Dissertations / Theses on the topic 'Renewable energy sources'
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Romaniuk, O. "Renewable energy sources." Thesis, Видавництво СумДУ, 2009. http://essuir.sumdu.edu.ua/handle/123456789/13666.
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Kondratyuk, O. V. "Renewable energy sources in Ukraine." Thesis, Видавництво СумДУ, 2009. http://essuir.sumdu.edu.ua/handle/123456789/13612.
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Malý, Jan. "Renewable Energy Sources Support Policy." Master's thesis, Vysoká škola ekonomická v Praze, 2009. http://www.nusl.cz/ntk/nusl-11041.
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Renewable energy sources support policy employs a great variety of economic tools in order to promote the use of green energy. Following thesis at first offers an overview and economic insight into the most applied ones. Since the majority of the European Union Member States nowadays prefer so-called feed-in tariffs schemes we proceed in-depth analysis of effectiveness of that instrument in electricity sector in four selected European countries Austria, Czech Republic, Germany and Spain. An effectiveness indicator which compares marginal electricity generation potential with additional realizable potential of particular renewable energy sources technology is used for that analysis. The results clearly show that the best practice of feed-in tariff design is pursued in Germany where the special set of tariff design and adjustment measures is applied.
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Johnson, Darrin B. "Federal renewable-energy research and development funding and innovation /." View online, 2008. http://repository.eiu.edu/theses/docs/32211131423535.pdf.
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Ashby, Scott John. "Remaining off-line : an investigation of Australia's reaction to renewable energy technology development /." Title page, table of contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09ENV/09enva823.pdf.
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Yan, Zuanhong. "Control of fluctuating renewable energy sources : energy quality & energy filters." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8568/.
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This doctoral study discusses how to control fluctuating renewable energy sources at converter, unit, and system layers to deliver smoothed power output to the grid. This is particularly relevant to renewable power generation since the output power of many kinds of renewable energy sources have huge fluctuations (e.g. solar, wind and wave) that needs to be properly treated for grid integration. In this research, the energy quality is developed to describe the friendliness and compatibility of power flows/waveforms to the grid, by contrast with the well-known concept of power quality which is used to assess the voltage and current waveforms. In Chapter 1 & 2, a background introduction and a literature review of studied subjects are presented, respectively. In Chapter 3, the problem of determining the PI parameters in dq decoupling control of voltage source converter (VSC) is studied based on a state-space model. The problems of the conventional method when there is insufficient interface resistance are addressed. New methods are proposed to overcome these drawbacks. In Chapter 4 & 5, energy quality and the energy filters (EFs) are proposed as tools to assess and manage power fluctuations of renewable energy sources. The proposed EFs are energy storage control systems that could be implemented on a variety of energy storage hardware. EFs behave like low-pass filters to the power flows. Finally, in Chapter 6, as an application example of renewable power plant with energy filter control and smoothed power output, a master-slave wave farm system is proposed. The wave farm system uses enlarged rotor inertia of electric machines as self-energy storage devices.
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Griffin, James. "Improving cost-effectiveness and mitigating risks of renewable energy requirements." Santa Monica, CA : RAND, 2008. http://www.rand.org/pubs/rgs_dissertations/2008/RAND_RGSD236.pdf.
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Thesis (Ph.D.)--RAND Graduate School, 2008.Title from title screen (viewed on Oct. 24, 2008). "This document was submitted as a dissertation in September 2008 in partial fulfillment of the requirements of the doctoral degree in public policy analysis at the Pardee RAND Graduate School." --T.p. Includes bibliographical references: p. 168-178.
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Mendes, Barlach Leonardo. "Dynamic modelling of variable renewable energy generation sources." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/112066.
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Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (page 56).
Renewable energy is one of the most important technologies for decarbonizing the economy and fighting climate change. In recent years, wind energy has become cheaper and more widely adopted. However, the variable nature of wind production creates unique challenges that are not faced by conventional thermal technologies. Several studies to date have showed the decrease in economic value of wind energy as penetration increases due to this variable nature. Plus, they also show that high wind penetration favors intermediate energy sources such as natural gas. I claim however, that few of these studies have considered the dynamic behavior and feedbacks of these systems, including investment delays and learning curves. This thesis uses system dynamics models to simulate the long term changes in the electric grid for Texas. The goal is to test two hypothesis: that the economic value of wind energy decreases as penetration increases, and that variable wind production favors natural gas technologies. It does this by calculating how wind energy changes the shape of the net load duration curve for a given region. This affect changes the profitability of different technologies in unique ways, due to their different fix and variable costs. The conclusions of this thesis are consistent with the literature, with the caveat that they are highly dependent on assumptions regarding the learning curve for energy technologies. The economic value of wind decreases, but this effect can be compensated by lower costs, leading to a continuing adaptation. Faster Wind adoption also reduces the profitably of technologies with high fixed costs such as coal and nuclear, and favors intermediate and peaking sources such as natural gas.
by Leonardo Mendes Barlach.
S.M. in Engineering and Management
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Jhala, Kumarsinh. "Coordinated electric vehicle charging with renewable energy sources." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/19767.
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Master of ScienceDepartment of Electrical and Computer Engineering
Balasubramaniam Natarajan
Anil Pahwa
Electric vehicles (EVs) are becoming increasingly popular because of their low operating costs and environmentally friendly operation. However, the anticipated increase of EV usage and increased use of renewable energy sources and smart storage devices for EV charging presents opportunities as well as challenges. Time-varying electricity pricing and day-ahead power commitment adds another dimension to this problem. This thesis, describes development of coordinated EV charging strategies for renewable energy-powered charging stations at homes and parking lots. We develop an optimal control theory-based charging strategy that minimizes power drawn from the electricity grid while utilizing maximum energy from renewable energy sources. Specifically, we derive a centralized iterative control approach in which charging rates of EVs are optimized one at a time. We also propose an algorithm that maximizes profits for parking lot operators by advantageously utilizing time-varying electricity pricing while satisfying system constraints. We propose a linear programming-based strategy for EV charging, and we specifically derive a centralized linear program that minimizes charging costs for parking lot operators while satisfying customer demand in available time. Then we model EV charging behavior of Active Consumers. We develop a real-time pricing scheme that results in favorable load profile for electric utility by influencing EV charging behavior of Active Consumers. We develop this pricing scheme as a game between electric utility and Active Consumers, in which the electric utilities decide optimal electricity prices that minimize peak-to-average load ratio and Active Consumers decide optimal charging strategy that minimizes EV charging costs for Active Consumers.
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Nielsen, Knut Erik. "Superconducting magnetic energy storage in power systems with renewable energy sources." Thesis, Norwegian University of Science and Technology, Department of Electrical Power Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-10817.
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The increasing focus on large scale integration of new renewable energy sources like wind power and wave power introduces the need for energy storage. Superconducting Magnetic Energy Storage (SMES) is a promising alternative for active power compensation. Having high efficiency, very fast response time and high power capability it is ideal for levelling fast fluctuations. This thesis investigates the feasibility of a current source converter as a power conditioning system for SMES applications. The current source converter is compared with the voltage source converter solution from the project thesis. A control system is developed for the converter. The modulation technique is also investigated. The SMES is connected in shunt with an induction generator, and is facing a stiff network. The objective of the SMES is to compensate for power fluctuations from the induction generator due to variations in wind speed. The converter is controlled by a PI-regulator and a current compensation technique deduced from abc-theory. Simulations on the system are carried out using the software PSIM. The simulations have proved that the SMES works as both an active and reactive power compensator and smoothes power delivery to the grid. The converter does however not seem like an optimum solution at the moment. High harmonic distortion of the output currents is the main reason for this. However this system might be interesting for low power applications like wave power. I
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Kiljanov, Grigory. "Accumulation of energy in autonomous power plants using renewable energy sources." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264272.
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Kiljanov G.M. Energy storage in autonomous power plants using renewable energy sources, 2017 - p.104, 11 tables, 40 pic. Head Bessel V.V., Professor, Ph.D. Department of Thermodynamics and Thermal Engines. An analysis of existing energy storage devices in the world is carried out. The scientific and technical basis of energy storage. The device and the operating principle of an autonomous combined power plant with an energy storage device are considered. On the basis of the technological calculation, an optimal combination of a wind generator, a system of solar panels and a reservoir, which can provide reliable and uninterrupted power generation, was chosen. The economic efficiency of the project on the use of combined medium power plants at gas production facilities in remote areas was estimated. Conclusions are drawn about the advisability of introducing energy systems based on renewable sources with energy storage devices at the country's enterprises.Kilyanov G.M. Energilagring i autonoma kraftverk som använder förnybara energikällor, 2017 - s.105, 11 tabeller, 40 bild. Chef Bessel V.V., professor, Ph.D. Institutionen för termodynamik och termiska motorer. En analys av befintliga energilagringsenheter i världen utförs. Den vetenskapliga och tekniska grunden för energilagring. Enheten och driftsprincipen för ett autonomt kombinerat kraftverk med en energilagringsanordning beaktas. Baserat på den tekniska beräkningen valdes en optimal kombination av en vindgenerator, ett system av solpaneler och en reservoar, som kan ge pålitlig och oavbruten elproduktion. Projektets ekonomiska effektivitet på användningen av kombinerade medelkraftverk vid gasproduktionsanläggningar i avlägsna områden uppskattades. Slutsatser dras om att det är lämpligt att införa energisystem baserade på förnyelsebara källor med energilagringsenheter hos landets företag.
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Peker, Zeynep Süel Akın. "Integrating renewable energy technologies into cities through urban planning: In the case of geothermal and wind energy/." [s.l.]: [s.n.], 2005. http://library.iyte.edu.tr/tezler/doktora/sehirplanlama/T000428.pdf.
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Sakib, Nazmus. "Effects of incorporating renewable energy sources into the electricity grid." Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53485.
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With the increasing demand for energy throughout the world, the environment around us is getting severely affected. The conventional energy sources (coal, oil and gas) are unfortunately the biggest polluters of the environment. The aforementioned energy sources emit greenhouse gases like carbon dioxide and methane, which are responsible for global warming and ozone layer depletion.
The only feasible answer to this problem is to reduce the use of the conventional energy sources and focus more on other energy sources. The renewable energy sources (solar, wind and hydro) have been present in nature, but the technology to harvest these energies have always been relatively expensive until recently. The biggest advantage of using renewable energy sources is the fact that these energy sources will never run out and they also do not pollute the environment as their more conventional counterparts.
With more research being conducted into better ways of storing the power trapped from the renewable energy sources and the relative difficulty of obtaining the ever-depleting conventional energy sources, the future for renewable energy sources definitely looks better than at any time in the past
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Aljaism, Wadah A., University of Western Sydney, and School of Engineering and Industrial Design. "Control method for renewable energy generators." THESIS_XXX_EID_Aljaism_W.xml, 2002. http://handle.uws.edu.au:8081/1959.7/796.
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This thesis presents a study on the design method to optimise the performance for producing green power from multiple renewable energy generators. The design method is presented through PLC (Programmable Logic Controller) theory. All the digital and analogue inputs are connected to the input cards. According to different operations conditions for each generator, the PLC will image all the inputs and outputs, from these images; a software program has been built to create a control method for multiple renewable energy generators to optimise production of green power. A control voltage will supply the output contractor from each generator via an interface relay. Three renewable generators (wind, solar, battery bank) have been used in the model system and the fourth generator is the back up diesel generator. The priority is for the wind generator due to availability of wind 24 hours a day, then solar, battery bank, and LPG or Diesel generators. Interlocking between the operations of the four contractors has been built to prevent interface between them. Change over between contractors, according to the generator's change over has also been built, so that it will delay supplying the main bus bar to prevent sudden supply to the load. Further study for controlling multiple renewable energy generators for different conditions such as controlling the multi-renewable energy generators from remote, or supplying weather forecast data from bureau of meteorology to the PLC directly as recommended.Master of Electrical Engineering (Hons)
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Mok, Hei-lun Allen. "An education and research centre on renewable energy." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B25947205.
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Ninikas, Konstantinos. "Opportunities for renewable heat energy from shallow geothermal sources." Thesis, Glasgow Caledonian University, 2017. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.726798.
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Shendryk, S. O. "Decision support in managment of hybrid renewable energy sources." Thesis, Sumy State University, 2017. http://essuir.sumdu.edu.ua/handle/123456789/65232.
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Nowadays the distributed energy generation and renewable energy sources (RES) are the main areas of energy development all over the world. They play a significant role in improving the reliability and quality of the supplied electricity. Various forms of RESs using solar and wind energy are also proposed.
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Zenkert, Patrik, and Douglas Lowén. "Automatic control of renewable energy sources at varying load." Thesis, Uppsala universitet, Elektricitetslära, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-415098.
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With the current climate crisis with the global temperature increasing due to fossil fuels being used there are big investments in green energy. Wind power is a good alternative to fossil fueled power and already has a widespread use. One of the problems with wind poweris control and keeping the grid frequency stable during peaks and lows of power generation. In this master thesis there is a goal to implement a system which can regulate wind mills while always trying to use as much wind power as possible. A model was built in Matlab to represent the final product which was translated into a SCADA system. A fully integrated communication from SCADA computer to PLC to IED to wind mill and back was built. The simulation in the SCADA system gave satisfactory result where the wind power wasutilized to the maximum, and other conditions met. The laboratory experiment with an Arduino represented as the wind mill lacked in communication and the model did not achieveperfect results in every case. There is future work to be done, improved communication, additional or alternative automatic control and creating a bigger system with several powerproducers integrated.
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Aldaoudeyeh, Al Motasem. "Weak Power Grid Analysis for Renewable Energy Sources Integration." Diss., North Dakota State University, 2019. https://hdl.handle.net/10365/31536.
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Weakness analysis based on grid strength assessment is useful for identifying potential weak grid issues. However, when taking into account the impact of the interactions among Renewable Energy Sources (RESs), the weakness analysis becomes computationally challenging. Different combinations of PointsofInterconnections (POIs) of RESs may have different impacts on grid strength at each POI. Due to the combination nature, such weakness analysis may be time-consuming when identifying the weakest combination of POIs from a large number of potential candidate locations in realistic power grids. This dissertation addresses the topic of determination of the weakest RESs combinations. Based on impedance ratios as a criterion, the dissertation shows that the impacts of impedance ratios magnitudes and angles are ?quasi-mutually exclusive?. Such a concept is then used to reduce the computational burden with a fast screening algorithm.
To further understand the impact of network components on grid strength, vector-based interaction analysis is developed based on the concepts of operational transfer impedances and operational interaction operators. In particular, this dissertation shows how mathematical models of interaction of multiple RESs can be simplified by replacing them with equivalent impedances, allowing us to simplify the mathematical expressions that quantify interactions among RESs. The conclusions and concepts established based on simplified models are statistically tested for their applicability to the generalized interaction model. The result would be a more simplified mathematical representation of interaction among RESs.
Finally, a new technique is presented to efficiently update the Bus Impedance Matrix (Zbus) following changes in the series impedance of a branch. Conventionally, such update requires redundant recalculations, which involve matrix inversion operations (i.e., inverting the Bus Admittance Matrix, Ybus) and thus cause high computational burden because of potential matrix ill-conditioning, especially for largescale power grids. This dissertation overcomes these shortcomings by deriving an analytical expression for changes in Zbus in terms of its old elements and the variation of the impedance of a given branch. Hence, the computation overhead is comparatively small, and no issues arise due to the new Ybus being ill-conditioned. Such contribution helps facilitate real-time applications of methods that rely on Zbus.
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Folliero, Maria Gelsomina. "Energy Production and Storage from Renewable Sources through Electrocatalysis." Doctoral thesis, Università di Siena, 2018. http://hdl.handle.net/11365/1042757.
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The energy transition from fossil fuels to renewables will be a long and difficult process but it is not avoidable since fossil sources depletion, pollution and geopolitical situations are becoming worrisome. There are different challenges for researchers in the field of energy. From renewable energy production data it is clear the remarkable growth of solar electricity technologies, that crystalline silicon photovoltaics (PV) and wind turbines are the workhorses of the first wave of renewable energy deployment around the globe. Anyway these renewable energy are not equally distributed and, for their natural discontinuity, cannot sustain the requirements of our society. In this perspective the energy storage will play a fundamental role in the development of an energy system based on renewable sources.
The storage of hydrogen as gas in pressured tanks poses many problems, in particular for transport safety concerns. The alternative is the production on demand of this gas by using storing hydrogen materials. These materials can help developing mobility systems based on hydrogen as fuel, since the reserve of hydrogen would be stored as a solution, for example of sodium borohydride.
The interconversion between electricity and hydrogen and biofuels, like bioethanol, could be the keystone of a new sustainable energy economy. The development of two electrochemical devices can serve to this energy system, fuel cells and electrolyzers. Fuel cells are devices that can convert cleanly chemical energy stored in hydrogen or bioalcohols into electrical energy, while electrolyzers use electrical energy to produce molecules, which can be energy vectors such as hydrogen.
The electrical energy surplus could be used in another kind of electrolyzers, for example for the reduction of CO2. In these devices it’s possible to obtain different products but the performance of electrocatalysts at the moment are not so good to make this electroreduction particularly appealing due to high energy costs, low activity and stability of the catalysts.
The focus on this thesis is to face the energy problems by different points of view: 1) the production of electrical energy from renewable resources with Direct Liquid Fuel Cells (DLFCs), 2) the production of hydrogen from storage materials and from electrolysis, 3) the storage of electrical energy producing useful molecules in electrolyzers.
During the three years catalysts have been synthesized and characterized for their morphology and activity, both in electrochemical half-cell and complete cell systems or in properly designed reactors.
In Chapter 1 a description of the state of the art of fuel cells and electrolyzers is provided and describes the advantages in replacing the traditional proton exchange membrane electrolytes with anion exchange membranes. In Chapter 2 an introduction of the electrochemical reduction of CO2 is given, focusing on copper and palladium as electrode for this reaction.
The discussion of the results will be divided in three main Chapters,(3,4,5).
The first one, Chapter 3, is on Direct Liquid Fuel Cells. The electrocatalysts employed are nanostructured Pd at the anode and Fe-Co at the cathode. The performance of microscale direct ethanol fuel cells (DEFCs) was studied with an equipment of a membrane electrode assembly (MEA) of 1 cm2 size with four anion exchange membranes. A fuel concentration of 6 M ethanol+6 M KOH was chosen to test the stability at a constant current density of 1 mA cm−2. The cell ran for 87 days with a potential drop of 3 mV day−1, and the energy delivered was 1.08 Wh. Furthermore, in order to explore functioning in conditions that maximize delivered energy density, a direct formate fuel cell (DFFC) operating at different formate and alkali concentrations has been investigated. The active DFFC at 60 °C with 4 M HCOOK + 4 M KOH as anode fuel and O2fed to the cathode produces a maximum power density of 258 mA cm−2.
In Chapter 4, for the production of hydrogen the design and construction of a reactor for sodium borohydride (SBH) hydrolysis and the performance of palladium and rhodium based electrocatalysts in a electrochemical reformer are presented. For SBH hydrolysis a cobalt boride (CoxB) catalyst supported on a commercial Cordierite Honeycomb Monolith (CHM) was used. The electrooxidation performances of Pd/C and Rh/C catalysts were studied at different temperature with different organic molecules as substrates. In particular, Pd/C with formate, exhibits an onset of 200 mV and a specific activity of 2100 A g−1Pd; while Rh/C has an excellent activity for methanol oxidation, showing an onset potential 200 mV lower than Pd/C and a specific activity almost double reaching the value of 2600 A g−1Rh. In addition examples of electrooxidation of biomass-derived alcohols such as EtOH, EG, G and 1,2-P have been studied in an electroreformer containing Rh nanoparticles supported on carbon as the anode electrocatalyst, equipped with an anion exchange membrane and a Pt/C on carbon cloth cathode. The oxidation of alcohols was investigated in electrochemical half-cells at room temperature and at 60–80 °C in alkaline media. The results highlighted the excellent activity of Rh/C in terms of peak current densities (as high as 5700 A gRh-1 for EG at 80 °C) and low onset of potentials.
Copper and Palladium based catalysts, studied for the electroreduction of CO2, are reported in Chapter 5. To enhance the activity of these two metals for CO2RR, two different paths were followed: 1) copper surface and morphology were modified to vary the products compositions and enhance activity; 2) palladium was alloyed with a different metal, gold, to improve performance and stability. The surface modification on copper resulted in an enhancement of the surface area of a copper foil and influenced the selectivity of the reduction reaction products. The Au-Pd alloy nanoparticles have shown high activity and selectivity for the electroreduction of CO2, where CO was the only product of the electrocatalysis.
In the Chapter 6 there are conclusions and considerations on the whole work during the three years. The importance of the nanostructured catalyst is evident in every application described in this work. These materials showed improved performance and their applications can really represent a turning point in the energy field.
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Sirca, Silvia <1992>. "Chinese Investments in Italy in energy from renewable sources." Master's Degree Thesis, Università Ca' Foscari Venezia, 2018. http://hdl.handle.net/10579/13880.
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In recent years Chinese presence in Italian market has grown at a very fast pace, becoming an important player in Italian economy. Quantify the dimension of these investments is one of the most common questions asked by economists, politicians and public opinion in general. A complete, exhaustive analysis on the dimension of investments in Italy is impossible for several reasons. The first is the dimension itself of such investments, being very big, and second, they are in many sectors in all the country. Furthermore, a database on these investments does not exist. It is quite impossible to define exactly how much money China invested in Italy. Write off a document identifying the dimension of Chinese investments in Italy is not the aim of this work. In this work the focus has been put on just one sector in which Chinese companies invested, the production of Energy from renewable sources. Starting from this point I analyzed the companies in Italy financed by Chinese investors, their dimension, revenues and profitability, and compared the results with companies in the same sector, similar for dimension and revenues to see if there were similarities also in profitability. The analysis is not just limited to the profitability of the Chinese run companies, but attention has also been put on the Chinese parent companies, analyzing their business in China and in the rest of the world, to better understand the reasons beside the choice to invest in Italy.
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Homon, Bohdan. "Combined power supply system converting unit with renewable sources." Thesis, Дніпропетровський національний університет залізничного транспорту ім. академіка В. Лазаряна, 2017. https://er.knutd.edu.ua/handle/123456789/9329.
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The article deals with the implementation of renewable energy sources in local electrical systems such as solar battery, wind turbines. The improvement and wide spread of the sources of distributed generation renewable energy sources is one of the ways to improve the energy security of the country.Стаття присвячена питанню впровадження відновлювальних джерел енергії (сонячна батарея, вітрові турбіни) в місцевих електричних системах. Покращення та широке розповсюдження поновлюваних джерел енергії розподіленої генерації є одним із способів підвищення енергетичної безпеки країни.
Статья посвящена вопросу внедрения возобновляемых источников энергии (солнечная батарея, ветровые турбины) в местных электрических системах. Улучшение и широкое распространение возобновляемых источников энергии распределенной генерации является одним из способов повышения энергетической безопасности страны.
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Guduru, Giridhar Reddy. "Management of energy and power using renewable energy sources based on ZigBee." Thesis, California State University, Long Beach, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10004167.
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The energy and power used at various areas like households and industries is increasing gradually due to many reasons and there is a need to sustain it. This project introduces a method to reduce the energy used in a household by considering the energy sources and the amount of energy used by the appliances concurrently. Modules are used to measure and check the energy utilized by the appliances using ZigBee. Energy is generated on a conventional basis using three sources: solar panel, wind mill and conventional power. An inverter and a battery are used to connect these sources to a grid. When a device is connected, the units of power consumed are computed and shown on the LCD using LPC2148 microcontroller. The output of the battery is connected to the controller, which shows the voltage of the battery and also selects the best source to be used. Modules use a 5V supply and the controller uses 3.3V power supply. Voltage is controlled with the help of a 7805 voltage regulator and the output of transformer is revised by a rectifier.
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Shvets, O. "The influence of renewable energy sources on the prospects of nuclear energy." Thesis, Київський національний університет технологій та дизайну, 2018. https://er.knutd.edu.ua/handle/123456789/10804.
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Ahmed, Rana. "Energy management and control for hybrid renewable energy sources in rural area." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4353.
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Cette thèse propose principalement, un algorithme État-Flow MPPT basé P&O, amélioré avec deux degrés de liberté, dans lequel le système événementiel (MPPT) de comportement est modélisé par le décrivant en terme de transition entre les états, sous certaines conditions. Secondairement, un algorithme étendu MPPT, base d'exploitation en parallèle de l'état-débit est en outre proposé d'être une solution difficile pour le contrôle indépendant du système hybride, où la caractéristique de contrôle continu peut se présenter au cours d'un certain état de travail tout en discrète, est indiquée le long des transitions d'état. Deux configurations possibles pour le système hybride sont proposées : deux convertisseurs DC/DC séparés, et un convertisseur de sortie unique à double entrée (DISO) de configurations. Enfin, il est proposé, un comportement du système DC modélisation utilisant État-Flow, menant à l'ensemble de la conception de la stratégie de commande qui concernent RES MPPT, RES et la coordination BESS, la stabilité du système d'alimentation et de régulation de la tension du bus DC. La simulation et les résultats expérimentaux valident l'efficacité et l'applicabilité de l'algorithme proposé. Les deux résultats montrent la supériorité du MPPT basé proposé État-Flow pour réduire les oscillations de puissance RESs à l'état d'équilibre dans diverses conditions d'exploitation, en plus de son démarrage plus rapide, et l’opération de transition sans divergence de la MPP, selon des conditions météorologiques variablesThis thesis primarily proposes, an improved P&O based State-Flow MPPT algorithm featuring two degree of freedom, in which the event driven system (MPPT) behaviour is modelled by describing it in terms of transitions among states under certain conditions. Secondarily, an extended parallel operating State-Flowbased MPPT algorithm is further proposed to be a challenging solution for the independent control of the hybrid system, where continuous control characteristic can present during a certain working state while discrete one is indicated along state transitions. Two possible configurations for the hybrid system are proposed; two separate DC/DC converters and dual input single output converter (DISO) configurations. Finally it is proposed, DC system behaviour modelling using State-Flow leading to the whole control strategy design which concern RESs MPPT, RESs and BESS coordination, power system stability and DC bus voltage regulation.Simulation and experimental results validate the effectiveness and applicability of the proposed algorithm, both results show the superiority of the proposed State-Flow based MPPT in reducing the RESs power oscillations at steady-state in various operating conditions in addition to its faster start-up and transition operation without divergence from the MPP during sudden varying weather conditions
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Scimone, Tommaso. "Energy Storage in Electric Power Generation Plant from Renewable Sources." Thesis, Università degli Studi di Catania, 2011. http://hdl.handle.net/10761/228.
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During last years the utilization of renewable energy resources has received considerable attention because of the adverse environmental impacts and cost escalation of conventional fuel generation plants. Solar photovoltaic and wind energy industries are two sectors very rapidly growing, and both of them are attracting investments of billions of dollars. However, photovoltaic and wind, like most of the renewable energy sources are characterized by high variability and discontinuity. The high unpredictability of the primary resource makes diffi-cult to forecast the energy production. This is a major trouble for network utility grid management and for the final user, especially in the case of systems operated in island mode. Application of high efficiency energy storage techniques could stimulate in a near future a larger exploitation of renewable energy sources. Energy storage, in fact, could not only improve the quality of the produced power, but, it could also make possible the implementa-tion of sophisticated energy management strategies, fully decoupling the power delivery from power generation.
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Tse, Man-sze. "Benefits and costs of developing renewable energy in Hong Kong /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37120840.
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Ahame, Edmund. "Statistical model for risk diversification in renewable energy." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1008399.
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The growth of the industry and population of South Africa urges to seek new sources of electric power, hence the need to look at alternative power sources. Power output from some renewable energy sources is highly volatile. For instance power output from wind turbines or photovoltaic solar panels fluctuates between zero and the maximum rated power out. To optimize the overall power output a model was designed to determine the best trade-off between production from two or more renewable energy sources putting emphasis on wind and solar. Different measures of risk, such as coefficient of variation (CV) and value at risk (VAR), were used to determine the best hybrid renewable energy system (HRES) configuration. Depending on the investors’ expected returns (demand) and risk averseness, they will be able to use the model to choose the best configuration that suites their needs. In general it was found that investing in a diversified HRES is better than investing in individual power sources.
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Parvanyan, Tigran. "Renewable Portfolio Standard : an analysis of design and implementation issues /." Link to online version, 2005. https://ritdml.rit.edu/dspace/handle/1850/1139.
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Kusakana, Kanzumba. "Optimal operation control of hybrid renewable energy systems." Thesis, Bloemfontein: Central University of Technology, Free State, 2014. http://hdl.handle.net/11462/670.
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Thesis (D. Tech. (Electrical Engineering)) -- Central University of Technology, Free State, 2014For a sustainable and clean electricity production in isolated rural areas, renewable energies appear to be the most suitable and usable supply options. Apart from all being renewable and sustainable, each of the renewable energy sources has its specific characteristics and advantages that make it well suited for specific applications and locations. Solar photovoltaic and wind turbines are well established and are currently the mostly used renewable energy sources for electricity generation in small-scale rural applications. However, for areas in which adequate water resources are available, micro-hydro is the best supply option compared to other renewable resources in terms of cost of energy produced. Apart from being capital-cost-intensive, the other main disadvantages of the renewable energy technologies are their resource-dependent output powers and their strong reliance on weather and climatic conditions. Therefore, they cannot continuously match the fluctuating load energy requirements each and every time. Standalone diesel generators, on the other hand, have low initial capital costs and can generate electricity on demand, but their operation and maintenance costs are very high, especially when they run at partial loads. In order for the renewable sources to respond reliably to the load energy requirements, they can be combined in a hybrid energy system with back-up diesel generator and energy storage systems. The most important feature of such a hybrid system is to generate energy at any time by optimally using all available energy sources. The fact that the renewable resources available at a given site are a function of the season of the year implies that the fraction of the energy provided to the load is not constant. This means that for hybrid systems comprising diesel generator, renewable sources and battery storage in their architecture, the renewable energy fraction and the energy storage capacity are projected to have a significant impact on the diesel generator fuel consumption, depending on the complex interaction between the daily variation of renewable resources and the non-linear load demand. V This was the context on which this research was based, aiming to develop a tool to minimize the daily operation costs of standalone hybrid systems. However, the complexity of this problem is of an extremely high mathematical degree due to the non-linearity of the load demand as well as the non-linearity of the renewable resources profiles. Unlike the algorithms already developed, the objective was to develop a tool that could minimize the diesel generator control variables while maximizing the hydro, wind, solar and battery control variables resulting in saving fuel and operation costs. An innovative and powerful optimization model was then developed capable of efficiently dealing with these types of problems. The hybrid system optimal operation control model has been simulated using fmincon interior-point in MATLAB. Using realistic and actual data for several case studies, the developed model has been successfully used to analyse the complex interaction between the daily non-linear load, the non-linear renewable resources as well as the battery dynamic, and their impact on the hybrid system’s daily operation cost minimization. The model developed, as well as the solver and algorithm used in this work, have low computational requirements for achieving results within a reasonable time, therefore this can be seen as a faster and more accurate optimization tool.
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Templeton, Jeffrey. "Abandoned petroleum wells as sustainable/renewable sources of geothermal energy." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121344.
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Geothermal energy is an important emerging renewable technology that has the potential to provide power from a virtually unlimited reserve worldwide. The downside to exploiting geothermal energy is the capital intensive drilling of the borehole needed to access relatively hot resources located deep under the ground. However, abandoned petroleum wells present an interesting opportunity to circumvent the capital costs associated with drilling. This thesis proposes a sophisticated heat transfer model that is capable of realistically simulating the heat flow through a double pipe heat exchanger and the surrounding rock mass. The sophisticated model is compared with the analytical cylindrical source model, and two numerical models and reaches comparable results. The purpose of this model is to provide an accurate and realistic representation of heat flow and temperature distribution for a heat exchanger retrofitted to an abandoned well. The effects that inlet fluid temperature, insulation, thermal conductivity of the rock mass, mass flow rate of the working fluid, and vertical movement of groundwater have on the sustainability and performance of the double pipe heat exchanger are investigated. A constant power model is also proposed in order to assess the sustainable rate of heat extraction from a geothermal resource.L'énergie géothermique est une technologie renouvelable émergente importante qui a le potentiel de fournir de l'énergie d'une source pratiquement illimitée. Le désavantage de l'énergie géothermique est l'ampleur du capital des forages qui sont requis pour accéder aux ressources plus chaudes. Utiliser les forages de pétrole abandonnés est une opportunité originale pour circonvenir ce désavantage. Cette thèse propose un modèle sophistiqué qui est capable de simuler le flux de chaleur à travers un échangeur de chaleur à tube double et le flux de chaleur à travers la masse rocheuse autour du forage. Le modèle sophistiqué est comparé avec le modèle analytique de source cylindrique, et deux autres modèles numériques et arrivent aux résultats comparables. Le but de cette modèle sophistiqué est de fournir une représentation précise et réaliste du flux de chaleur et la distribution de la température pour un échangeur de chaleur situé dans un forage de pétrole abandonné. Les effets de la température d'entrée de fluide, l'isolation, la conductivité thermique de la masse rocheuse, le taux de débit massique du fluide actif, et le mouvement vertical de l'eau souterraine sur la durabilité et performance de la conception sont enquêtés. Un modèle de puissance constante est aussi proposé pour l'extraction de l'énergie géothermique encore plus durable.
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Kaloud, Tobias. "Renewable Energy Sources and Investment in European Power Transmission Networks." WU Vienna University of Economics and Business, 2017. http://epub.wu.ac.at/5576/1/wp249.pdf.
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During the past decade, renewable energy sources have become an indispensable pillar in European electricity generation. This paper aims at examining if the increasing importance of renewables stimulates investment in European power transmission networks. The question of interest is addressed by an error correction investment model that builds on Neoclassical theory and is further augmented by recent literary findings. Under the proposed threefold estimation strategy, the share of renewables is not found to significantly influence investment spending when the full set of transmission system operators are considered. However, a slight and justified sample restriction leads to the conclusion that a rising share of renewable energy sources substantially increases investment in power transmission networks.Series: Department of Economics Working Paper Series
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Khazaei, Javad Khazaei. "Distributed Coordination and Control of Renewable Energy Sources in Microgrids." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6274.
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Microgrid is an emerging technology in the eld of electrical engineering which employs the concept of Distributed Energy Resources (DERs) in order to generate electricity in a small sized power system. The main objectives of this dissertation are to: 1- design a new control for lower level control of DERs in microgrids, 2- implement distributed upper level control for DERs in microgrids and 3- apply analytical approaches in order to analyze DERs in microgrids. The control in each DER can be divided into two main categories: lower and upper level. Lower level control is the main objective of control in each DER. For example, the lower level control in Photovoltaic (PV) is in charge of transferring the maximum power from sun into the main grid. Unlike the lower level control, the upper level control is an additional control loop on top of the lower level controls. For example, Voltage/Frequency (VF) controllers are installed on top of Active/Reactive (PQ) power controller in energy storage devices as upper level control. In this dissertation, for the lower level control improvements, two widely used DERs are selected (PV, and oshore wind farm) and new control algorithms are developed in order to improve the performance of lower level controllers in these DERs. For the PV lower level improvement, a new control methodology is proposed in order to minimize the maximum power tracking error in PV lower level controller. Second contribution in lower level control is for the oshore wind farm applications based on Multi-Terminal High Voltage Direct Current (MTDC) transmission; a new control is designed in order to minimize the losses in transmission lines through lower level control of High Voltage Direct Current (HVDC) converters.
For the upper level control, this dissertation considers the energy storage as another mostly used type of DER in microgrids. The lower level control for energy storage is in charge of controlling the PQ of the energy storage. The main contribution in the upper level control is to implement the distributed control algorithm based on consensus theory for battery energy storages in order to maximize the efficiency, energy management as well as synchronizing the performance of parallel energy storage devices in microgrids. In this case, the consensus based distributed control algorithm with limited information exchange between neighboring energy storage units is proposed and implemented to validate the claim.
The third contribution of this research is to apply advanced analysis techniques to evaluate the performance of the DERs in microgrids. Two approaches are introduced for microgrid modeling in this research. Firstly, an impedance modeling technique is used to model the oshore wind farm connected to the main AC grid through HVDC transmission line. Multiple Input Multiple Output (MIMO) Nyquist analysis and singular value analysis are used to assess the interactions between HVDC converter and grid. Secondly, an unbalanced microgrid is considered and Dynamic Phasor (DP) analysis is applied in order to nd the stability limitations under different scenarios.
This dissertation has led to seven journal papers (five published, one journal in revision process and one journal submitted recently) and four conference papers.
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Milto, Yuliya <1985>. "Legal Framework of Renewable Energy Sources in the European Union." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amsdottorato.unibo.it/7937/1/Milto_Yuliya_tesi.pdf.
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The thesis analyses the following issues:
historical development of energy and renewable energy sources legislation in the European Economic Community (EEC): the role of energy crisis of 1973 – 1974 in development of renewable energy legislation; international cooperation in the field of energy and renewable energy between EEC and third countries and membership of the EEC in international energy organizations dealing with energy;
the European Union renewable energy policy and legal framework: technological aspects of renewable energy legal framework, transition from renewable energy technological to innovative legal framework, renewable energy policy strategy and legal regulation;
the European Union smart grid legal framework: legal genesis of smart grids and current legal regulation of smart grids, obstacles in smart grid development and legal regulation;
future development of renewable energy sources in the European Union: 2030 renewable energy legal framework, and evaluation of the Renewable Energy Directive 2009/28/EC and its relevance with the new renewable energy objectives of the European Union.
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Reed, Daniel L. "Environmental and renewable energy innovation potential among the states : state rankings /." View online version, 2009. http://ecommons.txstate.edu/arp/291.
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Aljaism, Wadah. "Control method for renewable energy generators /." View thesis, 2002. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20031223.093139/index.html.
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Wang, Huizhi, and 王慧至. "Electrochemical conversion of aluminum energy: energy efficiency, co-production concept and systemcharacteristics." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B4697040X.
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Chiarelli, Andrea. "Energy harvesting pavements using air convection." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/37958/.
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Pavements are one of the most important components of modern civil infrastructure systems. Being constantly exposed to weather conditions, pavements may be subject to heating and cooling cycles, which vary as a function of the location and are proven to reduce the lifespan and reliability of our transport infrastructure. The most extreme effects of weather are generally seen in the form of overheating of the paving materials or freezing of the pavement surface. In this Thesis, natural convection of air is considered as a means to harvest heat from pavements during hot periods and to provide heat to them when the weather is cold. In the research presented, a buoyancy-driven air flow is allowed through metal pipes installed under an asphalt wearing course. The analysis of the phenomena at work is performed from an experimental, computational, and theoretical point of view. The main contribution to research provided by this Thesis it that the experiments performed show that a convection-powered air flow can be effectively used for the reduction or increase of pavement temperatures up to about �5°C. Moreover, the effects of variations in the design of energy harvesting pavements are quantified and discussed, proving that the installation of all pipes in a single row under the wearing course of a pavement is the overall best solution for the implementation of this technology. Finally, CFD simulations suggest that the air pores that are naturally present in asphalt mixtures are not suitable to allow the air flow required for convection-powered energy harvesting, due to both fluid-dynamic and practical reasons.
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Fisher, Jeffrey Dean 1966. "The Icelandic Example: Planning for Hydrogen Fueled Transportation in Oregon." Thesis, University of Oregon, 2009. http://hdl.handle.net/1794/9899.
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xii, 91 p. :ill. (some col.), maps. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.The ability to provide an adequate supply ofrenewable energy necessary to offset the emissions of"zero emission" vehicles is of importance for Oregon's planners and policy makers. An increase in electricity generation caused by the electricity required for zero-emissions hydrogen fuel cell vehicles will result in an increase in greenhouse gas emissions ifrenewable energy is not installed to meet hydrogen fuel cell needs. What are the renewable energy implications for Oregon planners to consider for meeting future fuel cell zero emission vehicle (ZEV) needs? Work done in Iceland can serve as an example for Oregon's need for renewable energy to meet ZEV needs. Icelandic data about hydrogen generation and the renewable energy requirements necessary for ZEVs at the Gtj6thaIs hydrogen fueling station set a benchmark for Oregon planners to consider when figuring the impact of ZEVs.
Committee in Charge: Dr. Robert F. Young, Chair; Dr. Greg Bothun; Mr. Roger Ebbage
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Ramadan, Omar. "Compressed air energy storage for large-scale renewable energy systems for a case study of Egyptian grid." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33601/.
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All across the world, attention is turning to renewable energies to serve at least as a partial substitute to fossil fuels in the global energy mix, braking the latter’s depletion and providing a greener solution for a more sustainable future. However, the intermittent nature of most renewable energy sources, wind and solar in particular, raises major concerns over the integration of these technologies, on a large scale, to grid systems. This thesis focuses on large-scale renewable energy storage systems, primarily compressed air energy storage (CAES) systems, which are particularly well suited for renewable energy applications. CAES can play a major role in shaping the future of renewable energy systems for not only can it bring load levelling to the system, but it can also add substantial value by providing ancillary services to the grid. The main focus of this research is adiabatic CAES which endeavours to minimize the use of natural gas by using recuperators and thermal energy storage systems, where the heat from the air during the compression stages is absorbed by a heat transfer fluid, stored, and then supplied back during the expansion process. This project aimed to explore the potential of CAES systems as an energy storage technology for large-scale grid integrated renewable energy system. A computer model was developed to size the different components in the CAES system and also to predict the operational performance of the CAES system for different conditions using MATLAB programming. The thermal energy storage of an adiabatic CAES system was optimized using CFD analysis and experimental testing of the thermal energy storage system was carried out to validate the models. Also, an economic study was performed to assess the feasibility of the CAES system based on a case study of the Egyptian grid. The dynamic simulation of a novel configuration of an adiabatic CAES system showed that the system can achieve improved performance compared to existing CAES plants, while the economic study showed that CAES can improve the economics of a wind farm, at least by the standards of our chosen case study location.
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Schmitz, Anthony. "Effect of oil prices on returns to alternative energy investments." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31843.
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Thesis (M. S.)--Economics, Georgia Institute of Technology, 2010.Committee Chair: Vivek Ghosal; Committee Member: Byung-Cheol Kim; Committee Member: Chun-Yu Ho; Committee Member: Tibor Besedes. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Murray, Angus. "Modelling and heuristic optimization of a hydrogen producing renewable energy system." Thesis, University of Aberdeen, 2013. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=202138.
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The reliable supply of hydrogen to a vehicle re-fuelling station has been tackled in this thesis. A currently operational system based on supplying energy from a bio-generator, fuelled from biogas generated by organic matter in an Anaerobic Digester, formed the basis of an expanded renewable energy system. The criterion for the new design was the supply of energy to an electrolyser/compressor/storage system at minimum cost and minimum interruption to supply. By separating hydrogen production from energy generation, the operating parameters of the electrolyser and compressor were optimized, leading to an energy load profile that guaranteed a reliable supply of hydrogen sufficient to fuel the daily needs of up to two hydrogen fuelled vehicles. Based on the energy load profile, a renewable energy system was designed around the existing bio-generator. A multi-objective optimization by Genetic Algorithm was employed to design a hybrid renewable energy system that minimized lifetime costs and unmet load. The resulting design consisted of a mixture of wind turbines, batteries, inverters/rectifiers, as well as the bio-generator. A control strategy that directed the interaction of all components was also produced. Multi-objective optimization by Genetic Algorithm was found to be a reliable, efficient method in designing a complex hybrid renewable energy system with non-linear characteristics. The results of modelling and simulation showed that an uninterrupted supply of energy could be produced, based on specific meteorological conditions, at a minimal cost. The research has shown that it is possible to develop a design that produces hydrogen reliably purely from renewable energy sources. The design is flexible enough to integrate other renewable energy sources and technologies as they develop.
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Akoush, Sherif. "Exploiting surplus renewable energy in datacentre computing." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610058.
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Robbins, Curt. "Small scale renewable energy storage system using hydrogen combustion." abstract and full text PDF (UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1456487.
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Macbeth, John Noel. "A thermal charge system for variable electrical supplies from renewable sources." Thesis, University of Aberdeen, 2013. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=202380.
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In a time of a fast growing renewable electricity generation sector, there are challenges regarding the integration of such generation with current transmission infrastructure. Such challenges include problems associated with the intermittent power output of renewable energy sources and the inability to control there output to meet varying electrical demand. Using part of this available energy for the provision of domestic heating loads may help bridge the gap between supply and demand. The use of intermittent electrical energy sources for charging water based thermal energy stores was identified as a research gap. This research project studies the use of intermittent electrical supplies from wind turbines for the provision of space heating and hot water in domestic buildings. It also addresses how solar water heating may be incorporated into the same thermal energy storage unit to create a hybrid system. This thesis outlines and analyses two charge strategies that may be used to promote stratification in water based thermal energy stores when adding intermittent electrical energy. The first makes use of multiple heating elements switched on in sequence (direct system) while the second uses buoyancy forces to take cool water from the bottom of the tank, pass it through the heating element and then place it back in at the top of the tank at a higher temperature (side-arm). The research method includes; 1) a simplified theoretical simulation of direct and side-arm configurations in the transient system simulation software (TRNSYS) to identify system performance when charged from wind and solar energy; 2) a detailed theoretical representation of the side-arm charge mechanism with a modulating valve for TRNSYS; 3) an empirical validation of the detailed theoretical model of the side-arm charge cycle. Outcomes from the simplified theoretical model indicate that the side-arm configuration may have benefits over the direct configuration due to reduced heat loss from the tank, reduced auxiliary energy consumption and increased solar collector performance. The detailed theoretical representation of the side-arm was calibrated using the empirical data gathered. From this, important parameters affecting the performance of the side-arm charge cycle are evaluated. These include the effects of tank height, operating temperature and the power range from the intermittent electrical supply. It is identified that the assumptions made in the simple model are not possible to reproduce in real life and that an analysis using the complex model must be made in order to evaluate any potential benefits of the side-arm over a direct configuration.
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Au, P. N., and 區沛能. "Pearl River Delta and the development of renewable energy in HongKong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31255723.
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Yee, Victoria E. "Predicting the renewable energy portfolio for the southern half of the United States through 2050 by matching energy sources to regional needs." Scholarly Commons, 2012. https://scholarlycommons.pacific.edu/uop_etds/808.
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Worldwide energy consumption is estimated to double between 2008 and 2035. Over-dependence on energy imports from a few, often politically unstable countries, and unpredictable oil and gas prices, pushes energy to a critical agenda. While there is an agreement that we need to change the production and consumption of energy, there is still disagreement about the specific changes that are needed and how they can be achieved.
The conventional energy plans relying primarily on fossil fuels and nuclear technologies, which are in need of transformation due to limited resources and carbon dioxide emissions. Energy efficiency improvements and renewable energy should play a leading role in the America's energy future. Energy and environmental organizations believe that renewable energy and energy efficiency can meet half of the world's energy needs by 2050.
This thesis describes a model that predicts renewable energy portfolios for the Southern portion of the United States, by evaluating multiple renewable energy sources such as solar, wind, hydropower, biomass, and geothermal. The Southern US is divided into three regions: Southwest, South Central, and Southeast, which are chosen given their location and the level of abundance of renewable resources, thereby minimizing inefficiencies and losses associated to the present generation system. A mathematical predictor takes into account variables such as supply/demand, non-renewable/renewable sources, and time.
From the results, the Southwest and South Central regions confirm an surplus of renewable electricity by 2050, but the Southeast region does not have enough renewable resources to detach itself from the use of fossil fuels. The South Central region begins producing a surplus of renewable energy in 2014 and reaches an excess amount of 14,552 billion KWh by 2050. This means there will be no need to transfer electricity over long distances, which will increase the overall efficiency of electrical generation.
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Ocampo-Corrales, Diego B. "On Renewable Energy Innovation and its Knowledge Flows’ Sources and Nature." Doctoral thesis, Universitat de Barcelona, 2020. http://hdl.handle.net/10803/670011.
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El núcleo de la tesis consta de tres capítulos en los que se explora la naturaleza de los flujos de conocimiento que influyen en la innovación en energías renovables. En los tres capítulos se utiliza información de patentes europeas a nivel regional para poder capturar el concepto de innovación. En el segundo capítulo explora la naturaleza de la base del conocimiento subyacente en las energías renovables. Se plantea que esta tecnología tiene un mayor contenido de conocimiento científico y abstracto que el resto de campos tecnológicos en general. Esta característica haría que, por un lado, el flujo de conocimiento desde la academia y ciencia sea más importante para la innovación en energías renovables que para el resto de innovación en general, y que por otro lado, el flujo de conocimiento no estaría tan restringido geográficamente, hecho que es un hallazgo común en la literatura. Empleando información de las citas hechas por las patentes para medir los flujos de conocimiento, se estima una función de producción de conocimiento. Se distingue entre el flujo del conocimiento desde el sector científico del proveniente del sector técnico. Los resultados muestran que el conocimiento proveniente de la ciencia es más importante para para la innovación en energías renovables que para el resto de innovación en general. También se halla evidencia de que los flujos de conocimiento provenientes del sector técnico que influyen en la innovación en energías renovables estarían menos constreñidos geográficamente que los que influyen en el resto de innovación en general. Este hallazgo se debería al mayor contenido de conocimiento abstracto y científico, que es más fácil de codificar y por lo tanto más fácil de transportar en el espacio.
El tercer capítulo estudia cómo diferentes fuentes de conocimiento pueden influir en que un inventor con experiencia previa en otros campos, patente en energías renovables. Se postula que un inventor puede adquirir conocimiento o ideas de tres fuentes: su red de coautores, la compañía en la que trabaja y de su ámbito local. Además, se plantea que en estas tres fuentes, un inventor podría ser influenciado por sus pares de forma directa, ya sea por un efecto ‘manada’ o porque ellos proporcionan conocimiento especializado sobre energías renovables que es necesario para producir tecnología en este campo. Se postula que las fuentes más cercanas de conocimiento, son las que influirían más en que un inventor se aventure en un campo en el que no tiene experiencia previa, pues las relaciones más cercanas facilitarían que fluya conocimiento más complejo. Por tal motivo, el conocimiento más importante provendría de la red de coautores. El análisis empírico se realza utilizando información de patentes, de la cual se identifica a los inventores, su centro de trabajo y la región donde radican, asi como su experiencia previa en innovación. Los resultados muestran que el factor más importante para que un inventor se aventure en innovar en energías renovables es tener en su red de coautores a algún inventor que haya patentado antes en energías renovables. Esto implicaría que para entrar en el campo de la innovación en energías renovables es importante contar con alguien con experiencia previa en dicho campo, pues podría ejercer influencia personal y también contribuir con conocimiento específico en este campo tecnológico.
Por último, el cuarto capítulo de la tesis ahonda en la relación de los diferentes tipos de distancia que podrían existir: distancia cognitiva, las formas distintas de entender un mismo fenómeno, distancia social, la interacción directa entre individuos basada en la confianza, distancia organizacional, las distintas reglas y normas que enmarcan las relaciones de los individuos entre distintas organizaciones, y distancia geográfica, la distancia física entre individuos. Se plantea que debe haber un equilibrio entre el conocimiento próximo y el conocimiento distante en términos cognitivos, pues el conocimiento próximo facilitaría el flujo de información, pero quizás redundante, mientras el distante aportaría ideas nuevas, pero quizás difíciles de comprender para los interlocutores. Se busca explicar si es el conocimiento próximo o distante el que influye en que un inventor experimentado patente por primera vez en energías renovables y de donde provendría este conocimiento (la red de coautores, la firma o el ámbito regional/local). Utilizando la clasificación tecnológica de las patentes se establece lo que sería conocimiento próximo o distante por medio de la coocurrencia de clases tecnológicas en las patentes. Asi, se construye que tan próximo y distante el conocimiento de un inventor con el de su red de coautores, de la compañía donde trabaja y del conocimiento de su entorno. También se mide que tan próximo está el conocimiento de un inventor respecto al conocimiento en energías renovables. El principal hallazgo es que el factor más importante para que un inventor patente en energías renovables sería que su propio conocimiento previo esté próximo al de energías renovables. Luego, el conocimiento de los coautores sería importante en tanto sea conocimiento distante. De esta forma se alcanzaría ese equilibrio entre conocimiento próximo (el del inventor) y conocimiento distante (el de los coautores) para innovar en un campo nuevo. La razón de esto sería que el conocimiento distante, podría ser transmitido por los coautores, pues ellos son quienes más relación tienen con un inventor, por tanto podrían transmitir conocimiento más complejo de entender.
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Turesson, Jonas. "Potential for Renewable Energy Sources (RES) in Grenoble, Delft & Växjö." Thesis, KTH, Industriell ekonomi och organisation (Inst.), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-34442.
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Sustainable cities is an area that has grown in size over the last couple of years. The SESAC (Sustainable Energy Systems in Advanced Cities) is a EU-project looking at the potential to increase the share of Renewable Energy Sources (RES) and promote energy efficiency measures in different EU cities. This master thesis is a part of that project. Specifically, the thesis examines the cities of Grenoble, Delft and Växjö and looks at what measures regarding RES and energy efficiency have been taken historically, both under the SESAC project and otherwise, and assesses the possibility of further measures in the cities. The main RES evaluated are wind power (large scale and urban), solar (PV and thermal) and waste treatment (waste incineration and biogas production). The feasibility of these renewable technologies is evaluated both physically, technically and economically for each city. Further, the historical and current hinders and promoters in the form of different support schemes and other economic and institutional schemes are summarized for each country and city and the effects of which included in the feasibility calculations. Also, current CO2 emissions of Grenoble, Delft and Växjö are stated and the impact of implementing the measures examined is calculated. A comparison between the three cities is also made and suggestions are made to what they can learn from each other and what synergies there are. Results show that the technical potential for RES is sizeable in the cities, as seen in Table 1. Important to note are the differences between the cities. Besides from their differences in population size, ranging from 83 000 (Växjö) and 96 000 (Delft) to 400 000 (Grenoble), available land area as well as climate are very different in the cities, therefore affecting the potential for the RES technologies. RES potential [GWh] Grenoble Delft Växjö Wind 458 1,2 (Urban only) 297-2000 Solar PV 375 150 0,06-0,3 Waste treatment 41 11 10 Table 1. Technical potential of RES in Grenoble, Delft and Växjö Looking at the economic potential, however, the picture is not as optimistic. The only economically feasible investments of the options in Table 1 are investing in solar PV in Grenoble and Delft (IRR of 0-10%) and wind in Växjö (IRR of 4%). All other investments have negative NPV:s and IRR:s, meaning that either the cost of the technologies must be reduced or more favorable support scheme be introduced in order to make the them profitable.
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Li, Yunbo. "Resource allocation in a Cloud partially powered by renewable energy sources." Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2017. http://www.theses.fr/2017IMTA0019/document.
Full textAbstract:
La plupart des infrastructures de cloud efficace en énergie proposées dans la littérature ne tiennent pas compte de la disponibilité électrique et des énergies renouvelables dans leurs modèles. L’intégration des énergies renouvelables dans les centres de données réduit considérablement leur consommation d’énergie et leur empreinte carbone. Étant donné que l’énergie renouvelable est intermittente et fluctue en fonction du temps, elle est habituellement sous-utilisée. Nous abordons le problème de l’amélioration de l’utilisation des énergies renouvelables dans un centre de données unique et étudions deux approches : la planification opportuniste et le stockage de l’énergie. Nos résultats démontrent que les deux approches permettent de réduire la consommation d’énergie non-renouvelable sous différentes configurations. Nous étendons ce travail au contexte des Edge Clouds et de l’Internet des Objets dans le cas de l’analyse de flux de données. Nous montrons comment rendre les Edge Clouds plus verts avec une production d’énergie renouvelable sur site combinée à un stockage d’énergie et à une dégradation de performance des applications des utilisateursMost of the energy-efficient Cloud frameworks proposed in literature do not consider electricity availability and renewable energy in their models. Integrating renewable energy into data centers significantly reduces the traditional energy consumption and carbon footprint of these energy-hungry infrastructures. As renewable energy is intermittent and fluctuates with time-varying, it is usually under-utilized. We address the problem of improving the utilization of renewable energy for a single data center and investigate two approaches: opportunistic scheduling and energy storage. Our results demonstrate that both approaches are able to reduce the brown energy consumption under different configurations. We extend this work to the context of Edge Clouds and Internet of Things on the use case of data stream analysis. We show how to make Edge Clouds greener with on-site renewable energy production combined with energy storage and performance degradation of the users’ applications