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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.
261

Totara Valley micro-hydro development : a thesis presented in partial fulfillment of the requirements for the degree of Master of Applied Science in Renewable Energy Engineering, Massey University, Palmerston North, New Zealand

Donnelly, David Ronald Unknown Date (has links)
This study focuses on the design, construction and operation of a distributed generation system based on micro-hydro technology. The project is sited in the Totara Valley, a small rural community approximately 70km from the Massey University, Turitea campus, Palmerston North. The Massey University Centre for Energy Research (MUCER) has a long history of renewable energy research within the Totara Valley community. This project complements these existing schemes and provides a foundation for future research into distributed generation technologies. The project encompasses the following objectives: - to gain practical experience in the design, engineering and implementation of a distributed generation system in rural New Zealand; - to evaluate contemporary micro-hydro technology and compare the performance of this equipment in a theoretical and practical context; - to identify barriers that hinder the widespread adoption of micro-hydro systems in rural New Zealand; - to develop a spreadsheet based life cycle costing tool. The results from this study demonstrate that economic considerations are the fundamental aspect to be considered when assessing the long-term viability of these projects. The viability of micro-hydro projects are primarily determined by four factors: - the volume and head (height) of water available above the turbine site; - the length and therefore the cost of the pipeline required for transporting water to the turbine; - the legal and administrative costs involved in obtaining a resource consent to maintain access to the water resources; - the prices received and paid for electricity. Considerable charges were payable to the local authority to secure and maintain the right to harness the water resources at this site. This cost contributed considerable risk to the project and creates a significant barrier to establishing similar systems at other sites. The reduction of resource consent charges to levels that fairly reflect the negligible environmental impacts of these projects would encourage the adoption of this technology and deliver benefits to rural New Zealand communities.
262

Totara Valley micro-hydro development : a thesis presented in partial fulfillment of the requirements for the degree of Master of Applied Science in Renewable Energy Engineering, Massey University, Palmerston North, New Zealand

Donnelly, David Ronald Unknown Date (has links)
This study focuses on the design, construction and operation of a distributed generation system based on micro-hydro technology. The project is sited in the Totara Valley, a small rural community approximately 70km from the Massey University, Turitea campus, Palmerston North. The Massey University Centre for Energy Research (MUCER) has a long history of renewable energy research within the Totara Valley community. This project complements these existing schemes and provides a foundation for future research into distributed generation technologies. The project encompasses the following objectives: - to gain practical experience in the design, engineering and implementation of a distributed generation system in rural New Zealand; - to evaluate contemporary micro-hydro technology and compare the performance of this equipment in a theoretical and practical context; - to identify barriers that hinder the widespread adoption of micro-hydro systems in rural New Zealand; - to develop a spreadsheet based life cycle costing tool. The results from this study demonstrate that economic considerations are the fundamental aspect to be considered when assessing the long-term viability of these projects. The viability of micro-hydro projects are primarily determined by four factors: - the volume and head (height) of water available above the turbine site; - the length and therefore the cost of the pipeline required for transporting water to the turbine; - the legal and administrative costs involved in obtaining a resource consent to maintain access to the water resources; - the prices received and paid for electricity. Considerable charges were payable to the local authority to secure and maintain the right to harness the water resources at this site. This cost contributed considerable risk to the project and creates a significant barrier to establishing similar systems at other sites. The reduction of resource consent charges to levels that fairly reflect the negligible environmental impacts of these projects would encourage the adoption of this technology and deliver benefits to rural New Zealand communities.
263

Totara Valley micro-hydro development : a thesis presented in partial fulfillment of the requirements for the degree of Master of Applied Science in Renewable Energy Engineering, Massey University, Palmerston North, New Zealand

Donnelly, David Ronald Unknown Date (has links)
This study focuses on the design, construction and operation of a distributed generation system based on micro-hydro technology. The project is sited in the Totara Valley, a small rural community approximately 70km from the Massey University, Turitea campus, Palmerston North. The Massey University Centre for Energy Research (MUCER) has a long history of renewable energy research within the Totara Valley community. This project complements these existing schemes and provides a foundation for future research into distributed generation technologies. The project encompasses the following objectives: - to gain practical experience in the design, engineering and implementation of a distributed generation system in rural New Zealand; - to evaluate contemporary micro-hydro technology and compare the performance of this equipment in a theoretical and practical context; - to identify barriers that hinder the widespread adoption of micro-hydro systems in rural New Zealand; - to develop a spreadsheet based life cycle costing tool. The results from this study demonstrate that economic considerations are the fundamental aspect to be considered when assessing the long-term viability of these projects. The viability of micro-hydro projects are primarily determined by four factors: - the volume and head (height) of water available above the turbine site; - the length and therefore the cost of the pipeline required for transporting water to the turbine; - the legal and administrative costs involved in obtaining a resource consent to maintain access to the water resources; - the prices received and paid for electricity. Considerable charges were payable to the local authority to secure and maintain the right to harness the water resources at this site. This cost contributed considerable risk to the project and creates a significant barrier to establishing similar systems at other sites. The reduction of resource consent charges to levels that fairly reflect the negligible environmental impacts of these projects would encourage the adoption of this technology and deliver benefits to rural New Zealand communities.
264

Totara Valley micro-hydro development : a thesis presented in partial fulfillment of the requirements for the degree of Master of Applied Science in Renewable Energy Engineering, Massey University, Palmerston North, New Zealand

Donnelly, David Ronald Unknown Date (has links)
This study focuses on the design, construction and operation of a distributed generation system based on micro-hydro technology. The project is sited in the Totara Valley, a small rural community approximately 70km from the Massey University, Turitea campus, Palmerston North. The Massey University Centre for Energy Research (MUCER) has a long history of renewable energy research within the Totara Valley community. This project complements these existing schemes and provides a foundation for future research into distributed generation technologies. The project encompasses the following objectives: - to gain practical experience in the design, engineering and implementation of a distributed generation system in rural New Zealand; - to evaluate contemporary micro-hydro technology and compare the performance of this equipment in a theoretical and practical context; - to identify barriers that hinder the widespread adoption of micro-hydro systems in rural New Zealand; - to develop a spreadsheet based life cycle costing tool. The results from this study demonstrate that economic considerations are the fundamental aspect to be considered when assessing the long-term viability of these projects. The viability of micro-hydro projects are primarily determined by four factors: - the volume and head (height) of water available above the turbine site; - the length and therefore the cost of the pipeline required for transporting water to the turbine; - the legal and administrative costs involved in obtaining a resource consent to maintain access to the water resources; - the prices received and paid for electricity. Considerable charges were payable to the local authority to secure and maintain the right to harness the water resources at this site. This cost contributed considerable risk to the project and creates a significant barrier to establishing similar systems at other sites. The reduction of resource consent charges to levels that fairly reflect the negligible environmental impacts of these projects would encourage the adoption of this technology and deliver benefits to rural New Zealand communities.
265

Totara Valley micro-hydro development : a thesis presented in partial fulfillment of the requirements for the degree of Master of Applied Science in Renewable Energy Engineering, Massey University, Palmerston North, New Zealand

Donnelly, David Ronald Unknown Date (has links)
This study focuses on the design, construction and operation of a distributed generation system based on micro-hydro technology. The project is sited in the Totara Valley, a small rural community approximately 70km from the Massey University, Turitea campus, Palmerston North. The Massey University Centre for Energy Research (MUCER) has a long history of renewable energy research within the Totara Valley community. This project complements these existing schemes and provides a foundation for future research into distributed generation technologies. The project encompasses the following objectives: - to gain practical experience in the design, engineering and implementation of a distributed generation system in rural New Zealand; - to evaluate contemporary micro-hydro technology and compare the performance of this equipment in a theoretical and practical context; - to identify barriers that hinder the widespread adoption of micro-hydro systems in rural New Zealand; - to develop a spreadsheet based life cycle costing tool. The results from this study demonstrate that economic considerations are the fundamental aspect to be considered when assessing the long-term viability of these projects. The viability of micro-hydro projects are primarily determined by four factors: - the volume and head (height) of water available above the turbine site; - the length and therefore the cost of the pipeline required for transporting water to the turbine; - the legal and administrative costs involved in obtaining a resource consent to maintain access to the water resources; - the prices received and paid for electricity. Considerable charges were payable to the local authority to secure and maintain the right to harness the water resources at this site. This cost contributed considerable risk to the project and creates a significant barrier to establishing similar systems at other sites. The reduction of resource consent charges to levels that fairly reflect the negligible environmental impacts of these projects would encourage the adoption of this technology and deliver benefits to rural New Zealand communities.
266

Control Strategies for the Next Generation Microgrids

Ali, Mehrizi-Sani 06 December 2012 (has links)
In the context of the envisioned electric power delivery system of the future, the smart grid, this dissertation focuses on control and management strategies for integration of distributed energy resources in the power system. This work conceptualizes a hierarchical framework for the control of microgrids---the building blocks of the smart grid---and develops the notion of potential functions for the secondary control for devising intermediate set points to ensure feasibility of operation of the system. A scalar potential function is defined for each controllable unit of the microgrid such that its minimization corresponds to achieving the control goal. The set points are dynamically updated using communication within the microgrid. This strategy is generalized to (i) include both local and system-wide constraints and (ii) allow a distributed implementation. This dissertation also proposes and evaluates a simple yet elaborate distributed strategy to mitigate the transients of controllable devices of the microgrid using local measurements. This strategy is based on response monitoring and is augmented to the existing controller of a power system device. This strategy can be implemented based on either set point automatic adjustment (SPAA) or set point automatic adjustment with correction enabled (SPAACE) methods. SPAA takes advantage of an approximate model of the system to calculate intermediate set points such that the response to each one is acceptable. SPAACE treats the device as a generic system and monitors its response and modulates its set point to achieve the desired trajectory. SPAACE bases its decisions on the trend of variations of the response and accounts for inaccuracies and unmodeled dynamics. Case studies using the PSCAD/EMTDC software environment and MATLAB programming environment are presented to demonstrate the application and effectiveness of the proposed strategies in different scenarios.
267

Control Strategies for the Next Generation Microgrids

Ali, Mehrizi-Sani 06 December 2012 (has links)
In the context of the envisioned electric power delivery system of the future, the smart grid, this dissertation focuses on control and management strategies for integration of distributed energy resources in the power system. This work conceptualizes a hierarchical framework for the control of microgrids---the building blocks of the smart grid---and develops the notion of potential functions for the secondary control for devising intermediate set points to ensure feasibility of operation of the system. A scalar potential function is defined for each controllable unit of the microgrid such that its minimization corresponds to achieving the control goal. The set points are dynamically updated using communication within the microgrid. This strategy is generalized to (i) include both local and system-wide constraints and (ii) allow a distributed implementation. This dissertation also proposes and evaluates a simple yet elaborate distributed strategy to mitigate the transients of controllable devices of the microgrid using local measurements. This strategy is based on response monitoring and is augmented to the existing controller of a power system device. This strategy can be implemented based on either set point automatic adjustment (SPAA) or set point automatic adjustment with correction enabled (SPAACE) methods. SPAA takes advantage of an approximate model of the system to calculate intermediate set points such that the response to each one is acceptable. SPAACE treats the device as a generic system and monitors its response and modulates its set point to achieve the desired trajectory. SPAACE bases its decisions on the trend of variations of the response and accounts for inaccuracies and unmodeled dynamics. Case studies using the PSCAD/EMTDC software environment and MATLAB programming environment are presented to demonstrate the application and effectiveness of the proposed strategies in different scenarios.
268

On Techno-economic Evaluation of Wind-based DG

Albadi, Mohammed 21 January 2010 (has links)
The growing interest in small-scale electricity generation located near customers, known as Distributed Generation (DG), is driven primarily by emerging technologies, environmental regulations and concerns, electricity market restructuring, and growing customer demand for increased quality and reliability of the electricity supply. Wind turbines are one of the renewable DG technologies that have become an important source of electricity in many parts of the world. Wind power can be used in many places to provide a viable solution to rising demand, energy security and independence, and climate change mitigation. This research aims broadly at facilitating the integration of wind-based DG without jeopardizing the system’s economics and reliability. To achieve this goal, the thesis tackles wind power from three perspectives: those of the policy maker, the investor, and the system operator. Generally, the economic viability of a project is determined within the framework of relevant policies. Therefore, these policies influence the decisions of potential investors in wind power. From this perspective, chapters 3 and 4 investigate the influence of policies on the economic viability of wind-based DG projects. In chapter 3, the role of Ontario’s taxation and incentive policies in the economic viability of wind-based DG projects is investigated. In this study, the effects of provincial income taxes, capital cost allowances, property taxes, and relevant federal incentives are considered. Net Present Value (NPV) and Internal Rate of Return (IRR) for different scenarios are used to assess the project’s viability under the Ontario Standard Offer Program (SOP) for wind power. In chapter 4, the thesis proposes the use of wind power as a source of electricity in a new city being developed in the Duqm area of Oman, where no policies supporting renewable energy exist. The study shows that the cost of electricity produced by wind turbines is higher than that of the existing generation system, due to the subsidized prices of domestically available natural gas. However, given high international natural gas prices, the country’s long-term Liquefied Natural Gas (LNG) export obligations, and the expansion of natural gas-based industries, investments in wind power in Duqm can be justified. A feed-in tariff and capital cost allowance policies are recommended to facilitate investments in this sector. From a wind-based DG investor’s perspective, the optimal selection of wind turbines can make wind power more economical, as illustrated in chapters 5 and 6. In chapter 5, the thesis presents a new generic model for Capacity Factor (CF) estimation using wind speed characteristics at any site and the power performance curve parameters of any pitch-regulated wind turbine. Compared to the existing model, the proposed formulation is simpler and results in more accurate CF estimation. CF models can be used by wind-based DG investors for optimal turbine-site matching applications. However, in chapter 6, the thesis demonstrates that using CF models as the sole basis for turbine-site matching applications tends to produce results that are biased towards higher towers but do not include the associated costs. Therefore, a novel formulation for the turbine-site matching problem, based on a modified CF formulation that does include turbine tower height, is introduced in chapter 6. The proposed universal Turbine-Site Matching Index (TSMI) also includes the effects of turbine rated power and tower height on the initial capital cost of wind turbines. Chapter 7 tackles wind power from a power system operator’s perspective. Despite wind power benefits, the effects of its intermittent nature on power systems need to be carefully examined as penetration levels increase. In this chapter, the thesis investigates the effects of different temporal wind profiles on the scheduling costs of thermal generation units. Two profiles are considered: synoptic-dominated and diurnal-dominated variations of aggregated wind power. To simulate wind profile impacts, a linear mixed-integer unit commitment problem is formulated in a GAMS environment. The uncertainty associated with wind power is represented using a chance constrained formulation. The simulation results illustrate the significant impacts of different wind profiles on fuel saving benefits, startup costs, and wind power curtailments. In addition, the results demonstrate the importance of the wide geographical dispersion of wind power production facilities to minimize the impacts of network constraints on the value of the harvested wind energy and the amount of curtailed energy.
269

On Techno-economic Evaluation of Wind-based DG

Albadi, Mohammed 21 January 2010 (has links)
The growing interest in small-scale electricity generation located near customers, known as Distributed Generation (DG), is driven primarily by emerging technologies, environmental regulations and concerns, electricity market restructuring, and growing customer demand for increased quality and reliability of the electricity supply. Wind turbines are one of the renewable DG technologies that have become an important source of electricity in many parts of the world. Wind power can be used in many places to provide a viable solution to rising demand, energy security and independence, and climate change mitigation. This research aims broadly at facilitating the integration of wind-based DG without jeopardizing the system’s economics and reliability. To achieve this goal, the thesis tackles wind power from three perspectives: those of the policy maker, the investor, and the system operator. Generally, the economic viability of a project is determined within the framework of relevant policies. Therefore, these policies influence the decisions of potential investors in wind power. From this perspective, chapters 3 and 4 investigate the influence of policies on the economic viability of wind-based DG projects. In chapter 3, the role of Ontario’s taxation and incentive policies in the economic viability of wind-based DG projects is investigated. In this study, the effects of provincial income taxes, capital cost allowances, property taxes, and relevant federal incentives are considered. Net Present Value (NPV) and Internal Rate of Return (IRR) for different scenarios are used to assess the project’s viability under the Ontario Standard Offer Program (SOP) for wind power. In chapter 4, the thesis proposes the use of wind power as a source of electricity in a new city being developed in the Duqm area of Oman, where no policies supporting renewable energy exist. The study shows that the cost of electricity produced by wind turbines is higher than that of the existing generation system, due to the subsidized prices of domestically available natural gas. However, given high international natural gas prices, the country’s long-term Liquefied Natural Gas (LNG) export obligations, and the expansion of natural gas-based industries, investments in wind power in Duqm can be justified. A feed-in tariff and capital cost allowance policies are recommended to facilitate investments in this sector. From a wind-based DG investor’s perspective, the optimal selection of wind turbines can make wind power more economical, as illustrated in chapters 5 and 6. In chapter 5, the thesis presents a new generic model for Capacity Factor (CF) estimation using wind speed characteristics at any site and the power performance curve parameters of any pitch-regulated wind turbine. Compared to the existing model, the proposed formulation is simpler and results in more accurate CF estimation. CF models can be used by wind-based DG investors for optimal turbine-site matching applications. However, in chapter 6, the thesis demonstrates that using CF models as the sole basis for turbine-site matching applications tends to produce results that are biased towards higher towers but do not include the associated costs. Therefore, a novel formulation for the turbine-site matching problem, based on a modified CF formulation that does include turbine tower height, is introduced in chapter 6. The proposed universal Turbine-Site Matching Index (TSMI) also includes the effects of turbine rated power and tower height on the initial capital cost of wind turbines. Chapter 7 tackles wind power from a power system operator’s perspective. Despite wind power benefits, the effects of its intermittent nature on power systems need to be carefully examined as penetration levels increase. In this chapter, the thesis investigates the effects of different temporal wind profiles on the scheduling costs of thermal generation units. Two profiles are considered: synoptic-dominated and diurnal-dominated variations of aggregated wind power. To simulate wind profile impacts, a linear mixed-integer unit commitment problem is formulated in a GAMS environment. The uncertainty associated with wind power is represented using a chance constrained formulation. The simulation results illustrate the significant impacts of different wind profiles on fuel saving benefits, startup costs, and wind power curtailments. In addition, the results demonstrate the importance of the wide geographical dispersion of wind power production facilities to minimize the impacts of network constraints on the value of the harvested wind energy and the amount of curtailed energy.
270

Small Area Power Plant Optimal Planning with Distributed Generations and Green House Gas Reduction

Lin, Chang-ming 27 June 2011 (has links)
In recent years, with the energy shortage, the use of renewable energy is inevitable. With CO2 the most important greenhouse gas causing global warming as well as the increase of population, renewable energy is one way to save energy and reduce carbon emissions. The traditional capacity investment for serving the load in distribution systems usually considered the addition of new substations or expansion of the existing substation and associated new feeder requirement. Nowadays, there are a lots of distributed generations (DG¡¦s) to be chosen. Factors of the choice taken into account will include lower pollution, higher efficiency, higher return rate for construction of distributed power generation systems. This thesis assumes that the distributed generation can be invested for long-term power plant planning. The planning of DG would be investigated from the perspectives of the independent investors. The modified Particle Swarm Optimization is proposed to determine the optimal sizing and sit of DG¡¦s addition in distribution systems with the constrains of CO2 limitation and addition of distributed generation to maximize profits. This thesis deals with discrete programming problem of optimal power flow, which includes continuous and discrete types of variables. The continuous variables are the generating unit real power output and the bus voltage magnitudes, the discrete variables are the shunt capacitor banks and sit problems. The Miaoli-Houlong system of Taiwan power will be used in this thesis for the verification of the feasibility of the proposed method.

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