This diploma thesis is focused on proposition of non-freezing heat transfer fluid for solar systems. Fluid will be based on mixture of new available compound propane-1,3-diol with water and modern corrosion inhibitors. Then will be investigate, if this new compound is competetive to common used liquids like ethylene glycol or propylene glycol.

This thesis is focused on proposition of non-freezing heat transfer fluid. Fluid will be based on mixture of propane-1,2,3-triol with water and modern corrosion inhibitors. Then will be investigate, if this new compound is competetive to common used liquids like ethylene glycol or propylene glycol.

This Master´s thesis deals with the influence of small household appliances to the economy of solar systems. The theoretical part is focused to solar systems and describes the possibilities of linking these systems with small household appliances. It adds an effective, ecological and economic aspect of washing and small home appliances suitable for economic household. The practical part evaluates the economic utilization of solar systems with small household appliances.

Masters’s thesis describes the use of solar energy for solar thermal systems used for domestic hot water heating. It is about the size of the incident solar radiation on Earth. Distributes various types of solar collectors for water heating. It deals with the monitoring, remote management of this system and the design of optimal control used in this area.

Orientador: Elaine Maria Cardoso / Resumo: O presente trabalho consistiu na análise teórica e experimental de um sistema híbrido PVT - fotovoltaico/térmico. Este consiste de um painel fotovoltaico (PV), com sistema de rastreamento, para aproveitar a radiação solar direta e difusa, e de um sistema d e resfriamento por convecção forçada acoplado, permitindo gerar eletricidade e calor em um único processo além de reduzir a temperatura de operação de um painel solar fotovoltaico comercial e, assim, melhorar sua eficiência energética. O módulo PV está instalado na região noroeste do estado de São Paulo. O conjunto experimental possui um sistema de rastreamento solar azimutal de eixo simples; a tensão e a corrente de saída do painel foram medidas para quantificar a potência produzida levando em consideração diferentes condições de operação. Todos os testes foram realizados in loco usando um painel fotovoltaico comercial, sempre levando em consideração as condições meteorológicas do dia. O rastreamento solar aumenta em 45,5% a energia gerada para um dia do mês de junho em relação a um sistema fixo. O painel fotovoltaico com a parte posterior isolada termicamente opera em condições 15 °C a 20 °C mais quente que um painel não isolado, o que implica em perdas energéticas da ordem de 7,6%. O trocador de calor tipo serpentina, com uso de água deionizada, não mostrou desempenho satisfatório ao resfriar o módulo fotovoltaico devido à significativa resistência térmica de contato com a face posterior do módulo. A análise teórica apre... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present work consisted of a theoretical and experimental analysis of a hybrid PVT – photovoltaic/thermal system. This system consisted of a photovoltaic (PV) panel with a solar tracking system to take advantage of direct and diffuse solar radiation and a forced convection cooling system. This allows the generation of electricity and useful heat in a single process in addition to reducing the operating temperature of a commercial photovoltaic solar panel and thus improves its energy efficiency. The PV module is installed in the northwest region of the state of São Paulo. The experimental apparatus had a single axis, azimuth solar tracking system; the output voltage and current of the panel were measured to quantify the power produced taking into account different operating conditions. All tests were carried out in loco using a commercial photovoltaic panel, always taking into account the weather conditions of the day. Solar tracking increases the energy generated by one day of the month by 45.5% compared to a fixed system. The temperature of the module with a thermally insulated back sheet was 15° C to 20° C hotter than a non-insulated panel, which implies energy losses of the order of 7.6%. The serpentine type heat exchanger, using deionized water, did not show satisfactory performance when cooling the photovoltaic module due to the significant thermal resistance of contact with the rear face of the module. Theoretical analysis showed errors of less than 10% compared to t... (Complete abstract click electronic access below) / Mestre

The aim of the master’s work is to assess the wind-power development prospects andproceeding therefrom assume scenarios of the wind-power development in Belarus until 2020 reasoning from the situations and tendencies common to both the national and world powerindustry. In my master’s work I have referred to ХХI-century current problems: procuring energypreparedness of the Republic of Belarus and reducing the anthropogenic impact on thebiosphere and reducing impact on the climate. For Belarus characteristic is a variety ofenvironmental challenges. For instance, one of the most urgent problems is Chernobyldisaster aftermath which affected Belarus to a very great extent. In my opinion some of these global problems may be partially solved by way of usingalternative energy sources, specifically the wind-power engineering. Such a narrow enough notion as the prediction of the wind-power engineering development inBelarus is described in my work by way of so deep and wide analysis of issues dealing withthe wind-power engineering development and prediction: the encyclical analysis of the stateand development of the power industry in its entirety in Belarus and how to reach energypreparedness at the time when effects of the finance-and-economic crisis are currently addedto other negative factors. It has been done specially for the purpose of making such an accurate prediction as possiblehaving analyzed the whole range of interrelated problems. I pitched upon the prediction of the development of the wind-power engineering preciselyuntil 2020 since I’d like to be tied to the basic document: “the National Strategy ofSustainable Social-and-Economic Development of the Republic of Belarus for a Period until2020”. In my work I have analyzed a possibility and horizons of developing the power industry inBelarus based on sustainable development principles. I have proved a capability andprofitability of developing renewable energy sources in Belarus. And the main emphasis wason considering the wind-power engineering. For Belarusian conditions there has beenproposed an optimum alternative of the integrated approach to developing the wind-powerengineering, i.e. joint using the wind-power engineering with other renewable and exhaustibleenergy sources. In this manner there has been refuted an opinion generally held that the windpower engineering development in Belarus is prospectless. In so doing the author, prior to turning to a major issue of the work: the prospects ofdeveloping the wind-power engineering in the Republic of Belarus, has given an estimate ofworld reserves of fuel resources and drawn up the following conclusions: deposits of fossilfuels are depleting and, consequently, the cost of mining operations will grow. Due to the factthat the main extraction of power resources is shifted to extreme regions the cost of conveying energy products is growing. Belarus has to import deficient power resources. Recently the price for Russian energy products for Belarus has grown dramatically. I have also approached the issue of expediency of building an atomic power station in Belarus. The prospects and consequences of using unconventional renewable energy sources in theRepublic of Belarus (with no wind-power engineering) are considered in all their aspectsfollowed by a detailed consideration of the prospects of developing the wind-powerengineering in the Republic of Belarus. Based on the above data there have been proposed two scenarios of developing the wind power engineering in Belarus: Scenario 1 «Unsustainable» and Scenario 2, which I called «Middle way to sustainable energy engineering». / Syftet med magister-arbetet är att bedöma vindkraftverkens utvecklingsmöjligheter och därifrån anta scenarier för vindkraftutvecklingen i Vitryssland till 2020, genom resonemang från de situationer och tendenser som är gemensamma för både nationella och internationella kraftindustrin. I mitt magister-arbete har jag hänvisat till 2000-talets nuvarande problem: att skaffa energisäkerhet i Republiken Vitryssland, minska effekterna av mänsklighetens påverkan på biosfären och minska påverkan på klimatet. Vitryssland kännetecknas av en rad olika utmaningar på miljöområdet. Till exempel är en av de mest akuta problemen Tjernobylkatastrofens efterdyningar som påverkade Vitryssland i mycket stor utsträckning. Min åsikt är att en del av dessa globala problem kan delvis lösas genom att använda alternativa energikällor, särskilt vindkraft-tekniken. Ett sådant specifierat begrepp som förutsägelsen av vindkraftteknikens utveckling i Vitryssland beskrivs i mitt arbete i form av en djup och bred analys av frågor som handlar om vindkraftteknikens utveckling och prognoser: Analysen av läget och utvecklingen av kraftindustrin i sin helhet i Vitryssland och hur man når energi-säkerhet när effekterna av finanskrisen för närvarande läggs till andra negativa faktorer. Det har gjorts speciellt för att göra en sådan precis förutsägelse som möjligt genom att ha analyserat hela raden av sammanhängande problem. Jag fokuserade på prognoser om utvecklingen av vindkraft-teknik innan 2020 eftersom jag vill vara bunden till det grundläggande dokument: ”den nationella strategin för hållbar socialoch ekonomisk utveckling i Vitryssland under en period fram till 2020”. I mitt arbete har jag analyserat en mängd olika möjlighet för att utveckla kraftindustrin i Vitryssland som bygger på principerna för hållbar utveckling. Jag har visat att det går att utveckla förnybara energikällor i Vitryssland, som är både kapabla och lönsamma. Med sikte på att använda sig av vindkraft-tekniken. För de vitryska förhållandena har det föreslagits ett optimalt alternativ för den integrerade strategin för att utveckla vindkraft-tekniken, dvs gemensamt med hjälp av vindkraft-teknik och med andra förnybara och icke förnybara energikällor. På detta sätt har det finns det en allmän åsikt angående vindkraft-teknikens utveckling i Vitryssland, som säger att det inte finns några direkta förutsättningar för denna typ av energi. Därigenom har författaren, innan upptagandet av huvud frågan i arbetet:,utsikterna att utveckla vindkraft teknik i Republiken Vitryssland, gjort en beräkning av världens reserver av bränsle-resurser och kommit fram till följande slutsatser: depåerna av fossila bränslen håller på att ta slut och därmed kommer kostnaderna för utvinning att växa. På grund av det faktum att huvuddelen av utvinningen av bränsle flyttas till extrema regioner så kommer kostnaden för att tillhandahålla energiprodukter växa. Vitryssland måste importera bristfälligt bränsle. Nyligen har priset för ryska energiprodukter för Vitryssland ökat dramatiskt. Jag har också tagit upp frågan om lämpligheten av att bygga ett kärnkraftverk i Vitryssland. Förutsättningarna och konsekvenserna av att använda okonventionella förnybara energikällor bedömning av möjligheterna att utveckla vindkraft tekniken i Vitryssland. Baserat på ovanstående data har det lagts fram två scenarier för utvecklandet av vindkrafttekniken i Vitryssland: Scenario 1 «Ohållbart» och Scenario 2, som jag kallade «Vägen mellan hållbar energi-teknologi».

Este trabalho estuda a interação entre os métodos anti-ilhamento aplicados em sistemas fotovoltaicos residenciais, operando simultaneamente em uma rede de distribuição de baixa tensão. Os sistemas fotovoltaicos em geral interagem entre si, com a rede de distribuição da concessionária e com outras fontes de geração distribuída. Uma consequência importante dessa interação é a ocorrência do ilhamento, que acontece quando as fontes de geração distribuída fornecem energia ao sistema elétrico de potência mesmo quando esta se encontra eletricamente isolada do sistema elétrico principal. A função anti-ilhamento é uma proteção extremamente importante, devendo estar presente em todos os sistemas de geração distribuída. Atualmente, são encontradas diversas técnicas na literatura. Muitas delas oferecem proteção adequada quando um inversor está conectado à linha de distribuição, mas podem falhar quando dois ou mais funcionam simultaneamente, conectados juntos ou próximos entre si. Dois destes métodos são analisados detalhadamente nesse estudo, avaliados em uma rede de distribuição residencial de baixa tensão. Os resultados obtidos mostram que a influência de um método sobre o outro é dependente da predominância de cada um deles dentro do sistema elétrico. Contudo, nas condições analisadas o ilhamento foi detectado dentro do limite máximo estabelecido pelas normas pertinentes. / This work studies the interaction between islanding detection methods applied in residential photovoltaic systems, operating simultaneously in a low voltage distribution network. Photovoltaic systems, in general, interact with themselves, with the utility grid and other distributed generation sources. An important consequence of this interaction is the islanding occurrence, which happens when distributed generation sources supply energy to the electrical power system even when it is electrically isolated from the main electrical system. The anti-islanding function is an extremely important protection, and should be present in all distributed generation systems. Actually, many techniques are found in the literature. Most of them provide suitable protection when one inverter is connected to the distribution line, but can fail when two or more work simultaneously, connected at the same point or close to each other. Two of these methods are analyzed in detail in this study and evaluated in a residential low voltage distribution line. The obtained results show that the influence of a method over another one is dependent of the predominance of each one within the electrical system. However, in the analyzed condition the islanding was detected within the maximum allowed time established by applicable rules.

Este trabalho estuda a interação entre os métodos anti-ilhamento aplicados em sistemas fotovoltaicos residenciais, operando simultaneamente em uma rede de distribuição de baixa tensão. Os sistemas fotovoltaicos em geral interagem entre si, com a rede de distribuição da concessionária e com outras fontes de geração distribuída. Uma consequência importante dessa interação é a ocorrência do ilhamento, que acontece quando as fontes de geração distribuída fornecem energia ao sistema elétrico de potência mesmo quando esta se encontra eletricamente isolada do sistema elétrico principal. A função anti-ilhamento é uma proteção extremamente importante, devendo estar presente em todos os sistemas de geração distribuída. Atualmente, são encontradas diversas técnicas na literatura. Muitas delas oferecem proteção adequada quando um inversor está conectado à linha de distribuição, mas podem falhar quando dois ou mais funcionam simultaneamente, conectados juntos ou próximos entre si. Dois destes métodos são analisados detalhadamente nesse estudo, avaliados em uma rede de distribuição residencial de baixa tensão. Os resultados obtidos mostram que a influência de um método sobre o outro é dependente da predominância de cada um deles dentro do sistema elétrico. Contudo, nas condições analisadas o ilhamento foi detectado dentro do limite máximo estabelecido pelas normas pertinentes. / This work studies the interaction between islanding detection methods applied in residential photovoltaic systems, operating simultaneously in a low voltage distribution network. Photovoltaic systems, in general, interact with themselves, with the utility grid and other distributed generation sources. An important consequence of this interaction is the islanding occurrence, which happens when distributed generation sources supply energy to the electrical power system even when it is electrically isolated from the main electrical system. The anti-islanding function is an extremely important protection, and should be present in all distributed generation systems. Actually, many techniques are found in the literature. Most of them provide suitable protection when one inverter is connected to the distribution line, but can fail when two or more work simultaneously, connected at the same point or close to each other. Two of these methods are analyzed in detail in this study and evaluated in a residential low voltage distribution line. The obtained results show that the influence of a method over another one is dependent of the predominance of each one within the electrical system. However, in the analyzed condition the islanding was detected within the maximum allowed time established by applicable rules.

The subject of the thesis is the use of solar thermal technology for the production of low-potential heat. The theoretical part is focus in the solar technology, variants of passive use of solar energy. Describes in detail the solar facades, it's classification in terms of basic criteria. Applications on the project forced ventilation in administrative buildings, installation of solar facade. The work also includes an experiment that deals with the thermal behavior of the air collector.

The aim of the thesis is a design of the best energy measures for a family house. At first there is carried out an energy assessment of the building. According to results of that survey there are drawn up some variants of measures. Furthermore, based on energy assessment results there is elaborated a project for reconstruction of the heating.