Dissertations / Theses on the topic 'Solar energy'

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1

Золотова, Світлана Григорівна, Светлана Григорьевна Золотова, Svitlana Hryhorivna Zolotova, and T. V. Konoplenko. "Energy producing: solar energy." Thesis, Видавництво СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/13440.

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2

Bafana, Ramzi, and Zain Zulfiqar. "Solar Energy." Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2079.

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This thesis is about Photovoltaic (PV) cells and its stresses in various directions by calculating the power generated using solar cells under different conditions to improve its efficiency. Our research studies found that using multi-junction cells with larger substrates can increase the efficiency to some extent which in practice is limited to 43 percent. The experiment was conducted using ten solar cells each with an area of 20.9〖cm〗 ^2, where each cell gives 0.5 V and 0.4 A and a 1.25 Ω resistor was used. The cells were connected in series. Once, the PV cells were fixed horizontally and the other time tested in tilted position under same outdoor condition. The purpose of testing PV cells was to investigate the efficiency under above mentioned conditions. The data collected from the readings was used in calculation, and we have obtained from the calculations that horizontally fixed cells gave 4.8 percent efficiency whereas tilted cells gave 6.6 percent efficiency. Hence, the ratio showed that fixed cells produced 37.5 percent more power compared to horizontally fixed cells. Our other experiment consisted of testing PV cells under different temperature conditions that was done using a freezer and an oven for temperature variation and a tungsten bulb was used as a light source. The purpose of performing this experiment was to investigate how the efficiency of PV cells is affected under extreme conditions. Part of our thesis was also including studies and analysis of produced energy by the solar panel installed on the roof of “BTH” building in Karlskrona, Sweden. The data consisted of energy produced from February up to August 2014. The investigation also included finding the highest produced energy during these months. We have found that the highest energy was generated on the 1st of July which was 12.86 kWh. Furthermore, we went deep into investigation of the 1st of July to know exactly which hour of that day the highest energy was produced. The data showed that the highest produced energy was at 12:19 and 13:19 which was 2.03 kWh.
Ramzi: +46723231353, +966561993488 Zain:
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3

Yeremenko, А. "Solar energy is an energy alternative source." Thesis, Sumy State University, 2017. http://essuir.sumdu.edu.ua/handle/123456789/62568.

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Our relationship with the environment is bilateral. If we want to live in clear world that takes care about us we must take care about the environment. It is evident that healthy population and high quality of life is possible only in healthy environment.
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4

Maples, David William. "The Solar Energy Tracker." Thesis, University of Canterbury. Electrical and Computer Engineering, 2008. http://hdl.handle.net/10092/4420.

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Reference is increasingly being made towards the need for the world to find new and renewable forms of energy, especially for electric power generation, but also for space heating and the heating of water. Solar energy is one of the cheapest forms of renewable energy available and is so far one of the most underutilised resources. One contribution makes reference to the way forward as being ‘using concentrating solar power which uses parabolic mirrors to focus the solar heat (energy) and generate steam to drive electric generators’ as is currently happening in the utility power marketplace in the USA. This thesis deals with the issues surrounding the original development of a two axis solar energy tracking system (SET) in 1997. The subsequent redesign, development and upgrade, undertaken from 2002 to 2006, with its performance and efficiency being measured in 2006 and 2007 using a specially configured measurement and recording system. A Solar Energy Tracker (SET) is designed to track the sun moving in two axes, reflecting the solar radiation received on its mirrors to a target mounted at the end of a boom, at the focal point of the mirrors. In late 2005 and early 2006, a solar thermal hot water manufacturer and installer heard about the developments and requested some form of involvement, especially if Christchurch Polytechnic Institute of Technology (CPIT) provided research input and assisted in the further development and testing of solar thermal hot water systems. This sponsor offered two projects in 2006 and again in 2007. Other solar thermal hot water suppliers also requested involvement in the research and development being performed at CPIT, which led in August 2006, December 2006, June 2007 and December 2007, to a number of other solar thermal hot water and air wall systems being installed. Progressively, the roof of C block at CPIT has become full of solar thermal hot water systems and solar air wall systems, both of the conventional type and those with newer technologies at the core of their development. This thesis outlines the stages in the redesign and development of the SET, and the various stages in its testing, development and refinement up to its present form. The thesis chapters are written based around the mechanical and electrical design, the auto-tracking and daylight controls, the PLC (programmable logic controller) controller, the mirror and substrate testing, the SCADA (Supervisory Control And Data Acquisition) system, the testing and comparison with other domestic solar thermal hot water systems and finally the testing of the SET itself. It also details the future developments and outlines possible uses for the SET in its redefined form. With clean and polished mirrors the SET has proven itself capable of achieving a temperature rise across the target of 15 °C at a flow rate of 4 l/m. On some occasions this temperature rise can be in excess of 20 °C, but testing thus far, has shown this cannot be sustained for any worthwhile period of time (15-30 minutes). This translates to an efficiency of 5-10 % when related to an energy produced per twenty four hour time period. However, if the efficiency is calculated for the actual period of generation, ‘generation efficiency,’ then this figure rises to 24 %. An overview is given of associated solar thermal hot water and solar air wall system research and development (that is ongoing at CPIT) as well as the performance and efficiency graphs for the solar thermal hot water systems on test. No manufacturer’s, industry or brand trade names are mentioned, as this research is still confidential and commercially sensitive. However, the technology involved and characterised by each solar thermal system is recorded in a generic sense. The SET was originally developed with the purpose of heating hot water and today this is still the intent. The possible applications for this hot water are many and varied from electricity generation, space heating and further into developing or new industrial processes. The performances of the other domestic solar thermal hot water systems currently under test, are compared with the figures from the SET, with the maximum efficiency, presently available, being from an evacuated tube heat pipe system at up to 65 %, whereas traditional finned flat plate technologies have efficiencies after twelve months of up to 48 %.
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5

Parand, Foroutan. "Solar energy utilisation and evacuated tubular solar collectors." Thesis, Brunel University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292989.

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6

Bortolini, Marco. "Design, control and management of renewable energy plants and technologies." Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3422587.

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Nowadays, and even more in the next decades, the availability and easy-access to energy sources represent a crucial asset for the world development and the progress of people and nations. At the same time, the depletion of natural resources, together with the increase of the anthropic activity impact on the Earth ecosystem and climate, force communities and institutions, at all levels, to discuss and actuate different approaches to achieve the social and economic growth, based on the so-called sustainable development pattern. In such a scenario, renewable energy sources, i.e. solar, wind, hydro, biomass, geothermal, etc., certainly play a key role to join progress and attention to the environmental issues. The present Ph.D. dissertation focuses on such topics investigating strategies, methods and innovative approaches for the effective design, control and management of renewable energy plants and technologies. Specifically, the energy scenario is investigated from a global point of view proposing studies and optimization models highlighting the relevance and the potential impact of the major energy sources, both renewable and conventional. Such sources represent the elements of a big puzzle, i.e. the energy mix, in which their economic and environmental strengths should be emphasized minimizing the associated negative impacts and weaknesses. Among renewable sources, solar energy is of primary importance for availability, diffusion and potential impact. The present Ph.D. dissertation particularly investigates such a source presenting models, methods and prototypes to increase its relevance in the energy mix. The fundamentals of solar energy, together with innovative approaches to estimate the solar radiation components, are provided. Furthermore, the pioneering concentrating solar sector is deeply focused presenting the design, development and preliminary field-test of a bi-axial Fresnel solar photovoltaic/thermal (PV/T) concentrating prototype. Possible solar tracking strategies and control algorithms are, then, investigated describing a customized semi-automatic motion control platform, developed in LabViewTM programming environment. Finally, the last section, proposes an effective approach for the design of a solar simulator, the most frequently adopted device in solar optic laboratory tests. In conclusion, the present Ph.D. dissertation describes effective strategies for the renewable energy spread, considering their performances and their potential impact to achieve the ambitious challenge of a sustainable living planet.
Oggigiorno, ed in misura crescente nei prossimi decenni, la disponibilità e facilità di accesso alle fonti energetiche rappresenta un fattore determinante per lo sviluppo mondiale ed il progresso di popoli e nazioni. Parallelamente a ciò, il progressivo sfruttamento delle risorse naturali, unito all’aumento dell’impatto delle attività antropiche sull’ecosistema terrestre e sul clima, impongono a comunità ed istituzioni, ad ogni livello, un ripensamento e l’attuazione di differenti strategie per garantire lo sviluppo sociale ed economico attraverso il ricorso ad approcci basati sul concetto di sviluppo sostenibile. In questo contesto, le fonti energetiche rinnovabili, i.e. solare, eolica, idroelettrica, da biomasse, geotermica, ecc., assumono certamente un ruolo determinante per coniugare progresso ed attenzione alle tematiche ambientali. La presente Tesi di Dottorato si incentra su queste tematiche approfondendo strategie, metodi ed approcci innovativi per l’efficace progettazione, controllo e gestione di impianti e tecnologie per le energie rinnovabili. Nel dettaglio, lo scenario d’insieme delle fonti energetiche è analizzato con logica di sistema ed orientamento all’ottimizzazione globale proponendo studi e modelli che evidenzino l’importanza ed il potenziale delle principali risorse, rinnovabili e non, come elementi di un grande mosaico, i.e. il mix energetico globale, nel quale le potenzialità economiche ed ambientali di ogni risorsa sono enfatizzate minimizzando, nel contempo, gli impatti negativi e le rispettive debolezze. Tra le possibili fonti rinnovabili, la fonte solare assume primaria importanza per disponibilità, diffusione ed impatto potenziale. La presente Tesi di Dottorato analizza, in dettaglio, questa risorsa energetica presentando modelli, metodi ed impianti sviluppati per accrescere l’incidenza di questa risorsa nel mix energetico. Gli elementi ed aspetti fondamentali, insieme ad approcci innovativi per la stima delle componenti della radiazione solare, sono presentati nell’elaborato. Successivamente, l’innovativo settore della concentrazione solare è analizzato, in dettaglio, anche attraverso l’illustrazione delle scelte progettuali, lo sviluppo e la campagna sperimentale preliminare di un concentratore solare fotovoltaico/termico (PV/T) a lenti di Fresnel ed inseguimento biassiale. Nel seguito, vengono approfondite possibili strategie per l’inseguimento biassiale ed algoritmi di controllo, implementati in una piattaforma semi-automatizzata sviluppata in ambiente di programmazione grafica LabViewTM. L’ultima sezione propone, infine, un approccio per la progettazione di un simulatore solare, un dispositivo spesso adottato nei test di ottica solare. In conclusione, la presente Tesi di Dottorato, descrive una molteplicità di strategie orientate alla diffusione delle energie rinnovabili, con attenzione alle performance ed all’impatto potenziale che esse hanno verso il raggiungimento dell’obiettivo ambizioso di un sostenibile living planet.
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Varella, Fabiana Karla de Oliveira Martins. "Estimativa do indice de nacionalização dos sistemas fotovoltaicos no Brasil." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263003.

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Orientadores: Carla Kazue Nakao Cavaliero, Ennio Peres da Silva
Tese (doutorado) -Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: A Lei nº 10.438/02 estabeleceu o Programa de Incentivo às Fontes Alternativas de Energia Elétrica - PROINFA, único programa nacional a estimular as fontes renováveis alternativas, com o intuito de aumentar a participação da energia elétrica produzida por empreendimentos a partir das fontes eólica, pequenas centrais hidrelétricas - PCHs e biomassa no sistema interligado nacional. Posteriormente, o PROINFA foi revisado pela Lei nº 10.762/03 e alterou em sua regulamentação a obrigatoriedade de um índice mínimo de nacionalização de serviços e equipamentos, que em sua primeira etapa passou a corresponder a 60% do custo total da construção dos projetos contemplados. A energia solar fotovoltaica não foi contemplada pelo Programa, e o objetivo desta tese é estimar o índice de nacionalização para cada um dos três sistemas fotovoltaicos selecionados para estudo (sistema de bombeamento de água, sistema de eletrificação rural e sistema conectado à rede elétrica). Para elaboração desse cálculo foi efetuada uma adaptação da metodologia utilizada pelo PROINFA e considerados somente os custos dos principais equipamentos e não dos serviços. Os resultados obtidos permitiram concluir que os sistemas de bombeamento de água e de eletrificação rural são sistemas que 5% e 35%, respectivamente, dos seus equipamentos já são disponibilizados pela indústria nacional. mesmo não ocorre com os sistemas fotovoltaicos conectados à rede elétrica, que atualmente tem 100% dos seus principais equipamentos importados
Abstract: The Law nº 10.438/02 established the Program of Incentives for Alternative Electric Power Sources - PROINFA, which is the only national program aimed to foster alternative renewable energy sources and to increase the share of electric energy production from enterprises based on wind power, small hydropower plants and biomass in the interconnected national power grid. PROINFA was later modified by the Law nº 10.762/03 which revised the regulation imposing a minimum nationalization index of services and equipment that in its first stage corresponded to 60% of the total cost of the selected projects. Solar photovoltaic power was not included in PROINFA and because of that the objective of this thesis is to estimate the nationalization index of each of the following photovoltaic systems selected for the study: water pumping PV system, rural electrification PV system and grid-connected PV system. In order to carry out the calculations, the methodology used at PROINFA was adapted and only the costs of the key equipment, not the services, were considered. The results led to the conclusion that the water pumping and the rural electrification systems are those in which 5% and 35%, respectively, equipment is already made available by the national industry. The same is not verified for the grid-connected PV systems in which 100% of the key equipment is imported
Doutorado
Doutor em Planejamento de Sistemas Energéticos
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8

Mattos, Sérgio Ricardo de [UNESP]. "Análise do rendimento térmico do aquecedor solar parabólico cilíndrico." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/99302.

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Este aquecedor solar foi construído em uma estrutura metálica, que tem um revestimento de polietileno reflexivo parabólico cilíndrico, onde no foco da parábola passa uma serpentina com sete tubos em cobre de 9,5 mm e o projeto foi desenvolvido para obter temperaturas mais elevadas do que os aquecedores planos. O objetivo desta dissertação foi atingir temperaturas mais altas na fase líquida. As temperaturas alcançadas foram obtidas utilizando uma densidade de potência solar que variou entre (1.000±10) W/m2, nas vazões de: 66, 54, 42, 30, 27, 24, 21, 18, 15, 12 e 9 litros por hora. A máxima temperatura atingida utilizando-se a vazão de nove litros por hora foi de 71°C, permitindo uma diferença de temperatura, em relação a temperatura ambiente de 43°C. A máxima vazão utilizada no aquecedor solar parabólico cilíndrico foi de 66 litros por hora e obteve-se uma temperatura de 38°C, sendo a diferença em relação à temperatura ambiente de 6°C. Assim com o desenvolvimento do aquecedor solar parabólico cilíndrico obtiveram-se temperaturas maiores em uma área de captação menor, do que em aquecedor convencionais planos e com rendimentos superiores a 70% em sua maior faixa de operação
This solar heater is constructed of a metallic structure, which has a polyethylene coating reflective parabolic cylindrical, where the focus of the parable is a serpentine seven copper pipes of 9.5 mm and the project was designed to obtain higher temperatures than the heaters plans and the objective of this thesis was to reach higher temperatures in the liquid phase. The temperatures reached were obtained using a solar power density ranged from (1000±10) W/m2, the flow rates: 66, 54, 42, 30, 27, 24, 21, 18, 15, 12 and 9 liters per hour. The maximum temperature reached by using the flow of nine liters per hour was 71°C, allowing a temperature difference in relation to ambient temperature of 43°C. The maximum flow rate used in the cylindrical parabolic solar heater was 66 liters per hour and obtained a temperature of 38°C, and the difference in the ambient temperature of 6°C. So with the development of a cylindrical parabolic solar heater temperatures were obtained in a larger area smaller than in conventional heating plans and with performance up to 70% on the higher range of operation
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Yang, Sun. "Solar Energy Control System Design." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-141489.

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This thesis covers design, simulation and implementation of a solar energy control system for an on grid energy storage device. The design covers several control methods such as energy balance control, operating mode switching and data exchange. A genetic algorithm was designed to optimize the control system parameters design, and the algorithm's simulation and real time operating system implementation showed comparable results. The control system was implemented to connect a power supply to the grid. The power supply simulated a solar panel and connected to an electrical grid via Energy Hub equipment, and the energy transfer characteristics of designed control system were tested. The results showed that the selected algorithm matches the target performance criteria.
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Hofker, Gerrit. "Desiccant cooling with solar energy." Thesis, De Montfort University, 2001. http://hdl.handle.net/2086/4274.

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11

Van, Zyl GHC. "Solar energy for domestic use." Thesis, Cape Technikon, 2000. http://hdl.handle.net/20.500.11838/884.

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Thesis (MTech(Chemical engineering))--Cape Technikon, Cape Town, 2000
The demand for pool heating has increased dramatically over the last few years. This is ascribed to the idea that a swimming pool is expensive and can only be used for four months of the year. Therefore, a need for a relatively inexpensive solar heating system, capable of heating pool water to comfortable temperatures for an extended period, does exist. The least expensive solar heating system for swimming pool heating on the market in South Africa is in the order of R 11000. This is a fixed system, usually mounted on the roof of a house. In order to ensure the safety of minors, a safety net or sail must be installed. This is an additional cost, which approximates R1500, yielding a total cost for safety and heating in the order of R 12500. Copper pipes packed in black material are utilised in these conventional heating systems, and it is the cost of this good heat conductor that makes these units expensive. In this study an alternative pool heating system constructed of PVC was investigated. The system is designed to be flexible, mobile, act as a safety mechanism and absorbs the maximum amount of solar energy available. Dark blue material as opposed to black PVC was selected for aesthetic reasons at the expense of maximum efficiency. The material strength was tested as well as the strength of adhesion. The influence of factors such as exposure to the sun and the effect of water containing chlorine and acid on the material were evaluated. Also, various means of channelling the water through the system for increased efficiency was investigated. A pilot model was constructed and its performance evaluated. It has been concluded that the alternative approach provides effective heating at a lower cost than current systems. Also, the durability of the design was found to be acceptable.
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Іщенко, Наталія Володимирівна, Наталия Владимировна Ищенко, and Nataliia Volodymyrivna Ishchenko. "Solar energy in sustainable future." Thesis, Вид-во СумДУ, 2007. http://essuir.sumdu.edu.ua/handle/123456789/17432.

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13

Sabaawi, Ahmed Mohammed Ahmed. "Nanoantennas for solar energy harvesting." Thesis, University of Newcastle upon Tyne, 2015. http://hdl.handle.net/10443/2921.

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Recent years have witnessed an enormous interest in developing solar cells by utilising different materials to increase their efficiency. This interest was motivated by the rapid world demand on cheap and clean energy sources, where the main source of world’s power is the fossil fuels. The current photovoltaics technology can not meet the solar power market due to the very low efficiency provided. The philosophy of this thesis is to find an efficient alternative by designing an efficient nanoantenna for receiving the solar radiation and coupling it to an integrated rectifier for AC to DC conversion. This thesis presents the design and optimisation of different types of nanoantennas with a performance comparison to find the optimum solution for this application. The figure of merit in choosing the best design was the captured electric field in the feed gap of the nanoantenna and the area under curve, which is essential in calculating the harvested energy. In addition, this thesis investigates the use of nanoarray instead of single elements. The aims is to increase the captured electric field at the gap of the array where all the elements will contribute in increasing the field in one common gap. Feeding lines will be employed to drive the captured fields from the centre of each single element towards the common gap. Another reason behind using nanoarrays is to reduce the number of rectifiers by using one rectifier per array instead of one rectifier per single element, and hence increase the total efficiency. Futhermore, a simple analysis on dipole nanoantenna using method of moments (MoM) is presented in this thesis. The results obtained from this method is compared with those found from finite element method (FEM) simulations and an acceptable agreement is achieved. To calculate the total conversion efficiency of solar rectennas, it is important to compute the rectification efficiency of the metal/insulator/metal (MIM) diode along with the coupling efficiency between the antenna and the diode. To this end, quantum mechanics was used to calculate the characteristics of the MIM diode. The results show that bowtie nanoantennas are the best candidate for this application in either the single and array form since they have wider bandwidth and larger area under curve. Additionally, the analysis using MoM gives the designer better understanding on how the system works and exhibits lower complexity and reduced computational requirements.
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Griffitts, Fletcher G. "Fullerenes in Solar Energy Cells." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/honors/394.

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This project involves controlling and characterizing the morphology of the active layer in a special type of organic photovoltaics (OPVs), consisting of porphyrin-fullerene composites, with emphasis on electron exchange interactions between the two components. The Vienna Ab Initio Simulation Package (VASP) is applied to model a variety of donor-acceptor complexes containing fullerene and porphyrin in terms of their stabilities as well as their geometric, electronic, and charge transfer features. The goal is to identify supramolecular chain structures with highest occupied molecular orbitals (HOMOs) and lowest unoccupied molecular orbitals (LUMOs) that may serve as electron (hole) transfer channels in a photovoltaic device. A stable structure, involving the planar adsorption of a porphyrin unit on a C60 hexagon, has been identified. The results for fullerene have been extended to phthalocyanine–fullerene dyads where the fullerene-derived unit Phenyl-C61-butyric acid methyl ester (PCBM) is connected to a porphyrin analogous electron donor through two oxygen-linked benzene rings. In both cases, the HOMO is located on the porphyrin segment, the LUMO on the fullerene component. As a fullerene, PCBM is a material of very high electron affinity, but it has better solubility properties than fullerene. It is often used in plastic solar cells or flexible electronics in conjunction with electron donor materials such as P3HT or other polymers. The results of our work contribute to the ongoing effort of using computational modeling to identify fullerene-based materials of potential relevance for organic photovoltaics.
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Ortíz, Elvis Richard Tello. "Sistemas fotovoltaicos e eólicos: metodologia para análise da complementaridade espacial-temporal com aplicação no dimensionamento e análise de risco financeiro." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-29122014-175607/.

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Este trabalho propõe caracterizar a complementaridade espacial-temporal entre energia eólica e solar fotovoltaica entre regiões do Brasil e estudar, no âmbito da comercialização de energia elétrica no Setor Elétrico Brasileiro - SEB, se um portfólio formado por estas fontes trazem vantagens econômicas relevantes para o investidor. Para atender a estes objetivos, foram estudados métodos para tratamento dos dados como a correção da irradiância solar, cálculo da energia gerada pelas fontes estudadas, o ambiente de contratação de energia elétrica no Brasil, métodos de otimização e modelos de análise de risco para contratação de energia no mercado livre de energia. A metodologia proposta para responder as questões colocadas foi aplicada em um estudo de caso envolvendo três regiões brasileiras em um horizonte de dez anos. Concluiu-se que existe a complementaridade energética entre as fontes nas diferentes regiões estudadas e em diferentes períodos de tempo. Confirmou-se que tecnicamente pode-se reduzir a oscilação na geração de energia analisando as fontes de forma complementar, porém, o custo de instalação da fonte fotovoltaica ainda é muito alto, inviabilizando até o momento investimentos em larga escala e de forma complementar a fonte eólica. Também verificou-se, dentro dos locais avaliados, que somente um dos três locais apresentou benefício econômico-financeiro com a formação de portfólio das fontes eólica e solar atuando no mercado de venda de energia e atendendo os critérios de risco limite estabelecidos quando avaliadas segundo a ótica da maximização da receita no mercado livre.
This thesis proposes to characterize the spatial-temporal complementarity between wind and solar photovoltaic energy between regions of Brazil and study, in the marketing of electricity in the Brazilian Electrical Sector - SEB, a portfolio formed by these sources bring significant economic benefits to the investor. To meet these goals, methods for data processing were studied as correction of solar irradiance calculation of the energy generated by the sources studied, the environment of contracting electricity in Brazil, optimization methods and models for risk analysis for contracting energy in the free energy market. The proposed methodology to answer the questions was applied in a case study involving three Brazilian regions with a horizon of ten years time series. It was concluded that there is complementarity between energy sources in the different regions studied and in different time periods. It was confirmed that technically can reduce the fluctuation in power generation by analyzing the complement of sources, however, the installation cost of photovoltaic power is still too high, preventing yet large-scale investments and complementary way the source wind. Also it was found within the sites evaluated, only one of the three sites presented economic and financial benefit by the portfolio of wind and solar sources acting in the sale of energy market and considering the risk criteria limit established when evaluated according to perspective of maximizing revenue in the free energy market.
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Santos, Romi Stella dos [UNESP]. "Conservação de energia: uma ferramenta para analisar o aproveitamento de energia solar em instalações residenciais." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/99283.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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No Brasil, devido ao forte crescimento da demanda de energia elétrica nas últimas décadas e com a necessidade de atender a esta procura, torna-se indispensável a inclusão no sistema elétrico brasileiro de programas de eficiência energética e a utilização de fontes alternativas de energia, pois com a construção de novas hidrelétricas e termoelétricas para atender o consumidor, ocorre inundações de grandes áreas e diminuição da emissão de gases para a atmosfera, o que causa fortes impactos ambientais. O uso de fontes alternativas também diminui a dependência do Brasil de combustíveis fósseis, pois futuramente ocorrerá o esgotamento de reservas naturais no país, tendo a necessidade de importar energia, o que elevará os preços das tarifas de energia elétrica. Para que haja a conservação de energia proveniente de fontes tradicionais e incentivar a implantação de energia solar no sistema elétrico brasileiro, desenvolveu-se um programa que analisa a viabilidade técnico-econômica de inclusão do sistema fotovoltaico e fototérmico ao sistema tradicional de distribuição de energia nas diversas regiões do Brasil em residências, pois é o setor que possui um maior potencial de economia de energia. O programa é uma ferramenta de fácil manuseio, de acesso rápido que permitem tomadas de decisões rápidas e seguras quanto à implantação de energia solar por parte do consumidor, além de fornecer em qual região é mais viável essa implantação.
In Brazil, due to a solid increasing in electrical energy demand at the last decades and due to the need to comply with this demand, became essential the inclusion of energetic efficiency programs and use of alternative energy resources in the Brazilian electrical supply system. However, the new hydro and thermo electrical power plants construction to attend the consumer cause strong environmental impacts, since they need big flooded lakes and eliminate theirs pollutants in the atmosphere, respectively. Moreover, the use of alternative energy resources decreases Brazil dependency of fossil fuels, besides it prevents the breakdown of the natural reserves and the need of energy importation, what would increase the charge for the electrical energy. To the energy conservation provided by traditional resources and to encourage the implementation of a solar energy based system in Brazil, it was developed a software that analyzes technical and economic feasibility of the photovoltaic and photothermical systems introduction in the traditional supply system on the several regions of Brazil to residential use, because this is a sector that has an elevated potential of energy saving. The software has a friendly interface, with quick access that allows the user to take quick and safe decisions, regarding to the solar energy implementation by consumers, and evaluate which area of the country is the most interesting to the implementation.
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17

Freitas, Flavio Santos 1982. "Eletrodos de materiais inorgânicos modificados para células solares híbridas." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248430.

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Orientador: Ana Flávia Nogueira
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: Este trabalho apresenta a síntese de moléculas carboxiladas e sua utilização como agentes compatibilizantes em sistemas híbridos inorgânico/orgânico. A caracterização e aplicação das interfaces destes sistemas híbridos de dióxido de titânio com poli(3-hexiltiofeno) (TiO2/P3HT) e silício monocristalino com poli(3-hexiltiofeno) (Si/P3HT) também foram estudadas. No primeiro sistema, TiO2/P3HT, a modificação superficial do TiO2 foi efetuada com três moléculas carboxiladas: ácido 2-tiofenocarboxílico (TCA), ácido 2-tiofenoacético (TAA) e ácido 2,4-tiofenodicarboxílico (TDA). Essas modificações demostraram que a molécula TAA apresenta melhor compatibilidade na interface, evidenciada por estudos fotofísicos de Espectroscopia de Absorção Transiente (TAS) e medidas de ângulo de contato. A célula solar com TAA (configuração invertida) apresentou eficiência de 0,03%, três vezes maior que a obtida no dispositivo padrão. Com a inserção do corante N719 na superfície do TiO2, a eficiência alcançou valores superiores a 1%. A eficiência dos dispositivos chegou a 1,35% com a inserção na camada de P3HT de nanopartículas de TiO2 na forma de bastão (TiO2 NB/TAA). Essa modificação da camada polimérica mostrou que o TiO2 NB/TAA apresentou propriedades ligeiramente superiores nos experimentos de fotoeletroquímica quando comparado com nanopartículas sintetizadas no formato esférico (TiO2 NE). Além disso, a técnica de Espalhamento de Raios-X a Baixo Ângulo (SAXS) mostrou que as nanopartículas TiO2 NB/TAA e TiO2 NE encontram-se distribuídas de forma homogênea pela matriz de P3HT. No segundo sistema, as células solares de Si/P3HT foram obtidas a partir de reações que modificaram a interface dos materiais. A adsorção química da molécula TAA sobre o óxido nativo (Si/SiOx/TAA) e a reação do grupo superficial Si-Cl com o reagente de Grignard brometo de tiofeno-magnésio (Si/Tiofeno) foram respectivamente caracterizadas por Espectroscopia de Infravermelho (FTIR) e Espectroscopia de Fotoelétrons por Raios-X (XPS). A contribuição do P3HT para o dispositivo foi avaliada a partir da comparação com uma junção Schottky (Al/Si/Au). Os valores de VOC obtidos nas células solares na presença de P3HT foram similares (~0,4 V) e superiores ao obtido no dispositivo sem o polímero (~0,2 V), evidenciando o domínio da junção Si/P3HT para as propriedades fotovoltaicas. O dispositivo Si/SiOx/TAA apresentou grande resistência em série, com eficiência de conversão de energia inferior a 0,5%. Porém, com a configuração Al/Si/Tiofeno/P3HT/Au, as células solares alcançaram valores de eficiência de 5,76%. A eficiência superior foi relacionada com a melhor adesão e compatibilidade entre o Si e o P3HT a partir de imagens de SEM
Abstract: This work presents the synthesis of carboxylated molecules and their use as compatibilizer agents in hybrid inorganic/organic systems. Characterization and application of the interfaces of those hybrid systems comprising titanium dioxide with poly(3-hexylthiophene) (TiO2/P3HT) and monocrystalline silicon with poly(3-hexylthiophene) (Si/P3HT) will also be described. In the former system, TiO2/P3HT, the TiO2 surface was modified with three molecules: 2-thiophenecarboxylic acid (TCA), 2-thiopheneacetic acid (TAA) and 2,4- thiophenedicarboxylic acid (TDA). Transient Absorption Spectroscopy (TAS) photophysical studies and contact angle measurements demonstrated that TAA presents the best compatibility in the interface. Solar cells modified with TAA, set up in inverted configuration, showed 0.03% of overall energy conversion efficiency, which is three times larger than the one obtained from a standard device. Replacing TAA by N719 dye on TiO2 surface increased the efficiency, achieving values higher than 1%. Inserting TiO2 rod-shaped nanoparticles (TiO2 NB/TAA) on P3HT layer of the latter system resulted in 1.35% overall efficiency. Photoelectrochemical experiments demonstrated that this modification using TiO2 NB/TAA increases exciton separation rate and conductivity properties slightly enhanced compared to spherical nanoparticles (TiO2 NE/TAA). Small-Angle X-ray Scattering (SAXS) showed that TiO2 NB/TAA and TiO2 NE nanoparticles are homogeneously distributed in the P3HT matrix. In the Si/P3HT hybrid system, the inorganic/organic interface was modified through chemical adsorption of TAA molecules on the native oxide (Si/SiOx/TAA) and a reaction of the surface Si-Cl groups with Grignard reagent 2-thiophene-magnesium bromide (Si/Tiofeno). Both reactions were characterized using Infrared Spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS). The contribution of P3HT to the p-n junction formation in the photovoltaic device was evaluated from a comparison with a Schottky junction (Al/Si/Au). The VOC values obtained with P3HT were similar among the experiments (around 0.4 V) and higher than without the polymer (around 0.2 V). This observation highlights the dominance of Si/P3HT for photovoltaic properties. The Si/SiOx/TAA device exhibited a high series resistance, with energy conversion efficiency lower than 0.5%. However, using Al/Si/Tiofeno/P3HT/Au configuration, the solar cells reached 5.76% efficiency. The higher values might be related to a better adhesion and compatibility between Si and P3HT, which was observed from SEM images
Doutorado
Quimica Inorganica
Doutor em Ciências
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18

Sholin, Veronica. "Luminescent solar concentrators and all-inorganic nanoparticle solar cells for solar energy harvesting /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2008. http://uclibs.org/PID/11984.

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19

Mahoney, Luther. "Solar hydrogen and solar electricity using mesoporous materials." Thesis, University of South Dakota, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3723927.

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The development of cost-effective materials for effective utilization of solar energy is a major challenge for solving the energy problems that face the world. This thesis work relates to the development of mesoporous materials for solar energy applications in the areas of photocatalytic water splitting and the generation of electricity. Mesoporous materials were employed throughout the studies because of their favorable physico-chemical properties such as high surface areas and large porosities. The first project was related to the use of a cubic periodic mesoporous material, MCM-48. The studies showed that chromium loading directly affected the phase of mesoporous silica formed. Furthermore, within the cubic MCM-48 structure, the loading of polychromate species determined the concentration of solar hydrogen produced. In an effort to determine the potential of mesoporous materials, titanium dioxide was prepared using the Evaporation-Induced Self-Assembly (EISA) synthetic method. The aging period directly determined the amount of various phases of titanium dioxide. This method was extended for the preparation of cobalt doped titanium dioxide for solar simulated hydrogen evolution. In another study, metal doped systems were synthesized using the EISA procedure and rhodamine B (RhB) dye sensitized and metal doped titania mesoporous materials were evaluated for visible light hydrogen evolution. The final study employed various mesoporous titanium dioxide materials for N719 dye sensitized solar cell (DSSC) materials for photovoltaic applications. The materials were extensively characterized using powder X-ray diffraction (XRD), nitrogen physisorption, diffuse reflectance spectroscopy (DRS), UV-Vis spectroscopy, Fourier-Transform-Infrared Spectroscopy (FT-IR), Raman spectroscopy, chemisorption, photoluminescence (PL), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). In addition, photoelectrochemical measurements were completed using current-voltage (I-V) curves, external quantum efficiency (EQE) curves, electrochemical impedance spectroscopy (EIS), and transient spectroscopy. The thesis work presented provides a better understanding of the role of mesoporous materials for solar hydrogen and solar electricity production.

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Mattos, Sérgio Ricardo de. "Análise do rendimento térmico do aquecedor solar parabólico cilíndrico /." Guaratinguetá : [s.n.], 2011. http://hdl.handle.net/11449/99302.

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Orientador: Teófilo Miguel de Souza
Banca: Osiris Canciglieri Junior
Banca: Rubens Alves Dias
Resumo: Este aquecedor solar foi construído em uma estrutura metálica, que tem um revestimento de polietileno reflexivo parabólico cilíndrico, onde no foco da parábola passa uma serpentina com sete tubos em cobre de 9,5 mm e o projeto foi desenvolvido para obter temperaturas mais elevadas do que os aquecedores planos. O objetivo desta dissertação foi atingir temperaturas mais altas na fase líquida. As temperaturas alcançadas foram obtidas utilizando uma densidade de potência solar que variou entre (1.000±10) W/m2, nas vazões de: 66, 54, 42, 30, 27, 24, 21, 18, 15, 12 e 9 litros por hora. A máxima temperatura atingida utilizando-se a vazão de nove litros por hora foi de 71°C, permitindo uma diferença de temperatura, em relação a temperatura ambiente de 43°C. A máxima vazão utilizada no aquecedor solar parabólico cilíndrico foi de 66 litros por hora e obteve-se uma temperatura de 38°C, sendo a diferença em relação à temperatura ambiente de 6°C. Assim com o desenvolvimento do aquecedor solar parabólico cilíndrico obtiveram-se temperaturas maiores em uma área de captação menor, do que em aquecedor convencionais planos e com rendimentos superiores a 70% em sua maior faixa de operação
Abstract: This solar heater is constructed of a metallic structure, which has a polyethylene coating reflective parabolic cylindrical, where the focus of the parable is a serpentine seven copper pipes of 9.5 mm and the project was designed to obtain higher temperatures than the heaters plans and the objective of this thesis was to reach higher temperatures in the liquid phase. The temperatures reached were obtained using a solar power density ranged from (1000±10) W/m2, the flow rates: 66, 54, 42, 30, 27, 24, 21, 18, 15, 12 and 9 liters per hour. The maximum temperature reached by using the flow of nine liters per hour was 71°C, allowing a temperature difference in relation to ambient temperature of 43°C. The maximum flow rate used in the cylindrical parabolic solar heater was 66 liters per hour and obtained a temperature of 38°C, and the difference in the ambient temperature of 6°C. So with the development of a cylindrical parabolic solar heater temperatures were obtained in a larger area smaller than in conventional heating plans and with performance up to 70% on the higher range of operation
Mestre
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21

Wigginton, James Michael. "Optical analysis of cavity solar energy receivers." Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/17348.

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22

Canto, Mario Afonso Ribeiro do [UNESP]. "Projeto e desenvolvimento de um sistema automatizado para monitoramento de fontes alternativas de energia." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/99291.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A utilização de fontes alternativas e renováveis de energia apresenta-se como um recurso energético com um mínimo de impacto ambiental. Com o crescimento do uso destes recursos, torna-se importante o conhecimento dos mesmos do comportamento em relação às condições ambientais naturais. As alterações das condições climáticas, por vezes, causam incertezas quanto ao rendimento dos sistemas alternativos e renováveis de geração de energia. Este trabalho apresenta-se como uma forma de conhecimento do comportamento das fontes de energia perante diversas condições do clima. Esta dissertação tem por objetivo contribuir com o conhecimento sobre o comportamento de fontes alternativas de energia comerciais e desenvolvidas no Centro de Energias Renováveis da UNESP de Guaratinguetá. Neste trabalho, foi desenvolvido um sistema de aquisição e tratamento de dados para monitorar o comportamento de fontes alternativas e renováveis de energia e das condições ambientais. Nesse sistema são especificados sensores para monitoramento das condições ambientais e para monitoramento dos dispositivos componentes das fontes de energia alternativa. O desenvolvimento de um software para coleta de dados e controle dos dispositivos de medição é parte integrante do trabalho para viabilizar o acesso às informações de forma a facilitar a análise de resultados. O protótipo construído durante o desenvolvimento da dissertação possibilitou o monitoramento das fontes de energia do laboratório como também das condições atmosféricas locais.
The renewable and alternative energy sources utilization presents-itself as an energy resource with a minimum environmental impact. With the growth of the use of these resources, becomes so important the knowledge of the performace regarding to the natural environmental conditions. The climatic conditions alterations, for times, cause users doubts of confidance of the renewable and alternative systems performance in energy generation. This work presents-itself as a form of knowledge of the performance of the energy sources to diversiity climate conditions. This dissertation has for objective contribute with the knowledge about the performance of commercial and alternative energy sources and developed in the Renewable Energies Center of the UNESP, Guaratinguetá. Was developed a system of data acquisition and analysis for monitoring renewable and alternative energy sources and environmental conditions. In this work, are determined and specified sensors for monitoring of the environmental conditions and for monitoring of the devices components of the alternative energy.sources The development of a data aquisition software and control of measurement is a part to make easy the access the information to facilitate the results analysis. The prototype built during the dissertation development enabled the energy sources monitoring of the center as also of the local atmospheric conditions.
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23

Beck, Madeleine, and Johannes Verweyen. "Utilization of Solar Energy in Liljeholmskajen." Thesis, KTH, Energiteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-99036.

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For the sustainable development of society it is crucial to find a way to decrease dependency on fossil fuels. Buildings today are big energy-consumers making this sector an important one to examine and develop further. This thesis investigates the possibility of using solar energy in Liljeholmskajen, a district in Stockholm, by considering technical, economic and environment aspects of its implementation.This report analyses different technologies for solar energy, with its focus on thermal collectors, thin film panels and monocrystalline cells. The analysis covers factors such as the efficiency, longevity, and specific constraints for the system. Further the area of Liljeholmskajen is studied, with a focus on the energy requirements. The analysis is based on three different buildings, which are chosen to be representative for the district. Based on this analysis, the total energy demand that could be met by each type of solar energy can be assessed, and their respective costs of implementation calculated.Based on these results conclusions are drawn, including how solar energy could be used in the area in the most effective way. This report suggests that the best solution today would be a combination of solar thermal collectors and thin film panels, although this also depends on the size of the possible investment.Furthermore for the future, if the existing rock-caverns in the area were converted into heat storage facilities, the heat storage wouldn’t be a limiting factor for thermal collectors anymore, and an increased usage of thermal collectors would therefore be recommended.
För att uppnå en hållbar samhällsutveckling är det i dagsläget mycket viktigt att försöka hitta en lösning på hur man ska minska beroendet av fossila bränslen. En av de stora energiförbrukarna i dagens samhälle är alla byggnader, vilket gör denna sektor till ett viktigt föremål för vidareutveckling. Denna rapport undersöker möjligheterna för en eventuell användning av solenergi i Liljeholmskajen, en stadsdel i södra Stockholm, genom att ta i beaktning både teknik, ekonomi och miljöaspekter.Rapporten analyserar olika teknologier för användning av solenergi, med tyngdpunkten på termiska solfångare samt tunnfilms- och monokristallina solceller. Analysen omfattar områden såsom verkningsgrad, livslängd och systemspecifika begränsningar. Vidare studeras även Liljeholmskajen och dess energibehov. Analysen baseras på tre olika byggnader som kan anses vara representativa för stadsdelen. Detta leder sedan till att det totala energibehovet i Liljeholmskajen som kan täckas med hjälp av respektive teknik, samt deras investeringskostnader kan beräknas.Utifrån de erhållna resultaten har en slutsats dragits, vilken påvisar hur man på bästa sätt skulle kunna använda sig av solenergi i Liljeholmskajen. I dagsläget vore en kombination av solfångare och tunnfilms celler att rekommendera, men det är även beroende av hur stor investering man kan göra.Om man i framtiden skulle omvandla bergrummen som finns i området till värmelager så skulle inte längre lagringsmöjligheterna vara en begränsande faktor för solfångarsystem. Detta skulle innebära att en ökad användning av solfångare vore att rekommendera.
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24

Giddings, S. L. "Heterogeneous reactions in solar energy conversion." Thesis, Swansea University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637056.

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Photochemical systems for the splitting of water into hydrogen and oxygen represent an attractive route for the conversion of solar energy into a chemical fuel. However, the success of such systems depends on the identification of suitable redox catalysts for the oxidation and reduction processes. While colloidal platinum has proved to be an efficient catalyst for the reduction of water, the development of stable and effective catalysts for water oxidation has been less successful. The work described in this thesis involves the study of ruthenium dioxide hydrate (RuO2.xH2)O as a heterogeneous catalyst for the oxidation of water to oxygen. Although this material has already been widely used as an oxygen catalyst, there have been many doubts as to its ability to act in this capacity. In Chapter Three an attempt is made to resolve this controversy via an investigation of the stability and catalytic activity of RuO2.xH2O when exposed to various oxidising agents. The results indicate that the catalytic activity and corrosion stability of an RuO2.xH2O sample is related to its degree of hydration. In Chapter Four an investigation is described into the effect of heat-treatment of RuO2.xH2O at different temperatures on its physical and chemical properties. From these results it appears that any sample of RuO2xH2O may be transformed into a stable, reproducible oxygen catalyst by simply heat-treating it at 140-150oC in air for ca. 5 hours. The latter conditions represent an optimum for catalytic activity where anodic corrosion is absent. This 'thermally-activated' RuO2.xH2O is shown to compare favourably with alternative oxygen catalysts. Chapters Five and Six involve a kinetic study of the RuO2.xH2O-catalysed oxidation of water by Ce(IV) ions in an attempt to elucidate the mechanism of catalysis of the oxide powder. The study is based on an electrochemical model in which the RuO2.xH2O particles are considered as microelectrodes. The initial charging of the RuO2.xH2O prior to water oxidation is discussed in Chapter Five and in Chapter Six the effect of an increase in the redox potential of the Ce4+/Ce3+ couple by changing the acid medium is investigated.
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25

Bengtsson, Tobias, and Håkan Hult. "Combining Solar Energy and UPS Systems." Thesis, KTH, Tillämpad termodynamik och kylteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-148042.

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Solar Power and Uninterruptible Power Supply (UPS) are two technologies that are growing rapidly. The demand for solar energy is mainly driven by the trend towards cheaper solar cells, making it economically profitable for a larger range of applications. However, solar power has yet to reach grid parity in many geographical areas, which makes ways to reduce the cost of solar power systems important. This thesis investigates the possibility and potential economic synergies of combining solar power with UPS systems, which have been previously researched only from a purely technical point of view. This thesis instead evaluates the hypothesis that a combined solar and UPS system might save additional costs compared to regular grid-tied systems, even in a stable power grid. The primary reason is that on-line UPS systems rectifies and inverts all electricity, which means that solar energy can be delivered to the DC part of the UPS system instead of an AC grid, avoiding the installation of additional inverters in the solar power system. The study is divided into three parts. The first part is a computer simulation using MATLAB, which has an explorative method and aims to simulate a combined system before experimenting physically with it. The second part consists of experiments on a physical prototype system based on basic UPS and solar power components. The third part is an economical assessment of investment costs and energy balances, comparing two separate systems (UPS and solar power separate) to one combined (UPS & solar power). The results from the prototype system show that adding solar power to an UPS system does not interfere with the UPS functionality in any major way, however for optimal performance some additional integration may be necessary. On the contrary, the additional power terminal that the solar panels constitute, can increase system performance during certain operational conditions. The result of the economic analysis shows that a combined system has potential for both a lower investment cost due to cheaper components and increased energy savings through lower conversion losses. The conclusion from the study is that a combined solar energy and UPS system is technically feasible. Furthermore, a combined system has clear economic advantages over two separate systems. This means that a combined system might be economically profitable even in situations where a separate system is not.
Solenergi och avbrottsfri kraftförsörjning (UPS) är två tekniker som växer snabbt. Efterfrågan på solenergi ökar huvudsakligen på grund av den snabba utvecklingen mot billigare solceller, vilket lett till att solenergi blivit lönsamt i en större mängd applikationer. I många områden är solenergi dock fortfarande inte kostnadsmässigt konkurrenskraftigt jämfört med traditionella energikällor, vilket gör en fortsatt sänkning av kostnaderna för solenergi till en viktig fråga för solenergiindustrin. Detta examensarbete har som syfte att undersöka om det är tekniskt möjligt att kombinera solenergi med UPS-system samt potentialen för ekonomiska synergier med denna kombination. Tidigare forskning inom området har endast undersökt denna kombination från en rent teknisk synvinkel. Detta examensarbete driver istället hypotesen att ett kombinerat solenergi- och UPS-system kan leda till större kostnadsbesparingar jämfört med ett traditionellt nätanslutet solenergisystem, även i ett stabilt elnät som i Sverige. En on-line UPS skyddar en känslig last genom att kontinuerligt likrikta och sedan åter växelrikta inkommande ström för att därmed både isolera lasten från nätet samt höja strömkvalitén. I UPS-systemet finns därmed en likströmsdel dit solpanelerna direkt kan kopplas istället för att skicka den genererade solenergin ut på elnätet. Därmed undviks inköp och installation av sol-växelriktare i solenergisystemet. Studien är uppdelad i tre delar. Första delen är en datorsimulering i MATLAB och syftar till att explorativt undersöka det kombinerade systemet för en optimerad design innan fysiska experiment utförs. Den andra delen av studien utgörs av experiment på ett fysiskt prototypsystem baserat på ett principiellt UPS- och solenergisystem. Den tredje delen av studien är en ekonomisk analys av både investeringskostnader och energibalanser som jämför ett kombinerat system (UPS & sol) med två separata system (UPS & sol separat). Resultaten från prototypsystemet visar att påkopplandet av solceller i en principiell UPS har mycket låg påverkan på UPS-systemets funktionalitet, samt att solcellerna som en extra energikälla under vissa driftförhållanden kan ha en positiv påverkan på UPS-systemet. För optimal prestanda kan dock en viss integration av systemen krävas.  Resultatet från den ekonomiska analysen visar att ett kombinerat system har potential att sänka investeringskostnaden genom billigare komponenter. Ett kombinerat system kan även leda till en högre energibesparing jämfört med ett nätanslutet solenergisystem eftersom konverteringsförlusterna i UPS-systemet sjunker i det kombinerade systemet. Slutsatsen av studierna är att ett kombinerat solenergi- och UPS-system är tekniskt möjligt. Dessutom finns betydande ekonomiska synergier med ett kombinerat system. Detta innebär att ett kombinerat system kan vara lönsamt även i fall där ett separat solelsystem inte är det.
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26

Hassan, Ibrahim. "Solar energy conversion by photoelectrochemical processes." Thesis, University of Bath, 2011. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542078.

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27

Liang, Xusheng, Elvis Tanyi, and Xin Zou. "Charging electric cars from solar energy." Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-11919.

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Before vehicles were heavily relied on coal, fossil fuels and wind for power.  Now, they are rapidly being replaced by electric vehicles and or plug-in hybrid electric cars. But these electric cars are still faced with the problem of energy availability because they rely on energy from biomass, hydro power and wind turbines for power generation. The abundance of solar radiation and its use as solar energy as a power source in driving these rapidly increasing electric cars is not only an important decision but also a necessary condition for eradication of environmental pollution. This study presents a model for charging electric cars from solar energy. Little focus on detailed technologies involved from solar energy capture to battery charging but our main focus is how to provide a modified charging parking lot in Karlskrona city-Sweden. With a surface area of 2850m2, we were able to choose 1STH-350-WH as the right PV modules. Based on the latitude of our design area, a computed 71 degrees angle positioning between solar panel and roof so as to maximise the surface area and optimise the solar irradiance gathering. Based on the power output of approximately116kW these PV modules generated, we further analysed and selected SDP 30KW inverter and Monocrystalline Silicon (1SolTech 1STH-350-WH (350W) solar modules. Also we provide different car charging method by choosing the SAE J1772 standard as one of specifications for dedicated vehicle charging and Clipper Creek HSC-40 as our option of charger. With the data of the generating solar energy every day, charging time, consuming power, we can estimate how many cars the system can handle to charge. Moreover, our system provides AC power from AC power network by general socket type F. We finally concluded that, our model for charging of electric car batteries was not only supportive but efficient in terms of extracting solar energy from sunlight to charge electric cars, thus making the region an eco-friendly place.
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28

Ferrer, Martínez Claudia. "Machine Learning for Solar Energy Prediction." Thesis, Högskolan i Gävle, Avdelningen för elektronik, matematik och naturvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-27423.

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This thesis consists of the study of different Machine Learning models used to predict solar power data in photovoltaic plants. The process of implement a model of Machine Learning will be reviewed step by step: to collect the data, to pre-process the data in order to make it able to use as input for the model, to divide the data into training data and testing data, to train the Machine Learning algorithm with the training data, to evaluate the algorithm with the testing data, and to make the necessary changes to achieve the best results. The thesis will start with a brief introduction to solar energy in one part, and an introduction to Machine Learning in another part. The theory of different models and algorithms of supervised learning will be reviewed, such as Decision Trees, Naïve Bayer Classification, Support Vector Machines (SVM), K-Nearest Neighbor (KNN), Linear Regression, Logistic Regression, Artificial Neural Network (ANN). Then, the methods Linear Regression, SVM Regression and Artificial Neural Network will be implemented using MATLAB in order to predict solar energy from historical data of photovoltaic plants. The data used to train and test the models is extracted from the National Renewable Energy Laboratory (NREL), that provides a dataset called “Solar Power Data for Integration Studies” intended for use by Project developers and university researchers. The dataset consist of 1 year of hourly power data for approximately 6000 simulated PV plants throughout the United States. Finally, once the different models have been implemented, the results show that the technique which provide the best results is Linear Regression.
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29

Bokfors, Sofie. "Awareness on Solar Energy in Kenya." Thesis, KTH, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-245193.

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Solar energy coupled with energy efficiency awareness can be an important step to achieving the final goal of having a sustainable environment in the country. Together with a good energy policy including regulations, this goal can be achieved as it will help consumers make more rational decisions when it comes to new technology. A key problem identified in this work is the lack of awareness and strict energy policies. The current funds put in place are not mobile and have not got to a large number of people. The government’s regulations on the other hand are not strict. This report aims to improve the current status by suggesting strategies to reach out to as many people as possible and educate them about solar energy options in Kenya. It aims to prepare to build a platform that creates awareness on solar energy, energy efficiency as well as the policies and finances needed to support their uptake. In order to build this platform, analysis has been done through research and meetings with stakeholders who have provided first-hand information in order to formulate the foundation to a future platform. The information gathered has then been used to explain and meet the challenges faced in solar energy in Kenya. The conclusion of this project was that majority of the people in Kenya lack required knowledge about solar energy. There is need to create awareness in solar energy.
Solenergi i kombination med medvetenhet gällande  energieffektivitet är ett viktigt steg för att uppnå det slutliga målet, som är att ha en hållbar utveckling gällande energi och miljö i Kenya. Tillsammans med en bra energipolitik som har tydliga regler, kan detta mål uppnås. Detta kommer att hjälpa konsumenterna att fatta mer rationella beslut när det gäller ny teknik. Ett nyckelproblem som identifieras i detta arbete är bristen på medvetenhet och även bristen av en strikt energipolitik. Kunskapen om solenergi och energieffektivitet har inte nått ut till majoriteten av människorna i Kenya. I dagsläget är lagarna gällande energi inte tillräckligt strikta. Denna rapport syftar till att förbättra den nuvarande situationen genom att föreslå strategier för att nå ut till maximalt antal invånare och utbilda dem om solenergialternativ. Rapporten syftar till att lägga en grund för att kunna bygga upp en plattform som skapar medvetenhet om solenergi och energieffektivitet, och vad som krävs politiskt och finansiellt för att stödja detta. För att kunna bygga upp denna plattform har analyser gjorts genom litteraturstudier och möten med intressenter som har bidragit med förstahandsinformation, detta för att kunna skapa grunden till den framtida plattformen. Informationen som samlats in har sedan använts för att förklara och för att försöka möta utmaningarna gällande solenergi i Kenya. Slutsatsen av detta projekt är att majoriteten invånarna i landet saknar nödvändig kunskap om solenergi. Det är därför viktigt att skapa medvetenhet gällande solenergi.
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30

Bokfors, Sofie. "Awareness on Solar Energy in Kenya." Thesis, KTH, Energiteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-250019.

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Solar energy coupled with energy efficiency awareness can be an important step to achieving thefinal goal of having a sustainable environment in the country. Together with a good energy policyincluding regulations, this goal can be achieved as it will help consumers make more rationaldecisions when it comes to new technology. A key problem identified in this work is the lack ofawareness and strict energy policies. The current funds put in place are not mobile and have not got to a large number of people. Thegovernment’s regulations on the other hand are not strict. This report aims to improve the currentstatus by suggesting strategies to reach out to as many people as possible and educate them aboutsolar energy options in Kenya. It aims to prepare to build a platform that creates awareness onsolar energy, energy efficiency as well as the policies and finances needed to support their uptake. In order to build this platform, analysis has been done through research and meetings withstakeholders who have provided first-hand information in order to formulate the foundation to afuture platform. The information gathered has then been used to explain and meet the challengesfaced in solar energy in Kenya. The conclusion of this project was that majority of the people inKenya lack required knowledge about solar energy. There is need to create awareness in solarenergy.
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31

Borg, Isak, August Dixelius, and David Östlund. "Interactive Visualization of Solar Energy Data." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385793.

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Sweden has one of the lowest solar energy productions in Europe even though the weather conditions are comparable to Europe’s largest solar energy producer. Although the majority of the Swedish population is in favour of spending more money on services that can limit climate change, the growth of installed solar cells is slower than that of other countries with similar climate in Europe. To inspire people to install solar panels we created an interactive map with information regarding the solar parks in Uppland, a county in Sweden. Our goal was that this system would help spread awareness of the fact that solar parks work efficiently in Sweden. The program was then installed on a tablet which was put in a public space together with an LED installation to reach as broad of an audience as possible. To draw the passer by’s attention, the LED installation was connected to the map which shows the energy production of the selected solar park in a colour scale.
Sverige har en av de lägsta produktionen av solenergi i Europa trots att deras väderförhållanden är jämförbara med Europas största producenter av solenergi. Även fast majoriteten av Sveriges befolkning är villiga att spendera mer pengar på tjänster som kan begränsa klimatförändringar är tillväxten av nya solpaneler långsammare än i andra Europeiska länder med liknande klimat. För att inspirera personer att installara solpaneler har vi skapat en interaktiv karta med information gällande solparker i Uppland. Vårt mål är att programmet skulle öka medvetenheten om solparkers effektivitet i Sverige. Programmet blev sedan installerat på en surfplatta som monterades på en offentlig plats tillsammans med en LED-installation för att nå en så omfattande publik som möjligt. För att dra till sig förbipasserandes uppmärksamhet så kopplades LED-installationen till kartan som visar energiproduktionen hos den valda solparken i en färgskala.
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32

SCILLETTA, CLAUDIA. "Carbon nanotubes for solar energy conversion." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2009. http://hdl.handle.net/2108/1039.

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E’ stato dimostrato che la nanotecnologia ed i nanomateriali possono offrire valide soluzioni per migliorare l’efficienza di conversione sfruttando gli effetti indotti a scala mesoscopica. In questo ambito di ricerche, l’attività sui nano tubi di carbonio CNT come elementi costituenti di dispositivi di conversione dell’energia solare è in grande sviluppo. Il lavoro presentato in questa tesi è stato dedicato all’investigazione dei meccanismi fisici alla base della foto-risposta dei nanotubi di carbonio a multi parete (MWCNT) quando vengono utilizzati in celle elettrochimiche e in dispositivi a stato solido. Larga parte dell’attività è consistita nello sviluppo di strategie per la crescita controllata dei MWCNT. MWCNTs sono stati sintetizzati mediante CVD termico variando i parametri di crescita sperimentali. Utilizzando tecniche di caratterizzazione morfologica e strutturale, è stato possibile fissare i parametri di sintesi appropriati per ottenere strutture di MWCNT controllate su specifici substrati. Esperimenti di generazione di corrente fotochimica da parte dei MWCNT cresciuti su substrati SiO2/Si sono stati effettuati così come misure di fotoconduttività a stato solido. Tali esperimenti hanno confermato la capacità dei MWCNT di generare una corrente elettronica sotto illuminazione, nonostante la loro stretta similarità con la grafite metallica. Spettri EELS mostrano una spalla ad energie comprese tra 2 - 4 eV, sotto il tipico plasmone π -π* della grafite altamente orientata. Questa può essere associata, in analogia con i nano tubi a singola parete SWNT, alla presenza di singolarità di Van Hove nella densità degli stati elettronici. Tali transizioni permettono la generazione sotto illuminazione di un eccitone. L’elettrolita all’interno della cella chimica e/o la presenza di giunzioni Schottky tra MWCNT differenti separano le cariche. I risultati di fotoconducibilità a stato solido sono stati confrontati con quelli ottenuti negli esperimenti fotochimici, e quelli riportati in letteratura. Sulla base di calcoli teorici della DOS di nanotubi multi pareti (4WCNT), è possibile affermare che i MWCNT possono creare delle giunzioni locali p-n e/o Schottky con il substrato di silicio, dando luogo ad una estesa regione di svuotamento. Questo implica una modifica delle caratteristiche degli spettri di foto corrente attesi per i MWCNT. MWCNT sono stati decorati con nanoparticelle di rame e la loro foto risposta è stata studiata e confrontata con quella dei soli nano tubi. L’efficienza quantica dei sistemi ibridi aumenta su tutto lo spettro e due modelli sono proposti per spiegare questo risultato. Infine una prima misura sulle prestazioni di un dispositivo MWCNTs/SiO2/Si come cella fotovoltaica è stata effettuata mediante un simulatore solare. La caratteristica I-V sotto illuminazione non è la ben nota curva aspettata per le celle PV, ma mostra come dispositivi a stato solido basati sui MWCNT possano operare come generatore di potenza attivo sotto illuminazione solare.
It has been demonstrated that nanotechnology and nanomaterials could offer valid solutions to improve the conversion efficiency by exploiting effects induced at mesoscopic scales. In this research field, the activity on carbon nanotubes CNTs as building blocks for solar energy conversion devices is developing. The work presented in this thesis has been devoted to investigate the physical mechanisms underlying the photoresponse generation of multiwall carbon nanotubes (MWCNTs) when exploited in electrochemical cells and solid-state devices. A large part of the activity has consisted of the development of suitable strategies for the controlled growth of MWCNTs. MWCNTs have been synthesised by thermal CVD varying the experimental growth parameters. By using morphological and structural characterization techniques, it has been possible to fix the proper synthesis parameters to obtain controlled MWCNTs structures on specific substrates. Experiments of photochemical current generation by MWCNTs grown on SiO2/Si substrates have been performed as well as solid-state photoconductivity measurements. They have confirmed the capability of MWCNTs to generate a current of electrons under light irradiation, despite their close similarity to metallic graphite. EELS spectra show a shoulder at energies 2-4 eV, below the typical plasmon π -π* peak for HOPG. That can be associated, similarly to SWCNTs, to the presence of van Hove singularities in electronic density of states. These transitions allow the generation upon illumination of an exciton. The electrolyte inside the chemical cell and/or the presence of localized Schottky junctions between different MWCNTs separates the charges. The solid-state photoconductivity results have been compared with those obtained in photochemical experiments, and with other described in literature. On the basis of theoretical calculations of DOS for a specific four-wall carbon nanotube (4WCNT), it is possible to affirm that MWCNTs are able to locally create p-n and/or Schottky junctions with the silicon substrate underneath, giving rise to an extended depletion layer. This implies a modification of the feature in the expected photocurrent spectrum of MWCNTs. MWCNTs have been decorated by Cu nanoparticles and their photoresponse has been studied and compared with that of bare nanotubes. The quantum efficiency of the hybrid system increases over the entire spectrum and two models have been proposed to explain these results. Finally, a first measurement of the performance of a MWCNTs/SiO2/Si device as PV cell has been performed by using a solar simulator. The I-V characteristic under illumination is not the expected well-shaped curve of a PV cell, but it demonstrates that the MWCNT solid-state device can operate as an active power supply element under solar illumination.
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33

Reusswig, Philip David. "Sensitized energy transfer for organic solar cells, optical solar concentrators, and solar pumped lasers." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/93831.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 123-130).
The separation of chromophore absorption and excitonic processes, such as singlet exciton fission and photoluminescence, offers several advantages to the design of organic solar cells and luminescent solar concentrators (LSCs) for the end goal of achieving a lower cost solar energy generation. This thesis explores three new device architectures to overcome limited solar absorption in singlet-exciton-fission based solar cells and neodymium based LSCs. The process of singlet exciton fission is de-coupled from photon absorption, exciton diffusion, and charge transport in singlet-exciton-fission based solar cells by inserting a singlet fission material at the donor-acceptor interface of an organic solar cell. Singlet excitons generated in the singlet exciton donor are transferred to the singlet fission material through near field energy transfer. In this device structure, the singlet donor can be chosen for high photon absorption, exciton diffusion, and charge transport, and the singlet fission sensitizer can be selected for high singlet fission efficiency. We demonstrated a doubling of the external quantum efficiency from 12.8% to 27.6% in a singlet donor (TPTPA) through the introduction of thin film singlet fission sensitizer (rubrene) for high efficiency organic solar cells. To reduce the cost of electricity generated by sunlight via LSC systems, replacing the expensive high efficiency visible photovoltaic (PV) elements with cheap, high efficiency, earth abundant near-infrared PV elements made with silicon. This requires replacing within the LSC the visible emitting chromophores with near infrared emitters. Here, we present the use of a lanthanide ion, neodymium--colloidal nanocrystal energy cascade system as a promising LSC emitter scheme for the silicon spectral region. Peak optical quantum efficiencies of 43% in a Nd³+:glass based LSC are demonstrated with simulated high geometric gain performance. With cascade energy transfer, the optical quantum efficiency in the visible of a Nd³+:glass is significantly improved with peak efficiency of 28%. The enhanced solar absorption of Nd³+:glass through cascade energy transfer can be extended into the infrared with more optimal sensitizers. The idea of directly converting broad-band solar radiation into coherent and narrow-band laser radiation could enable many attractive technologies for solar energy. Here, we present an architecture for solar pumped lasers that uses a luminescent solar concentrator to decouple the conventional trade-off between solar absorption efficiency and the mode volume of the optical gain material. We report a 750-[mu]m-thick Nd³+-doped YAG planar waveguide sensitized by a luminescent CdSe/CdZnS (core/shell) colloidal nanocrystal, yielding a peak cascade energy transfer of 14%, a broad spectral response in the visible portion of the solar spectrum, and an equivalent quasi-CW solar lasing threshold of 20 W-cm2 , or approximately 200 suns. The efficient coupling of incoherent, spectrally broad sunlight in small gain volumes should allow the generation of coherent laser light from intensities of less than 100 suns.
by Philip David Reusswig.
Ph. D.
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34

Santos, Romi Stella dos. "Conservação de energia: uma ferramenta para analisar o aproveitamento de energia solar em instalações residenciais /." Guaratinguetá : [s.n.], 2008. http://hdl.handle.net/11449/99283.

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Orientador: Oscar Armando Maldonado Astorga
Banca: Durval Luiz Silva Ricciulli
Banca: George Alves Soares
Resumo: No Brasil, devido ao forte crescimento da demanda de energia elétrica nas últimas décadas e com a necessidade de atender a esta procura, torna-se indispensável a inclusão no sistema elétrico brasileiro de programas de eficiência energética e a utilização de fontes alternativas de energia, pois com a construção de novas hidrelétricas e termoelétricas para atender o consumidor, ocorre inundações de grandes áreas e diminuição da emissão de gases para a atmosfera, o que causa fortes impactos ambientais. O uso de fontes alternativas também diminui a dependência do Brasil de combustíveis fósseis, pois futuramente ocorrerá o esgotamento de reservas naturais no país, tendo a necessidade de importar energia, o que elevará os preços das tarifas de energia elétrica. Para que haja a conservação de energia proveniente de fontes tradicionais e incentivar a implantação de energia solar no sistema elétrico brasileiro, desenvolveu-se um programa que analisa a viabilidade técnico-econômica de inclusão do sistema fotovoltaico e fototérmico ao sistema tradicional de distribuição de energia nas diversas regiões do Brasil em residências, pois é o setor que possui um maior potencial de economia de energia. O programa é uma ferramenta de fácil manuseio, de acesso rápido que permitem tomadas de decisões rápidas e seguras quanto à implantação de energia solar por parte do consumidor, além de fornecer em qual região é mais viável essa implantação.
Abstract: In Brazil, due to a solid increasing in electrical energy demand at the last decades and due to the need to comply with this demand, became essential the inclusion of energetic efficiency programs and use of alternative energy resources in the Brazilian electrical supply system. However, the new hydro and thermo electrical power plants construction to attend the consumer cause strong environmental impacts, since they need big flooded lakes and eliminate theirs pollutants in the atmosphere, respectively. Moreover, the use of alternative energy resources decreases Brazil dependency of fossil fuels, besides it prevents the breakdown of the natural reserves and the need of energy importation, what would increase the charge for the electrical energy. To the energy conservation provided by traditional resources and to encourage the implementation of a solar energy based system in Brazil, it was developed a software that analyzes technical and economic feasibility of the photovoltaic and photothermical systems introduction in the traditional supply system on the several regions of Brazil to residential use, because this is a sector that has an elevated potential of energy saving. The software has a friendly interface, with quick access that allows the user to take quick and safe decisions, regarding to the solar energy implementation by consumers, and evaluate which area of the country is the most interesting to the implementation.
Mestre
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35

Close, Brett T. "Solar energy research and development in California." Pomona College, 2007. http://ccdl.libraries.claremont.edu/u?/stc,16.

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The energy crisis of 2001, high prices for gas and electricity and worries of climate change have caused a growing awareness about energy issues in California. The problems are clear. This paper looks at the next step of finding and implementing solutions. In this case the contribution that solar photovoltaic and solar thermal generation could make toward solving the problem. This paper looks at technological change, the current state of solar energy research, current government policies on solar energy, and finally makes policy recommendations to meet the stated problem.
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36

Mukhopadhyay, Boidurjo. "Solar energy based entrepreneurship and rural development : analysing institutional arrangements that support solar energy entrepreneurs in India." Thesis, University of Sussex, 2017. http://sro.sussex.ac.uk/id/eprint/68229/.

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Renewable energy (RE hereafter) has been observed as a potentially significant new source of jobs and rural growth in both OECD and BRICs countries, and a means of addressing environmental and energy security concerns. The global deployment of RE has been expanding rapidly. For instance, the RE electricity sector grew by 26% between 2005 and 2010 globally and currently provides about 20% of the world's total power (including hydro-power) (OECD, 2012). Rural areas attract a large part of investment related to renewable energy deployment, rending to be sparsely populated but with abundant sources of RE. Several case studies have found that RE deployment can provide hosting communities with some benefits including new revenue sources, new job and business opportunities, innovation in products/practices/policies in rural areas, capacity building and community empowerment, and affordable energy. There is a growing body of evidence on the instrumental role that entrepreneurs and small businesses play in driving local and national economies. The structure of rural economies is essentially composed of small enterprises, which are responsible for most of the job growth and the innovation. Rural development is a key element of strategies to reduce poverty and create income and employment opportunities (UNIDO, 2003). It is important to unleash and harness the creativity of grassroots entrepreneurs but they are posed with many challenges, the biggest being these grassroots inventions don't scale up. To overcome these challenges and promote rural entrepreneurship, support roles are required; this is also where the importance and role of institutions and their planned arrangements (for example, partnerships) are much debated in both domestic and international forums. This research investigates the current institutional arrangements that support solar entrepreneurship which creates solar energy based income-generating micro enterprises in rural India. In addition to that, it explores the wider implications on rural development that these entrepreneurships have while using these solar RETs. Institutions and individuals promoting rural development see entrepreneurship as a strategic development intervention that could accelerate the rural development process (Ezeibe, 2013). India, being the only country with a national ministry dedicated to RE initiatives (the MNRE, Government of India) and also ranking third on the renewable energy country attractiveness index (E&Y, 2013; 2016) makes an interesting country choice for investigation. The thesis applies a qualitative research method with an exploratory design to understand the interaction process between institutions and how different institutions support rural development to generate an in-depth analysis of existing institutions using a conceptual framework.
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37

Alghamedi, Ramzy. "Luminescent solar concentrator structures for solar energy harvesting and radiation control." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2017. https://ro.ecu.edu.au/theses/1965.

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Luminescent solar concentrators are devices capable of converting some spectral components of solar radiation by luminescence and concentrating them before collection by photovoltaic. The aim of this thesis is to design, develop and demonstrate the principle of all-inorganic semitransparent luminescent solar concentrator (LSC) structures capable of passing most of the visible light through to provide illumination, while reflecting more than 90% of the UV and IR radiations and scattering them to the edges of the glass where they are collected by PV cells to produce electricity. All-inorganic visibly-transparent energy-harvesting clear laminated glass windows are the most practical solution to boosting building-integrated photovoltaics (BIPV) energy outputs significantly while reducing cooling- and heatingrelated energy consumption in buildings. A typical semitransparent luminescent solar concentrator is based on the integration of micro-engineered optical structures, nano-materials and IR-selective thin-film coatings, to realise stable, long-lifetime and shatterproof clear glass panels. The ability of the proposed semitransparent luminescent solar concentrators to generate electricity addresses the future net-zero-energy building demand [1, 2], making them ideal candidates for future high-rise glass buildings. The developed semitransparent luminescent solar concentrators employ low-e thin films, which particularly, provide many benefits, including, (i) building overall aesthetic appearance, (ii) low glare and (iii) filtration of unwanted components of the incident sunlight thus increasing the energy saving rating of buildings. The low-e glass panes are typically used in a double glazing structure in order to protect the low-e film from environmental impacts and improve the insulation properties of the semitransparent luminescent solar concentrators in addition to reducing the energy consumed for cooling or heating the inside of buildings. Multi-layer thin film coatings for solar and thermal radiation control are designed, using the Optilayer software package, developed using Physical Vapour Deposition (PVD), and tested using spectrophotometry. Experimental results show that the measured transmittance spectra for the developed structures are in agreement with simulation results and demonstrate that with the use of optimum metal-dielectric layer combination it is possible to transmit/reflect arbitrary spectral components of the incident sunlight. In addition, two types of semitransparent luminescent solar concentrator structures are designed, developed and characterised, namely: 1. LSCs incorporating inorganic luminophore materials into the lamination interlayer. These luminophores, when used in conjunction with spectrally-selective low-e thin-film coatings and CuInSe2 solar cells, enable most of the visible solar radiation to be transmitted through the glass window with minimum attenuation and the ultraviolet (UV) radiation to be down-converted and routed together with a significant part of infrared radiation to the edges for collection by solar cells. 2. Advanced LSCs incorporating inorganic luminophore materials as well as spectrallyselective diffraction gratings as light deflector structures of high visible transparency into the lamination interlayer. For these LSCs, most of the visible solar radiation can be transmitted through the glass windows with minimum attenuation while the ultraviolet (UV) and a part of incident solar infrared (IR) radiation energy are converted and/or deflected geometrically for routing towards the vicinity of glass panel edge regions for collection by solar cells. To boost the solar concentration capability of the laminated glass panes, functionalized epoxy interlayers are especially developed, which comprise UV-curable epoxy and inorganic luminophores with engineered absorption and emission bands. The developed functionalized interlayers demonstrate an excellent ability to scatter and concentrate sunlight within the glass structure with minimum reabsorption. Several materials and combinations of several luminophore types were investigated in order to determine the optimum interlayer structure that exhibits maximum UV and IR radiation scattering, conversion, and deflection towards the edge solar cells. Measured conversion efficiencies of 3.8% and 5.4% are achieved for 10 cm × 10cm LSCs samples without and with diffraction gratings, which correspond to output electrical power densities of 38Wp/m2 and 54 Wp/m2,respectively. A photobioreactor based on the developed semitransparent luminescent solar concentrator technology is developed, in collaboration with Murdoch University, for microalgae growth. An Insulated Glass Units (IGU) employing a special low-e thin film is developed, which passes more than 50% of the visible light while blocking more than 90% of the UV and IR radiations, hence, reducing the temperature inside the photobioreactor and improving the microalgae growth. The growth and productivity of the microalgae in the Insulated Glass
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38

Liu, Suyao, and Li Xie. "Investigation of solar energy utilization in China." Thesis, Högskolan i Gävle, Akademin för teknik och miljö, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-14688.

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39

Ray, Mike C. T. "Solar Data Analysis." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1078.

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The solar industry has grown considerably in the last few years. This larger scale has introduced more problems as well as possibilities. One of those possibilities is analyzing the data coming from the sites that are now being monitored, and using the information to answer a variety of questions. We have four questions which are of prime importance identified in this thesis: 1. Can data from customers be trusted? 2. Can we use data from existing sites to determine which sites need the most improvement? 3. Can we implement a location-based algorithm to reduce the amount of false positives for performance, or other alarms? 4. Can we improve upon the current predicted power algorithm? We find that not only can we answer these questions definitively, but the improvements found are of significant value. Each of these items represents an important question that either directly or indirectly translates into increased revenue and engineering improvements for the solar industry as a whole.
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40

Perumattil, Jose Rose Mary. "The analysis of flat plate solar collector with double-axis solar tracking." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-38932.

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41

Montornès, Torrecillas Alex. "A study of the shortwave schemes in the Weather Research and Forecasting model." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/401501.

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The radiative transfer cannot be explicitly resolved in the atmospheric models for two reasons: i) a full treatment of the radiative transfer equation (RTE) requires a high amount of computational resources and ii) the radiative transfer fields such as the optical thickness are not a direct solution of the Euler equations and hence, they must be parameterized as a function of the meteorological fields. Consequently, the physical processes related with radiation are simplified and approximated in physical schemes. In the particular case of the solar radiation, the use of these parameterizations were reduced for many years to represent the day/night cycle inside the model. Therefore, the accuracy of the solar schemes was left in the background and the computational resources were prioritized. With the growth of the solar energy industry during the last decade, a paradigm shift has occurred. Now, the solar irradiance (i.e. global horizontal GHI, direct horizontal DHI and diffuse DIF) becomes an important product for resource assessment as well as for forecasting applications. The main objective of this thesis is the identification and quantification of the sources of error that have a direct or an indirect contribution to the accuracy of the solar schemes, particularly, in those available in the Weather Research and Forecasting (WRF-ARW) model, widely used in the sector. First, the thesis presents a review of the set of physical approximations considered in six solar parameterizations available in the WRF-ARW model: Dudhia, Goddard, New Goddard, Rapid Radiative Transfer Model for General Circulation Models (RRTMG), Climate Atmospheric Model (CAM) and Fu-Liou-Gu (FLG). The sources of error are limitations in the representation of the radiative transfer as a conse- quence of the set of approximations assumed by one scheme. In this thesis three sources of error are analyzed: i) errors due to the vertical discretization of the atmosphere in a set of layers that are assumed to be homogeneous (truncation error), ii) errors due to the misrepresentation of the layer between the top of the model (TOM) and the top of the atmosphere (TOA), called TOM error and iii) errors due to the physical simplifications and parameterizations in the RTE, named physical error. In order to avoid the uncertainty introduced by the other components of the model, the source code of each one of the six solar schemes has been separated of the model and adapted for working with 1-dimensional vertical profiles. The studies of the truncation and TOM errors are performed by using ideal vertical profiles under four scenarios: a dry atmosphere, a wet cloudless sky, low water cloud and a high ice cloud. The results for the ETOM show that for the typical range of TOM values in mesoscale appli- cations (i.e. 10 hPa), the error with respect to a full atmospheric column is less than 0.5% and hence, the TOM error can be neglected. The analysis of the Etrun reveals that the sensitivity of the solar schemes on the vertical config- uration (i.e. number of vertical levels and their distribution) is directly related with the method used for the vertical integration of the multiscattering processes. For the typical mesoscale config- urations, the Etrun under clear-sky conditions is determined around 1.1%, 0.9% and 4.9% for the GHI, DHI and DIF, respectively. In both cloudy scenarios, the Etrun increases significantly, being more important for the high clouds. The Ephys is analyzed under clear-sky conditions using real soundings from the Integrated Global Radiosonde Archive data-set and comparing the irradiance outcomes with the Baseline Solar Radiation Network measurements. With the exception of Dudhia, the behavior for all the parameterizations is the same. A large overestimation of the DHI with a large underestimation of the DIF that leads to a near-zero bias for the GHI. Polar sites show the lowest errors with a mean MAE of 2.1%, 5.2% and 3.7% for GHI, DHI and DIF, respectively. Midlatitude sites show the worst results with a mean MAE of 3.4% in GHI, 11.6% in DHI and 7.8% in the DIF.
L’objectiu principal d’aquesta tesi ´es la identificaci´o i quantificaci´o de les fonts d’error que tenen una contribuci´o directa o indirecta en la precisi´o dels esquemes solars, particularment en aquells disponibles en el model Weather Research and Forecasting (WRF-ARW), `ampliament emprat en el sector de l’energia solar. Les fonts d’error s´on limitacions en la representaci´o del transport radiatiu com a consequ¨`encia del conjunt d’aproximacions assumides per cada esquema. En aquesta tesi hi ha tres fonts d’error que s´on analitzades: i) l’error degut a la discretitzaci´o vertical de l’atmosfera en un conjunt d’estrats que s’assumeixen homogenis (error de truncament, Etrun), ii) l’error com a resultat d’una repre- sentaci´o insuficient de l’estrat entre el cim del model (TOM) i el cim de l’atmosfera (TOA), anomenat error de TOM Etom, i iii) l’error degut a les simplificacions i a les parametritzacions f´ısiques de l’RTE, definit com a error físic, Ephys. Per tal d’evitar la incertesa introdu¨ıda pels altres components del model, el codi font de cadas- cun dels sis esquemes solars ha estat separat del model i adaptat per treballar amb perfils verticals 1-dimensionals. Mitjan¸cant aquest m`etode, les habilitats dels esquemes solars poden ´esser anal- itzades sota condicions d’entrada id`entiques. D’una banda l’error de TOM i el de truncament s’analitzen a partir de perfils ideals. De l’altra, l’error f´ısic s’evalua prenent dades de radiosondatge com a perfil vertical i comparant les sortides dels esquemes radiatius amb mesures en superf´ıcie. Els resultats d’aquesta tesi mostren que l’Etom esdev´e negligible per la majoria d’aplicacions de mesoscala. Per configuracions t´ıpiques del model, l’Etrun en condicions de cel ser`e es troba al voltant de l’1.1%, el 0.9% i el 4.9% per la GHI, DHI i DIF, respectivament. En el cas amb nu´vols augmenta de forma significativa. L’estudi de l’Ephys mostra una relaci´o significativa amb el contingut de vapor d’aigua i els aerosols.
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42

Escobedo, João Francisco. "Refrigeração com uso de energia solar." Universidade de São Paulo, 1987. http://www.teses.usp.br/teses/disponiveis/54/54132/tde-28052009-094024/.

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Uma simulação numérica do ciclo de refrigeração a adsorção é realizada para os pares zeólita-água e carvão ativo AC-35 metanol, justificando a escolha do par bem como do sistema de captação a serem utilizados no protótipo. O protótipo construído compreende um concentrador cilíndrico-parabólico com rastreamento solar, um tubo de calor e uma unidade frigorífica (com zeólita-água). Aspectos tecnológicos como válvulas, soldas e carregamento do par na máquina são analisados. Os resultados dos testes de desempenho são apresentados, discutidos e comparados com a literatura. Uma análise de custos é feita. Paralelamente, construímos termo pilhas pelo método da evaporação. Estas termopilhas foram utilizadas na construção do piranômetro e do pireliômetro. Os instrumentos são caracterizados em termos de sensibilidade, constante de tempo, linearidade, efeitos de temperatura e convecção natural. Os resultados desta caracterização são discutidos e comparados com um modelo fabricado pela Eppley. Finalmente, no apêndice I, testamos o desempenho de um coletor plano utilizando no absorvedor o revestimento seletivo de óxido de alumínio recentemente desenvolvido no IFQSC. As melhores condições para obtenção do revestimento seletivo em placas de grande porte são estudadas.
A numerical simulation of the adsorption refrigeration cycle was made for zeolite/water and activated carbon(AC-35)/ methanol pairs, to select the pair and the solar collector in the prototype. The fabricated prototype consists of a cylindrical paraolic concentrator with solar trackins, a heat pipe and the refrigeration unit (with the zeolite/water pair). The technical aspects of values, welds and out-gassing are analyzed. The results of the performance tests are presented, discussed and compared with the literature. An analysis of costs is made. In parallel thermopiles were constructed using the evaporation method. These thermopiles were used in the construction of the piranometer and the pirheliometer. The instruments were characterized in terms of: sensitivity, stability with time, linearity, effects of temperature and natural convenction. The results of this characterization are discussed and compared with a model made by Eppley. Finally, in Apendix I, we tested the performance of a flat plate collector using a selective coating of aluminium oxide (developed in IFQSC) as absorber. The Best conditions for obtaining the seletive coating on big size plates are discussed.
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43

Claudino, Filho Vicente de Vasconcelos. "Desenvolvimento de um coletor Fresnel para sistema de climatização dessecante." Universidade Federal da Paraíba, 2016. http://tede.biblioteca.ufpb.br:8080/handle/tede/8678.

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Brazil has as a main source for production of electricity the dams using water to drive the turbines and as a secondary source are used the thermoelectric power plants that use fuel oil for electric power production. Both generate a large environmental impact, due to the fact of the dams need huge areas for its construction, which often leads to destruction of important ecosystems in the region where it will be installed the hydroelectric plant, besides the fact that they need the rainfall cycle so that the dams have the operating capacity, while the thermoelectric power plants burn fossil fuels thus increasing emissions of CO2 to the atmosphere. An alternative to the solution of the problems mentioned above is the use of renewable sources of energy, with emphasis on this work. Solar energy can be divided into two parts: thermal and photovoltaic. This work it is focused on thermal use of solar energy, with a Fresnel-type solar concentrator to heat water, which will trigger a cooling system environment with the use of desiccant rotors. The choice of type Fresnel collector gave the field of development of this hub is still in constant growth and by the fact that even occupy a relatively small area when compared to other solar thermal concentrators, in addition to its construction be simple and low cost when again compared to other solar concentrators.
O Brasil tem como fonte principal para produção de energia elétrica as hidrelétricas que utilizam água para movimentar as turbinas e como fonte complementar são utilizadas as termoelétricas que usam óleo combustível para produção de energia elétrica. Ambas geram um grande impacto ambiental, devido ao fato das hidrelétricas necessitarem de enormes áreas para a construção das represas, o que muitas vezes acarreta na destruição de ecossistemas importantes para a região onde irá ser instalada a hidrelétrica, além do fato que elas necessitam do ciclo das chuvas para que as represas possuam capacidade de operação, enquanto que as termoelétricas queimam combustíveis fosseis, aumentando assim as emissões de CO2 para a atmosfera. Uma alternativa para a solução dos problemas citados anteriormente é a utilização de fontes renováveis de energia, dando ênfase neste trabalho a energia solar. A energia solar pode ser dividida em duas vertentes: térmica e fotovoltaica. Este trabalho está voltado para a utilização térmica da energia solar, através da utilização de um concentrador solar do tipo Fresnel para o aquecimento de água, a qual irá acionar um sistema de refrigeração de ambientes com a utilização de rotores dessecantes. A escolha do coletor do tipo Fresnel se deu pelo campo de desenvolvimento deste concentrador estar ainda em constante crescimento e pelo fato do mesmo ocupar uma área relativamente pequena quando comparado com outros concentradores solares térmicos, além de sua construção ser simples e de baixo custo quando novamente comparada a outros concentradores solares.
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44

Niaparast, Shervin. "ENERGY ANALYSIS OF A SOLAR BLIND CONCEPT INTEGRATED WITH ENERGY STORAGE SYSTEM." Thesis, KTH, Kraft- och värmeteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-131419.

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The use of an attached sunspace is one of the most popular passive solar heating techniques. One of the main drawbacks of the sunspace is getting over heated by the sun energy during the hot season of the year. Even in northern climates overheating could be problematic and there is a considerable cooling demand. Shading is one of the most efficient and cost effective strategies to avoid overheating due to the high irradiation especially in the summer. Another strategy is using ventilation system to remove the excess heat inside the sunspace. However this rejected energy can be captured and stored for future energy demands of the sunspace itself or nearby buildings. Therefore the Solar blind system has been considered here for the shielding purpose in order to reduce the cooling demand. By considering the PV/T panels as the solar blind, the blocked solar energy will be collected and stored for covering part of the heating demand and the domestic hot water supplies of the adjacent building.  From a modeling point of view, the sunspace can be considered as a small-scale closed greenhouse. In the closed greenhouse concept, available excess heat is indeed utilized in order to supply the heating demand of the greenhouse itself as well as neighboring buildings. The energy captured by PV/T collectors and the excess heat from the sunspace then will be stored in a thermal energy storage system to cover the daily and seasonal energy demand of the attached building. In the present study, a residential building with an attached sunspace with height, length and width of 3, 12 and 3.5 meters respectively has been assumed located in two different locations, Stockholm and Rome. Simulations have been run for the Solar blind system integrated with a short-term and a long-term TES systems during a year to investigate the influence of the sunspace equipped with a PV/T Solar blind on the thermal behavior of the adjacent building. The simulated results show that the Solar blind system can be an appropriate and effective solution for avoiding overheating problems in sunspace and simultaneously produce and store significant amount of thermal energy and electricity power which leads to saving considerable amount of money during a year.
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45

Kang, Ji-Hwan. "Energy transfer enhancement of photon upconversion systems for solar energy harvesting." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45846.

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Photon energy upconversion (UC), a process that can convert two or more photons with low energy to a single photon of higher energy, has the potential for overcoming the thermodynamic efficiency limits of sunlight-powered devices and processes. An attractive route to lowering the incident power density for UC lies in harnessing energy transfer through triplet-triplet annihilation (TTA). To maximize energy migration in multicomponent TTA-assisted UC systems, triplet exciton diffusivity of the chromophores within an inert medium is of paramount importance, especially in a solid-state matrix for practical device integration. In this thesis, low-threshold sensitized UC systems were fabricated and demonstrated by a photo-induced interfacial polymerization within a coaxial-flow microfluidic channel and in combination with nanostructured optical semiconductors. Dual-phase structured uniform UC capsules allow for the highly efficient bimolecular interactions required for TTA-based upconversion, as well as mechanical strength for integrity and stability. Through controlled interfacial photopolymerization, diffusive energy transfer-driven photoluminescence in a bi-molecular UC system was explored with concomitant tuning of the capsule properties. We believe that this core-shell structure has significance not only for enabling promising applications in photovoltaic devices and photochromic displays, but also for providing a useful platform for photocatalytic and photosensor units. Furthermore, for improving photon upconverted emission, a photonic crystal was integrated as an optical structure consisting of monodisperse inorganic colloidal nanoparticles and polymer resin. The constructively enhanced reflected light allows for the reuse of solar photons over a broad spectrum, resulting in an increase in the power conversion efficiency of a dye-sensitized solar cell as much as 15-20 %.
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46

Brito, Jose Clet. "Estudo sobre piscina solar." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263402.

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Orientador: Kamal Abdel Radi Ismail
Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: Neste trabalho apresentamos um estudo sobre piscina solar, como retentora de energia térmica, para futura transformação em energia elétrica, sendo esta constituída por 03 camadas de água salgada com gradientes de densidades diferentes e em ordem crescente de cima para baixo, fazendo com que obtivéssemos 03 temperaturas também em ordem crescente. Fizemos o seu monitoramento durante onze dias, e os dados obtidos nos ensaios permitiram uma análise das diferenças entre as temperaturas final e inicial, da zona de armazenamento, zona intermediária, zona de superfície e o rendimento ao longo dos onze dias no intervalo de tempo das 8:00h. às 17:00h., conforme mostra as tabelas 4.1 a 4.12. A apresentação dos resultados em forma de gráfico é muito importante, pois permite extrair com mais realidade os parâmetros que descrevem, de forma simples, o omportamento da piscina solar de gradiente salino. As variações de temperatura de cada zona, para melhor visualização gráfica, são apresentadas nos gráficos 4.1 a 4.11, sendo nas ordenadas as temperaturas médias e nas abscissas os tempos. E, no gráfico 4.12, o rendimento em função da temperatura média. Após a realização dos ensaios, os pontos foram plotados, gerando os gráficos 4.1 a 4.12. Utilizamos o valor médio diário da radiação solar incidente, como sendo 837,34W/m2, segundo dados da Tese de Mestrado de LOPES, (2004), para latitude de 2,55º em relação a linha do equador em São Luís do Maranhão e a potência total disponível de 164,41W. Os dados experimentais informam que a temperatura máxima da zona de armazenamento foi obtido no 2º ensaio, correspondendo a 45ºC e sua eficiência máxima de 13,09%, obtido no 5º ensaio, com intervalo de confiabilidade, respectivamente iguais a [4,26 ; 8,26]% e [5,16 ; 6,32]ºC, conforme demonstrativo nos apêndices: D.2.10.2 e D.5.8.2
Abstract: In this work we present a study on solar swimming pool, as retainer of thermal energy, for future transformation in electric energy, being this consisting by 03 salty with gradients of different densities and orderly water layers increasing from top to bottom, making with that we also got 03 temperatures orderly increasing. We made its monitoramento during eleven days, and the data gotten in the assays had allowed an analysis of the differences between the temperatures final and initial, of the zone of storage, intermediate zone, zone of surface and the income to the long one of the eleven days in the interval of time of 8:00h. to 17:00h., as it shows to tables 4,1 the 4.12. The presentation of the results in graph form is very important, therefore it allows to extract with more reality the parameters that they describe, of simple form, the behavior of the solar swimming pool of saline gradient. The variations of temperature of each zone, for better graphical visualization, are presented in graphs 4,1 the 4,11, being in commanded the average temperatures and the abscissas the times. E, in the graph 4,12, the income in function of the average temperature. After the accomplishment of the assays, the points had been located, generating graphs 4,1 the 4.12. We use the daily average value of the incident solar radiation, as being 837,34W/m2, according to data of the Thesis of Mestrado of LOPES, (2004), for latitude of 2,55º in relation the line of the equator in São Luís of the Maranhão and the available total power of 164,41W. The experimental data inform that the maximum temperature of the storage zone was gotten in 2º assay, corresponding 45ºC and its maximum efficiency of 13,09%, gotten in 5º assay, with trustworthiness interval, respectively equal [ 4,26; 8,26]% and [ 5,16; 6,32]ºC, as demonstrative in the appendices: D.2.10.2 and D.5.8.2
Mestrado
Instrumentação e Controle Industrial
Mestre em Engenharia Mecânica
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47

Arthur, A. C. "A novel solar-savings fraction prediction methodology for integral passive solar water heaters." Thesis, Cranfield University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.237552.

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48

Alves, Alceu Ferreira [UNESP]. "Desenvolvimento de um sistema de posicionamento automático para painéis fotovoltaicos." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/101817.

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A necessidade de oferecer alternativas para energização de propriedades rurais de pequeno porte com eficiência, confiabilidade e custo acessível, motivou a realização desta pesquisa, cujo enfoque principal foram os sistemas fotovoltaicos e a busca por um melhor desempenho destes sistemas a partir de estratégias de posicionamento dos painéis solares em direção ao Sol. Este trabalho apresenta o desenvolvimento experimental de um conjunto posicionador automático para módulos fotovoltaicos e a avaliação do funcionamento deste conjunto considerando-se o aumento na geração de energia elétrica em função da complexidade de implementação e do consumo de energia pelo próprio sistema de movimentação, além de seus custos de implantação. Foi projetado e implementado um dispositivo eletromecânico simplificado, capaz de sustentar e movimentar um módulo fotovoltaico ao longo do dia e ao longo do ano, sempre mantendo sua superfície direcionada em posição perpendicular aos raios solares incidentes. Utilizaram-se motores de passo, controlador lógico programável e componentes de baixo custo, que resultaram em um conjunto de manutenção simplificada,sem uso de sensores e com otimização dos movimentos, devido ao ajuste de inclinação do painel ser realizado somente uma vez ao dia. A avaliação do ganho na geração de energia elétrica baseou-se na coleta dos dados elétricos (tensão e corrente) e ambientais (insolação e temperatura) de dois sistemas fotovoltaicos com as mesmas características, instalados lado a lado, sujeitos às mesmas condições de insolação, temperatura e carga elétrica, sendo um fixo e outro móvel. A partir dos resultados obtidos concluiu-se pela viabilidade da proposta, não apenas pelo êxito no aumento da geração de energia, mas também pela boa relação custo/benefício, indicando que o sistema posicionador desenvolvido mostra-se vantajoso...
The need to offer alternatives of electricity supply to the small rural properties, providing them with efficiency, reliability and accessible cost, has motivated the development of this research, whose main approach was photovoltaic systems and the search for better performance of these systems with the solar panels positioning toward the sun. This work presents the experimental development of an automatic positioning system for photovoltaic modules and the evaluation of this system’s behavior taking in account the increase in generation of electric energy as a function of the complexity of implementation and the consumption of energy by the movement system itself, and its costs of implantation also. It was designed and built a simplified electromechanical device, which is able to support and to move a photovoltaic module along the day and along the year, always keeping its surface aimed to the sun rays. Stepper motors, programmable logic controller and low cost components were used, and these have resulted on a simplified maintenance set, with no sensors and optimization of movements, due the adjustment of panel’s inclination take place only once a day. The methodology adopted to evaluate the gain in the electricity generation was based on the acquisition of electrical data (voltage and current) and environmental data (insolation and temperature) from two photovoltaic systems whose have identical physical and electrical characteristics and were installed side by side, submitted to the same conditions of insolation, temperature and electric load. One of the solar panels was mounted on a fixed mechanical structure, and the other one on a mobile structure.The obtained results demonstrate the feasibility of the proposed mobile system, not only because of the real increase observed in electric energy generation, but also by the excellent cost effectiveness obtained... (Complete abstract click electronic access below)
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49

Oliveira, Táyzer Damasceno. "Facades and solar parking yield estimation at Ultrecht University." Master's thesis, Universidade de Évora, 2020. http://hdl.handle.net/10174/26741.

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Solar energy born as one of the ways to produce energy using renewable resources (like wind, biomass, hydraulic, geothermal and wave energies). The solar energy is divided into three types: thermal, that generates heat (which can be used to produce energy), photovoltaic that only produces electricity and PVT, a hybrid way to generate heat and produce electricity. Photovoltaic (PV) technologies have several uses such as lighting, satellites, solar home systems, pumping, etc. This work pretends to estimate the potential of usage of solar cells and the yield potential at De Uithof campus located in Utrecht, Netherlands. Building attached photovoltaic (BAPV), solar parking lot and charging electric vehicles (EV) were the chosen uses of solar energy for this project. The work method is divided into four parts, firstly a 2D part that was done on ArcGIS software to create the shapefile with the buildings and solar parking information of the incoming radiation for the entire year in Wh/m2. Secondly, the 3D works on AutoCAD, Autodesk FBX Converter and PVsyst to create the 3D plant and to import the shading scene construction, to install the solar modules on the roofs, facades and solar parking lot. The third part is to choose the charging mode 3 combined with connector type 2 that full charge the Tesla model 3 (which has a battery of 50 kWh) in around five hours (charging 11kW per hour). The fourth part details the input data and calculate the economic viability considering the total cost of initial investment and operation/maintenance costs. Two tests were used to compare different options, VC0 (35.175 kWp) with the solar modules facing south and VC1 (50.796 kWp) on the west-east plus south direction. The chosen PV module was the LG 340 N1C-A5 by LG Electronics and the inverter was the AGILO 100.0-3 Outdoor by Fronius International because they are commercially available equipments. The VC0 has a system production of 27.229 MWh/year and the VC1, 35.285 MWh/year, both are feasible economically because they have the NPV greater than zero, being €68 million for VC0 and €83 million for VC1. In addition, the Payback is much lower than 25 years (lifetime of photovoltaic panels), being 7,69 years and 7,03 years, respectively for VC0 and VC1. Furthermore, the LCOE of the VC0 is 0.058 €/kWh, and for VC1, 0,064 €/kWh; RESUMO: A energia solar surgiu como uma das diversas maneiras para produzir energia elétrica utilizando recursos renováveis (como a energia eólica, biomassa, hidráulica, geotérmica e das ondas). A energia solar é dividida em três tipos: térmica, que gera calor (que também pode ser usado para produzir energia), fotovoltaica que somente produz eletricidade e PVT, maneira híbrida de gerar calor e produzir eletricidade. Tecnologia fotovoltaica tem diversos usos como iluminação, satélite, sistemas solares residenciais, bombeamento, entre outros. Este trabalho pretende estimar o potencial do uso de células solares e a potência anual no campus De Uithof que se localiza em Utrecht, Países Baixos. Building attached photovoltaic (BAPV), estacionamento solar e carregamento de veículos elétricos (EV) foram os usos da energia escolhidos para este projeto. O método do trabalho se divide em quarto partes, primeiramente a parte 2D que foi feita no software ArcGIS para criar shapefile com as informações da radiação que chega aos prédios e estacionamento durante todo o ano em Wh/m2. Segundamente, o 3D feito no AutoCAD, Autodesk FBX Converter e PVsyst para criar a planta 3D e importar no Shading scene construction, instalar os módulos solares nos telhados, fachadas e estacionamento solar. A terceira parte foi escolher o modo de carregamento 3 combinado com o conector 2 que carrega completamente o Tesla model 3 (possuindo bateria de 50 kWh) em aproximadamente em cinco horas (carregando 11 kW por hora). A quarta parte detalha os dados de entrada e calcula a viabilidade econômica considerando o custo total de investimento e custos de operação/manutenção. Dois testes foram feitos de modo a compará-los, VC0 (35.175 kWp) com os módulos solares virados para sul e VC1 (50.796 kWp) nas direções este-oeste e direção sul. O painel escolhido foi o LG 340 N1C-A5 da LG Electronics e o inversor AGILO 100.0-3 Outdoor da Fronius International porque são equipamentos comerciais. A produção do VC0 é de 27.229 MWh/ano e o VC1, 36.614 MWh/ano, os dois são economicamente viáveis porque possuem o VPL (NPV) maior que zero, sendo €68 millhões para o VC0 e €83 para o VC1. Adicionalmente, o Payback possui um valor bem abaixo de 25 anos (ciclo de vida dos paineis fotovoltaicos), sendo 7,69 anos e 7,03, respe.
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50

Canto, Mario Afonso Ribeiro do. "Projeto e desenvolvimento de um sistema automatizado para monitoramento de fontes alternativas de energia /." Guaratinguetá : [s.n.], 2007. http://hdl.handle.net/11449/99291.

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Abstract:
Orientador: Teófilo Miguel de Souza
Banca: Samuel Euzedice de Lucena
Banca: Osiris Canciglieri Junior
Resumo: A utilização de fontes alternativas e renováveis de energia apresenta-se como um recurso energético com um mínimo de impacto ambiental. Com o crescimento do uso destes recursos, torna-se importante o conhecimento dos mesmos do comportamento em relação às condições ambientais naturais. As alterações das condições climáticas, por vezes, causam incertezas quanto ao rendimento dos sistemas alternativos e renováveis de geração de energia. Este trabalho apresenta-se como uma forma de conhecimento do comportamento das fontes de energia perante diversas condições do clima. Esta dissertação tem por objetivo contribuir com o conhecimento sobre o comportamento de fontes alternativas de energia comerciais e desenvolvidas no Centro de Energias Renováveis da UNESP de Guaratinguetá. Neste trabalho, foi desenvolvido um sistema de aquisição e tratamento de dados para monitorar o comportamento de fontes alternativas e renováveis de energia e das condições ambientais. Nesse sistema são especificados sensores para monitoramento das condições ambientais e para monitoramento dos dispositivos componentes das fontes de energia alternativa. O desenvolvimento de um software para coleta de dados e controle dos dispositivos de medição é parte integrante do trabalho para viabilizar o acesso às informações de forma a facilitar a análise de resultados. O protótipo construído durante o desenvolvimento da dissertação possibilitou o monitoramento das fontes de energia do laboratório como também das condições atmosféricas locais.
Abstract: The renewable and alternative energy sources utilization presents-itself as an energy resource with a minimum environmental impact. With the growth of the use of these resources, becomes so important the knowledge of the performace regarding to the natural environmental conditions. The climatic conditions alterations, for times, cause users doubts of confidance of the renewable and alternative systems performance in energy generation. This work presents-itself as a form of knowledge of the performance of the energy sources to diversiity climate conditions. This dissertation has for objective contribute with the knowledge about the performance of commercial and alternative energy sources and developed in the Renewable Energies Center of the UNESP, Guaratinguetá. Was developed a system of data acquisition and analysis for monitoring renewable and alternative energy sources and environmental conditions. In this work, are determined and specified sensors for monitoring of the environmental conditions and for monitoring of the devices components of the alternative energy.sources The development of a data aquisition software and control of measurement is a part to make easy the access the information to facilitate the results analysis. The prototype built during the dissertation development enabled the energy sources monitoring of the center as also of the local atmospheric conditions.
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