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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.
41

Egenproducerad solel i ett småhusområde

Englund, Anders, Sundholm, Sara January 2010 (has links)
Sverige ska år 2020 ha en energiförsörjning bestående av 50 % förnybara energikällor. Den viktigaste källan till förnybar energi är solen. Solel är dock en dyr investering idag och gällande regelverk försvårar möjligheterna till att tillgodoräkna sig egenproducerad el. Byggföretaget JM bygger redan hus med låg energianvändning. Ett sätt att bidra till ett förnybart energianvändande är att installera system som producerar egen el till husen. Detta arbete har genomförts för att undersöka om solel kan komma att bli en konkurrenskraftig produkt att erbjuda JM:s husköpare. I arbetet har ett specifikt område och en av företagets typhusmodeller studerats. Dagens solcellsteknik har studerats och ett system för huset har komponerats. Det finns ett flertal typer av solceller men i detta arbete har polykristallina solceller valts utifrån det offertförslag som legat till grund för arbetet. För att kunna dimensionera anläggningen har placering, orientering och solvinklar undersökts. Genom att välja en anläggning har investeringskalkyler och simuleringar kunnat utföras för ett par olika scenarier. Samtliga scenarier bygger på nätanslutna system men skiljer sig mellan dagens regelverk och ett framtida scenario med nettodebitering, dvs. kvittning av egenproducerad el och köpt el. Från JM:s sida har det funnits önskemål om att studera hur ett bostadsområde skulle kunna dela på en solcellsanläggning genom ett samfällt system. Den samfällda anläggningen har dimensionerats utifrån fullgott solläge. I aktuellt område innebar det att 16 av 35 hus är lämpligt placerade mot solen, detta kan dock skilja mellan olika områden. Resultatet visar att en investering i solel är svår att försvara idag. Med ett statligt stöd på 60 % är återbetalningstiden likväl 20 år. Med ett förändrat regelverk och ett långsiktigt stöd skulle det kunna bli ekonomiskt lönsamt. Genom att solcellstekniken blir billigare och elpriset stiger förbättras läget för solelen. Investeringskostnaden blir lägre per person och öppnar därmed upp för fler investerare.
42

Optimization of energy storage use for solar applications

Ek, Ludvig, Ottosson, Tim January 2018 (has links)
Energy storage systems is very useful to use in solar panel systems to save money, but also tobe more environment-friendly. The project was given by the solar energy companyPerpetuum Automobile (PPAM) and the project is for their customer, the condominiumcompound Ekoxen. The task is to make a energy regulation for Ekoxen's energy storage sothey can save more money. The energy storage primary task is to shave the top-peaks of theconsumption for Ekoxen. Which means that the battery will supply the household instead forthe three-phase grid. This will make the electric bill for Ekoxen cheaper. Thesimulation/analysis of the energy regulation is done in a spreadsheet tool, where one partworks as a Time-of-Use program and the other work as a modbus feature. Time-of-Use is aweb-based program for PV systems with battery storage, where time-periods can be set toaffect the battery behavior. The modbus feature simulates a system where an algorithm can beimplemented. The results will show that the time-periods for charging the battery with theTime-of-Use program needs to be changed two times per year. One time for the summermonths and a second time for the rest of the months. The results will also show that themodbus feature is better on peak shaving than the time-of-use program.
43

Determinação da eficiência de um coletor solar plano com aletas de vidro

Bentivenha, Luiz Carlos [UNESP] 25 January 2005 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-01-25Bitstream added on 2014-06-13T19:11:16Z : No. of bitstreams: 1 bentivenha_lc_me_botfca.pdf: 1314612 bytes, checksum: 253e63a1300e0c3946bf45baca1a4fba (MD5) / Universidade Estadual Paulista (UNESP) / Os coletores solares comumente utilizados no aquecimento de água, para o consumo doméstico, possuem a placa de aquecimento solar plana do tipo chapa - tubo. Devido à crescente utilização desses equipamentos, buscou-se, através deste trabalho, modificar um equipamento convencional, o qual recebeu, na placa solar, aletas de vidro, instaladas no plano vertical em relação à tampa de vidro, dividindo a mesma em diversas áreas, propiciando um aumento, tanto da reflexão dos raios infravermelhos em seu interior, quanto do efeito estufa. O objetivo do ensaio foi estudar o comportamento térmico desse equipamento, trabalhando a determinada vazão e obtendo as temperaturas com o emprego de termopares instalados em vários pontos do sistema, buscando a determinação da eficiência térmica da placa solar modificada. Para a determinação da eficiência, foram considerados o calor útil, o calor absorvido e as perdas de calor. As equações empregadas na determinação da eficiência térmica foram trabalhadas no programa Excel.Verificou-se que o equipamento apresentou um bom rendimento, atendendo as especificações definidas pelo INMETRO. A temperatura média de saída da água do equipamento apresentou valor superior a de equipamento similar, o mesmo não ocorreu com seu rendimento, embora as diferenças registradas tenham sido pequenas. A eficiência do equipamento não depende apenas dos parâmetros do projeto, mas também de outros fatores que levam a perda de energia. / The solar collectors commonly used in the water heating for domestic consumption possess the flat plate solar heating of plate type - tube. Due to increasing applications of those equipments the purpose was to modify the conventional, which received glass fins in the solar plate, installed in the vertical plan in relation to the glass cover, dividing the same in several areas, enabling reflection increase of the infrared rays in its interior as well as greenhouse effect. The thermal performance of the equipment has been studied analyzing the certain flow and obtaining the temperatures with the thermopairs installed in several points of the system and determining the thermal efficiency of the modified solar plate. The useful heat, the absorbed heat and the losses of heat were considered. The equations of the thermal efficiency were obtained in the Excel program. The equipment presented a good performance according to INMETRO specifications. The medium temperature of the water exit presented superior value when compared to a similar equipment. The same didn't occur with its performance, although the registered differences have been small. The efficiency of the equipment doesn't depend only on the parameters of the project, but also on other factors which lead to energy loss.
44

Determinação da eficiência de um coletor solar plano com aletas de vidro /

Bentivenha, Luiz Carlos, 1953- January 2005 (has links)
Orientador: José Roberto Corrêa Saglietti / Banca: Angelo Cataneo / Banca: Alessandro Torres Campos / Resumo: Os coletores solares comumente utilizados no aquecimento de água, para o consumo doméstico, possuem a placa de aquecimento solar plana do tipo chapa - tubo. Devido à crescente utilização desses equipamentos, buscou-se, através deste trabalho, modificar um equipamento convencional, o qual recebeu, na placa solar, aletas de vidro, instaladas no plano vertical em relação à tampa de vidro, dividindo a mesma em diversas áreas, propiciando um aumento, tanto da reflexão dos raios infravermelhos em seu interior, quanto do efeito estufa. O objetivo do ensaio foi estudar o comportamento térmico desse equipamento, trabalhando a determinada vazão e obtendo as temperaturas com o emprego de termopares instalados em vários pontos do sistema, buscando a determinação da eficiência térmica da placa solar modificada. Para a determinação da eficiência, foram considerados o calor útil, o calor absorvido e as perdas de calor. As equações empregadas na determinação da eficiência térmica foram trabalhadas no programa Excel.Verificou-se que o equipamento apresentou um bom rendimento, atendendo as especificações definidas pelo INMETRO. A temperatura média de saída da água do equipamento apresentou valor superior a de equipamento similar, o mesmo não ocorreu com seu rendimento, embora as diferenças registradas tenham sido pequenas. A eficiência do equipamento não depende apenas dos parâmetros do projeto, mas também de outros fatores que levam a perda de energia. / Abstract: The solar collectors commonly used in the water heating for domestic consumption possess the flat plate solar heating of plate type - tube. Due to increasing applications of those equipments the purpose was to modify the conventional, which received glass fins in the solar plate, installed in the vertical plan in relation to the glass cover, dividing the same in several areas, enabling reflection increase of the infrared rays in its interior as well as greenhouse effect. The thermal performance of the equipment has been studied analyzing the certain flow and obtaining the temperatures with the thermopairs installed in several points of the system and determining the thermal efficiency of the modified solar plate. The useful heat, the absorbed heat and the losses of heat were considered. The equations of the thermal efficiency were obtained in the Excel program. The equipment presented a good performance according to INMETRO specifications. The medium temperature of the water exit presented superior value when compared to a similar equipment. The same didn't occur with its performance, although the registered differences have been small. The efficiency of the equipment doesn't depend only on the parameters of the project, but also on other factors which lead to energy loss. / Mestre
45

Etude d'un capteur solaire hybride avec concentrateur holographique du rayonnement solaire / Study of a hybrid solar collector with holographic concentrator of solar radiation

Iurevych, Olena 07 July 2015 (has links)
Les besoins énergétiques du monde entier augmentent de plus en plus et parmi les sources en énergie renouvelable, l'énergie solaire connaît actuellement un très fort développement. Une des voies en énergie solaire est la filière utilisant des panneaux solaires hybrides qui produisent à la fois de l'électricité et de la chaleur. Le marché des capteurs hybrides en présence ou non de concentrateur et leurs caractéristiques sont présentés. Dans la thèse, on a étudié un capteur hybride associé avec un concentrateur holographique du rayonnement solaire. Ce concentrateur permet de séparer la partie visible utilisée par les cellules photovoltaïques de celle infrarouge, absorbée par l'échangeur thermique. Les différents éléments du capteur et leur fonctionnement sont décrits. Les caractéristiques du capteur et son efficacité dépendent des paramètres optiques et thermiques de ses éléments. Ces paramètres (facteurs de transmission, de réflexion, d'absorption, émissivité) ont été déterminés expérimentalement (CERTES IUT Sénart, CEMHTI Orléans, Université Blaise Pascal Clermont-Ferrand). Les résultats obtenus ont été utilisés dans une modélisation stationnaire et monodimensionnelle des échanges thermiques pour deux configurations différents (avec deux plaques en polycarbonate et avec une plaque en polycarbonate et une lame d'air). La modélisation introduit les effets radiatifs, conductifs et l'absorption du rayonnement en volume. Les profils thermiques et les rendements électriques et thermiques obtenus montrent l'efficacité d'un capteur solaire hybride avec concentrateur holographique. / The energy requirements worldwide are increasing more and among renewable energy sources, solar energy is exhibiting a very strong growth. Solar hybrid panels that produce both electricity and heat is currently a very promising way. The market for hybrid solar panel with and without concentrator and their characteristics are presented. In the thesis, a hybrid solar panel associated with a holographic concentrator solar radiation is studied. This concentrator separates the visible range used in the photovoltaic cells of the infrared range absorbed by the heat exchanger. The elements of the panel are described. The sensor characteristics and effectiveness depend on the optical and thermal parameters of its elements. These parameters (transmission factors, reflection, absorption, emissivity) were determined experimentally (CERTES IUT Sénart, CEMHTI Orleans, University Blaise Pascal Clermont-Ferrand). The results were obtained in a stationary and dimensional modelling heat exchanges for two different configurations (with two polycarbonate plates with a polycarbonate plate and an air). The model introduces radiative effects, conduction and radiation absorption by volume. The thermal profiles, and electrical and thermal efficiencies obtained show the effectiveness of a hybrid solar collector with holographic concentrator.
46

Carteras de cuero vegetal de shiringa – Vert Clair / Vert Clair - Shiringa's leder's hand bag

Bazan Guzman, Rudy Alejandro, Burgos Cruzado, Aracelly Giovana, Chavez Podesta, Diane Maite, Flores Reynoso, Nataly Maria Jesus, Salleres Capellino, Mario Carlos 21 July 2020 (has links)
En la actualidad, los consumidores en el sector de manufactura en cuero para diferentes productos van revolucionando la moda, creando productos sostenibles con procesos y materiales alternativos como el cuero vegetal en reemplazo del cuero natural o bovino. Ante ello, nace la idea de presentar un modelo de negocio sobre carteras a base de cuero vegetal, el cual será obtenido por la Asociación de productores de Shiringa ubicada en Condorcanqui - Amazonas. Asimismo, se incorpora un cargador solar como valor adicional que va acorde a la iniciativa de realizar un proyecto amigable con el ambiente. Esta propuesta, lleva como nombre Vert Clair y considera como grupo objetivo a mujeres modernas y sofisticadas entre 18 y 40 años que gustan estar a la moda. Por ende, para probar la aceptación de este proyecto se ha realizado diversas investigaciones y experimentos que permitan dar validez a este modelo de negocio, para así presentar los planes de acción en las áreas pertinente, con la finalidad de obtener una aliciente rentabilidad y a la vez también, dar a conocer al mercado e industria peruana una nueva alternativa que transforme la moda. / Nowadays, consumers in the leather manufacturing sector for different products are revolutionizing fashion, creating sustainable products with alternative processes and materials such as vegetable leather to replace natural or bovine leather. Given this, the idea was born to present a business model on wallets based on vegetable leather, which will be obtained by the Association of producers of Shiringa located in Condorcanqui - Amazonas. Also, a solar panel is incorporated as additional value that goes according with the initiative to make an environmentally friendly project. This proposal is named Vert Clair and considers as a target group modern and sophisticated woman between 18 and 40 years old who like to be fashionable. Therefore, to test the acceptance of this project, various investigations and experiments have been carried out to validate this business model, to present the action plans in the relevant areas, in order to obtain an attractive profitability and at the same time also, to make known to the Peruvian market and industry a new alternative that transforms fashion. / Trabajo de investigación
47

PUERTO RICO POWER SYSTEM TRANSITION TO RENEWABLE ENERGY

Sofia Paola Espinell Gonzalez (9970334) 14 January 2021 (has links)
<div> <div> <div> <p>Puerto Rico’s lack of effective and affordable energy substitutes after Hurricane Maria resulted in a mortality increase of 4,970 residents (Verma, Murray, and Mamdani, 2018). Puerto Rico’s Island dependency on electric power and no energy substitutes available have provoked a risk to human life after catastrophic events. The problem was measured by comparing Puerto Rico’s reliance on fossil fuels with accessible and economical renewable energy options. Solar photovoltaic (PV) technologies are the optimum alternative to transition from fossil fuel usage to renewable energy. Previous research has demonstrated the impact of using solar panels instead of an electric grid due to the constant solar radiation throughout the year. The analyzed data and projections showed a reduction in fossil fuels and carbon dioxide emissions by implementing solar photovoltaic technologies. The installation of PV systems in landfills, household roofs and transitioning to solar public lighting positively impacts the atmosphere carbon dioxide emissions. </p> </div> </div> </div>
48

Polohové řízení solárního panelu s optimalizací energetické účinnosti / Positioner for Solar Panel with Power Efficiency Optimizing

Kreysa, Karel January 2011 (has links)
This thesis is focused on design and prototyping of solar panel position control system for an obtaining of the maxima renewable energy from sun. In this thesis, various ways of solar panel positioning are considered and analyzed. Consequently, a construction arrangement of the positioner is presented. It is mechanically adapted to obtain the maximum efficiency in typical environment corresponding with the Central European geographical latitude. Different methods of sun monitoring are considered and analyzed. On the basis of this analysis, a proper prototype of sun monitor for exact positioning with disturbance filtering has been constructed. Following part of work is devoted to stable, fully automated, control subsystem for reliable functionality of solar system. A suitable microprocessor with a robust firmware has been implemented to this control unit. Finally, system parameters measurement and closing analysis of gained renewable energy and backflow computation is presented in the end of this diploma thesis.
49

Cargador Portátil Ecológico MAX - E / MAX -E Eco Friendly Portable Charger

Acosta Valverde, Melanie Araceli, Andrade Mariños, Joan Ayrton, Linares Castillos, Diego Alonso, Ortiz Chamochumbi, Renzo, Vásquez Calderón, John Erick 31 July 2020 (has links)
El presente proyecto es un cargador solar ecológico que puede ser transportado en todo momento debido a su tamaño compacto y su poco peso de 150 gramos. Además, almacena la energía del sol y la luz led para luego cargar tu dispositivo en cualquier momento. Se desarrolla su viabilidad en base a una investigación realizada a hombres y mujeres de 18 a 39 años de los niveles socioeconómicos A, B y C. Por lo tanto, el análisis permite identificar a un grupo de personas que necesitan cargar su celular en momentos importantes durante el día pero que no encuentran lugar donde conectarlo o no tienen un cargador. Para validar la solución se utilizó un prototipo del producto el cual fue presentado al público y especialistas para que salga al mercado. Por último, se realizó un concierge para calcular la intención de compra del producto y proyectar sus estados financieros, los cuales, están respaldados por pertinentes desarrollos estratégicos que llevan a cabo un plan de negocio.
50

Simulations of energy efficient windows in a historical building located in mid-Sweden

Medrano Eraso, Iñigo January 2023 (has links)
Amorphous silicon photovoltaic windows intend to not only improve thethermal bridge that windows represent but also to collect energy from theradiation incident on the windows themselves. This kind of windows can beapplied anywhere, however to maximize the benefit these can bring it isrecommended for sun-oriented façades. This research aims to investigate theimpacts that this type of windows can have on the energy performance andthermal comfort of a three-story historical stone building in the cold climateof Sweden using the simulation software IDA ICE. The model used for thesimulations had previously been developed and tested in other researches thatinvolved this same building. This research shows that the yearly energyconsumption for the townhall can be reduced down to 280000 kWh,representing a reduction of 5000 kWh compared to the base model, if theHigh transparency windows are applied, representing a reduction of 1,7%.The use of any of the four proposed windows has shown to increase thepercentage of best comfort hours by at least 5% and lowers the percentage ofunacceptable comfort hours at least by a 10%, even having cases with 0 hoursat this comfort level. The upper level of the South façade would be able toprovide the building with 800 kWh yearly, being the level with the highestenergy collection due to having more windows. Approximately every windowcould collect around 90 kWh yearly, which represents 20% of what a solarpanel of the same area correctly oriented could obtain in the same period oftime. Thus, the amorphous silicon photovoltaic windows do not seem to bethe best change despite offering a very promising thermal comfort. Theeconomical viability of this project is what prevents it from being feasiblesince the energy saving/obtaining characteristics are not of great magnitude.

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