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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.
251

Offshore power production and marine stakeholders : from understanding conflict to impact mitigation

Alexander, Karen January 2012 (has links)
Little is known about the impact of marine renewable energy installations upon the marine environment and those who use it. Harnessing marine energy will involve the offshore siting of energy extraction devices and their associated infrastructure. This will alter the local environment and substantially modify use and access for a variety of marine stakeholders, potentially leading to conflict. Using the Ecosystem Approach (EA) as a conceptual framework, this thesis aimed to answer the question: What is the potential for conflict between the marine renewable energy industry and marine stakeholders, and how can this be mitigated? The research consisted of three components which used a variety of methods: i) stakeholder identification through a review of the literature and use of a novel interactive mapping method; ii) an investigation of the potential consequences for the priority stakeholder which used a mail survey and in-depth interviews; and iii) an exploration of potential mitigation which used ecosystem modelling. The stakeholder most likely to be affected by marine renewable energy device (MRED) deployment was the fishing industry. Potential consequences included: navigation and safety hazards, loss of access and alternative employment. Further exploration revealed that a loss of livelihood was the all-encompassing concern for fishers, and that skills shortages (transferable skills) may mean that should a loss of livelihood occur there may not be acceptable alternative employment. The modelling exercise indicated that it is not currently possible to definitively predict whether any opportunities which may be created by MRED installation will mitigate any negative effects, and that exclusion zones may actually decrease catches for most fleets. The findings of this study have implications for ‘conflict-free’ development of the marine renewable energy industry. To address this, several policy recommendations were offered as regards to operationalising the EA in terms of marine renewable energy.
252

The Impact of Wind Power Production on Electricity Price Volatility : A Time-Series Analysis

Wirdemo, Alexander January 2017 (has links)
This study investigates how increased wind power production (in MWh) in Sweden has affected electricity price volatility in the Nordic wholesale electricity exchange Nord Pool. The importance and growth of wind power have emerged in light of its low marginal costs of production and it being a renewable, zero-carbon electricity generation source. Previous studies have found that while increased wind power production generally lowers the average wholesale price of electricity, volatility tends to increase due to the intermittent character of wind power production. By using daily price and wind power data from the Nordic exchange market Nord Pool during the period 2015-2017, a GARCH model was used to investigate how wind power has affected price volatility. The results indicate that electricity price volatility increases in the long run when wind power production increases. The reasons behind this could be found in the inflexibility of baseload power production. However, the Swedish electric power system also benefits from a high degree of flexibility due to the presence of hydropower reservoirs.
253

PUBLIC ATTITUDE TOWARDS WIND POWER IN A DEVELOPED AND A DEVELOPING WIND MARKET – CASE STUDY OF SPAIN AND POLAND

Gulatowski-Henk, Marcin January 2017 (has links)
Wind power is currently one of the main sources of renewable energy worldwide. However, despite its numerous advantages, the deployment of wind turbines is not free from encounters with resistance from the society. This report reviews the principal aspects of the public attitude towards wind power. The research aims to define similarities and differences in attitude between residents of a developed and a developing wind market in Europe, Spain and Poland, respectively. A survey reveals that responses from both groups are similar in terms of the strategies employed by wind developers. The highest discordance is found within aspects of wind technology, such as the aesthetics of wind turbines and the perceived cost of wind power.
254

ONSHORE WIND FARM REPOWERING ALTERNATIVE SCENARIOS AND COST ASSESSMENT

Al Hamed, Hassan January 2021 (has links)
Many reasons to consider extending the useful time of ageing wind farms. Like to take advantage of it being located in a good wind source, besides existing infrastructure, etc. Repowering can be an appropriate option for the ageing wind farm that suffering less yield energy and increment of cost of operation and maintenance.  The thesis discusses the repowering potential of old wind farms. The case study is implemented on a selected wind farm in Denmark. Different repowering scenarios were considered with the technical-economic assessment for each scenario to determine which scenario is viable. The sensitivity analysis was done taking into consideration selected parameters to find out the effect of each parameter on the profitability and productivity of the repowered wind farm. More details will be explored in the following chapters.
255

Essays in Energy and Environmental Economics

Atal Chomali, Raimundo January 2021 (has links)
This dissertation represents an effort to advance interdisciplinary research in issues relevant for energy and environmental policy, combining economics with applied engineering and ecology. It includes work that is informed by theoretical and empirical studies, and is conceptually centered in the notion that competitive markets lead to inefficient combinations of risk and yield. In the first two chapters of the dissertation, I study this in the context of wind energy capacity investments, where profit-maximizing developers choose the location and timing of the construction of wind farms. The final chapter of the dissertation is an empirical study on the effects of intensive aquaculture on water pollution.
256

Probabilistic Forecast of Wind Power Generation by Stochastic Differential Equation Models

Elkantassi, Soumaya 04 1900 (has links)
Reliable forecasting of wind power generation is crucial to optimal control of costs in generation of electricity with respect to the electricity demand. Here, we propose and analyze stochastic wind power forecast models described by parametrized stochastic differential equations, which introduce appropriate fluctuations in numerical forecast outputs. We use an approximate maximum likelihood method to infer the model parameters taking into account the time correlated sets of data. Furthermore, we study the validity and sensitivity of the parameters for each model. We applied our models to Uruguayan wind power production as determined by historical data and corresponding numerical forecasts for the period of March 1 to May 31, 2016.
257

Ecological and Sociological Considerations of Wind Energy: A Multidisciplinary Study

Bicknell, Lucas J. January 2012 (has links)
Wind energy is quickly becoming a critical technology for providing Americans with renewable energy, and rapid construction of wind facilities may have impacts on both wildlife and human communities. Understanding both the social and ecological issues related to wind energy development could provide a framework for effectively meeting human energy needs while conserving species biodiversity. In this research I looked at two aspects of wind energy development: public attitudes toward wind energy development and wind facility impacts on local bat populations. These papers present aspects of wind energy development that have been the subject of increasing study. This preliminary research is intended to demonstrate the responsibility we have to making well-informed decisions as we continue to expand wind energy development. Additionally, I hope to generate interest in interdisciplinary study as a means to broaden the scope of research by making use of the diverse tools available within different disciplines.
258

Wind Energy Assessment in Africa; A GIS-based approach

Mentis, Dimitrios January 2013 (has links)
This study analyses the potential of onshore wind power on the African continent. Appropriate socio-economic and geographical constraints as well as current technology’s efficiencies are applied in order to reach the desired result. The current energy access in Africa is described to illustrate the need of promoting the wind power penetration on the continent. The existing as well as the under construction wind farms are mapped. Thereafter, the methodology of approaching the resource assessment is analyzed. For the energy generation assessment, not only wind speed strength but also its probability of occurrence over a certain period of time is important and thus considered in this study. High resolution wind speed data from Vortex and lower resolution daily wind speed data are combined and processed in order to obtain a fine wind speed distribution and thus wind energy production generated by selected wind turbine models. The different categories of wind power potential are defined and evaluated. Additionally, screening criteria regarding the localization of wind farms are outlined and implemented through GIS analysis. Subsequently interactive maps are prepared. ArcGIS software is used in order to capture, store and manipulate the required data and to obtain a holistic view of the study. The study is conducted at a continental level using a 1km×1km (longitude, latitude) land-use grid as the finest resolution. Ultimately the results of this work are presented and compared with similar approaches and significant conclusions are drawn. Based on the analysis there are some countries that signify high yearly wind energy yield, such as South Africa, Sudan, Algeria, Egypt, Libya, Nigeria, Mauritania, Tunisia and Morocco, whilst Equatorial Guinea, Gabon, Central African Republic, Burundi, Liberia, Benin and Togo indicate the least wind power potential. Also important future work is suggested. / Denna studie analyserar potentialen för landbaserad vindkraft på den afrikanska kontinenten. Lämpliga socioekonomiska och geografiska begränsningar samt aktuella vindkraftverkens effektkurvor tillämpas för att nå det önskade resultatet. Den nuvarande tillgången till energi i Afrika beskrivs för att illustrera behovet av att främja vinkraftens penetration på kontinenten. De befintliga vindkraftverken såväl som de under konstruktion kartläggs. Därefter analyseras metoden för att närma sig resurs bedömningen. Bedömningen av energiproduktion och vindhastighet samt dess sannolikhet att inträffa under en viss tid är både viktigt och nödvändigt för denna studie. De olika kategorierna av potential för vindkraftverk definieras och utvärderas. Dessutom beskrivs kriterier av lokalisering för vindkraftverk och genomförs genom GIS-analys. Därefter förbereds interaktiva kartor. ArcGIS software används för att fånga, lagra och manipulera data som krävs samt för att få en helhetssyn av studien. Studien genomförs vid en kontinental nivå genom att använda en 1 km x 1 km (longitud, latitud) rutnät för markanvändning med den finaste upplösningen. Slutligen presenteras resultaten av detta arbete och jämförs med liknande metoder, viktiga slutsatser dras samt viktigt framtida arbete föreslås.
259

Wind farm noise impact in France: A proposition of acoustic model improvements for predicting energy production

Keller, William January 2014 (has links)
Despite all environmental and economic advantages of wind power, noise emission remains an issue for population acceptance. In France, the current noise emission regulation defines noise emergence level thresholds, leading to wind turbine curtailment. Great energy generation losses and thus lost revenues are at stake. This master thesis presents current acoustic campaigns conducted for the development of a wind power project in France and proposes acoustic model improvements to predict curtailment losses before the construction of the wind farm. It first gives insights about the French wind power context and a literature review of available technologies to reduce noise emission from the blades. It then presents the particularities of French regulation of emergence levels and the use of the norm NFS 31-114 during the commissioning acoustic control. It explains the current acoustic model used at the development stage to predict noise emission and curtailment and finally proposes improvements such as considering the topography, the environmental characteristics and the use of uncertainties.
260

How to develop onshore wind farm projects in France under the new Grenelle 2 law

BAUDREY, Xavier January 2012 (has links)
With the rising global warming issue and an ever-increasing dependency oil problem, wind power seems to be an alternative source of energy which is clean, non-polluting, and cost effective. The European 20-20-20 goals as well as national targets for the next ten years require a substantial increase in installed renewable capacity in France. Maïa Eolis is a leading French wind project developer and independent renewable energy producer which helps France to meet its new renewable energy targets. Even if the general opinion on wind energy is rather positive, developing a wind power project is a complex process in France because there are many regulations and new environmental constraints due to the Grenelle 2 law. Many administrative and legislative barriers consequently slow down every step of the development process. This includes handling and coordinating the permitting and application process, realizing pre-feasibility studies, and identifying the best suited sites for wind turbines, taking into account obstacles, aesthetics, and other environmental issues, in order to capture as much wind as possible. Ensuring local support is another key element of the success of a project in order to integrate it in the best possible way in its environment.

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