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Active management of PV-rich low voltage networksProcopiou, Andreas January 2017 (has links)
The increased penetration of residential-scale photovoltaic (PV) systems in European-style low voltage (LV) networks (i.e., long feeders with high number of connected customers) is leading to technical issues such as voltage rise and thermal overload of the most expensive network assets (i.e., transformer, cables). As these issues significantly limit the ability of LV networks to accommodate higher PV penetrations, Distribution Network Operators (DNOs) are required to proceed with expensive and time-consuming investments in order to reinforce or replace these assets. In contrast to this traditional approach of network reinforcement, which potentially leads to massive capital expenditure, the transition towards active LV networks where controllable elements, existing (i.e., PV systems) and likely to be adopted (i.e., battery energy storage systems, LV on-load tap changer transformers), can be managed in real-time, poses an attractive alternative. Although several active network management schemes have been recently proposed to increase the hosting capacity of PV-rich LV networks, they are mostly based on managing voltage issues only; and, in general, aim to solve technical issues separately. Integrated solutions aiming at managing simultaneously voltage and thermal issues are required, as recent studies demonstrate that both issues can coexist in PV-rich LV networks. More importantly the majority of studies, which commonly neglect the characteristics of real LV networks (e.g., unbalanced, three-phase, radial, multiple feeders with several branches, different types of customers), use complex optimisation techniques that require expensive communication infrastructure and extensive or full network observability (currently not available in LV networks). However, considering the extensiveness of LV networks around the world, practical, cost-effective and scalable solutions that use limited and already available information are more likely to be adopted by the industry. Considering the above gaps in the literature, this Thesis contributes by proposing innovative and scalable active network management schemes that use limited network monitoring and communication infrastructure to actively manage (1) Residential-scale PV systems, (2) Residential-scale Battery Energy Storage (BES) systems and (3) LV on-load tap changer (OLTC)-fitted transformers. The adoption of the proposed active network management schemes, which makes use of already available devices, information and requires limited monitoring (i.e., secondary distribution substation), allows making the transition towards active LV networks more practical and cost-effective. In addition, to tackle the challenges related to this research (i.e., lack of realistic LV network modelling with high resolution time-series analyses), this Thesis, being part of the industrial project 'Active Management of LV Networks' (funded by EDF R&D) and having access to French data, contributes by considering a fully modelled typical real residential French LV network (three-phase four-wire) with different characteristics and number of customers. Moreover, realistic (1-min resolution) daily time-series household (from real smart meter data) and PV generation profiles are considered while a stochastic approach (i.e., Monte Carlo) is adopted to cater for the uncertainties related to household demand as well as PV generation and location.
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Sustainability-Efficiency Paradox: The Efficacy of State Energy Plans in Building a More Sustainable Energy FutureZimmerman, Austin 01 January 2018 (has links)
State energy plans are created at the request of a sitting governor or State Legislature in order to provide guidance set goals for the state’s energy sector. These plans will be critical indicators of energy trends such as the future market share of coal, natural gas, and renewables. If the future of energy in the United States is to be remotely sustainable, low-carbon policies must headline state plans. The strength of a state’s energy plan in terms of sustainability is directly related to that state’s willingness to prioritize and commit to incorporating energy sources that produce negligible carbon emissions. Questions about the role of efficiency can be answered by the political need for short-run payoffs that do not necessarily align with the long-term goals of sustainability (Kern & Smith, 2008). The nature of the American political system is that representatives want to be able to bring immediate results to their constituents, results that are usually shown in the short-run by efficiency programs. While the state energy plans in question (California, Arizona, Pennsylvania, Iowa, South Carolina, and Virginia) engage with sustainability at varying levels of strength, they deal mostly in weak sustainability by failing to commit to renewables. Historical reliance on energy efficiency and its accompanying theories of growth has created a climate in which state energy plans do not generally realize their enormous potential to lead the national transition away from fossil fuels.
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Energetická politika SRN a Spojeného království v kontextu jejich klimatických závazků / Germany's and the UK's Energy Policy in the Context of Their Climate PledgesŠulcová, Kristýna January 2019 (has links)
The main focus of the present diploma thesis are the energy policies of Germany and the United Kingdom. In the thesis, a comparative analysis of both countries' policies is carried out, focusing on their progress towards a low carbon energy sector and on the fullfillment of their respective climate pledges, such as the share of renewable sources of electricity and total emissions. The scope of the thesis is narrowed down to include above all the electricity sector and the technologies that help to reduce the energy intensity of the energy sector. The central part of the text is descriptive, comparing both the general outlines of the respective policies and the policy instruments used. The thesis largely follows the logic of comparing the different approaches to the main energy sources (nuclear, renewable, natural gas) and in part also deals with other important phenomena: CCS and EU ETS. The choice of relevant indicators and the evaluation of trends is an integral part of the thesis. The secondary goal is to attempt an evaluation of the individual instruments and policies. Among the conclusions, the following stands out: 1/ the relative success of the German nuclear phaseout as concerns supply security and the simultaneous risks it brings concerning the total emissions from energy; 2/ the relative...
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Modeling and comparative analysis of different grid-forming converter control concepts for very low inertia systemsWestman, Martin, Nordén, Ellen January 2020 (has links)
As renewable power from DC sources are constantly increasing their power generation share compared to the high inertia generators that provide robustness to the grid, the overall stability of the grid decreases. Grid forming converter could be the solution to this problem. This thesis includes a pre-study of grid forming control methods, implementation of the most promising and relevant methods in a generic PSCAD modeling environment for comparative analysis and for establishing pros and cons. Lastly, studying the system impact of each grid forming control method through small-signal stability and fault analysis. Four methods of grid forming were implemented and evaluated during the course of the thesis, which were: Droop control, Virtual Synchronous Generator control, Power Synchronization control and Synchronous Power control. All methods fulfilled the criteria for successful implementation with good results. For further developments, we would recommend Synchronous Power control and Virtual Synchronous Generator control for their development potential and operational width.
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Market Acceptance of Renewable Energy Technologies for Power GenerationElizabeth A Wachs (9181997) 29 July 2020 (has links)
The perception of climate change as an emergency has provided the primary impetus to a transition from conventional fossil-based energy sources to renewables. The use of renewable energy sources is essential to sustainable development, since it is the only way that quality of life can remain high while greenhouse gas emissions are cut. Still, at the time of writing, renewables contribute a small part of the total primary energy use worldwide. Much research has gone into understanding barriers to the full-scale adoption of renewable energy sources. Still, many of the tools used have focused primarily on optimal paths, which are useful in the long-term but problematic in non-equilibrium markets. In the shorter term, behavior is thought to be more governed by existing institutions and commitments until those frameworks can be changed. This means that understanding people's attitudes towards renewables is key towards understanding how adoption will take place and how best to incentivize such action. Particularly, decisions are made by investors, who serve as intermediaries between what customers/public want and the existing institutions (what is possible). Understanding their responses to the current state of affairs as well as perturbations in the form of policy changes is important in order to effect change or make sure that policies will work as intended. <br> <br> First, the shifting demand landscape is considered, specifically in Indiana cities. Heating is shrinking as a driver of primary energy use over time due to climate change, while transport increases relatively. Electricity demand continues to increase, and the potential for electrification of transport can add to this potential. This led to a focus on the electricity sector for further work. Noticing that adoption lags public support led to a comparison of levelized cost of electricity and net present value metrics for 18 dominant technologies in two power markets in the US. Capacity markets and solar renewable energy credits lead to differences between cost and net present value in PJM, making natural gas the most attractive technology there. Noting the difference in electricity price between the two markets also provides a caution regarding the employment of carbon pricing in PJM, since that is an additional cost to the consumer who is already paying twice to fossil based generation in that region, once for energy provision and once for reliability. <br> <br> Individual technologies represent only part of the question, however, since generation capacity is added to bolster existing supplies. In order to study the portfolio, historical risk is considered along with levelized costs to identify optimal portfolios in CAISO and PJM. Then electricity is treated as a social good, and a sustainability profile was built for each technology balancing current equity and risks to future generations. This allowed quantification and identification of barriers to market acceptance of renewables, but it also led to a recognition of where useful metrics are still lacking. For example the use of land provides an important barrier to the adoption of renewables, and is a potent potential barrier for future acceptance. It is not well understood, however, which led to a critical review of existing technologies. <br> <br> The work in this dissertation provides one of the first mixed methods attempts to assess energy demand for cities including the end use of cooling. It provides a simple model that demonstrates the importance of capacity markets in determining the profitability of different energy technologies. It provides a guide to the emerging issue of land use by energy systems, a key consideration for the study of the food-energy-water nexus. It is the first use of portfolio optimization for sustainability studies. This is an important methodological tool since it allows a comprehensive sustainability analysis while providing a sense of the difference between immediate and future risks. The tool also allows users to diagnose which technologies are incentivized and which are deterred by market factors, as well as the strength of the deterrence. This is helpful for policy makers in understanding how incentives should be structured.
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Gulf Cooperation Council (GCC) countries 2040 energy scenario for electricity generation and water desalination.Almulla, Youssef January 2015 (has links)
Judicious modeling of an energy system can help provide insights as to how elements of the energy system might be configured in the longer term. The current and future electricity and water desalination systems of each GCC country were represented using a full-cost based optimization tool called MESSAGE and the following scenarios were examined: 1. The business as usual scenario (BAU): current energy system is extended into the future without any changes. The energy system structure and characteristics are kept the same. The fuel prices are also kept at the current subsidized levels. 2 - The netback-pricing scenario: all fuel costs are increased to the international market price. The freed amount of fuel is assumed to be available for export to the international market. Moreover, this scenario examines different carbon tax options of 0, 20,30 ,40 and 50 dollars per kilo tons of CO2 emissions. 3 - The Nuclear hub scenario: examines the idea of a “nuclear hub” state for the GCC region that can have all the “know-how” and logistics to provide sufficient nuclear energy for the GCC through the Interconnection Grid “GCCIG”. Results shows that fossil fuels will continue to play an important role in a least cost future for the region. This is due, in no small part, to the cheap natural gas resources in the GCC. Despite the high renewable energy technologies potential, their penetration – given the study assumptions - proved to be important, but limited in the GCC. On the other hand, nuclear energy shows clear economic potential.
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Competitive Strategy for Entering Wind Turbine Manufacturing IndustryKAUTS, MAREK-ANDRES January 2015 (has links)
The purpose of this thesis is to explore, how it is best to enter to the wind turbine manufacturingindustry and suggest a competitive strategy for that purpose.The thesis follows Michael E. Porter's Competitive Strategy framework. The market is analyzed using data and scenarios from World Energy Council, Global Wind Energy Council and European Wind Energy Association. As competitors, European-based wind turbine manufacturers belonging by their market share to Global Top 10 are analyzed. A five-point competitive strategy is drafted.Technological innovations and business model improvements are not analyzed in this thesis.The result of competitive strategy research performed in this thesis is, that a window to enter to wind turbine manufacturing industry is embedded into the process of establishing a new experience curve. The new experience curve is based on direct drive wind turbine concept. The thesis suggests that the market to enter the industry is European onshore wind turbine market.A major barrier entering the industry is well established relationships between old wind turbine manufacturers and customers whereas the newcomers lack of sufficient references. A strategy to hurdle the barrier is acquiring the references by forward integration. Therefore, to enter to the market, wind turbine company should own its own wind park as a base of references and new product testing. As wind parks product, electricity is a commodity and sold on a commodities market, the forward integration does not need major extra know how.Core competences for the emerging company include product engineering and quality management.
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The European Energy transition and its impact on EU energy politics. : A comparison of France and Germany in their discursive struggle.Okur, Elias January 2024 (has links)
As part of its initiative to decarbonise the energy grid, the European energy transition towards alternative energies presents a relevant field of inquiry within energy politics. This study delves into the discursive contestations between France and Germany about the energy transition, examining their influence on EU-wide approaches. Debates encompassing nuclear power's role and technological sovereignty considerations are central to the analysis. Germany’s focus on renewables contrasts France’s reliance on atomic energy as a low-carbon solution. Moreover, the discourse extends to the necessity of a cohesive European strategy for the energy transition, especially in response to global economic dynamics and the intention of achieving carbon neutrality. Furthermore, the study explores the socio-economic impacts of the transition, with both countries striving to support their industries while ensuring competitive electricity pricing. It is manifested through initiatives such as the Electricity Market Reform (EMR) and the Renewable Energy Directive (RED). The discussions are analysed through a constructivist lens, employing a discursive institutionalist method, examining the institutional context through ideas, agents and discursive interactions leading to collective actions. The thesis concluded that France’s greater assertiveness in debates around the RED III and the EMR secured the importance of nuclear power in the EU’s future energy transition efforts.
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Urban Microgrid Design : Case Study of a Neighborhood in LisbonRodrigues, João January 2018 (has links)
Urban microgrids are smart and complex energy systems that help integrate renewables into our cities, turning our neighborhoods into partly energy self-sufficient hubs. Moreover, they create the space for electricity transactions between neighbors, transforming the former consumers into prosumers. The following work proposes the implementation of an urban microgrid to a neighborhood in Lisbon, Portugal. This dissertation’s objective is designing and discovering the optimal photovoltaic and storage capacity, optimal electricity dispatch, effects of distributed energy production in grid voltage and economic viability of such a system. With this purpose, a comprehensive model was elaborated, considering specific site weather data, electric loads, grid topology and utility tariffs. The self-sufficiency of Arco do Cego was found to be 66% in this study, reducing its carbon footprint by 61%. A detailed map of where to place each PV system and battery bank was generated, with specific electricity dispatch strategies. Moreover, the system was designed under real grid voltage, current and power flow constraints.
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Gas for Balancing of Variable Power Generation : A Systemic Case Study / Gas för balansering av varierande elproduktionBortot, Baptiste January 2014 (has links)
With the increasing share of variable renewable generation, balancing electric powersystems could become a major concern for system operators because of their variableand hardly predictable nature. However, gas technologies appear as a solutionto provide this flexibility, but the impacts on the gas power system have hardly beeninvestigated. In this thesis, consulting reports on the subject matter, regulator suggestions andgas-electricity interaction models in scientific literature are studied and four sourcesare identified to be used for balancing: linepack, storage facilities, liquefied natural gasand intraday gas supply from adjacent areas. Then, a gas-electricity model for flexibility supply is designed and three case studies are simulated in order to analyze bothgas and electric power systems’ behaviors. In these case studies, electricity generation,contribution of gas sources and costs are analysed. The study concludes that critical situations on gas market that can occur, e.g. incases of large variation in the net electricity demand and limited availability of linepackand storage facilities, the need of intraday modulation can exceed the possibilities toprovide for it. Then, gas cannot be supplied to power plants during peak periods, andmore gas than necessary is used during off-peak periods. The case studies also showthat day-ahead forecast errors in variable renewable generation can be handled mucheasier than variations by the gas system but leads to higher costs.
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