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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.
151

WindSim Study of Hybrid Wind Farm in Complex Terrain

Hines, Paul January 2012 (has links)
A annual nergy production analysis was undertaken to compare wind resources and annual energy production as estimated by WAsP and Windsim. Nordex Sverige AB has designed a wind farm with the help of WAsP and this study will involve the examination of this site with Windsim. Two site formations are of interest, one with the same class of turbine and one with a mix of two turbine types. The study is interested in the effect on annual energy production as estimated by the different software of employing a hybrid layout using wind turbines of different height.The results showed that whilst initial estimations of total energy production without wake losses appear very similar between WAsP and Windsim the ways in which the software are treating individual turbines within the planned farm can be quite different because of different physics. The analysis of the „hybrid‟ turbine layout showed significant increases in estimated annual energy production when a turbine with a higher tower and larger rotor diameter was used in a hybrid arrangement. Estimated annual energy losses on the turbines that were not changed in favour of a larger turbine were small. However, no great benefit in estimated turbine efficiency was achieved through the mixing of turbine types with different hub heights. The gains in annual energy production estimated by both software are however significant with increased production of 18 % across the entire farm when comparing the „hybrid‟ layout to a farm based on only the smaller of the two turbine types.
152

Project Finance in the Energy FieldCase Study: A wind Power Project in a Moroccan-like environment

ABDOUSSI, Sarah January 2013 (has links)
Companies, governments and NGOs are involved in designing and planning the future energy landscape of countries. Engineers and scientists contribute highly to this planning through bringing innovative, efficient and reliable technical solutions. Their know-how is used during the project development, the EPC (Engineering, Procurement and Construction) phase as well as during the Operation and Maintenance stage. However, a successful energy plan depends on many other parameters such as the legal side, the political background of the country, the financing methods, the funding, the environmental aspects and the social acceptance. This Master Thesis Project focuses on the financing side of energy projects, which is a key point to properly manage competitive and viable projects. The strong link between the financing and the political background will be shortly commented throughout the report. In the first part of the report, the focus is put on the Project Finance. All along the report, the theoretical concepts will be illustrated with examples taken from the EDF EN projects, mainly in the Middle East and North African area. The second part deals with the risks associated to power projects. Commercial and political risks are listed and the main mitigation tools are explained. The third part of the report is dedicated to basic business models for energy projects. A simplified economical and financial model is described in detail and run for a wind farm project in a Moroccan-like environment. A sensitivity analysis (fourth part) concludes the report through analyzing: - the impact of technological choices on the internal return on investment will be studied - the impact of the financial parameters on the project structure.
153

The field performance of a windmill powered sprinkler irrigation system.

Ionson, John Malcolm. January 1969 (has links)
No description available.
154

Wind energy with emphasis on reduced air pollution

Hargraves, William Ray 08 1900 (has links)
No description available.
155

SIMULTANEOUS MITIGATION OF SUBSYNCHRONOUS RESONANCE AND SUBSYNCHRONOUS INTERACTION USING FULL-SCALE FREQUENCY CONVERTER- AND DOUBLY-FED INDUCTION GENERATOR-BASED WIND FARMS

2014 May 1900 (has links)
Subsynchronous Resonance (SSR) is one of the major obstacles for the wide spread of high degrees (60% and higher) of series capacitor compensation. Recently, a new obstacle, namely Subsynchronous Interaction (SSI) has been added to the list after the Zorillo Gulf wind farm incident in Texas in October 2009. SSI is due to the interaction between large Doubly-Fed Induction Generator (DFIG)-based wind farms and series capacitor compensated transmission systems. In integrated power systems incorporating series capacitor compensated transmission lines and high penetration of wind energy conversion systems, especially DFIG-based wind farms, SSR and SSI could occur concurrently as a result of some system contingences. Therefore, mitigating SSR and SSI is an important area of research and development targeting at developing practical and effective countermeasures. This thesis reports the results of digital time-domain simulation studies that are carried out to investigate the potential use of Full-Scale Frequency Converter (FFC) and DFIG-based wind farms for simultaneous mitigation of SSR and SSI. This is achieved through introducing supplemental control signals in the reactive power control loops of the grid side converters of the DFIG and/or the FFC wind turbines. In this context, two supplemental controls designated as Supplemental Controls 1 and 2 are examined. Supplemental Control 1 introduces a signal in the grid side converter of the FFC wind turbines to damp both SSR and SSI oscillations. On the other hand, Supplemental Control 2 introduces a signal in the grid side converter of the FFC wind turbines for damping SSR oscillations and another signal in the grid side converters of the DFIG wind turbines for damping SSI oscillations. Time-domain simulations are conducted on a benchmark model using the ElectroMagnetic Transients program (EMTP-RV). The results of the investigations have demonstrated that the presented two supplemental controls are very effective in mitigating the SSR and SSI phenomena at different system contingencies and operating conditions.
156

Wind power integration in island-based smart grid projects : A comparative study between Jeju Smart Grid Test-bed and Smart Grid Gotland

Piehl, Hampus January 2014 (has links)
Smart grids seem to be the solution to use energy from renewable and intermittent energy sources in an efficient manner. There are many research projects around the world and two of them are Jeju Smart Grid Test-bed and Smart Grid Gotland. They have in common that they are both island-based projects and connected to the Powergrid on the mainland by HVDC-link. The purpose of this thesis is to compare the two projects and find out what challenges and strategies they have related to wind power integration. The objective of the two projects were somewhat different. Jeju Smart Grid Test-bedare the starting point for South Korea’s smart grid road map, where the objective ultimately is to construct a smart grid on a national scale in South Korea. For Smart Grid Gotland there are three main focus areas; electricity market, power quality and wind power integration. In this thesis focus is on wind power integration. Wind power integration in smart grids would benefit from energy storage technology connected to the wind power-park to even out the power output. Properties for a potential energy storage connected to Näsudden wind power park situated on the southern tip of Gotland has been investigated and the result is that such an energy storage would likely need to be big and expensive, but able to stabilize the power output.
157

Sizing storage and wind generation capacities in remote power systems

Gassner, Andy 18 October 2011 (has links)
Global adoption of renewable energy is increasing due to growing concern over climate change, increasing costs associated with conventional generation, and decreasing capital investment costs of renewable energy technologies. Specifically, wind power represents the most technologically mature renewable alternative and is recognized as a cost effective generation source in both large and small power systems. However, the variability due to the stochastic nature of the wind resource introduces technological limitations to the amount of wind power which can be integrated in a power system. Energy storage is seen as a solution to mitigate the variability in wind power output. Wind power and energy storage devices have the potential to contribute a substantial amount of renewable generation to meet the electricity demand in remote power systems. Remote power systems are characterized by their self reliance on electrical generation. The basic function of a remote power system is to provide the necessary power to satisfy the community’s electricity demand requirements as economically as possible with an adequate level of continuity and reliability. / Graduate
158

A tall tower wind investigation of northwest Missouri

Redburn, Rachel. January 2007 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on January 8, 2008) Includes bibliographical references.
159

The technologies and principles needed for the powering of remote nodes in an interoperability network

Beidalah, Chadrick J. Coudray, Aaron D. January 2009 (has links) (PDF)
Thesis (M.S. in Information Technology Management)--Naval Postgraduate School, March 2009. / Thesis Advisor(s): Buddenberg, Rex. "March 2009." Description based on title screen as viewed on April 24, 2009. Author(s) subject terms: Power Generation, Remote Network Node, Interoperability Network, Electric Generator, Wind Power, Solar Power, Photovoltaic, Thermoelectric, Energy Storage, Fuel Cell, Hybrid Power, Power Monitoring, Power Management. Includes bibliographical references (p. 117-120). Also available in print.
160

Assessment of bat mortality and activity at Buffalo Mountain Windfarm, Eastern Tennessee

Fiedler, Jenny K. January 2004 (has links) (PDF)
Thesis (M.S.)--University of Tennessee, Knoxville, 2004. / Title from title page screen (viewed Sept. 22, 2004). Thesis advisor: David Buehler. Document formatted into pages (xiv, 166 p. : ill. (some col.), maps (some col.)). Vita. Includes bibliographical references (p. 79-93).

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