Dissertations / Theses on the topic 'Grid impact'
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1
Azcarate, Lara Francisco Javier. "Dualmode transportation - impact on the electric grid." Texas A&M University, 2007. http://hdl.handle.net/1969.1/85823.
Full textAbstract:
Continual increase in transport demand and uneven road capacity results in chaotic
traffic congestion, brings with it high levels of air pollution, an elevated number of
accidents, and an insatiable demand for oil to satisfy the motorized vehicles on roads.
The dualmode transportation system is a transformational solution to address all of these
problems simultaneously. This project will quantify the amount of energy needed to
electrify a portion of the actual ground transportation (personal vehicle and freight) in a
specific electric region grid and analyze the impact that it represents. A model that gives
a close approximation of the electric energy demand that would be generated by
converting existing traffic data into electricity demand was developed. This model
allows for sensitivity testing of all conversion factors, data variation and variations in the
different types of propulsion technology that may be used in the new system. Results
show that inclusion of the new transportation system into the electric grid of Texas will
not require significantly more energy than the current available resource.
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Odnegård, Joakim. "Fault Impact Mitigation in Grid Connected Converters." Thesis, KTH, Elektrisk energiomvandling, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-107494.
Full textAbstract:
The present thesis deals with fault impact mitigation in grid connected converters used for High Voltage Direct Current transmission. Certain critical fault cases require additional obstructing protection actions to ease the impact on the converter valves. DC sided faults drives high fault currents through the converters. Single phase to ground faults at the converter AC bus results in overvoltages across the converter valve arms. The phenomenon of these faults are described both for symmetric and asymmetric configurations. Different available solutions are explained and evaluated. Simulations in PSCAD/EMTDC show the impact of the protection measures. A three phase short circuit introduced on the tertiary winding of the transformer is an effective temporary measure against the destructive fault cases. It is shown in this report that a tertiary shortcircuit will greatly reduce the overvoltages after converter bus faults and redirect a large part of the fault currents after DC faults. With the lower voltage on the tertiary winding, it is a suitable connection point for short circuit devices.
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Engdahl, Annelie. "How grid connected solar cells impact on the low voltage grid of Duckarp." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-33952.
Full textAbstract:
To limit the ongoing climate change and to meet the UN target for an increased temperature of maximum 2 degrees, governments worldwide strive for sustainable and fossil free power generation. Hence, Photovoltaic Solar Cells (PVs) are of great interest. The potential from sun is infinite; the annual solar radiation corresponds to 6.000 times the human energy demand (IEA, 2011). In Sweden, the power generation from sun is 0.6 ‰ (Swedenergy, 2016). It is a very small, but strongly growing, share. In the municipality of Kristianstad, south of Sweden, the vision of power generation from sun is clear: by 2040, 5 % of the electricity consumption in the area is to come from PVs (Kristianstad kommun, 2016). Along with an increased interest from subscribers, more grid connected PVs are to be expected. An increased share of grid-connected PVs, influences the power grid. The power quality must comply with legal requirements and maintain a certain voltage. This might be a problem in rural power grids where the distances are far; the grid is getting weaker and the voltage deviation grows. Never the less, the law requires the concession holder to compensate the subscriber in relation to the decreased losses in the grid. With power generation closer to the subscriber, the distances are shorter and the grid losses is decreased. Mellersta Skånes Kraft (MSK) is a power distribution company located in Scania, south of Sweden. In the feeding 6 kV grid, a major part of the conductors are over-head lines, meaning a lot of interruptions caused by stormy weather and fallen trees. Hence, MSK is planning for isolated conductors to decrease the number of interruptions. At present, MSK have a few, sporadically placed, grid connected PVs and the power generation of today, regarding power quality, is not a problem. However, MSK sees an increased interest in PVs and more power generation the next few years are to be expected. The question is, how several grid-connected PVs will impact the power grid. In this dissertation, the rural low voltage grid of Duckarp, Kristianstad municipality, has been studied. The grid is connected to the very last transformer in a radial grid. Two cases have been modulated: one with existing PVs of today, and one with PVs at all subscribers connected to the transformer T-640, Duckarp. As the feeding 6 kV grid is to be rebuilt, the study included the choice of cable cross section area in the 6 kV grid as well. The study included grid strength, voltage deviation, load in cables and transformer, and grid losses including compensation to subscriber. The study shows, that with present PVs and with the condition that a tap changing transformer is used, the grid is strong and capable of keeping the voltage required. Due to voltage deviation, more grid connected PVs make the grid weaker and require higher cable cross section areas on the feeding 6 kV grid. The load is not a problem, but still there is a risk of a high proportion of harmonics in the neutral and in the transformer. This, due to the low voltage grid being located in the weakest part of the grid. The reduced losses, due to local power generation, corresponds to a compensation to subscriber of 0.02 SEK/kWh. Building strong power grids is expensive and alternative solutions, so-called smart grids, are of interest; Line Voltage Regulator (LVR), reactive power generation in the inverter, battery storage, or load regulations to mention some. But when there is an ongoing reconstruction of the grid, as in the case studied, it is appropriate to build a strong power grid to meet a future expansion of grid-connected PVs.
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Jimenez, Arismendi Eduardo A. "The impact of grid geometry on displacement calculations." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1102.
Full textAbstract:
Reservoir simulation models are becoming increasingly sophisticated in tandem with the rapid development of geological modeling methods. Widely used commercial simulators usually model flow through heavily faulted and structurally complex geometries with the flexibility provided by corner-point geometry. However, the nonorthogonality component present within these frameworks may compromise the solution accuracy of the model and the subsequent operational decisions involved.
We propose a systematic methodology to evaluate the impact of complex gridding introducing a new streamline formulation for corner-point geometry. Based on a new time-like variable, the new formulation provides a significantly simpler and more robust development to handle the complexity in structurally demanding and faulted systems. It retains the simplicity and speed of streamline-based flow models and provides an efficient way to visualize nonorthogonal effects.
Applied to various geometries showing challenging features of geology and flow, the displacement fronts obtained from streamline-derived analytic calculation identified the discrepancies characteristic between known solutions and results from two widely used commercial simulators.
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Felix, Isbi. "Dynamic analysis of the impact of grid connection of "La Higuera" hydropower plant to the transmission grid." Thesis, KTH, Elektriska energisystem, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-118929.
Full textAbstract:
Studies regarding the development of a new hydropower plant exploiting the water resources offered by the upper Tinguiririca river, located about 150 km south-east of the capital Santiago in Chile, has been done by Pacific Hydro Ltd from Australia and Lahmeyer International from Germany. These studies have resulted in proposals to construct two Hydropower Stations, �La Higuera� and �Confluencia�. Both hydropower stations will have a total installed capacity of 300 MW. When setting up a new hydropower plant, it is important to foresee how the hydropower plant would affect the existing transmission grid in different situations during operation as well as how events in the grid may affect the La Higuera and/or Confluencia hydropower stations. In this report three kind of analysis are highlighted, which are static analysis, large signal stability and rotor angle stability. To perform these analyses a simulation tool named DigSilent is used. DigSilent is used to perform these analyses in a simulated network of the studied transmission system. These two hydropower stations as shown in the results will improve the existing transmission system by enhancing the stability margins in the presence of a fault. When performing the simulation of the existing transmission system with the newly installed hydropower plant we could see that it had a poor damping after a disturbance; this might be due to the large distance between production plants and the existing loads. This phenomenon can be alleviated if a power system stabilizer (PSS) is integrated in the hydropower plant. The final conclusion is that the integration of the two hydropower plants will improve the existing transmission system in Chile.
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Wagner, Thibaut. "Impact of remote controlled switches on distribution grid recovering processeas." Thesis, KTH, Elektriska energisystem, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-119572.
Full textAbstract:
Remote controlled switches (RCS) are used to enhance the recovering process of distribution grids. Commonly installed on MV-lines to sectionize feeders, they are a cheap and efficient way to improve the B criterion as well as the incident localisation speed. This document explains and models the impact of Remote controlled equipment on B criterion and reactivity depending on grid structure and organisation (II and III). This model is then used to define an optimal remote controlled switcher number per feeder on each specific area (V). It leads to two main results: French territory is not homogeneously equipped and a lot of areas need a strong RCS policy. RCS efficiency on distributor performance is also proved to be high even for well-equipped areas.
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Sambasivan, Shiv Kumar. "A sharp interface Cartesian grid hydrocode." Diss., University of Iowa, 2010. https://ir.uiowa.edu/etd/593.
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Dynamic response of materials to high-speed and high-intensity loading conditions is important in several applications including high-speed flows with droplets, bubbles and particles, and hyper-velocity impact and penetration processes. In such high-pressure physics problems, simulations encounter challenges associated with the treatment of material interfaces, particularly when strong nonlinear waves like shock and detonation waves impinge upon them. To simulate such complicated interfacial dynamics problems, a fixed Cartesian grid approach in conjunction with levelset interface tracking is attractive. In this regard, a sharp interface Cartesian grid-based, Ghost Fluid Method (GFM) is developed for resolving embedded fluid, elasto-plastic solid and rigid (solid) objects in hyper-velocity impact and high-intensity shock loaded environment. The embedded boundaries are tracked and represented by virtue of the level set interface tracking technique. The evolving multi-material interface and the flow are coupled by meticulously enforcing the boundary conditions and jump relations at the interface. In addition, a tree-based Local Mesh Refinement scheme is employed to efficiently resolve the desired physics. The framework developed is generic and is applicable to interfaces separating a wide range of materials and for a broad spectrum of speeds of interaction (O(km/s)). The wide repertoire of problems solved in this work demonstrates the flexibility, stability and robustness of the method in accurately capturing the dynamics of the embedded interface. Shocks interacting with large ensembles of particles are also computed.
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Lorenzo, Kevin. "Harmonics propagation and impact of Electric Vehicles on the electrical grid." Thesis, KTH, Elektrisk energiomvandling, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-153678.
Full textAbstract:
This thesis addresses the issues of (inter)harmonics propagation on electrical grids. More specifically it concerns two different kinds of studies. The first one is the harmonic impact of the integration of new technologies such as Electric Vehicle charging parks which generate harmonic voltages. The second one is the propagation on these grids of communication signals such as the pricing signal. These two kinds of voltages behave a priori the same way since they are superimposed to the fundamental feeding voltage, with a higher frequency. However, their main structural difference is that, while harmonic voltages generated by electric cars are unwanted on electrical grid, the pricing signal is intended at certain points of the grid. For the first kind of studies, concerning harmonics generated by Electric Vehicles, the aim of this project was to determine the problems that may appear on electrical grids when electric car parks are connected thereto. To do so, laboratory measurements on several Electric Vehicle models, separately or simultaneously, were performed. From their results, different models of EVs have been drawn up enabling to perform simulations on an existing car park. Some measurements were then carried out on this car park in order to conclude on its impact on the Power Quality of the grid. The second study is about the pricing signal propagation. It focuses on different ways of modeling grid components, especially loads, in simulation tools at the specific frequency of this signal. For Medium Voltage grids, several load models can be found in the literature and are compared in this report. For Low Voltage grids, a model based on the results of recent measurements is suggested in the report.
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GUSTAFSSON, EMIL, and FREDRIK NORDSTRÖM. "Impact of electric vehicle charging on thedistribution grid in Uppsala 2030." Thesis, KTH, Energiteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211708.
Full textAbstract:
Planning of distribution grids is based on statistically estimating the maximum load that will occur given a certain range of criteria (location, household types, district / electric heating etc.) Charging of electric vehicles is not one of these criteria. However, given the expected `boom' in sales of Chargeable Electric Vehicles (CEVs), and the lengthy planning process of distribution grids (>10 years) the knowledge gap is becoming a more pressing issue. This research has been conducted to investigate if Vattenfall, a Swedish electric utility company with distribution assets in both Sweden and Germany, needs to take action to react to the expected increase in CEVs in the near term. The study has been conducted with Uppsala Municipality as a showcase and 2030 as the time frame. The findings of this study show that Vattenfall should incorporate CEV usage into distribution planning to avoid overload of power stations in Uppsala by 2030. The ndings shows that 1) we can expect a 'boom' in sales of CEVs in the near future and that 73% of cars in trac in Uppsala may be CEVs by 2030 and 2) that CEV charging is expected to have a signi- cant impact on the distribution grid, with certain power stations in Uppsala seeing a peak load increase of up to 30%. The recommended actions are the following: • Monitor specific areas with a high concentration of cars and low energy consumption per household that already have substations with capacity below the recommended dimensions • Monitor CEV sales to reevaluate current projections on CEV development in Uppsala • Monitor trends of car ownership and evaluate whether this will aect CEV charging behaviour • Reconstruct Velander constants, used for grid planning, to take the CEV load into consideration • Investigate smart charging solutions, to shift the CEV load peak to a different time of the dayDimensionering av distributionsnat baseras pa att statistiskt uppskatta den maximala lasten som kommer att intraa pa natet, givet olika faktorer (geograskt lage, hushallstyp, fjarrvarme / elvarme etc.). Laddning av elbilar ar inte en av de faktorer som man tar hansyn till. Givet en vantat kraftig okning av laddningsbara bilar, samt den langa planeringshorisonten for distributionsn at (>10 ar), blir dock fragan hur elbilar kommer att paverka elnatet valdigt aktuell. Denna studie har bedrivits for att avgora hur Vattenfall, ett statligt, svenskt elbolag med distributionsnat i Sverige och Tyskland, behover agera for att anpassa sig till den forvantade okningen av elbilar. Den har studien har genomforts som en fallstudie pa Uppsala Kommun med ar 2030 som tidsram. Resultaten fran studien visar att Vattenfall bor ta hansyn till laddning av elbilar vid dimensionering av distributionsnat for att undvika overbelastning pa natstationer i Uppsala ar 2030. Resultaten visar dels att 1) man kan forvanta sig en kraftig okning av forsaljning av laddningsbara fordon inom en snar framtid och uppemot 73 % av alla bilar i trak i Uppsala kommer att vara laddningsbaraar 2030 samt att 2) laddningsbara fordon kommer att ha en signikant paverkan pa distributionsnatet med okningar pa upp till 30 % av maxlasten for vissa natstationer. Foljande atgarder rekommenderas saledes: • Overvaka specika omraden med hog biltathet och lag energianvandning per hushall som ar anslutna till natstationer som ar underdimensionerade • Folj utvecklingen av forsaljning av laddbara fordon for att omvardera genom forda projektioner over laddningsbara bilar i Uppsala • Overvaka trender inom bilagande och utvardera hur detta paverkar laddningsbeteende • Gor om Velanderkonstanter sa att de tar hansyn till lasten fran laddbara fordon vid planering av elnat • Utvardera smarta laddningslosningar for att ytta last fran elbilsladdning till en annan tidpunkt pa dygnet
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Mattaparthi, Sai Venkata Akshay. "The Impact of Hexagonal grid on thePrincipal Component of Natural Images." Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-17236.
Full textAbstract:
The visual processing in the real world is different from the digital world. Monkey’s and a human’s visual world is richer and more colourful affording sight of flies, regardless of whether they are immobile or airborne. The study of the evolutionary process of our visual system indicates the existence of variationally spatial arrangement; from densely hexagonal in the fovea to a sparse circular structure in the peripheral retina. Normally we use a rectangular grid for the processing of images. But as per the perspective of the human eyes, the new approach is to change the grid from rectangular to hexagonal. Applying hexagonal grid in image processing is very advantageous and easy for mimicking human visual system. The main advantages for using the hexagonal structure in image processing is its resemblance to the arrangement of photoreceptors in the human eyes. The visual processing in the real world is different from the digital world. Monkey’s and a human’s visual world is richer and more colourful affording sight of flies, regardless of whether they are immobile or airborne. The study of the evolutionary process of our visual system indicates the existence of variationally spatial arrangement; from densely hexagonal in the fovea to a sparse circular structure in the peripheral retina. Normally we use a rectangular grid for the processing of images. But as per the perspective of the human eyes, the new approach is to change the grid from rectangular to hexagonal. Applying hexagonal grid in image processing is very advantageous and easy for mimicking human visual system. The main advantages for using the hexagonal structure in image processing is its resemblance to the arrangement of photoreceptors in the human eyes.
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Persaud, Shashi. "Impact of wind energy development on utility network behaviour and system operation." Thesis, Queen's University Belfast, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343025.
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Karlsson, Elin. "Charging infrastructure forelectric city buses : An analysis of grid impact and costs." Thesis, KTH, Skolan för elektro- och systemteknik (EES), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192319.
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An increased demand for fossil free transport have led to developments in the area of electric vehicles. Many companies and organizations are carrying out projects where electric city buses are tested in normal operation, and the result suggests that this can be an option with big potential. This thesis is carried out at Scania CV AB. The aim is to investigate the total investment cost for society when electrifying a complete bus system. It focuses on grid connections for the chargers, but battery costs and charger costs are also included. To achieve this, a case study of Stockholm is carried out. In the case study, the bus system of Stockholm is investigated, and from this three different scenarios are created with three different charging strategies. The first scenario includes only charging at the depots, when the bus is parked over the night. The second scenario uses end station charging combined with depot charging during the night. From these strategies, requirements for the batteries and the charging powers are set. The third scenario, on the other hand, starts from a battery available today. From these specifications, a charging strategy that includes end stations charging, depot charging as well as charging at selected bus stations is chosen in order to cover the demands of the bus system. For the three strategies, the possibilities to connect the chargers to the electric grid are investigated using data from the distribution grid owner in Stockholm, Ellevio AB. From this, conclusions regarding the available capacity and required extensions are made, and the costs is investigated. Also, a comparison case study for the small city Mora in Sweden is carried out, and a short discussion regarding possibilities in a larger European city is included. The result shows that is probably most profitable to charge during the day, at end stations and selected bus stations, combined with depot charging. The grid connection cost is a significant part of the total costs, and should not be neglected. On the other hand, the total cost is relatively small, and electrification is considered possible within a short future. Except for the costs included in this thesis, costs related to projecting of the system as well as permitting for the new substations should be included. A deeper analysis of the possibilities to build new substations within the city region need to be carried out, as well as an analysis of the total cost of operation for the electrified system. This should then include the time parameter and the lifetime of the components.En ökad efterfrågan på fossilfri transport har lett till stor utveckling inom elektriska fordon. Många aktörer genomför projekt där elektriska stadsbussar testas i daglig drift, och mycket tyder på att detta är ett alternativ med goda möjligheter. Detta examensarbete skrivs i samarbete med Scania CV AB. Arbetet syftar till att uppskatta totala investeringskostnaden för samhället vid elektrifiering av ett helt bussystem. Fokus ligger på nätanslutning av laddstationerna, men även kostnader för batterier och laddare inkluderas. För att uppnå detta har en fallstudie gjorts över Stockholm, där bussystemet kartlagts och tre scenarion med tre olika strategier för laddning har jämförts. Scenario 1 innefattar endast laddning vid depåerna, medan scenario 2 använder laddning vid ändhållplatserna i kombination med depåladdning. För dessa scenarion ställs krav på batterikapacitet samt laddeffekter. Scenario 3 utgår i stället från batterier som finns tillgängliga idag, och från dessa specifikationer bestäms en laddstrategi som uppfyller bussystemets behov. För dessa tre scenarion har möjligheterna att ansluta laddarna till elnätet utretts med hjälp av elnätsdata från Ellevio AB, som äger distributionsnätet i Stockholm. Från detta kan slutsatser gällande tillgänglig effekt och behov av utbyggnad dras, och kostnaderna uppskattas. Även en jämförande fallstudie för Mora, en mindre ort i Sverige med andra förutsättningar, samt en kort diskussion kring hur förutsättningarna ser ut i en större europeisk stad, har inkluderats. Resultatet visar att det sannolikt är mest lönsamt att välja att ladda under dagen, vid ändstationer och eventuellt vid utvalda mellanliggande stationer, i kombination med laddning vid depåerna. Nätanslutningskostnaden står för en signifikant del av kostnaderna och bör inte försummas, men den totala kostnaden är relativt liten vilket gör att elektrifiering bedöms möjlig inom en snar framtid. Utöver de kostnader som inkluderats i detta arbete behöver kostnader relaterade till projektering och planering av systemet inkluderas, och en djupare analys av möjligheten att bygga nya nätstationer bör genomföras. I detta arbete är heller inte livslängden på komponenterna inräknad, vilket påverkar totala kostnaden för ägande och drift och alltså påverkar lönsamheten.
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Isaac, Nithin. "Economic impact of captive solar technology and an ideal grid penetration level." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/59842.
Full textAbstract:
Since the 2008 energy crisis, the national utility has been under stress to meet the country's electrical demand. Moreover, the costs of building new conventional power stations and the operation and maintenance costs of existing ones are taking a toll on the economy. The utility has hence resorted to hiking electricity tariffs. This combination of rising electricity prices and decreasing costs of photovoltaic (PV) technology have hence led a number of households to cover part of their electricity demand by self-produced captive solar PV technology. Reliable supply of energy is the backbone of a growing economy, hence the integration of captive solar PV technology, and self-generation seems to be growing on the back of an impending energy crisis. Although the integration of cleaner energy sources is good, uncontrolled or over penetration of captive solar technology could become a threat to the utility.Mini Dissertation (MBA)--University of Pretoria, 2017.
nk2017
Gordon Institute of Business Science (GIBS)
MBA
Unrestricted
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Omole, Adedamola. "Voltage Stability Impact of Grid-Tied Photovoltaic Systems Utilizing Dynamic Reactive Power Control." Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3615.
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Photovoltaic (PV) DGs can be optimized to provide reactive power support to the grid,
although this feature is currently rarely utilized as most DG systems are designed to
operate with unity power factor and supply real power only to the grid. In this work, the
voltage stability of a power system embedded with PV DG is examined in the context of
the high reactive power requirement after a voltage sag or fault. A real-time dynamic
multi-function power controller that enables renewable source PV DGs to provide the
reactive power support necessary to maintain the voltage stability of the microgrid, and
consequently, the wider power system is proposed.
The loadability limit necessary to maintain the voltage stability of an interconnected
microgrid is determined by using bifurcation analysis to test for the singularity of the
network Jacobian and load differential equations with and without the contribution of
the DG. The maximum and minimum real and reactive power support permissible from
the DG is obtained from the loadability limit and used as the limiting factors in
controlling the real and reactive power contribution from the PV source. The designed
controller regulates the voltage output based on instantaneous power theory at the
point-of-common coupling (PCC) while the reactive power supply is controlled by means
of the power factor and reactive current droop method. The control method is
implemented in a modified IEEE 13-bus test feeder system using PSCAD® power system
analysis software and is applied to the model of a Tampa Electric® PV installation at
Lowry Park Zoo in Tampa, FL.
This dissertation accomplishes the systematic analysis of the voltage impact of a PV DGembedded
power distribution system. The method employed in this work bases the
contribution of the PV resource on the voltage stability margins of the microgrid rather
than the commonly used loss-of-load probability (LOLP) and effective load-carrying
capability (ELCC) measures. The results of the proposed method show good
improvement in the before-, during-, and post-start voltage levels at the motor
terminals. The voltage stability margin approach provides the utility a more useful
measure in sizing and locating PV resources to support the overall power system
stability in an emerging smart grid.
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Andersson, Karin. "Development of models for quantifying the environmental impact of demand response in electrical power distribution." Thesis, Uppsala universitet, Industriell teknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-263282.
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In this report some possible consequences of introducing demand response in the electric power grid are studied. Demand response is a part of the Smart Grid, which is a technology being developed to use our electric power grids more efficiently. Demand response programs aim to move people’s power usage over different times of the day, for example to distribute the power usage more evenly throughout the day or to permit a larger share of renewable, intermittent power sources in the system without making the delivery of electric power less stable. A distribution system operator (DSO) can encourage customers to shift their power usage between different hours by various tariffs, for example by using time-differentiated or power dependent tariffs. In this thesis, the change in power losses and possible environmental impact of introducing due to a power shift is studied. Power input curves from a DSO, Sala-Heby Energi AB, are studied and modified to simulate a power shift with an evened out electric power usage. The studies made show that in the best-case scenario, that is a electric power usage evened out to 100% each day, the power losses in the whole grid can be reduced with 2.6%. The environmental study shows that the result varies greatly with what method is chosen to do the calculations. The results are presented in kg CO2-equivalents (CO2e), and depending on method used they can either decrease or increase. The environmental study show that the environmental impact from the power usage is more dependent on the shift in power usage between hours than the decrease in electric power losses.
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Gudivada, Venkata Thulasi Prasad. "Impact of photovoltaic generators and electric vehicles on a weak low voltage distribution grid." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43810.
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In this thesis, the behaviour of a weak power distribution grid at the Point of Common Coupling (PCC) in the presence of a Photovoltaic (PV) inverter and Electric Vehicles (EV) as loads is analyzed. The grid connected to PV and EV has high impedance. The impact at PCC when the injected power varies in conjunction with the frequency and voltage deviation with a delay in inverter fed power is elaborated. Various measures such as peak shaving, coordinated charging, voltage drop correction have already been developed to mitigate the impact at PCC. These measures are observed on a combined EV and PV setup. In general, the grid tied inverter injects power based on an average grid voltage calculation at stable synchronization with the grid. If an error (for instance, an error in average grid voltage calculation) persists in such a case causing a loss in synchronization between the PV inverter and the grid, then a delay in the power injected may result in an oscillation at the PCC. A simple two bus system is considered to analyze the result of transportation delay. The delay and droop parameters of the PV inverter are altered whose results are quantitatively analyzed. The model abides the grid codes for active power reduction and static voltage support requirements. Further, the impact of a fault along with an inverter delay is analyzed. Simulative analysis is performed in the DIgSILENT PowerFactory software. To reduce the impact at PCC, performance criteria are analyzed whose parameters could be measured and altered. Scenarios are developed to analyze EV‟s impact in the presence and absence of storage and Distributed Generator (DG) that can be extended onto the micro grids.
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Romlie, Mohd Fakhizan. "Impact of energy storage on the stability and transmission efficiency of a remote grid." Thesis, University of Nottingham, 2014. http://eprints.nottingham.ac.uk/14266/.
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This thesis addresses a remote grid fed by a weak transmission line and a local source of renewable generation. Energy Storage System (ESS) is installed at the remote grid. The thesis investigates the use of the Energy Storage System in improving the overall system efficiency and increasing the power system stability for the transmission line and remote grid system. The Energy Storage System reduces transmission line losses and hence can improve the overall efficiency of the system. The key parameters that are significant to improving the overall system efficiency are derived and a simple mathematical analysis is undertaken to show the criteria for increased system efficiency. A PSCAD/EMTDC simulation is undertaken which is shown to be consistent with analysis both for simple and real wind profiles. For the case of stability investigation, a large Constant Power Load (CPL) is connected at the remote grid. This thesis performs the mathematical modelling and stability analysis of the combined CPL, grid, wind farm and energy storage. It is shown that CPLs fed by active PWM rectifiers are fundamentally stable if operated below the transmission line load-ability limit, and those fed by diode bridge rectifier can be unstable depending on filter values. It is revealed that the instability can be improved by control of auxiliary units such as an energy storage units. In order to reduce the simulation time required, a simplified model of a wind farm feeding a DFIG connected to a remote grid is proposed and compared with a detailed model using the PSCAD/EMTDC software.
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Mao, Daijiafan. "Integration of Plug-in Electric Vehicles into Power Grid: Impact Analysis and Infrastructure Planning." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1574632021559188.
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Mohlakoana, Nthabiseng. "Needs-based impact assessment of non-grid rural electrification : a case of Eastern Cape." Master's thesis, University of Cape Town, 2003. http://hdl.handle.net/11427/6893.
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Bibliography: leaves 71-74.This thesis explores issues of electrification in the rural areas of the Eastern Cape. First the set of issues explored are the rural areas electrification and general development background issues, taking the electrification from the early 1990s as the point of departure. Non-grid electrified, grid-electrified and non-electrified households in six Eastern Cape province areas were interviewed to gather information on their energy consumption. The research was undertaken to explore households' energy uses and to measure the impacts of having both grid and non-grid electricity. Socio-economic backgrounds of researched households are analysed to explore their contribution and influence to the types of energy sources used by households. By exploring socioeconomic backgrounds, a picture is given of conditions that drive rural households to use different types of energy. By comparing the electrified and non-electrified households. the thesis explores and explains how the transition and switching from one fuel to the other is made within these households. Lastly, there is also an analysis of the way different electricity supply options used in the rural areas affect the way people use energy. This includes discussion as to whether different electricity supply options are accepted better than others and the reasons for this. The conclusions drawn from the research done for this thesis shows that energy is a key component of rural development, yet energy demand (in terms of electricity use) in rural areas is low due to their underdeveloped nature. Even if modem energy is delivered to rural poor, households are often faced with very restricted income which severely limits energy use especially for thermal applications. These problems have to be addressed as a whole. In order to satisfy needs of people in rural areas. the provision of electricity, either grid or off-grid must hand in hand with integrated local development through which poverty as a whole may be addressed.
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Orebrand, Idah, Max Rosvall, and Melissa Eklund. "Microgeneration of PV power and its impact on power quality in the distribution grid." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-324313.
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This bachelor thesis examines the impacts of installed microgeneration of PV power in the distribution grid. The thesis examines the selected distribution grids power quality and how it is affected in terms of exceeding currents, voltages and reverse power flows and how the future trend of microgeneration of PV power will develop. A case study is made on Gotland with the support of the distribution grid owner, GEAB. Three of GEAB's distribution grids with different customer configurations and grid structures are being used to create different case scenarios. The production from the PV plants is calculated with production data from a project that GEAB performed with PV plants but dismantled in 2016. The Newton-Raphson power flow method is used to run the simulations of the grids with different amount of installed PV power. The results show that exceeding maximum current is the first parameter to limit and affect the power quality for all grids. After this the three grids can handle different amounts of installed PV power with respect of the remaining parameters. The simulations also show that losses in the grid are reduced due to installations of PV plants, although their small magnitude do not make them a significant aspect to consider when evaluating microgeneration in the distribution grid. When comparing to future scenarios it is concluded that the grids are dimensioned to handle a various amount of installed microgeneration without the power quality being affected. To analyse the sensitivity of the results a sensitivity analysis is performed on the slack node voltage by alternating the voltage level. The result indicates that a higher slack node voltage gives more exceeding voltages for the city power grid and the two rural grids.
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Knapp, Sandra V. "Does GRID Alternatives Impact Greenhouse Gas Emissions Reduction Targets in Central Coast Climate Action Plans?" DigitalCommons@CalPoly, 2016. https://digitalcommons.calpoly.edu/theses/1613.
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As of March 2016, GRID Alternatives’ 179 solar electric system installations on low-income housing contributed 103 metric tons of carbon (MT CO2e) emissions reduction for the climate action plans’ Energy or Renewable Energy climate action measures that pertain to solar electric installations in the cities of: Arroyo Grande, Atascadero, Paso Robles, and San Luis Obispo and San Luis Obispo County.
In 2007, the San Luis Obispo County Air Pollution Control District (APCD) created a team of government agencies to design climate action plans (CAP) that met the emission reduction goals set out by AB 32 and the 2008 Climate Change Scoping Plan (Rincon Consultants, 2014, p. 1-2).
Each CAP outlines its greenhouse gas (GHG) baseline emissions and GHG emissions reduction targets in metric tons of carbon (MT CO2e) and identifies climate action measures to reach GHG emissions reduction targets. The climate action measure that pertains to Energy or Renewable Energy, specifically solar electric system installations, is examined in this study.
GRID Alternatives, a non-profit solar installer that implements its Solar Affordable Housing Program, was selected by the California Public Utilities Commission (CPUC) in 2008, to serve as the statewide program manager for the California Solar Initiative’s $108 million incentive program called the Single-family Affordable Solar Homes (SASH) program, which is the country's first dedicated solar rebate program for low-income families (GRID, 2016a, p. 2). In 2010, GRID Alternatives opened its Central Coast office in Atascadero to serve five central coast counties and tracks CO2 emission reductions for each installation.
My objective is to determine the impact that GRID Alternatives’ solar electric installations in the cities of Arroyo Grande, Atascadero, Paso Robles, and San Luis Obispo and in San Luis Obispo County have on their respective CAPs’ GHG emissions reduction targets for the Energy or Renewable Energy climate action measure that pertains to solar electric installations.
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Sahoo, Smrutirekha. "Impact Study: Photo-voltaic Distributed Generation on Power System." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-32369.
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The grid-connected photo-voltaic (PV) system is one of the most promising renewable energy solutions which offers many benefits to both the end user and the utility network and thus it has gained the popularity over the last few decades. However, due to the very nature of its invariability and weather dependencies, the large scale integration of this type of distributed generation has created challenges for the network operator while maintaining the quality of the power supply and also for reliable and safe operations of the grids. In this study, the behavioral impact of large scale PV system integration which are both steady and dynamic in nature was studied. An aggregate PV model suited to study the impacts was built using MATLAB/Simulink. The integration impacts of PV power to existing grids were studied with focus on the low voltage residential distribution grids of Mälarenergi Elnät AB (10/0.4 kV). The steady state impacts were related to voltage profile, network loss. It was found that the PV generation at the load end undisputedly improves the voltage profile of the grid especially for the load buses which are situated at farther end of the grid. Further, with regard to the overvoltage issue, which is generally a concern during the low load demand period it was concluded that, at a 50% PV penetration level, the voltage level for the load buses is within the limit of 103% as prescribed by the regulator excepting for few load buses. The voltage level for load buses which deviate from the regulatory requirement are located at distance of 1200 meter or further away from the substation. The dynamic impact studied were for voltage unbalancing in the grid, which was found to have greater impact at the load buses which is located farther compared to a bus located nearer to the substation. With respect to impact study related to introduction of harmonics to the grid due to PV system integration, it was found that amount of harmonic content which was measured as total harmonic distortion (THD) multiplies with integration of more number of PV system. For a 50 % penetration level of PV, the introduced harmonics into the representative network is very minimal. Also, it was observed from the simulation study that THD content are be less when the grid operates at low load condition with high solar irradiance compared to lower irradiance and high load condition.
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Morales, Betancourt Ricardo. "On the representation of sub-grid scale phenomena and its impact on clouds properties and climate." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50373.
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This thesis addresses a series of questions related to the problem of achieving reliable and physically consistent representations of aerosol-cloud interaction in global circulation models (GCM). In-situ data and modeling tools are used to develop and evaluate novel parameterization schemes for the process of aerosol activation for applications in GCM simulations. Atmospheric models of different complexity were utilized, ranging from detailed Lagrangian parcel model simulations of the condensational growth of droplets, to one-dimensional single column model with aerosol and cloud microphysics, and finally GCM simulations performed with the Community Atmosphere Model (CAM). A scheme for mapping the sub-grid scale variability of cloud droplet number concentrations (CDNC) to a number of microphysical process rates in a GCM was tested, finding that neglecting this impact can have substantial influences in the integrated cloud properties. A comprehensive comparison and evaluation of two widely used, physically-based activation parameterizations was performed in the framework of CAM5.1. This was achieved by utilizing a numerical adjoint sensitivity approach to comprehensively investigate their response under the wide range of aerosol and dynamical conditions encountered in GCM simulations. As a result of this, the specific variables responsible for the observed differences in the physical response across parameterizations are encountered, leading to further parameterization improvement.
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Eriksson, Erica. "An assessment of the solar and battery storage potential in Hammarby Sjöstad and its grid impact." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-289378.
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Urbanization, technological development, increasing population and fast transition towards electricity in both industries and the car sector bring challenges to the Swedish power network. The increasingdemand of both electricity and capacity within the cities create demand of the networks. The Swedish power system has a history to be secure, reliable and sustainable. That there was lack of power and grid was news for many people in 2019. It is not tomorrow’s problem that can be solved easily, but rather todays’ tough challenge that will affect the development of cities in Sweden. The local network owner in Stockholm have already faced the problem, they can’t soak enough capacity from the transmission network in order to fulfill their customers’ demands. Reinvestments and developments of the transmission network are the main solutions, but it takes years before the power system have cached up with the fast growing demand. Local actions, within the city boundaries, that decrease the capacity demand from the transmission network are required for a sustainable development of the Swedish cities. At the same time is it a high interest from both cities and property owner to become self-sufficient by produce, utilize and store renewable energy locally. This study aims to evaluate the potential of solar and battery storage in Hammarby Sjöstad, Stockholm, and its grid impact. Key areas within the city district that have highest potential are identified. It is also evaluated to what extent Hammarby Sjöstad can be self-sufficient and how much of the produced electricity that can be self-consumed. The two technologies impact on the power and energy demand as well as if it can help alleviate the capacity problem are analyzed. An estimation of the suitable roof area for solar were made for each building to evaluate the potential of PV and storage. Three scenarios were developed, Reference scenario, which only included loads, Sun in Sjöstan that had 5.57 MW of PV and PV-BESS in Sjöstan, which also included 3.72 MW of storage. A dispatch strategy was developed to decrease the peak power demands. From power flow analysis of Hammarby Sjöstads power network and real based electricity data was results of how the power grid was affected received. The potential to reduce power and energy demand in order to have a positive effect on the challenge of grid capacity were also evaluated for a week in May and October. The potential of PV in Hammarby Sjöstad is large, where some areas are more beneficial than others. During spring months when there are good weather conditions can both the power and energy demands be reduced significantly. With PV can the high morning peaks be decreased. Together with storage is it possible to decrease the demand of bought electricity during times when the PV doesn’t produce any electricity. Evening peaks, that occur when the sun has set, can only be reduced by storage. The reduction of power and energy are less in October since the weather conditions are worse for PV then. Less sunshine hours and lower irradiation lead to that less electricity are produced. With PV can only the smaller morning peaks be reduced, when it’s actually the evening peaks that are the main challenge. Due to very high power demands are almost all solar power utilized onsite and selfconsumption of nearly 100% in both May and October. Because of this won’t the batteries increase the self-consumption or reduce the bough energy. Instead, together with PV have it a high potential to reduce the peaks, which are the challenge of today’s power system. Even if all suitable roofs are covered with solar and all produced electricity is utilized can only a fraction of the total electricity demand in Hammarby Sjöstad be covered. It takes more measures than PV and storage in order to become a more sustainable and self-sufficient city district. The conclusion of this thesis are that there is high potential for PV and battery in Hammarby Sjöstad and together can it reduce the power peaks and help alleviate with capacity demand. For future recharge is it recommended to develop other discharge strategies of the batteries and size them for each network area. By scaling up the result for the entire Stockholm is it possible to evaluate the potential to help alleviate the capacity problem on a higher level.Urbaniseringen, den teknisk utveckling, populationsökningen och den snabba övergången till elektricitet inom både industrier och bil flottan medför stora utmaningar för Sveriges elsystem. Det ökade behovet av både elektricitet och kapacitet i städerna sätter stor press. Historiskt sett har det svenska elsystemet alltid varit säkert, tillförlitligt och hållbart. Bristen av effekt och nätkapacitet är inte morgondagens problem, som enkelt kan lösas, utan effekterna märks av i våra städer redan idag. För att fortsätta en hållbar utveckling och inte låta dess följder bli allt för stora krävs åtgärder redan nu. Ellevio, det lokala nätbolaget i Stockholm, har märkt effekterna av ett förlegat elsystem. De kan inte ta ut tillräckligt stor kapacitet från det övre tranmissionsnätet för att möta deras kunders behov. Investeringar och utbyggnad av tranmissionsnätet är lösningar på problemen, men dessa lösningar tar lång tid att genomföra. Det är många år till dess att elnäten har utvecklats tillräckligt för att kunna möta det allt ökade behovet. Därför krävs det lokala åtgärder inom städernas regionala och lokala elnät som minskar behovet av nät kapacitet från transmissionsnätet. Det finns för bli själv försörjande på energi genom att producera, använda och lagra förnybar energi lokalt. Syftet med studien är att utvärdera potentialen för solceller och batterilager i Hammarby Sjöstad, Stockholm, samt analysera vilka effekter det har på elnätet. Vilka områden som är mest lämpade för systemen utvärderas. Egenanvändningen av solel samt stadsdelens potential till att bli självförsörjande utvärderas också. Till sist utvärderas ifall två teknologier kan minska nätkapacitetsbristen. För att beräkna potentialen av solceller och batterilager i Hammarby Sjöstad gjordes en sammanställning över vilka tak som var lämpliga för solceller. Tre olika scenarier utformades; Reference scenario som endast innefattade elkonsumtion, PV in Sjöstan som inkluderade 5.57 MW solceller samt PV-BESS in Sjöstan där 3.72 MW batterier också ingick. Strategi för urladdning av batterierna togs fram och modellerades. Genom simuleringar för elnätet i Hammarby Sjöstad med riktig data för elbehovet, kunde resultat för hur elsystemet påverkades i de olika scenarierna påvisas. Potentialen till att minska effekt- och energibehovet i syfte att ha en positiv effekt på nätkapacitetsbristen utvärderades därefter för de olika scenarierna för en vecka i maj och oktober. Potentialen för solceller i Hammarby Sjöstad är väldigt stor, där några områden lämpar sig mer än andra. Under vår och sommaren när vädret är gynnsamt för solceller minskas både effekt- och energibehovet avsevärt. Denna tid på året kan några av de problematiska effekttopparna reduceras med endast solceller. Under hösten är förutsättningarna för produktion av solel sämre vilket gör att minskningen av effekt och el är mindre. Färre soltimmar och lägre sol instrålning leder till lägre produktion av effekt och energi. Under denna tid på året kan endast mornarnas effekttoppar reduceras med bara solceller, när det stora problemet är de höga effekterna kvällstid. Effekttoppar som sker tider då solen inte är uppe kan endast reduceras med batterilager. På grund av högt effektbehov året runt så är egenanvändningen nästintill 100 procent i både maj och oktober. Därför så bidrar inte batterilagren till lägre energibehov, istället så reducerar de behovet av effekt vid hög last. Något som egentligen är ett av de stora problemen i dagens elsystem. Trots att solceller installeras på alla lämpliga tak kan endast en väldigt liten andel av det totala elbehovet täckas av solel. Detta påvisar att det krävs många fler åtgärder än endast solceller och batterilager för att bli en självförsörjande stadsdel. Om solceller och batterilager installeras i stor skala i hela Stockholm kan de bidra till att dämpa följderna av följderna av nätkapacitetsbristen. Det rekommenderas att i framtida forskning ta fram och studera resultateten av andra strategier för urladdning av batterierna samt att välja storlek på batterierna utifrån varje nätverksområde. Genom att skala upp resultaten från denna studie till hela Stockholm är det möjligt att utvärdera potentialen att lokalt kunna bidra till att minska effekterna av nätkapacitetsbristen.
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Marwan, Marwan. "Smart grid-demand side response model to mitigate prices and peak impact on the electrical system." Thesis, Queensland University of Technology, 2013. https://eprints.qut.edu.au/64180/1/Marwan_Marwan_Thesis.pdf.
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The aims of this project is to develop demand side response model which assists electricity consumers who are exposed to the market price through aggregator to manage the air-conditioning peak electricity demand. The main contribution of this research is to show how consumers can optimise the energy cost caused by the air-conditioning load considering the electricity market price and network overload. The model is tested with selected characteristics of the room, Queensland electricity market data from Australian Energy Market Operator and data from the Bureau of Statistics on temperatures in Brisbane, during weekdays on hot days from 2011 - 2012.
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Jadhav, Prakash. "Analytical and experimental investigations of the impact response of grid-stiffened E-glass/polypropylene (PP) composite panels /." Full text available from ProQuest UM Digital Dissertations, 2005. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1276391131&SrchMode=1&sid=2&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1185301529&clientId=22256.
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Chuang, Pamela. "Impact of shipping Ball-Grid-Array Notebook processors in tape and reel on the PC supply chain." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/73406.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science; in conjunction with the Leaders for Global Operations Program at MIT, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 72-76).
Today, approximately 90% of Intel notebook processors are packaged in PGA (Pin Grid Array) and 10% are packaged in BGA (Ball Grid Array). Intel has recently made a decision to transform the notebook industry by creating a new system size category called Ultrabook TM . In order to create such a thin form factor, PGA (Pin Grid Array) CPUs must now be offered as BGA (Ball Grid Array) CPUs to reduce the height of one of the taller items of the system. With the increased number of Ultrabooks [TM] being offered, the overall volume of BGA CPUs shipped by Intel is expected to increase. BGA CPUs can be shipped in one of two mediums: tape and reel or trays. By making tape and reel available, customers would be able to utilize the benefit of a more efficient pick and place process on their surface mount technology (SMT) lines compared to when using trays. However, from Intel's standpoint, BGA CPUs have a very high product mix, and shipping BGA CPUs in trays allows Intel to ship in smaller order quantities to customers. Intel currently ships its BGA CPUs in trays. Because BGA processors used in Ultrabook m and other systems will become the majority of processor volume, some customers have made a request to have BGA CPUs delivered in tape and reel in addition to trays. The objective of the thesis is to determine if packaging CPUs in tape and reel in conjunction with tray packaging will improve overall CPU supply chain performance. Based on the analysis, we conclude that tape and reel should not be offered due to the minimal savings received by its ODM customers, and the expense that would be incurred by Intel based on current market conditions. Key drivers that influence this decision on the Intel side include SKU management issues, lack of shipping efficiency, and capital equipment purchase costs. From the customer point of view, it was identified that the request came from ODM Surface Mount Technology line managers and did not take into consideration procurement or inventory holding issues.
by Pamela Chuang.
S.M.
M.B.A.
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Forde, Elaine. "Planning regimes on and off the grid : low-impact dwelling, activism and the state in west Wales." Thesis, Goldsmiths College (University of London), 2016. http://research.gold.ac.uk/19190/.
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This thesis presents ethnographic research into the practice of off-grid, low-impact dwelling in West Wales. It asks how participants imagine, construct and live lives that are low impact, and explores how this brings them into conflict with local authority planners about the proper use of land. The thesis extends anthropological theories of dwelling to critique the domestic development agenda. It demonstrates ways that low-impact dwelling is qualitatively different to low-impact development. This important distinction provides an original contribution to the existing body of literature about UK low-impact development, by revealing how inequalities implicit in the notion of development shape the possibilities for alternative models of rural land use. Research was conducted within an ecovillage in West Wales for a period of 15 months between 2010 and 2011. Supplementary visits and short stays were arranged with participants in other sites, both ecovillages and independent autonomous dwellings. This immersive approach built a sound network of low-impact practitioners, who provided semi-structured and unstructured interviews, and opportunities for participant observation. A new planning rationality has consolidated around the idea of sustainable development; policies in favour of low-impact development, but which remain subject to regulation, standards and models to ensure compliance with a matrix of requirements, are one of the results. Research participants and the Welsh Assembly Government hold divergent notions of low-impact dwelling in spite of models and mechanisms which would contain them both. Low-impact dwellers reject this system, or “grid”, and in doing so construct a hoped-for future in the present, a form of everyday activism.
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Kirby, Elizabeth Ann. "Quantification of the Impact of Intermittent Renewable Penetration Levels on Power Grid Frequency Performance Using Dynamic Modeling." ScholarWorks @ UVM, 2015. http://scholarworks.uvm.edu/graddis/519.
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As the technology behind renewable energy sources becomes more advanced and cost-effective, these sources have become an ever-increasing portion of the generation portfolios of power systems across the country. While the shift away from non-renewable resources is generally considered beneficial, the fact remains that intermittent renewable sources present special challenges associated with their unique operating characteristics. Because of the high variability of intermittent renewables, the frequency performance of the system to which they are connected can degrade. Generators assigned to regulate frequency, keeping it close to the desired 60 Hz, are forced to ramp up and down quickly in order to offset the rise and fall of the variable resources (in addition to the rise and fall of load), causing transient frequency deviations, power swings, major interface transfer variations and other significant issues.
This research measures the impact of intermittent renewable resource penetration level on power system frequency performance, and offers methods for managing that performance. Currently, the generally accepted amount of regulation (rapidly-dispatchable reserve, used as a supplement to base generation on a short time scale to avoid performance issues) is 1% of peak load. Because of the high variability associated with intermittent renewables, including wind generation (the focus of this thesis), it is expected that this amount of regulation must increase in order to maintain adequate system frequency performance. Thus, the primary objective of this thesis is to quantify the amount of regulation necessary to maintain adequate frequency performance as a function of the penetration level of wind generation.
Presently, balancing resource requirements are computed, in both industry and in the research literature, using static models, which rely entirely on statistical manipulation of net load, failing to capture the intricacies of dynamic system and generator interactions. Using a dynamic model with high temporal resolution data, instead of these statistical models, this thesis confirms the need for additional regulation as wind generation penetration increases. But beyond that, our research demonstrates an exponentially increasing relationship between necessary regulation and wind generation percentage, indicating that, without further technological breakthroughs, there is a practical limit to the amount of wind generation that a typical system can accommodate. Furthermore, we compare our dynamic model results with those of the statistical models, and show that the majority of current statistical models substantially under-predict the necessary amount of regulation to accommodate significant amounts of wind generation. Finally, we verify that the ramping capability of the regulating generators impacts the amount of necessary regulation, although it is generally ignored in current analysis and related literature.
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Grøtterud, Magnus. "Analysis of the Slow Floating in Grid Frequency of the Nordic Power System : Impact of Hydraulic System Characteristics." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elkraftteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19024.
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This Master's Thesis work deals with the analysis of the observed slow floating in the grid frequency of the Nordic power system. Measurements indicate that the frequency of this floating or oscillation is around 11-17 mHz. The reason for this floating is not known to this date, but it is suspected that it will increase the wear of the turbines that are providing primary regulation. In this work possible interaction between the hydraulic system and the power system has been emphasized and whether the governor settings may influence the slow floating, or not. The hydraulic models for the water conduit and turbine that are implemented in power system analysis tools are often simplified. In this Master's Thesis a hydraulic model that includes the effect of water hammer, surge tank and head loss has been implemented in the analysis tool SIMPOW. A three-machine equivalent of the Norwegian and Swedish power system has been established to study the response of the frequency after a severe disturbance.It has been demonstrated that for a severe disturbance a low-frequency mass oscillation will occur in the tunnel between the surge tank and the reservoir in the model. This will cause an oscillation in the pressure at the turbine which affects the grid frequency. The frequency of the mass oscillation depends on the construction of the tunnel and surge tank and will be different for every hydro power plant. Frequencies in the range of 5-11 mHz was found for the model used in this Thesis. It has been illustrated that with different characteristics for the two hydro power plants in the model, the floating in power system frequency will be the sum of the mass oscillations, which is assumed to be the case for the real power system. The governor parameters are found to have little influence on the damping of the low-frequency oscillations. For further work a study of the impact of several different hydro power plants in a more extensive equivalent of the Nordic power system is suggested. For this work emphasis should be on finding parameters for typical Norwegian and Swedish hydro power plants.
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Price, Carmen S. "Conscious Living: A Look at Two Low-Impact Intentional Communities." Digital Archive @ GSU, 2011. http://digitalarchive.gsu.edu/art_design_theses/81.
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Conscious Living is a series of visual solutions to a current and escalating problem in increasingly populated modern societies between its citizens and the environment they inhabit. Documented in the photographs are two dissimilar intentional communities that both strive to operate harmoniously with the surrounding ecology.
Originally intending to address the misconception that low impact living is uncomfortable or unsatisfying, this research and my firsthand experience has led to conclusions that are more complex and less didactic. Although the images focus on these two communities, ultimately the intention is to provide the viewer with new perspectives on these niche groups, as well as options to implement low impact alternatives to their lifestyle.
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Biswas, Shuchismita. "Understanding the Impacts of Data Integrity Attacks in the Context of Transactive Control Systems." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/86851.
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The rapid growth of internet-connected smart devices capable of exchanging energy price information and adaptively controlling the consumption of connected loads, has paved the way for transactive control to make inroads in the modern grid. Transactive control frameworks integrate the wholesale and retail energy markets, and enable active participation of end users, thereby playing a key role in managing the rising number of distributed assets.However, the use of internet for the communication of data among the building, distribution,and transmission levels makes the system susceptible to external intrusions. A skilled adversary can potentially manipulate the exchanged data with the intention to inflict damage to the system or increase financial gains. In this thesis, the effect of such data integrity attacks on information exchanged between the distribution systems operator and end-users is investigated. Impact on grid operations is evaluated using different categories like operational, financial, user comfort and reliability parameters. It is shown that attack impact depends on a number of factors like attack duration, time of attack, penetration rate etc besides the attack magnitude. The effect of an attack continues to persist for some time after its removal and hence effective detection and mitigation strategies will be required to ensure system resilience and robustness.Master of Science
Transactive energy is a framework where price-responsive loads adjust their energy consumption at a certain time according to the real-time energy price sent by the utility. Field demonstrations in recent years have shown that transactive control can effectively manage grid objectives and also monetarily benefit both the electric utility and end-users. Therefore, transactive energy is expected to make inroads into conventional grid operations in the next few years. As successful operation of such a market depends on the information exchanged among different stakeholders, a malicious adversary may try to inject false data and affect system operations. This thesis investigates how manipulating data in the transactive energy platform affects system operations and financial gains of different stakeholders. Understanding system behavior under attack conditions will help in formulating effective detection and mitigation strategies and enhancing system resilience.
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Kvalheim, Miles R. "Residental Electricity Demand: An Analysis of the Current and Future United States Electricity Grid and Its Impact on Power Consumption." Scholarship @ Claremont, 2012. http://scholarship.claremont.edu/cmc_theses/352.
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The nature of electrical power requires specific infrastructure in order to operate adequately. Currently, the United States electricity grid contains a number of bottlenecking inefficiencies that arise from the aging infrastructure of the system. This paper examines the current state of the United States electricity grid, how potential changes in weather variables can affect the electricity consumption of residential consumers, and how implementation of Smart Grid technology can potentially mitigate these issues. It is determined through regression analysis that each weather variable that was tested proves significant for at least one of the consumers compared. This indicates that there is an enormous magnitude of individual variables that factor into residential electricity consumption and that more efficient and integrated electricity practices are necessary to optimize efficiency.
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Gebro, Per. "National scale impact of the Stockholm Royal Seaport project : Demand response and load-shift for Swedish apartment customers." Thesis, KTH, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-120118.
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The Swedish electrical power system faces many challenges. Stricter environmental and economic demands require a more efficient use of both the transmission and distribution grids as well as the production capabilities. Since the Swedish national demand of electricity is fluctuating, the system has always been dimensioned to meet the periods of high demand, resulting in a low utilization of the system. To meet these challenges, the concept of a “Smart Grid” has been phrased. One of the most important goals of a Smart Grid is to enable end-consumers to participate more actively in the energy market. One way to do this is through “load-shifting” where consumption (or loads) are moved from hours of high demand (peak hours) to hours of low demand (off-peak hours). Load-shifting is a part of a set of intentional consumption modifications denoted “Demand Response” (DR) and is deemed to be one of the most important tools of the Smart Grid. In Sweden, a Smart Grid project called the Stockholm Royal Seaport (SRS) project is currently taking place. The project have phrased a hypotheses regarding load-shifting called the “Active customer” scenario, in which a customer load-shifts 5-15 % of his electricity consumption. To facilitate this scenario, the SRS project uses an end-consumer price model for electricity, called the SRS price model, as well as technological and market solutions not yet available on a national scale. This study investigates what impact the results from the SRS pilot project might have if implemented for private apartment end-consumers on a Swedish national scale. The study is divided into three parts. The first part investigates the challenges of a national scale implementation of private apartment end-consumer DR and the SRS price model. The second part investigates what the impact would be if the entire Swedish private apartment end-consumer sector where to act in accordance with the Active customer scenario. The third part consists of a sensitivity analysis. Four challenges for a national private apartment end-consumer load-shift implementation have been elicited. They are; the lack of easily moveable loads in a foreseeable future, the heterogeneous cost of distribution, the suggested price models low peak to off-peak price ratio and the comparatively small cost of electricity of the private apartment end-consumers. The SRS price model is deemed to give a clear economic incentive for load-shift of private apartment end-consumer without electric heating. However, the incentive might be considered too weak with yearly savings of 48-165 SEK for a 15 % load-shift, depending on apartment consumption. This corresponds to yearly savings of 124 to 429 million SEK for the entire customer segment. These challenges are deemed to be of a non-technical character, but rather of a marketing and communication nature. The impact of a fully implemented national private apartment end-consumer load-shift in accordance with the Active customer scenario and the SRS price model is deemed to be beneficial from an overall power system point of view. However, the impact on the private apartment end-consumer national demand is small in comparison with other plausible system developments, such as energy demand reductions due to more efficient lighting solutions. The sensitivity analysis of private apartment end-consumer cost savings when acting in accordance with the Active customer scenario indicates that the percentage savings may increase in the future when considering more volatile prices for electric energy or the implementation of a time differentiated energy tax.
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Williams, Tania Carol. "The impact of increased grid resolution on the mixed layer depth variability in the South Atlantic Ocean and Southern Ocean." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20814.
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The Southern Ocean plays a major role in global climate system. An understanding of Southern Ocean dynamics allows for a better understanding of the carbon cycle and possible future climate conditions. Earth System Models are used to study Southern Ocean dynamics and are currently producing reliable global annual carbon uptake but have limiting seasonal abilities. These models produce dependable results on a global scale, with more conflicting results on a basin scale. Here we study the impact of mesoscale variability on the Mixed Layer Depth in the Sub-Tropical and Sub-Antarctic Zone of the South Atlantic. The region is hugely impacted by the mesoscale variability as a result of the South African boundary currents. We use two regional simulations both at 1/4o resolution, with one model containing online nested child domain over the South African boundary currents (1/12o resolution). The inter-annual simulations both use the same forcing which allow for a comparison study between the two models. Both the nested and standalone model are able to capture the large scale oceanographic features in the domain. The biggest difference is seen in the Agulhas Current region, where the nested model simulates better mesoscale features, resulting in a fairly accurate position of the Agulhas retroflection and return current. The standalone model contains a high temperature and salinity bias which influences the vertical structure of the water column. Both models are able to simulate the seasonality of the MLD in the Sub-Tropical and Sub-Antarctic Zone in the Atlantic sector. The models overestimate MLD in regions closer to the boundary currents. In the nested model the presence of increased mesoscale features promotes stratification of the water column. The differences seen in the MLD of the two models are linked to the temperature and salinity bias in the standalone model as well as the increased mesoscale variability in the nested model.
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Baggio, Martina [Verfasser]. "Volume of Fluid Numerical Simulation of Drop Impact on Superhydrophobic Complex Solid Surfaces Embedded in a Staggered Cartesian Grid / Martina Baggio." München : Verlag Dr. Hut, 2020. http://d-nb.info/1220567930/34.
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Daun, Kevin. "Impact of energy storage technologies in a distribution grid : An analysis of Key Performance Indicators relating to a local grid’s performance characteristics." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-55367.
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The energy system is undergoing a transformation on a never before witnessed scale. The changes are driven by global market forces and technological advancements, improving on a seemingly exponential scale. This in turn has led to the price of both renewables and the accompanying technology decrease over time, making the transition into renewables more economically viable. The drawback of variable renewable energy is that it is variable and dependent on the surrounding environment. Therefore, storing the energy during hours of production, to be used at a later stage when energy demand is higher is becoming ever more important and an attractive option. The purpose of this degree project is to, from a set of performance indicators, evaluate three different energy storage technologies and their respective impact on a distribution grid. The examined storage technologies are: Batteries, Capacitators and a H2 Fuel cell. A literature study was performed in order to find out how grid performance is evaluated, and how the different storage technologies operate. The obtained literature comes from scientific reports, and papers, found by utilizing Mälardalens University library-database. A model representing a Swedish grid with a connection point to the distribution side was created. The model is taken from previous credited work, and customized to fit the operational parameters of a Swedish grid. It was decided that the key indicators for evaluating the state of a grid was to look at the: voltage- and frequency variations, load factor, capacity factor and the overall system efficiency. The simulation is a discrete time simulation that utilizes parameters indicative of one full day of data. The results showed that, from a technological standpoint, the supercapacitor performed better in more categories than the Li-ion battery and H2 fuel cell. However, the Li-ion battery reduced the peaks of the frequency measurements which is a key metric when deciding on grid health. Also, there is the added benefit of the battery and fuel cell of having a longer operational time before the state of charge is depleted. This increases the flexibility of the technology and could therefore be more beneficial in other applications where power supply is more scarce.
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Attya, Ayman Bakry Taha [Verfasser], Thomas [Akademischer Betreuer] Hartkopf, and Griepentrog [Akademischer Betreuer] Gerd. "Wind energy penetgration impact on grid frequency during normal operation and frequency deviations / Ayman Bakry Taha Attya. Betreuer: Thomas Hartkopf ; Griepentrog Gerd." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2014. http://d-nb.info/1112268669/34.
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Mustafa, Mehran. "ANALYZING THE IMPACT OF PLUG-IN ELECTRIC VEHICLE’S CHARGING LOAD ON THE GRID BASED ON DRIVER’S PERSONAL ATTITUDES TOWARDS PEV USAGE AND CHARGING." OpenSIUC, 2021. https://opensiuc.lib.siu.edu/dissertations/1942.
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Today, the transport sector is responsible for nearly one-quarter of global energy-related direct carbon-dioxide (CO2) emissions and is a significant contributor to air pollution [1]. In the United States, the transportation sector has the highest share (28%) in the mix of green-house gas (GHG) sources [2]. Some of the more developed nations across the globe are now committed to improve the climate and air quality. Countries like China, Europe and the United States are front runners in introducing ambitions policies to incentivize the production and adoption of plug-in electric vehicles (PEV’s). Along with the expected benefits of PEV uptake, large scale deployment poses a challenge for the electric grid, especially at the distribution level, since the charging load of an PEV is substantial. This load is dependent not only on the characteristics of the PEV, but also on its use and charging habits of its user(s). Since a PEV can be directly plugged into the grid at any available point, which may be spatially anywhere in the utility’s service area, it is important to model its accurate use and charging behavior of the users. Having precise knowledge of the load profile, the utilities can have a better economic solution to balancing the supply and demand. In this dissertation, an agent-based model is developed that estimates the impact of charging load of PEVs on the grid. It is based on reasonably realistic diverse human behavior pertaining to day-to-day driving patterns and charging practices and their effect on each other. The model portrays the heterogenous, spatial and temporal nature of this load, which depends on the habits and the interaction among different agents. The model mimics the heterogeneity of choices made by human drivers and its effect on the charging choices of other drivers, which is an important element to consider when depicting human behavior. The model uses travel statistics of conventional personally owned vehicles (POVs) from the National Household Travel Survey (NHTS) conducted by the Federal Highway Administration (FHWA) across different states of the United States from 2016 – 2017. The travel needs are modified to incorporate the effect of EV’s limited range and charging time requirements. A modified GIS map of Collinsville, IL, is used to implement the spatial requirements of travel, with, which highlight exact load points. The agent’s travel and charging choices are modelled with heterogenous rules of engagement with the environment and other agents. Common psychological effects of limited range, long charging times, and range anticipation are applied heterogeneously to all agents to create a macro environment. The resulting charging load is superimposed on existing substation transformer load and voltage profile is analyzed to study the impact of different charging strategies and charging infrastructure availability. Different case studies are analyzed to investigate the effect of the aggregated load of multiple charging points in the respective service areas of the distribution transformers.
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Liu, Lollo. "Life Cycle Assessment of a Lithium-Ion Battery pack for Energy storage Systems : - the environmental impact of a grid-connected battery energy storage system." Thesis, Uppsala University, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-428627.
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This thesis assessed the life-cycle environmental impact of a lithium-ion battery pack intended for energy storage applications. A model of the battery pack was made in the life-cycle assessment-tool, openLCA. The environmental impact assessment was conducted with the life-cycle impact assessment methods recommended in the Batteries Product Environmental Footprint Category Rules adopted by the European Commission (2016). The findings in this study showed that the most important parameter in the cradle-to-grave assessment was the use-stage losses, which can be reduced by using electricity grids with high sharesof renewable energy or by increase the round-trip efficiency of the battery system. However, for the cradle-to-gate assessment, five impact categories were found to be relevant. These categories were: climate change, acidification, fossil resource use, resource use (minerals and metals) and particulate matter. Furthermore, within these impact categories, four materials contributed to more than 65 % of all impact. These key materials were; nickel, aluminium, cobalt and graphite. Therefore, a recommendation to battery manufacturers is to prioritise sourcing these four key materials from sustainable suppliers to reduce the overall cradle-to-gate environmental impact. Lastly, by integrating recycling of the battery pack in the end-of-life-stage, it was possibleto achieve a net reduction of 9-20 % of the cradle-to-grave climate change, acidification and fossil resource use compared to not including recycling. Therefore, the development of efficient and large-scale recycling will likely play a major role in reducing the environmental impact from lithium-ion batteries in the future.
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Øren, Lars Pedersen. "System Analysis of Large-Scale Wind Power Integration in North-Western Europe : A study on the impact of large-scale wind power expansion and on the impact of a North Sea offshore grid." Thesis, Norwegian University of Science and Technology, Department of Electrical Power Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9020.
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Problem description: The objective of this project was to create a simple model of the European power system and to investigate the effect an increasing amount of on- and offshore wind power will have on the North European power market in general and Norway in particular. The scenarios contain increasing amounts of installed wind power capacity, both on- and offshore. Emphasis was to be on the area surrounding the North Sea. The project covers the following issues: - Simulations of simplified power system scenarios set in the years 2005, 2020 and 2030. - Study how an increasing amount of installed wind power will affect energy prices, power production distribution, and power transmission flows. - Investigate how an offshore grid consisting of interconnections between offshore wind farms will affect the system. The task: The simulations in this project were performed using simple power market model. The model included 6 price areas: Denmark West, Denmark East, Norway, Sweden/Finland, Germany and UCTE/Others. The existing market model was modified in the following manner: - Split Norway into three price areas: Norway North, Middle and South - Add the Netherlands - Add the United Kingdom - Add corresponding offshore price areas for areas neighbouring the North Sea. Wind series were generated for each wind generator using reanalysis data. Scenarios were created for the years 2005, 2020 and 2030. In these scenarios, wind power capacities are increasing as time progresses. The 2020 and 2030 scenarios have been simulated with two alternative grid configurations: one where the offshore areas are connected only to their respective onshore areas and one where the offshore areas are also interconnected in an offshore grid. In total 7 different scenarios were simulated. Results: Wind power is able to supplant a large share of energy originally produced by con-ventional thermal generators. The presence of an offshore grid does not have any dramatic effects on energy production for the system, though it is possible to conclude that the presence of an offshore grid may contribute to slightly shift the power system in favour of renewable energy sources. Wind power will cause a significant reduction in energy prices in all areas, resulting in reduced energy costs for the entire system. Analysis of lost wind and hydro power reveals the importance of sufficient transmission capacity when large quantities of wind power are added to the system. Scenario 4 features enormous quantities of lost hydro power in the North and Middle of Norway due to transmission limitations. Analyses of power transmissions reveal that the offshore grid is over-dimensioned. Rationalizing the grid by reducing transmission capacities to more realistic levels will give a more cost-effective solution. This was demonstrated by performing a quick simulation and analysis of a scenario featuring such a rationalized grid. Wind power will cause more frequent variations in hydro power generation, due to balancing needs. Parts of the increased variability in the hydro generators can be explained by the increasing amount of wind power in the system, while other parts are most likely caused by limitations in the simulation model itself. Conclusion: Given the number of assumptions made in the grid, in cost calculations and in the model at large, it is more important to focus on general trends than on concrete numerical values. However, it is clear that increasing the amount of on- and offshore wind power in the European power system will have a beneficial impact to society's energy costs. It is also clear that wind power has the potential to dramatically reduce CO2-emissions caused by power generation. The offshore grid seems to be more beneficial to the power producers than to consumers since it causes slightly higher energy prices and providing a measure of flexibility as to where offshore wind power production is sent. Wind power will present challenges, especially regarding transmission grid development. A sufficiently dimensioned grid will be essential to the successful implementation of such amounts of wind power, both with respect to profitability and in order to avoid waste of potential wind or hydro energy.
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Gadoury, Jonathan. "Impact of numerical grid spacing and time step size on vortex Rossby waves in secondary eyewall formation in a simulation of hurricane Wilma (2005)." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110599.
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To understand the impact of numerical grid spacing and time step size on vortex Rossby waves in hurricanes going through an eyewall replacement cycle, multiple simulations with identical parameterization but with different numerics were carried out using the WRF model on hurricane Wilma (2005). The method of Empirical Normal Modes was then applied on the dataset in order to find radially outward propagating vortex Rossby waves (VRWs). It was found that for varying grid lengths, using high resolution can resolve these VRWs while a mixture of gravity and vortex Rossby waves was propagating from the eyewall using coarse resolution. An examination of the divergence of the Eliassen-Palm flux showed that high resolution is required to form a secondary eyewall. In terms of varying the time step size, differences were noted in the eyewall replacement cycles as well as the final shape of the eyewall, implying that non-converging numerical errors can impact strongly the vortex Rossby waves and therefore the dynamics of the hurricane.Pour comprendre l'impact de l'espacement de grille numérique et la taille du pas de temps sur les ondes de Rossby de tourbillon (ORT) dans les ouragans affectés par un cycle de remplacement du mur de l'oeil, plusieurs simulations avec des paramètres identiques mais des données numériques changeantes ont été éffectuées en utilisant le modèle WRF sur l'ouragan Wilma (2005). La méthode des Modes Normaux Empiriques a été appliquée sur un ensemble de données afin de trouver des ORT se propageant radialement vers l'extérieur. Il a été trouvé que pour un espacement de grille variable, une haute résolution permet de résoudre ces ORT alors qu'en utilisant une résolution plus grossière, un mélange d'ondes gravitationnelles et d'ORT se propageaient à partir du mur de l'oeil. Une examination de la divergence du Flux d'Eliassen-Palm a montré qu'une haute résolution est requise pour former un deuxième mur. Pour le pas de temps variable, des différences ont été notées lors du cycle de remplacement du mur de l'oeil ainsi que sur la forme finale du mur de l'oeil, laissant entendre que la non-convergence des erreurs numériques peut fortement affecter les ORT et ainsi la dynamique de l'ouragan.
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Böing, Felix [Verfasser], Ulrich [Akademischer Betreuer] Wagner, Ulrich [Gutachter] Wagner, and Kai [Gutachter] Strunz. "Cross-sector assessment of CO2 abatement measures and their impact on the transmission grid / Felix Böing ; Gutachter: Ulrich Wagner, Kai Strunz ; Betreuer: Ulrich Wagner." München : Universitätsbibliothek der TU München, 2020. http://d-nb.info/122628745X/34.
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Li, Ying, Daven Henze, Darby Jack, and Patrick L. Kinney. "The Influence of Air Quality Model Resolution on Health Impact Assessment for Fine Particulate Matter and Its Components." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/10.
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Health impact assessments for fine particulate matter (PM2.5) often rely on simulated concentrations generated from air quality models. However, at the global level, these models often run at coarse resolutions, resulting in underestimates of peak concentrations in populated areas. This study aims to quantitatively examine the influence of model resolution on the estimates of mortality attributable to PM2.5 and its species in the USA. We use GEOS-Chem, a global 3-D model of atmospheric composition, to simulate the 2008 annual average concentrations of PM2.5 and its six species over North America. The model was run at a fine resolution of 0.5 × 0.66° and a coarse resolution of 2 × 2.5°, and mortality was calculated using output at the two resolutions. Using the fine-modeled concentrations, we estimate that 142,000 PM2.5-related deaths occurred in the USA in 2008, and the coarse resolution produces a national mortality estimate that is 8 % lower than the fine-model estimate. Our spatial analysis of mortality shows that coarse resolutions tend to substantially underestimate mortality in large urban centers. We also re-grid the fine-modeled concentrations to several coarser resolutions and repeat mortality calculation at these resolutions. We found that model resolution tends to have the greatest influence on mortality estimates associated with primary species and the least impact on dust-related mortality. Our findings provide evidence of possible biases in quantitative PM2.5 health impact assessments in applications of global atmospheric models at coarse spatial resolutions.
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Kang, Moon Hee. "Development of high-efficiency silicon solar cells and modeling the impact of system parameters on levelized cost of electricity." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47647.
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The objective of this thesis is to develop low-cost high-efficiency crystalline silicon solar cells which are at the right intersection of cost and performance to make photovoltaics (PV) affordable. The goal was addressed by improving the optical and electrical performance of silicon solar cells through process optimization, device modeling, clever cell design, fundamental understanding, and minimization of loss mechanisms. To define the right intersection of cost and performance, analytical models to assess the premium or value associated with efficiency, temperature coefficient, balance of system cost, and solar insolation were developed and detailed cost analysis was performed to quantify the impact of key system and financial parameters in the levelized cost of electricity from PV.
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Akhtar, Naveed [Verfasser], Bodo [Gutachter] Ahrens, and Stefan [Gutachter] Hagemann. "Climate modeling over the Mediterranean Sea: Impact of atmosphere-ocean coupling and atmospheric grid resolution on sea surface heat fluxes, medicanes, and Vb-cyclones / Naveed Akhtar ; Gutachter: Bodo Ahrens, Stefan Hagemann." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2019. http://d-nb.info/1183965176/34.
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Svensson, Dahlin Marcus. "Battery supported charging infrastructure for electric vehicles : And its impact on the overall electricity infrastructure." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264104.
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The Paris Agreement was formed in 2015 to reduce the environmental impact and limit the increase in temperature to 2°C compared to pre-industrial levels. It is believed that an electrification of the transport sector will reduce its negative environmental impact. To reach the goals set by the Paris Agreement we are in need of quick development towards an electrified fleet of vehicles. Despite this urgency electric vehicles (EVs) have failed to reach the majority of the market, instead it has stuck in the chasm between the early adopters and the early majority of the markets. This is due to three main challenges; EVs are relatively expensive compared to conventional petrol- and diesel-powered vehicles, EVs have an inadequate driving range, and the access to a functional charging infrastructure is limited. This thesis focuses on the third challenge regarding charging infrastructure. The charging infrastructure is dependent on the existing electricity distribution infrastructure, i.e. the grid. It is rather time-consuming and costly to strengthen the grid, which is deemed necessary for enabling a roll-out of a charging infrastructure that meets the needs of current and near-future EV operators. This research provides an alternative way of approaching the issues. Instead of strengthening the grid by digging up old cables it looks into the opportunities of incorporating stationary battery storages as a buffer between the EV charging stations and the grid connection point. This battery solution can reduce the power outtake and smoothen out the load from EV charging, thus limiting the impact of EV charging from a grid perspective. The research assesses what type of pathways this solution could follow to successfully drive the adoption of EVs. Furthermore, the study tries to understand how these solutions could be designed to deliver the necessary values regarding EV charging and reducing the overall power outtake from grid connection points. The thesis is carried out by analyzing collected quantitative and qualitative data through the lens of three main theories. These are transition theory, theory on eco-innovations, and theory on the diffusion of innovations. The thesis finds that the two pathways for a battery supported charging infrastructure that will be most efficient in speeding up the adoption rate of EVs is within a workplace and public charging setting in city and urban environments. For both pathways it is expected that a centralized concept, with one battery solution connected to several charging points, will be most feasible in the short-term, which is important as the need for developments are very urgent. The workplace charging will provide 3,6 kW AC-charging while the public charging provides 150 kW DC-charging. The solution is expected to be cost-efficient for specific locations, especially for public charging in city environments with strained grid infrastructures. The study provides an initial assessment for the city of Stockholm which indicates that the power outtake can be reduced by 63,5–112,2 MW in 2030. This means that the current grid infrastructure could support a larger number of EVs, thus reducing the greenhouse-gas emissions from the transport sector and bringing us closer to reaching the goals set by the Paris Agreement.Parisavtalet utformades år 2015 för att reducera vår klimatpåverkan och begränsa temperaturökningen till 2°C jämfört med nivåerna som rådde innan den industriella revolutionen. Förhoppningen är att en elektrifiering av transportsektorn kan reducera dess negativa klimatpåverkan. För att nå målen i Parisavtalet behövs en snabb omställning mot en elektrifiering av fordonsflottan. Trots situationens brådskande karaktär har elbilar fastnat i en klyfta mellan den begränsade tidiga marknaden och den sena marknaden, vilken utgör majoriteten av kunderna. Det finns tre primära anledningar till detta; elbilar är dyra jämfört med bensin- och dieseldrivna bilar, räckvidden för elbilar är otillräcklig, och det råder begränsad tillgång till en funktionell laddinfrastruktur. Den här studien fokuserar på den tredje anledningen kring otillräcklig laddinfrastruktur. Laddinfrastrukturen är beroende av det existerande elnätet och dess distributionskapacitet. En förstärkning av elnätet är i många fall nödvändig för att möjliggöra en utrullning av en laddinfrastruktur som möter dagens och morgondagens behov. Istället för att förstärka elnätet genom att gräva ner tjockare kablar så fokuserar denna studie på en alternativ lösning kring laddinfrastruktur sammankopplat med stationära batterilager. Batterilagret agerar som en buffert mellan anslutningspunkten till elnätet och laddningspunkten för elbilar. Genom att reducera effektuttaget och jämna ut lastkurvan för elbilsladdning kan en batterilösning begränsa den negativa påverkan det förväntas ha på elnätet. Studien undersöker vilka vägar denna batterilösning kan ta för att öka antalet elbilar i fordonsflottan. Efter att ha förstått vilka dessa lösningsvägar är så analyserar studien hur dessa lösningar kan vara uppbyggda för att erbjuda de efterfrågade och nödvändiga värdena för elbilsladdning och elnätets fortsatta funktionalitet. Studien bygger på analys av kvalitativa och kvantitativa data. Analysen utförs genom att applicera koncept hämtade från teorier kring teknologiska övergångar, miljöinnovationer och spridning av innovationer. De två lösningsområden som förväntas vara mest effektiva i att driva en ökning av antalet elbilar i Sverige är arbetsplatsladdning samt offentlig laddning i stadsmiljöer. En lösning med ett centraliserat batterisystem där en batterilösning är kopplat till flera laddstationer antas vara mest genomförbar på kort sikt, vilket anses vara centralt på grund av utmaningarnas brådskande karaktär. För arbetsplatsladdning tillhandahålls 3,6 kW AC-laddning och för offentlig laddning tillhandahålls 150 kW DC-laddning. Lösningarna förväntas vara kostnadseffektiva for specifika platser och användarprofiler, speciellt för offentlig laddning i stadsområden med ansträngda elnät. En initial uppskattning visar att en laddinfrastruktur kopplat till stationära batterilager inom de två lösningsområdena kan minska Stockholms effektuttag för elbilsladdning med 63,5–112,2 MW år 2030. Detta betyder att dagens elnät kan tillgodose ett ökat antal elbilar, vilka genererar färre utsläpp av växthusgaser och ger oss en bättre chans att nå Parisavtalets mål.
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Türker, Harun. "Véhicules électriques hybrides rechargeables : évaluation des impacts sur le réseau électrique et stratégies optimales de recharge." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENT110/document.
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Les engagements étatiques relatifs au secteur du transport promouvoient lapopularisation des véhicules rechargeables conformément aux exigences actuelles qu’ellessoient environnementales, techniques ou encore économiques. Ipso facto, ces travaux dethèse, assimilés à la thématique des Smart Grids, exposent une contribution à une gestionorientée du tryptique réseaux électriques, véhicules rechargeables et secteurs résidentiels.La première étape du travail consiste en l’évaluation des impacts liés à un taux de pénétrationélevé. Les travaux se sont ensuite focalisés sur deux problèmes importants qui sont latenue du plan de tension et le vieillissement accéléré des transformateurs de distributionHTA/BT, plus particulièrement ceux alimentant des secteurs résidentiels. Partant, desstratégies de modulation de la charge des batteries embarquées sont proposées et évaluées.Dans une seconde partie, en se basant sur l’hypothèse de bidirectionnalité énergétique duvéhicule électrique hybride rechargeable (Plug-in Hybrid Electric Vehicle - PHEV), estexploré les possibilités d’effacement de pointe et de diminution des puissances souscrites ;conformément au concept Vehicle-to-Home. Les aspects économiques ne sont pas évacués ;à ce titre la minimisation de la facture énergétique d’un logement fait l’objet d’un regardparticulier sous contrainte d’une tarification variable, le V2H servant de levier. Le véhiculebidirectionnel est enfin mis à contribution via une algorithmique adaptée à des fins deréglage du plan de tension et contribue ainsi au concept Vehicle-to-GridThe national commitments concerning terrestrial transport are promotingrechargeable vehicles according to actual environmental, technical or economicexigencies. To this end, the contribution of this thesis, related to the Smart Grids, coverssimultaneously the fields of electric utility grids, rechargeable vehicles, and residentialareas. The first step consists in the assessment the impacts caused by a highpenetration level. The research then focuses on two major problems : the voltage plan andthe aging rate of low voltage transformer, particularly those supplying residential areas.Therefore, unidirectional Plug-in Hybrid Electric Vehicles (PHEVs) charging strategieshave been proposed and evaluated. In the second part, based on the bidirectional PHEV,the possibility of consumption peak shaving and decrease of subscription contracts bothunder the concept Vehicle-to-Home are explored. The economics aspects are notignored, so a particular attention is paid of energy cost minimization for a housing undervariable pricing of energy constraint. The bidirectional vehicle is finally used in an adaptedalgorithmic for voltage plan control, thus contributing to the concept Vehicle-to-Grid
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Turker, Harun. "Véhicules électriques Hybrides Rechargeables : évaluation des Impacts sur le Réseau électrique et Stratégies Optimales de recharge." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00966055.
Full textAbstract:
Les engagements étatiques relatifs au secteur du transport promouvoient la popularisation des véhicules rechargeables conformément aux exigences actuelles qu'elles soient environnementales, techniques ou encore économiques. Ipso facto, ces travaux de thèse, assimilés à la thématique des Smart Grids, exposent une contribution à une gestion orientée du tryptique réseaux électriques, véhicules rechargeables et secteurs résidentiels. La première étape du travail consiste en l'évaluation des impacts liés à un taux de pénétration élevé. Les travaux se sont ensuite focalisés sur deux problèmes importants qui sont la tenue du plan de tension et le vieillissement accéléré des transformateurs de distribution HTA/BT, plus particulièrement ceux alimentant des secteurs résidentiels. Partant, des stratégies de modulation de la charge des batteries embarquées sont proposées et évaluées. Dans une seconde partie, en se basant sur l'hypothèse de bidirectionnalité énergétique du véhicule électrique hybride rechargeable (Plug-in Hybrid Electric Vehicle - PHEV), est exploré les possibilités d'effacement de pointe et de diminution des puissances souscrites ; conformément au concept Vehicle-to-Home. Les aspects économiques ne sont pas évacués ; à ce titre la minimisation de la facture énergétique d'un logement fait l'objet d'un regard particulier sous contrainte d'une tarification variable, le V2H servant de levier. Le véhicule bidirectionnel est enfin mis à contribution via une algorithmique adaptée à des fins de réglage du plan de tension et contribue ainsi au concept Vehicle-to-Grid.
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Millien, Arnaud. "Access to electricity and economic development : determinants of favorable impacts for households." Thesis, Paris 1, 2019. http://www.theses.fr/2019PA01E038/document.
Full textAbstract:
En 2018, environ un milliard de personnes vivaient sans électricité. Or l'extension des réseaux est confrontée à de nombreux défis qui compromettent la soutenabilité de l'électrification traditionnelle. Les Projets d'Electrification Décentralisée (PED) offrent désormais des solutions réalistes pour un accès à l'électricité hors réseau dans les pays en développement. Cette thèse explore le rôle de la demande de fiabilité du service d’électricité comme déterminant d’une extension durable du réseau, et l'efficacité de l'offre d’électricité décentralisée pour l’atteinte des objectifs du développement durable. Avec des données sur les coupures observées par les ménages au Kenya, le premier chapitre établit la préférence des ménages pour la fiabilité du service d'électricité, laquelle pourrait constituer le levier majeur d’une extension efficace du réseau. Dans le deuxième chapitre, une méta-analyse consolidant 112 évaluations de projets décentralisés montre que la technologie, la capacité et la gouvernance supportent les choix de conception les plus déterminants pour atteindre les objectifs du développement durable. Le troisième chapitre explore la gamme d'objectifs atteints par les pratiques de l’électrification décentralisée. Les plus efficaces sont celles qui adressent les utilisations productives et les services publics, ainsi que les micro-réseaux dans les zones éloignées, qui ont des impacts positifs sur l’information et la communication. La probabilité d'impacts positifs augmente avec la capacité des systèmes solaires individuels, qui favorisent la santé et l’éducationBy 2018, about one billion people were living without electricity. The extension of electrical grids is facing many challenges that jeopardize the sustainability of traditional electrification. Decentralized Electrification Projects (DEP) now offer feasible solutions for offgrid access to electricity in developing countries. This thesis explores the role of the demand for reliability of the electricity service as a determinant of sustainable extension of the electrical grid, and the efficiency of electricity supply by DEP to achieve the sustainable development goals. With data on outages observed by households in Kenya, the first chapter establishes the households' preference for the reliability of electricity service, which could be the major lever for effective network expansion. In the second chapter, a meta-analysis consolidating 112 decentralized project evaluations shows that technology, capacity and governance support the design choices that are most critical to achieving the sustainable development goals. The third chapter explores the range of objectives achieved by decentralized electrification practices. The most effective are those that address productive uses and public services, as well as micro-networks in remote areas, which have positive impacts on information and communication. The likelihood of positive impacts increases with the capacity of solar home systems, which favor health and education