the public. A wind power establishment is for many people a huge change in the surroundings, and can create a feeling of worry and anxiety related to how the establishment will affect humans and the environment. A project might also cause a feeling of not being in control. These two feelings can create negative attitudes towards a project. One way to create a feeling of control is to involve the local community in the project and to explain for them the process of planning a project and applying for permission. In order to ease worries, the project planner should share objective and accurate information. People tend to trust the information they receive from a person they consider trustworthy. Therefore it is important for the project planner to act in a trustworthy manner, for example by being honest and to use a transparent and respectful communication. It is also important that the project planner listen to the public’s opinions and worries, even though they are not relevant for the permission process. The study proves the difficulty of changing already negative attitudes, which emphasise the importance of an early and proactive communication. If people create a negative attitude based on false information, rumours or speculations, it is hard to change their attitudes afterwards. Therefore it is important to map actors in the community and their potential worries, with the purpose to construct a communication plan. The results clearly indicate that a consultation meeting in the shape of an exhibition instead of a presentation has a higher potential for creating a local acceptance towards a project. With only a presentation not everyone will have their saying. An exhibition enables a dialogue between the project planner and individual inhabitants where opinions and questions can be more easily communicated between the parties. The project planner can also easily adapt the dialogue to decrease the risk of misperceptions and confusions. Other measures that can increase the level of acceptance are economical compensation as well as field trips, where the inhabitants can create their own opinion of the impact from wind turbines. It can ease worries and thereby create positive attitudes towards wind power projects.
499

REMANUFACTURING IN WIND POWER: A MULTI CRITERIA DECISION ANALYSIS APPROACH

Robertson, Graeme January 2020 (has links)
Due to the rapid growth of the wind energy market over the last decade, the future of the industry will consequently see the dismantling of many wind turbines, both due to wind turbines reaching the end of their service life and to make way for surpassing technology, leaving behind a large amount of material that must be dealt with. Furthermore, due to the advancing technology of wind turbines, there has been a decline in the number of medium sized wind turbines being manufactured. This study aims to address the problem of future waste mitigation, whilst attempting to capture the medium scale market. As such, the study has looked at the idea of transitioning towards a circular economy, in which wind turbines are not considered as waste at the end of their service life, but rather an opportunity to recapture value through remanufacturing. This was approached by identifying the driver and barriers of remanufactured products, utilising knowledge from other industries with developed remanufacturing sectors. A Multi-Criteria Decision Analysis (MCDA) has been performed using the PROMETHEE II method with the objective of drawing a comparison of three scenarios, enveloped by a theoretical wind turbine selection project. The scenarios were created by the author and considered the implementation of a new wind turbine and remanufactured wind turbines. Upon examining the results of the multi criteria decision analysis, it was seen that the benefits of implementing remanufactured turbines were preferred by the majority of the stakeholders involved.
500

Identification of Markov Processes within a Wind Turbine Array Boundary Layer

Melius, Matthew Scott 23 August 2013 (has links)
The Markovianity within a wind turbine array boundary layer is explored for data taken in a wind tunnel containing a model wind turbine array. A stochastic analysis of the data is carried out using Markov chain theory. The data were obtained via hot-wire anemometry thus providing point velocity statistics. The theory of Markovian processes is applied to obtain a statistical description of longitudinal velocity increments inside the turbine wake using conditional probability density functions. It is found that two and three point conditional probability density functions are similar for scale differences larger than the Taylor micro-scale. This result is quantified by use of the Wilcoxon rank-sum test which verifies that this relationship holds independent of initial scale selection outside of the near-wake region behind a wind turbine. Furthermore, at the locations which demonstrate Markovian properties there is a well defined inertial sub-range which follows Kolmogorv's -5/3 scaling behavior. Results indicate an existence of Markovian properties at scales on the order of the Taylor micro-scale, λ for most locations in the wake. The exception being directly behind the tips of the rotor and the hub where the complex turbulent interactions characteristic of the near-wake demonstrate influence upon the Markov process. The presence of a Markov process in the remaining locations leads to characterization of the multi-point statistics of the wind turbine wakes using the most recent states of the flow.

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