O trabalho apresenta o desenvolvimento de células solares fotoeletroquímicas baseadas na sensibilização de n-TiO2 por corantes sintéticos e naturais. Abrange as etapas envolvidas na sua obtenção, desde a preparação dos compostos sensibilizadores, filmes semicondutores e meio eletrolítico, até a montagem e medidas de eficiência, com a otimização dos diversos componentes do sistema, num arranjo do tipo sanduíche. O fotoanodo consiste num filme de TiO2 nanocristalino sensibilizado pelo corante num substrato condutor. O contraeletrodo é composto de um substrato condutor recoberto com camada transparente de platina. Entre os eletrodos é disposta a camada de eletrólito, geralmente solução de l2/Lil em acetonitrila. A espessura do filme de semicondutor é controlada com os métodos empregados na deposição de sua dispersão. A transparência final depende ainda do método de preparação das dispersões. Utilizando as espécies cis-[(dcbH2)2RuLL\')2+, dcbH2 = 4,4\'-(CO2H)2-2,2\'bipiridina e L/L\' = cianopiridina, quinolina e H2O, como sensibilizador, obteve-se conversão eficiente de luz visível em eletricidade com valores de IPCE de até 50 % entre 400 e 550 nm. Os processos de transferência e recombinação de elétron na interface sensibilizador/semicondutor foram investigados por experimentos com técnicas resolvidas no tempo empregando sensibilizadores ancorados aos filmes transparentes de TiO2. O trabalho envolveu ainda incorporações técnicas para aumentar a eficiência da célula, como filamentos metálicos protegidos e a combinação de unidades independentes numa associação modular, que são objetos de patentes depositadas. / This work presents the development on photoelectrochemical solar cells based on sensitization of n-TiO2 by synthetic and natural dyes. It comprises several steps involved in the fabrication and assembling of the cells in a sandwich-type design. Preparation of sensitizers, semiconductor films and electrolyte media, as well as efficiency measurements and optimization of several components are presented. The photoanode consists of a dye-sensitized nanocrystalline n-TiO2 film onto a conductive substrate. The counterelectrode is a conductive substrate covered with a thin, transparent platinum layer. The electrolyte layer, usually l2/Lil in acetonitrile, is placed between the electrodes. The deposition process of the semiconductor dispersion onto the substrates regulates the resulting thickness of the film. The final transparency is also controlled by the procedure employed in the preparation of the semiconductor dispersion. The species cis-[(dcbH2)2RuLL\']2+, dcbH2 = 4,4\'-(CO2H)2-2,2\'-bipyridine and L/L\' = 4-cyanopyridine, quinoline and H2O, were employed as sensitizers resulting in IPCE (Incident Monochromatic Photon to Current Conversion Efficiency) values as high as 50 % from 400 to 550 nm. Electron transfer and recombination processes across the semiconductor/sensitizer interface were investigated with time-resolved experiments employing transparent films of n-TiO2 sensitized by the anchored species. Other approaches aiming improvements in efficiencies and the preparation of photoelectrochemical solar cells for different applications or through environmentally friendly processes are discussed. The use of protected metallic filaments and the modular arrangement of single cells are issues of patents.

Esta pesquisa de mestrado apresenta um estudo, baseado em corpus comparável, da terminologia da energia solar fotovoltaica (conversão direta da radiação solar em eletricidade) em português do Brasil e francês da França. A importância das novas tecnologias de obtenção de energia, a partir de fontes limpas e renováveis, tal como a energia solar fotovoltaica, leva à publicação de livros, manuais técnicos, catálogos, contratos, diferentes tipos de discurso nos quais se encontra a linguagem técnica da área. Esses textos especializados acabam chegando até o tradutor que, diante da tarefa de compreender os termos e versá-los para outra língua, necessita recorrer a materiais de referência, como dicionários técnicos e bancos de dados especializados. Considerando, assim, a importância dos estudos terminológicos e da compilação de materiais terminográficos monolíngues e bilíngues das mais diversas áreas do conhecimento, realizamos um estudo da terminologia da energia solar fotovoltaica fundamentado na Teoria Comunicativa da Terminologia (CABRÉ, 1999) com o auxílio das ferramentas de análise de corpora proporcionadas pela Linguística de Corpus (ANTHONY, 2014). O corpus de estudo é composto por textos escritos por especialistas da área em português do Brasil e em francês da França, dos quais foram coletados 433 termos simples e complexos, sendo 242 em português e 191 em francês. Pela análise dos contextos de uso dentro do corpus e em materiais de apoio, buscamos pelos ganchos terminológicos (DUBUC, 1985), traços descritores que permitem a verificação das relações de sinonímia e de equivalência mantidas entre as unidades terminológicas. Foram elaboradas fichas terminológicas, para fins terminográficos, nas quais figuram uma definição e exemplos (PAVEL; NOLET, 2002) para cada termo. A partir dessas fichas, será possível elaborar, na continuação da pesquisa num futuro próximo, um dicionário de energia solar fotovoltaica, o qual poderá auxiliar tradutores no processo tradutório de textos especializados da área. / The masters research herein provides a study based on a comparable corpus of photovoltaic solar energy terminology (direct solar radiation conversion into electricity) of Portuguese from Brazil and French from France. The importance of new energy generation technologies from clean and renewable sources, such as photovoltaic solar energy, leads the publication of books, technical manuals, catalogs, contracts, different types of text in which one can find the technical discourse of the field. These specialized texts reach the translator who, before having to understand the terms and translate them into another language, need to resort to reference materials, such as technical dictionaries and specialized database. Accordingly, considering the importance of terminological studies and the compilation of monolingual and bilingual terminographic material from the most varied fields of knowledge, a study of the photovoltaic solar energy terminology based on the Communicative Theory of Terminology (CABRÉ, 1999) was carried out, with the help of corpus analysis tools provided by Corpus Linguistics (ANTHONY, 2014). The corpus studied consists of texts written by experts in the field in Portuguese from Brazil and French from France, from which 433 simple and complex terms were collected: 242 terms in Portuguese and 191 in French. By analyzing usage contexts within the corpus and support materials, we searched in textual matches (DUBUC, 1985) for descriptive traits, which allow verifying the relation of synonymy and equivalence maintained among terminological units. Terminology records were created for terminographic purposes, featuring a definition and examples (PAVEL; NOLET, 2002) for each term. With these records, we will be able to compile, in a short future, a dictionary of photovoltaic solar energy which will help translators in the translating process of specialized texts from such field.

Energy poverty and lack of access to electricity is a global problem which is recognised in the sustainable development goal 7. Today 1.2 billion people live without access to electricity and most of them are situated in Sub-Saharan Africa where biomass still constitutes the main source of energy. Rural areas are unproportionally affected by this throughout SSA since grid-extension has been slow and most rural dwellers are not connected to any form of electricity grid. Extending the grid to more isolated rural areas may however be economically and politically infeasible which is why off-grid solutions is an attractive solution to close the energy poverty gap. Off-grid solar energy has during recent years been increasingly promoted as viable solution to provide clean, affordable and accessible energy to rural households in SSA. While there is extensive research available on the economic feasibility and socioeconomic impacts of off-grid solar energy, there has been limited research with explicit focus on how livelihoods of rural households in SSA have been impacted from a sustainable livelihood perspective. This case study on Tanzania argues that the sustainable livelihoods perspective is crucial in getting a holistic understanding of how off-grid solar energy has impacted rural households in SSA. Through qualitative interviews with a number of households, businesses and social services in three rural villages located in the Tanga region, this study found that off-grid solar energy overall seemed to have a positive impact on the communities and the livelihoods of individual households. However, some concerns are also raised with the sustainability of off-grid solar energy. While it has great recognised potential and direct impact, some key challenges were identified as issue of energy security for the household and concerns of economic feasibility in the solar energy sector.

"Asphalt pavements are made up of several layers of materials and different types of materials are being used as base courses in these pavements. The properties of these pavement layers are affected significantly by temperature, and all of the layers are made up of heterogeneous mixtures of a wide variety of materials whose thermal properties are not readily available. Therefore, laboratory experiments were carried out with samples of pavements with different base course materials to determine temperature profiles along the depth, and finite element analysis was used to backcalculate thermal properties of the materials in the different layers of the different samples. The concept of extracting heat energy from asphalt pavements was evaluated by finite element modelling and testing small and large scale asphalt pavement samples. Water flowing through copper tubes inserted within asphalt pavements samples were used as heat exchangers in the experiments. The rise in temperature of water as a result of flow through the asphalt pavement was used as the indicator of efficiency of heat capture. The results of small scale testing show that the use of aggregates with high conductivity can significantly enhance the efficiency of heat capture. The efficiency can also be improved by using a reflectivity reducing and absorptivity increasing top layer over the pavement. Tests carried out with large scale slabs show that a larger surface area results in a higher amount of heat capture, and that the depth of heat exchanger is critical Heat-Islands are formed as a result of construction that replaces vegetation with absorptive surfaces (asphalt pavement). One suggested method to reduce the emitted heat from asphalt pavement surfaces is to reduce the temperature of the surface by flowing a suitable fluid through the pavement. Laboratory experiments were carried out using hand-compacted hot mix asphalt samples with quartzite and metagranodiorite aggregates. Pipes with different surface area were used to flow water through the samples, and the processes were modeled using finite element method. The results clearly show the feasibility of the proposed method, and indicate the beneficial effects of higher thermal conductivity of aggregates and larger surface area of pipes. "

Thesis (M.Sc.Eng.) PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / Electrodynamic Shields (EDS) have been targeted as a technology to help mitigate degradation of power output caused by dust deposition on various solar collectors. Though printed circuit board based EDS prototypes have shown promising dust removal efficiencies, an inexpensive method of transparent EDS fabrication must be realized before the EDS technology is adopted by the solar industry. Development of a screen-printing process is presented as a scalable, low-cost method of EDS fabrication. The process is established using a silver-based ink on borosilicate glass substrates and then adapted to incorporate transparent conductive PEDOT:PSS and ITO nanoparticle solutions. Successful EDS prototypes are characterized and integrated with photovoltaic cells and second surface mirrored substrates. Removal efficiencies of the screen-printed EDS are tested by measuring the restoration in specular reflection and transmission in integrated EDS-mirror and EDSPV modules after dust depositions. Finally, a cost analysis of the EDS screen-printing process is performed in order to predict the economic viability of the EDS technology when used in conjunction with solar collecting technologies. / 2031-01-01

Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2018-12-14T13:01:07Z No. of bitstreams: 1 Eduardo José Stolf_.pdf: 949489 bytes, checksum: c0ec8429474039f1cbc9b7a83386a603 (MD5) / Made available in DSpace on 2018-12-14T13:01:07Z (GMT). No. of bitstreams: 1 Eduardo José Stolf_.pdf: 949489 bytes, checksum: c0ec8429474039f1cbc9b7a83386a603 (MD5) Previous issue date: 2018-08-20 / UNISINOS - Universidade do Vale do Rio dos Sinos / Com as recentes crises hídricas ocorridas no Brasil, os consumidores de energia elétrica residencial, podem buscar outras tecnologias para o fornecimento, como é o caso da energia solar fotovoltaica. Além disso, a questão econômica e ambiental faz com que seja crescente o interesse nas chamadas tecnologias verdes de geração de energia. Neste sentido, a energia solar fotovoltaica é considerada uma das tecnologias energéticas mais promissoras por especialistas no mundo todo, porém a adoção da energia solar fotovoltaica no Brasil, ainda representa uma parcela muito pequena na fonte energética nacional. Portanto, neste estudo, se explorou fatores influenciadores que têm um efeito significativo sobre as intenções de uso de usar esta nova tecnologia. Foram relacionados os fatores orientação para inovação, consciência ambiental, qualidade do sistema, confiança percebida, conhecimento, para determinar a atitude e intenção de uso da energia solar fotovoltaica. Diante deste contexto, este estudo tem como objetivo propor e testar um modelo teórico para analisar alguns fatores influenciadores para a adoção da energia solar fotovoltaica. Para alcançar este objetivo, foi coletado dados através de uma survey com 420 respondentes. Após, os resultados foram analisados por meio de um método de modelagem de equações estruturais ao modelo de pesquisa proposto. Esta pesquisa indicou que três fatores positivos, que compreendem a orientação para inovação, consciência ambiental e a qualidade do sistema, contribuem significativamente para determinar a atitude do público em relação à tecnologia de energia solar fotovoltaica. A intenção de usar a tecnologia também foi determinada por três variáveis positivas (atitude, confiança percebida e conhecimento). Com isto, todas as hipóteses propostas neste modelo conceitual foram confirmadas. Com base em achados empíricos deste estudo, as implicações e sugestões são apresentadas e discutidas neste trabalho. / With recent water crises in Brazil, consumers of residential electricity may seek other technologies for supply, such as solar photovoltaic energy. In addition, the economic and environmental issue makes increasing interest in so-called green energy generation technologies. In this sense, photovoltaic solar energy is considered one of the most promising energy technologies by experts worldwide, but the adoption of photovoltaic solar energy in Brazil still represents a very small share of the national energy source. Therefore, in this study, we explored influencing factors that have a significant effect on the intentions of using this new technology. The orientation factors for innovation, environmental awareness, quality of the system, perceived trust, knowledge, to determine the attitude and intention to use solar photovoltaic energy were related. In this context, this study aims to propose and test a theoretical model to analyze some influencing factors for the adoption of photovoltaic solar energy. To achieve this goal, data were collected through a survey of 420 respondents. Afterwards, the results were analyzed through a structural equation modeling method to the proposed research model. This research indicated that three positive factors, which include the orientation towards innovation, environmental awareness and the quality of the system, contribute significantly to determine the attitude of the public in relation to photovoltaic solar energy technology. The intention to use technology was also determined by three positive variables (attitude, perceived confidence and knowledge). With this, all the hypotheses proposed in this conceptual model were confirmed. Based on empirical findings from this study, the implications and suggestions are presented and discussed in this paper.

Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2015-10-26T16:05:56Z No. of bitstreams: 1 Gabriela Schenkel_.pdf: 3048283 bytes, checksum: cd479115e88afd207554abd627ee1c17 (MD5) / Made available in DSpace on 2015-10-26T16:05:56Z (GMT). No. of bitstreams: 1 Gabriela Schenkel_.pdf: 3048283 bytes, checksum: cd479115e88afd207554abd627ee1c17 (MD5) Previous issue date: 2015-02 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os sistemas fotovoltaicos conectados à rede tem como finalidade a conversão da energia solar em energia elétrica. No Brasil, recentemente foi dado o primeiro passo efetivo com a publicação pela ANEEL da Resolução Normativa n° 482. Esta resolução, publicada em 17 de abril de 2012, possibilita à um consumidor doméstico e comercial possuir um sistema de microgeração de energia (hidráulica, solar, eólica, biomassa ou cogeração qualificada) conectado à rede elétrica e fazer compensação de energia. Neste trabalho foi instalado em caráter experimental, no Laboratório de Energias Renováveis da Unisinos, um sistema fotovoltaico conectado à rede com uso de um modelo de microinversor, e buscou-se por meio desta instalação e do monitoramento, analisar o comportamento elétrico e energético do sistema. O sistema é composto por um módulo monocristalino LG255S1C de 255 Wp conectado a um microinversor ENPHASE M215 de 215 W. O período de monitoramento foi de 1° de agosto até 20 de dezembro de 2014. Uma central de aquisição de dados Agilent HP 34970A foi empregada para coletar dados de irradiância no plano do gerador fotovoltaico, corrente e tensão na entrada e saída do microinversor, temperatura de uma célula FV no centro do módulo fotovoltaico e temperatura no dissipador do microinversor. Também foi utilizado como medidor o analisador de energia Fluke 43B, que coleta os dados de potência ativa, potência reativa e potência aparente injetada na rede elétrica pelo sistema. Índices de qualidade de energia como a distorção harmônica total de corrente e fator de deslocamento também foram medidos. A eficiência média diária máxima, considerando a incerteza, medida no microinversor empregado foi de 95,18 % e é semelhante aos valores de eficiência média diária dos microinversores de primeira e segunda geração. O sistema fotovoltaico monitorado com o uso do microinversor atingiu o valor máximo de desempenho global de 0,93. A produção de energia máxima diária em corrente alternada foi de 1,49 kWh. Estima-se, levando em consideração este valor, que a produção mensal pode ser de até 44,7 kWh. Isto significa uma redução de 58 % no consumo de energia em uma residência, levando em consideração o custo de disponibilidade e o sistema instalado em uma residência com consumo médio mensal da região nordeste que é de 120 kWh. / Photovoltaic grid-connected systems aims the conversion of solar energy into electrical energy. In Brazil, was recently given the first effective step with the publication by ANEEL Normative Resolution No. 482. This resolution published on 17 th April, 2012, enables domestic and commercial consumers have an energy microgeneration system (hydro, solar, wind, biomass or qualified cogeneration) connected to mains power and make compensation. In this work was mounted on an experimental character, in the Renewable Energy Laboratory of Unisinos, a photovoltaic grid-connected system that uses a microinverter model, and through this installation and monitoring, analyse the electrical and energetical behavior of the system. The system consists of a 255 Wp LG255S1C monocrystalline module, connected to a 215 W ENPHASE M215 microinverter. The monitoring period was 1 st August to 20 th December, 2014. A central acquisition of Agilent HP 34970A data was used to collect data irradiance in the plane of the PV array, current and voltage at the input and output of microinverter, temperature of a PV cell in the center of the PV module and the microinverter sink. It was also used as a measuring the energy analyzer Fluke 43B, which collects the data of active power, reactive power and apparent power injected into the grid by the system. Power quality indices as the total harmonic current distortion and displacement factor were also measured. The maximum daily average efficiency, considering the uncertainty, measured on the employed microinverter was 95.18 % and is similar than the daily average efficiency values of microinverters of first and second generation. The photovoltaic system monitored using the microinverter peaked overall performance of 0.93. The production maximum daily energy into alternating current was 1.49 kWh. It is estimated taking into account the value that the monthly production can achieved 44.7 kWh. This means a reduction of 58 % in the consumption of a residence considering the availability cost and that the system is installed in a residence with the northest comsumption whose the average monthly consumption is 120.00 kWh.

Thesis. 1976. Ph.D.--Massachusetts Institute of Technology. Dept. of Aeronautics and Astronautics. / Microfiche copy available in Archives and Barker. / Vita. / Includes bibliographical references. / by Roderick A. Hyde. / Ph.D.

Thesis. 1977. M.Arch.--Massachusetts Institute of Technology. Dept. of Architecture. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH. / Bibliography : leaf 92. / by Alva Tabor III. / M.Arch.

Thesis (M.Arch.A.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1978. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH. / Includes bibliographical references. / by Ralph Munroe Lebens. / M.Arch.A.S.