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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Větrná elektrárna grid-off, princip, účinnost, návratnost / The grid-off Wind Power, Principle, Effectiveness, Return

Havránek, Miroslav January 2013 (has links)
This Master´s thesis deals with problematics of wind powered generators and their use in off-grid systems. In its first chapters aspects of wind as a power source are analyzed. Further on the thesis focuses on individual components of the off-grid systems. Also designing procedures of these systems are presented in the paper. The key parts of the thesis are 3 off-grid wind power system designs, which can be used to power a family house, and their energetical and economical evaluation.
152

Studie blackoutu s ohledem na jadernou elektrárnu Dukovany / Electricity blackout study with regard to the nuclear power plant Dukovany

Žák, Jiří January 2013 (has links)
The entire diploma thesis analyses causes, consequences and repercussions of an electricity grid network blackout and its impact to the respective consumers. Remarkable blackouts recorded since 1965 are briefly described and basic available information is considered. The grid standard fixing measures and electricity delivery priorities are characterized. The thesis also pays attention to entire Czech Republic grid availability and its blackout endurance as well as to its robustness within last several years. Indirect Fukushima event influence to the Czech Republic electricity system is mentioned. The main part of the thesis comprises of four big European grid blackouts causes and consequences, their comparison to each other and to the Dukovany nuclear power plant grid blackout drill scenario. The preventive and standard corrective measures against blackouts are pointed out.
153

Návrh projektu a aplikace metodiky projektového managementu ve společnosti ZTC Holding, SE / The Proposal of the Project and Application of Methodology for Project Management in the Company ZTC Holding, SE

Kubát, Richard January 2011 (has links)
Tato diplomová práce analyzuje současnou situaci ve firmě v oblasti projektového řízení při výstavbě solární elektrárny. A pokusí se na základě norem a metodik projektového řízení navrhnout konkrétní kroky, které povedou ve firmě ke zlepšení řízení projektů. Práce je rozdělena do dvou hlavních částí - teoretické a praktické. První část popisuje společnost ZTC Holding SE a zabývá se teoretickými základy řízení projektů, je zde definován management a jeho funkce, řízení projektu, popis projektu, popis činnosti projektového manažera a jeho týmu. V této části je také teorie časové analýzy projektu, včetně metody Critical Path Method (CPM) a Ganttova diagramu. Druhá část se zaměřuje na analýzu vnějšího prostředí pomocí analýzy PESTLE, analýzy SWOT a analýzy vnitřního prostředí 7S. Tato část také pojednává o přesném vymezení projektu, jeho cílů, které jsou definovány metodou SMART. Tato část končí definováním konkrétních rizik, která se mohou vyskytnout během životního cyklu projektu. Závěr diplomové práce je zaměřen na celkové hodnocení navrhovaných postupů, které by měly zlepšit výkonnost ZTC Holding, SE.
154

Parogenerátor pro jadernou elektrárnu s rychlým reaktorem / Steam generator for nuclear power plant with fast reactor

Karička, Radoslav Unknown Date (has links)
The aim of the project is to design a steam generator in which the sodium flows pipeline hand, and on the other hand, water flow and water vapor (H2O). The main idea of this thesis is to propose such a steam generator, to avoid or eliminate the possibility of adverse reactions of sodium with water and, if this phenomenon occurs, thus minimizing the damage caused by this reaction. The work contains information on the implementation of steam, steam option, the necessary calculations for the design and construction and evaluation.
155

Analýza nesrovnalostí malé vodní elektrárny Beneš. / Contradictions analysis of small water power Beneš.

Kuchař, Jan January 2009 (has links)
This master‘s thesis deals with small water power plant Beneš. The first part of the thesis tries to find causes of low efficiency of this power plant. The second part contains suggestions of construction changes for increasing of efficiency – design of new runner blades and basic parameters of new distributor.
156

Větrná elektrárna ve vybrané lokalitě / Wind power plant in a chosen locality

Dohnal, Petr January 2011 (has links)
This master thesis deals with problematic wind power plants. There are described advantages and disadvantages of wind power plants and their environmental impacts. Thesis include chosen locality for wind power plant, chosen fitting types of turbines and calculation which choosing turbine for chosen locality. There are accomplished parametric studies of main parameters. From this study is chosen best fitting model of wind turbine. In the end are adduced statistics from Czech Republic, Europe and world.
157

Návrh Kalinova cyklu a určení hlavních rozměrů jeho tepelné turbiny pro geotermální elektrárnu. / Design Kalina cycle for geothermal power plant and its turbine.

Luermann, Július January 2012 (has links)
This master’s thesis analyses Kalina cycle, a power cycle where ammonia – water solution is used as a working fluid. The first part of this study introduces us to the Kalina cycle, presents its advantages and disadvantages, characteristics of the working fluid and its applications. Second section concerns with the method of cycle design and describes the calculation model made in this thesis. The calculation model is attached in a separate .XLSM file. The third part shows calculation of the cycle for given parameters, determination of cycle efficiency and main proportions of the thermal turbine. In the conclusion are the interpretations of the calculations results.
158

Modely a analýzy v kontejnmentovém systému s potlačením tlaku při haváriích s únikem chladiva / Models and analysis of the pressure suppression system containment, during the loss of coolant accidents

Studýnka, Radim January 2014 (has links)
This diploma thesis deals with a pressure suppression system containment during the loss of coolant accidents. It is focused on the containment systems of the nuclear power plants with VVER-440/V-213 reactors. There is described the process of loss of coolant accident. There was designed input model which consists of the zones representing the areas which are connected with junctions and heat structures. Were then selected input parameters for the model calculations. And finally, there have been several calculations for the selected parameters.
159

Kapalné výpusti 14C v českých jaderných elektrárnách a odhad jejich radiologických dopadů / Liquid discharges of 14C in the Czech nuclear power plants and estimation of their radiological impacts

Chvátalová, Barbora January 2017 (has links)
This thesis deals with the determination of 14C activity in liquid discharges from the Czech nuclear power plants and with the estimation of their radiological impacts on the vicinity of nuclear power plants. This work summarizes the issue of 14C liquid discharges of several nuclear power plants in the world and Czech nuclear power plants are compared to them. The sewage routs of liquid discharges from control tanks to waste water station are described in this thesis for both power plants - Dukovany and Temelín. Measured values of the 14C activity in liquid discharges from nuclear power plants Temelín and Dukovany are presented in this work. The procedure for calculating the exposure of representative persons as a result of liquid discharge of 14C activity is described in this thesis. The resulting values of annual commited effective dose for each age category of representative persons are presented in this work.
160

Feasibility study on the implementation of a boiling condenser in a South African fossil fuel power plant

Grove, Elmi January 2016 (has links)
The South African electricity mix is highly dependent on subcritical coal-fired power stations. The average thermal efficiency of these power plants is low. Traditional methods to increase the thermal efficiency of the cycle have been widely studied and implemented. However, utilising the waste heat at the condenser, which accounts for the biggest heat loss in the cycle, presents a large potential to increase the thermal efficiency of the cycle. Several methods can be implemented for the recovery and utilisation of low-grade waste heat. This theoretical study focuses on replacing the traditional condenser in a fossil fuel power station with a boiling condenser (BC), which operates in a similar manner to the core of a boiling water reactor at a nuclear power plant (Sharifpur, 2007). The system was theoretically tested at the Komati Power Station, South Africa's oldest power station. The power station presented an average low-grade waste heat source. The BC cycle was theoretically tested with several working fluids and numerous different configurations. Several of the theoretical configurations indicated increased thermal efficiency of the cycle. The BC cycle configurations were also tested in two theoretical scenarios. Thirty configurations and 103 working fluids were tested in these configurations. The configuration that indicated the highest increase in thermal efficiency was the BC cycle with regeneration (three regenerative heat exchangers) from the BC turbine. A 2.4% increase in thermal efficiency was obtained for the mentioned theoretical implementation of this configuration. The working fluid tested in this configuration was ethanol. This configuration also indicated a 7.6 MW generating capacity. The increased thermal efficiency of the power station presents benefits not only in increasing the available capacity on South Africa's strained grid, but also environmental benefits. The mentioned reduction of 7.6 MW in heat released into the atmosphere also indicated a direct environmental benefit. The increase in thermal efficiency could also reduce CO2 emissions released annually in tons per MW by 5.74%. The high-level economic analysis conducted, based on the theoretically implemented BC cycle with the highest increase in thermal efficiency, resulted in a possible saving of R46 million per annum. This translated to a saving of R19.2 million per annum for each percentage increase in thermal efficiency brought about by the BC cycle. The theoretical implementation of the BC, with regeneration (three regenerative heat exchangers) from the BC turbine and ethanol as a working fluid, not only indicated an increase in thermal efficiency, but also significant economic and environmental benefits. / Dissertation (MEng)--University of Pretoria, 2016. / Mechanical and Aeronautical Engineering / MEng / Unrestricted

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