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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.
321

Análise da inserção de sistemas fotovoltaicos conectados à rede elétrica da Ilha de São Vicente (Cabo Verde) / Analysis of the insertion grid connected photovoltaic systems in the island of São Vicente (Cape Verde)

Lima, Ciliana Karine Dias 11 December 2017 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2017-12-18T16:25:14Z No. of bitstreams: 2 Dissertação - Ciliana Karine Dias Lima - 2017.pdf: 23149224 bytes, checksum: c070892c298f576da2daf6724723a45b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-12-19T12:03:47Z (GMT) No. of bitstreams: 2 Dissertação - Ciliana Karine Dias Lima - 2017.pdf: 23149224 bytes, checksum: c070892c298f576da2daf6724723a45b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-12-19T12:03:47Z (GMT). No. of bitstreams: 2 Dissertação - Ciliana Karine Dias Lima - 2017.pdf: 23149224 bytes, checksum: c070892c298f576da2daf6724723a45b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-12-11 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Sustainable development is a present issue in world society and it is also a strategic challenge for Cape Verde’s energy policy in coming years because the large fragilities in the electrical system in Cape Verde such as, dependence on imports of fuels, geographical dispersion, the high costs associated with managing energy systems and the great energy waste. The bet on photovoltaic systems may be one of the alternatives to reducing these fragilities. In this context, the present work highlights the great existent potential for use of renewable energy focused on solar energy. The text describes incentives for the production of electric energy based on renewable sources and presents analyses on the implementation of two grid-connected photovoltaic systems in the island of São Vicente. One of the systems is a photovoltaic rooftop 19.8 kWp plant installed in a public secondary school building and the other system is 3 MWp photovoltaic power plant connected to electrical utility grid in São Vicente Island. The study included design, operation simulation of São Vicente Island distribution network in the presence and absence of photovoltaic systems and financial analyses in order to determine payback time, actual present value, intern return rate of investment and financial sensibility analyses to assess the influence of Wp cost and interest rate on the financial figures. The results show that the implementation of photovoltaic systems is attractive in financial and technical terms, the microgeneration system causes a large reduction in energy acquired by the network, and the large power plant has not worsened the appropriate operating voltage levels and decreased the system's active losses. / O desenvolvimento sustentável é uma questão presente na sociedade mundial e é também um desafio para a política energética de Cabo Verde nos próximos anos, devido às grandes fragilidades do sistema elétrico do arquipélago, tais como a forte dependência da importação dos combustíveis fosseis, a dispersão geográfica, os elevados custos associados à gestão dos sistemas energéticos e o grande desperdício energético. A aposta em sistemas fotovoltaicos é uma das alternativas para a redução dessas fragilidades. Neste contexto, o presente trabalho destaca o grande potencial existente em Cabo Verde para utilização de energia renovável com o foco na fonte solar. O trabalho descreve os incentivos legais locais para a produção de energia elétrica com base em fontes de origem renovável e apresenta a análise da implantação de dois sistemas fotovoltaicos conectados à rede elétrica na ilha de São Vicente. Um deles é um sistema de microgeração fotovoltaica de 19,8 kWp instalado em um edifício público de ensino e o outro é uma usina fotovoltaica de grande porte de 3 MWp, ligada à rede elétrica e também localizada na ilha de São Vicente. O estudo inclui o dimensionamento, a simulação de operação da rede de distribuição da ilha de São Vicente na ausência e na presença de sistemas fotovoltaicos. São feitas análises financeiras a fim de determinar o tempo de retorno dos investimentos, o valor atual líquido e a taxa interna de retorno dos investimentos. Também é feito uma análise de sensibilidade financeira para avaliar a influência do custo do Wp instalado e da taxa de juros do financiamento sobre os parâmetros financeiros. Os resultados mostram que a implementação dos sistemas fotovoltaicos é atrativa em termos financeiros e técnicos. A instalação do sistema de microgeração provoca uma grande redução da energia adquirida junto à rede pela unidade consumidora. É mostrado também que a usina de grande porte notadamente não alterou os níveis de tensão de funcionamento da rede e proporcionou uma diminuição das perdas ativas do sistema.
322

Návrh a realizace mobilní fotovoltaické elektrárny / Design and Realization of Mobile Photovoltaic Power Station

Lednický, Ján January 2017 (has links)
This diploma thesis entitled Design and realization of a mobile photovoltaic power plant is dividet into two parts. In the first, theoretical part one can learn about the state of representation of renewable energy sources in the field of electrical power engineering and about the structure of photovoltaic power station systems. The secont part of this thesis is focused on the own design and realization of the mobile photovoltaic power plant, on the selection of individual suitable components and ther dimensioning. In addition, a model of a mobile power plant has been created, on the basis of which the power plant was constructed. Finally, one can find a source code analysis of a power plant monitoring using a microcontroler
323

Ostrovní systémy / Autonomous energy systems

Dolinský, Filip January 2018 (has links)
Master thesis deals with usage issues of autonomous, self-sufficient and decentralized systems. In the first part convectional and experimental sources for autonomous systems are disclosed. Second chapter deals with accumulation of electrical and thermal energy and possibilities of applications. 3rd part is focused on pilot project realized for autonomous and smart systems, which were built in last years. In the 4th chapter electrical and thermal energy consumption curves are made on daily and monthly basis for 4 type objects. In the fifth part issue of autonomy is explained, and for type buildings solutions are made with additional return on investment. The last chapter is focused on calculation of thermal accumulator and briefly discloses small district heating.
324

Tepelné čerpadlo napájené z fotovoltaického systému / Heat Pump Supplied from Photovoltaic System

Kaděra, Jan January 2020 (has links)
This thesis provides heat pump usage in heating mode, heating of potable water or cooling mode. The heat pump is connected with photovoltaic power plant. The main aim of this study is to create photovoltaic system connected with heat pump and present the results of an energetic and economic evaluation. The theoretical part describes principle function heat pumps, photovoltaic power plants and components. The study provides as well a description of heating systems with a heat pump used for space heating or cooling. In the practical part of this thesis was performed calculation of energy consumption in a building. Based on this data, has been selected a suitable heat pump. To reduce the energy consumption was designed a hybrid photovoltaic power plant with a battery accumulation. Utilization of electric energy from photovoltaic system was calculated. Solutions provide the option of the energy flow analysis in specific interval. Results are summarized in the energetic and economic evaluation. The proposed solution can be applied for reconstruction or construction of a new building, focused on usage of renewable resources and emissions reduction.
325

Připojování fotovoltaických zdrojů k distribuční síti / Connecting of the Photovoltaic Power Sources to the Distibution Network

Ondroušek, Luděk January 2009 (has links)
This work is focused on the current issues, which are associated with the connection of fotovoltaic sources to the distribution grids. An example of these problems can be the connection of the bigger fotovoltaic power plant to the part of the grid with small short-circuit power. In consequence of this, it can happen that the quality parameters (voltage) of this grid are undesiderably influenced. Integral part of the connection procedure of the new sources to the grid is also a design and method of the power output, which is also part of this work.
326

Návrh optimalizace spotřeby elektrické energie z fotovoltaické elektrárny / Proposal for power consumption optimization of photovoltaic power plant

Mareček, Jan January 2015 (has links)
This master’s thesis is focused on opportunities of optimization of electric power consumption from photovoltaic power plant. In theoretical part are presented basic principles and possibilities of photovoltaic system connection. It continues with an overview of backup systems and types of batteries. Practical part is about prediction of production and consumption of electric power, possibilities of power management and optimization. Next chapter deals with battery life cycle and their suitability for photovoltaic system. The last part of this thesis is the quantification of the stored electric energy economic value.
327

Návrh a zhodnocení výstavby a provozu fotovoltaické elektrárny / The Evaluation of the Construction and Running of a Photovoltaic Power Plant

Vozár, Jan January 2010 (has links)
Tato diplomová práce se zabývá problematikou výstavby a provozování fotovoltaické elektrárny v podmínkách České republiky. Diplomová práce se skládá z části teoretické, analytické a návrhové. V části teoretické kde jsou rozebrána teoretická východiska, která jsou následně aplikována v dalších částech. Analytická část pojednává o podmínkách a překážkách výstavby a provozu fotovoltaických elektráren na území ČR. Část návrhová obsahuje vlastní návrh možných řešení fotovoltaické elektrárny a doporučení nejvhodnějšího řešení.
328

Zlepšení procesů při realizaci zakázky / The Improving Processes in Realizing of Contract

Malinovský, Ondřej January 2010 (has links)
The topic of my final thesis is through analysis of solar market segment and business processes of company ABC, which is operating in this market. On the basis of gained information I am proposing changes in processes by contract implementation in analyzed company. In conclusion the thesis is evaluating economical impact of proposed improvements.
329

Podnikatelský záměr / Business Plan

Hrazdil, David January 2010 (has links)
This master thesis focuses on selecting the best variant of the business plan for renewable energy, particularly solar power. Analyzes the current situation in the Czech Republic, surroundings and home environment for renewables. Several investment proposals with investment efficiency evaluation methods chosen the best option is acceptable for implementation.
330

Ověření provozní výkonnosti a optimalizace FVE / PV plant performance evaluation and optimization

Špinar, Marek January 2016 (has links)
The Master´s thesis deals with issues of operational performance of two photovoltaic power plants. In the thesis is stated the history of photovoltaics, description of photovoltaic effect, used materials and production technology of the most used material in PV industry – Silicon. The basic parts and parameters of photovoltaic power plant are described. Thesis also solves, how could be done the first and periodically control due to relevant directives. The ways of diagnostics potentional failures, methods of measuring and the exam of monitoring system are stated. Practice part is focused on measuring and comparing operational performance of FVE Kurdějov and FVE Šakvice II. Operational performance was calculated from exported data for years 2014 and 2015. The thesis also contains measuring of each string connected to inventors, which are installed on the power plant. The result is an identification of strings with decreased operational performance. Based on that was created recommendations for optimalization and increase of the performance. The last part is software for simulation of photovoltaic power plant. This SW calculates potentional energy, which could be produced in a day with available data export. The calculation is defined by parameters, which are assigned.

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