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The value of electrical energy storage : a comparison between commercial and system level benefitsDunbar, Anna January 2016 (has links)
There is a drive to transform the electricity industry in the UK from one based largely on fossil fuels to one based on low or zero carbon sources. The challenge of this transition, enabling a secure and sustainable electricity industry at an acceptable cost to consumers, has been dubbed the Energy Trilemma. Grid-connected electrical energy storage presents a potential solution to this challenge. However, the benefits of storage are split across different sectors of the electricity industry and there are a number of regulatory barriers preventing access to revenue streams. One accessible revenue stream is energy trading or price arbitrage. In current market conditions, arbitrage cannot provide sufficient revenue for electricity storage to cover its capital costs; however, some studies have suggested that with increased penetration of intermittent renewable power, electricity price volatility will increase enabling storage to become commercially viable through price arbitrage alone. This thesis examines the hypothesis that: Increased wind penetration leads to increased commercial opportunities for energy storage through price arbitrage. A linear programme is used to define the optimum operating strategy for a storage device, subject to the constraints of maximum storage capacity, charging and discharging rates, conversion efficiency and self-discharge. Initially, historic electricity prices from the British electricity market are used to investigate the value of storage with a low penetration of intermittent wind power. The results show that revenue is dependent on storage characteristics, with the performance of different technologies varying substantially. Furthermore, revenue is highly dependent on changes in market structure and fuel price variations from one year to the next. The thesis describes the development of a fundamental electricity price model based on the stacked merit order dispatch of thermal generation bidding to produce electricity in a competitive market centred around marginal generation costs. For peaking plant, an exponential uplift in price is applied to represent scarcity of supply. The implications of increasing wind power output are examined using projections of the location and capacity of future wind farms and spatially distributed hind cast wind speed data generated from a mesoscale atmospheric model. The analysis highlights that despite increased value being placed on storage in an energy system with a high penetration of wind power, opportunities for arbitrage are, in fact, reduced. This is a result of an oversupply of electricity on windy days suppressing peak electricity prices and reducing the daily price spread, which arbitrage exploits.
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Bacterial Response to Crude Oil Spillage in a Salt MarshHerwig, Russell Paul 01 January 1978 (has links)
No description available.
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Micro Hydro a Feasibility Study and Design ImplementationStrom, Davin A 01 December 2016 (has links)
Hydro power can be defined as converting the energy of flowing water into useful mechanical power by a turbine or water wheel. A micro hydro system typically has an electrical generation capacity of less than 100 kilo watts. These systems are usually constructed to supply power to individuals or groups of individuals who are independent of the power supply grid. The scope of this project is to outline the principles of micro hydro and to document the design process of a micro hydro site. This will include the measurements, calculations, and methods performed in a feasibility study for a potential site. The desired outcome of the project is to develop a viable solution to gain energy independence at a remote site owned by the author.
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Distributed Generation: Issues Concerning a Changing Power Grid ParadigmTherien, Scott G.M. 01 June 2010 (has links)
Distributed generation is becoming increasingly prevalent on power grids around the world. Conventional designs and grid operations are not always sufficient for handling the implementation of distributed generation units; the new generation may result in undesirable operating conditions, or system failure. This paper investigates the primary issues involved with the implementation of distributed generation and maintaining the integrity of the power grid. The issues addressed include power flow, system protections, voltage regulation, intermittency, harmonics, and islanding. A case study is also presented to illustrate how these issues can be addressed when designing distributed generation installation on an existent distribution system. The case study design is performed on the campus distribution system of California Polytechnic State University, San Luis Obispo, with the design goal of implementing renewable energy sources to make the campus a net zero energy consumer.
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Modeling and Analysis of a Four-Switch Buck-Boost Dynamic CapacitorPlasencia, Oscar 01 December 2011 (has links)
Modern electric power utilities are facing a variety of challenges introduced by the increasing complexity of their operation, structure, and consumer loads. One such challenge has been to supply the ever growing demand for reactive power which is essential for grid support. For this reason dynamic VAR technologies are becoming much more important to modern day power systems. A recent dynamic VAR technology known as the Dynamic Capacitor offers full quadrant capacitive VAR control through the combination of AC/AC buck and boost cells. This paper introduces a new topology deemed the “Four-Switch Buck-Boost Dynamic Capacitor” which promises to combine the performance of the AC/AC buck and boost cells into a single power electronic device. This is done in an effort to reduce the required component count and thus reduce the overall device footprint and implementation cost of the Dynamic Capacitor technology. Derivations and analysis will detail the workings of the Four-Switch Buck-Boost Dynamic Capacitor, while simulations in LTSpice and Matlab Simulink will demonstrate the functionality and performance of the proposed topology. The results of this thesis prove the Four-Switch Buck-Boost Dynamic Capacitor to be a feasible shunt reactive compensating device.
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Localized Surface Plasmon Resonance with the use of Silver and Titanium Oxide NanostructuresChin, Charles Wei-Shing 01 August 2011 (has links)
Light scattering and surface Plasmon calculations were done on a variety of novel geometries using the DDSCAT software package, which simulates the scattering of objects using the discrete dipole approximation method. Calculations were done on core shell nanoparticles consisting of a silver shell and a TiO2 core in order to determine changes in the extinction spectrum and the near field patterns. Several geometries were tested, including spheres, cylinders, and hexagons, each of varying size and number. It was determined that when geometries were coupled together, there was significant near field enhancement where the geometries were in contact. This enhancement along with the increase in extinction in the visible region of the light spectrum makes these nanoparticles idea for solar cell technology, where they would increase efficiency.
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Unit Commitment Methods to Accommodate High Levels of Wind GenerationMelhorn, Alexander Charles 01 August 2011 (has links)
The United State’s renewable portfolio standards call for a large increase of renewable energy and improved conservation efforts over today’s current system. Wind will play a ma jor role in meeting the renewable portfolio standards. As a result, the amount of wind capacity and generation has been growing exponentially over the past 10 to 15 years. The proposed unit commitment method integrates wind energy into a scheduable resource while keeping the formulation simple using mixed integer programming. A reserve constraint is developed and added to unit commitment giving the forecasted wind energy an effective cost. The reserve constraint can be scaled based on the needs of the system: cost, reliability, or the penetration of wind energy. The results show that approximately 24% of the load can be met in the given test system, while keeping a constant reliability before and after wind is introduced. This amount of wind will alone meet many of the renewable portfolio standards in the United States.
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INVESTIGATION OF PROTECTION ISSUES AND METHOD FOR THE DISTRIBUTION SYSTEM WITH DISTRIBUTED GENERATIONSXu, Ke 01 January 2014 (has links)
Because DGs are introduced into distribution systems, the coordination of fuses and reclosers doesn’t work well. It means the original protection schemes are not available for the distribution systems with DGs. This thesis paper presents the study on the impacts of DGs on the fault current and voltage in the distribution system by the simulation of a model distribution system. After we study the impacts of DG on distribution systems, there is an introduction of current several current protection schemes and fault locations methods. At last, an adaptive protection scheme with a more efficient fault location method for the distribution systems is discussed in this thesis paper.
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Modelling, simulation and control of photovoltaic converter systemsGow, John A. January 1998 (has links)
The thesis follows the development of an advanced solar photovoltaic power conversion system from first principles. It is divided into five parts. The first section shows the development of a circuit-based simulation model of a photovoltaic (PV) cell within the 'SABER' simulator environment. Although simulation models for photovoltaic cells are available these are usually application specific, mathematically intensive and not suited to the development of power electronics. The model derived within the thesis is a circuit-based model that makes use of a series of current/voltage data sets taken from an actual cell in order to define the relationships between the cell double-exponential model parameters and the environmental parameters of temperature and irradiance. Resulting expressions define a 'black box' model, and the power electronics designer may simply specify values of temperature and irradiance to the model, and the simulated electrical connections to the cell provide the appropriate I/V characteristic. The second section deals with the development of a simulation model of an advanced PVaware DC-DC converter system. This differs from the conventional in that by using an embedded maximum power tracking system within a conventional linear feedback control arrangement it addresses the problem of loads which may not require the level of power available at the maximum power point, but is also able to drive loads which consistently require a maximum power feed such as a grid-coupled inverter. The third section details a low-power implementation of the above system in hardware. This shows the viability of the new, fast embedded maximum power tracking system and also the advantages of the system in terms of speed and response time over conventional systems. The fourth section builds upon the simulation model developed in the second section by adding an inverter allowing AC loads (including a utility) to be driven. The complete system is simulated and a set of results obtained showing that the system is a usable one. The final section describes the construction and analysis of a complete system in hardware (c. 500W) and identifies the suitability of the system to appropriate applications.
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Distribution system operation and planning in the presence of distributed generation technologyJones, Gavin Wesley, January 2007 (has links) (PDF)
Thesis (M.S.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed November 16, 2007) Includes bibliographical references (p. 71-74).
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