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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Les freins sociaux à la diffusion des innovations : le cas des panneaux solaires photovoltaïques en France / The social barriers to the diffusion of innovations : the photovoltaic panels market in France

Lecordier-Ferlay, Marianne 25 June 2012 (has links)
Intérêt du sujet : Dans le domaine de la grande consommation, de nombreuses innovations échouent sur le marché européen. L’innovation étant une des variables clé du modèle économique des sociétés occidentales, l’identification des vecteurs de réussite ou d’échec des produits nouveaux est fondamentale pour le succès des entreprises. Parmi les trois groupes de déterminants de l’acceptation des produits nouveaux (les caractéristiques liées à la personne, au produit ou au système social), nous nous intéressons au dernier, jusque là négligé par la littérature.Objectif : Identifier les freins sociaux qui interviennent dans le processus de diffusion d’une innovation.Contribution attendue : Les apports théoriques attendus de ce travail doctoral sont triples :(1) la prise en compte de la théorie des représentations sociales pour la compréhension du comportement d’achat innovateur; (2) la détermination des éléments de la représentation sociale des panneaux solaires photovoltaïques et la mise en évidence d’une potentielle segmentation par la représentation; (3) et l’identification de freins potentiels à l’acceptation de produits nouveaux.Méthode : Deux études ont été menées : tout d’abord une étude de la représentation sociale des panneaux solaires photovoltaïques au travers de deux méthodes (n=97 et n=205) ; puis une étude des motivations à l’achat de panneaux solaires photovoltaïques par les récits de vie(n=16). Principaux résultats : Ce travail doctoral a permis de mettre en évidence trois freins à la diffusion des panneaux solaires photovoltaïques : (1) le changement social induit par l’acceptation de l’innovation; (2) la potentielle multiplicité des représentations sociales et le problème que cela engendre sur la communication interpersonnelle; (3) et le refus d’appartenance au groupe de référence perçu du produit nouveau. / Topic of interest: in the fast moving consumer good, many innovations fail to introduce the European market. Innovation is a key variable in the economic model of Western societies,therefore identifying the success or the failure antecedents is crucial for the company’s success. Among the three groups of antecedents of the acceptance of new products(personal, product and social characteristics), we will focus on the last one, which has been neglected in the diffusion literature.Objective: Understanding the social barriers which intervene in the innovation diffusion process.Contribution expected: The expected theoretical contributions are threefold: (1) introducing the social representation’s theory to understand the innovative consumer behavior; (2)determining the photovoltaic solar panels’ social representation’s association and highlighting a potential segmentation through the social representation; and (3) identifying the potential barriers to innovation acceptance.Method: Two studies were conducted: first, a study on the social representation of photovoltaic solar panels using two methods (n=97 and n=205); then a study on the motivation in installing photovoltaic solar panel using life stories (n=16)Main results: This doctoral work highlight three barriers to photovoltaic solar panels diffusion: (1) the social change induced by the innovation’s acceptance; (2) the potential multiplicity of the social representations and the way it affects the interpersonal communication;
42

Estudo do ganho de energia elétrica em painéis fotovoltaicos usando rastreamento solar baseado em sistemas embarcados. / Study of increase in power generation in photovoltaic solar panels using solar tracking based on embedded systems.

Sérgio Eduardo Alves de Paula 02 July 2015 (has links)
A geração de energia solar fotovoltaica tem crescido anualmente em utilização. Com o aumento dos custos de geração de energia elétrica, fontes renováveis de energia como essa crescem em interesse, até mesmo em aplicações residenciais de microgeração. Este trabalho apresenta o projeto, construção e ensaios de um rastreador solar autônomo, com controle e aquisição de dados de sensoriamento baseado em sistemas embarcados totalmente projetados e produzidos no país, com o objetivo de se aumentar o ganho de energia elétrica gerada a partir de painéis solares de mercado. O projeto do firmware de controle e os algoritmos utilizados foram adaptados continuamente até se atingir os melhores resultados. Foi utilizado um painel solar comum de mercado para realizar os testes, e as placas de circuito impresso projetadas foram confeccionadas localmente. A tomada de dados em diferentes ensaios mostrou que o rastreamento solar de fato aumentou o ganho de energia elétrica com um painel solar comum de mercado, mesmo com alguns problemas a serem corrigidos em uma próxima pesquisa. Assim, a pesquisa realizada confirmou o ganho de energia elétrica para o painel solar escolhido. / Photovoltaic solar generators have grown annually in use. With the increase in electricity generation costs, renewable sources of energy like that grow in interest, even in residential microgeneration applications. This work presents the design, construction and testing of a standalone solar tracker, with control and acquisition of sensors data based on embedded systems totally designed and produced in the country, aiming to increase the power generated from retail solar panels. The firmware design and used algorithms have been continuously adapted to achieve the best results. It was used a standard solar panel to perform the tests, and the designed printed circuit boards were manufactured locally. The data taken in different tests showed that the solar tracking actually increased the power generated with a standard solar panel, even with some problems in the design that have to be corrected in a future implementation. So the project was validated and can be used, including microgeneration in ordinary houses.
43

Projeto de carga eletrônica para caracterização de painéis fotovoltaicos. / Design of an electronic load for photovoltaic module characterization.

Moreno Addad Hassem 19 May 2015 (has links)
A geração solar fotovoltaica em painéis de silício tem se destacado como uma maneira limpa e renovável de atender à demanda por energia elétrica. Este trabalho apresenta o projeto, construção e testes de um sistema autônomo para obtenção da curva IV e caracterização de painéis fotovoltaicos comerciais instalados em campo. Após um estudo do problema de medição de painéis solares, uma especificação da Solução foi concebida. Com base na especificação, foram realizados o projeto elétrico, a construção de protótipos, a escrita do software de medição e os testes de validação em laboratório. Para validação definitiva do hardware desenvolvido, foram realizados testes em campo utilizando um painel solar comercial. Após a tomada de dados e análise dos resultados, conclui-se que o dispositivo concebido atende aos requisitos especificados e cumpre sua proposta inicial. A metodologia empregada neste trabalho pode ser utilizada para geração de outros instrumentos com finalidade similar ou idêntica. / Photovoltaic solar generators, using silicon panels, have grown popular as a clean and renewable way to supply electrical energy. This work presents the project, construction and testing of an autonomous system for IV curve tracing and characterization of commercial photovoltaic panels deployed in the field. After a study how to properly measure solar panels, a Solution was put in a form of a specification. From specifications, the following phases took place: electrical project, prototype construction, software development and lab testing. To perform final validation of the developed hardware, a field test with a commercial solar panel was performed. After collecting and analyzing data from, it was concluded that the design fulfills the required specifications and intended goals. The methodology employed in this work and be utilized to generate other measuring instruments with similar or identical function.
44

Proyecto de negocio sobre estuche para laptop con cargador portatil solar

Chumacero Casallo, Rodrigo Segundo, Correa Aquije, Vilma Paola, Criollo Diaz, Luis Felipe, Julca Zevallos, Sandra, Palomino Castillo, Miguel Antonio 17 July 2021 (has links)
Existen necesidades en las personas, relacionados por un lado a proteger sus portátiles de la mejor manera mientras se trasladan de un lugar a otro, y, por otro lado, la posibilidad de alimentar de energía a sus portátiles en cualquier lugar. Del mismo modo, está identificada la necesidad para cada persona de contribuir con la preservación del medio ambiente dejando de usar o reemplazando muchos productos cotidianos contaminantes por otros con menor o nulo grado de contaminación. Con el presente proyecto se ha logrado conocer las frustraciones que se tiene al no poder tener un producto que satisficiera las necesidades antes señaladas a través del uso del método de exploración y la técnica del periodista; lo que dio como resultado un manifiesto interés por adquirir un producto con las características de Loadtop, es así, que hemos decidido perseverar en nuestra propuesta de valor y en la forma en cómo brindamos el producto. / There are needs in people, related, on the one hand, to protecting their laptops in the best way while they move from one place to another, and, on the other hand, the possibility of supplying power to their laptops anywhere. In the same way, the need for each person to contribute to the preservation of the environment is identified by ceasing to use or replacing many polluting everyday products with others with less or no degree of contamination. With this project it has been possible to know the frustrations that one has when not being able to have a product that meets the needs mentioned above through the use of the exploration method and the journalist's technique; which resulted in a clear interest in acquiring a product with the characteristics of Loadtop, it is thus, that we have decided to persevere in our value proposition and in the way in which we provide the product. / Trabajo de investigación
45

Optimalizace provozu solárního systému určeného k ohřevu TUV školní jídelny / Optimization of the solar system designed for DHW school canteens heating

Doskočil, Filip January 2016 (has links)
Masters’s thesis describes the use of solar energy for solar thermal systems used for domestic hot water heating. It is about the size of the incident solar radiation on Earth. Distributes various types of solar collectors for water heating. It deals with the monitoring, remote management of this system and the design of optimal control used in this area.
46

Kvantifikace energetických ztrát fototermického systému ohřevu TUV při napájení fotovoltaikou / Quantification of energy loss in photothermic system of hot water supply in photovoltaics

Havlíček, Lukáš January 2014 (has links)
This masters’s thesis is about quantify of energy losses in the solar system for heating of hot water by energy from photovoltaics. During the April in year 2014 will be realized a practical data collection on the real system. Then, based on these measurements, calculations will be performed.
47

Lisování prolisů v austenitickém nerezavějícím plechu / Pressing punches on austenitic stainless sheet

Rudolf, Bronislav January 2012 (has links)
Thesis resolvs proposal punches in the sheet metal for heat transfer solar panels. Shapes of punches are selected – piramidal shape and lengwise shape. It is reviewed their possible production and the selected method of Guérin is described. Sheet metal from austenitic stainless 17 240 is selected for the manufacturing. Forming tool is designed with interchangeable punches and elastic medium for various modifications and comparing shapes of punches. It is used hydraulic press CZR 600 for a experimental production.
48

Optimalizace provozu solárního systému určeného k ohřevu TUV školní jídelny / Optimization of the solar system designed for DHW school canteens heating

Doskočil, Filip January 2016 (has links)
Masters’s thesis describes the use of solar energy for solar thermal systems used for domestic hot water heating. It is about the size of the incident solar radiation on Earth. Distributes various types of solar collectors for water heating. It deals with the monitoring, remote management of this system and the design of optimal control used in this area.
49

Montagekvalité av solcellsinstallationer i Mellansverige : En utvärdering av hållfasthet för installerade solcellsanläggningar

Nyman, Joar January 2020 (has links)
Antal installerade solcellsanläggningar har ökat drastiskt de senaste åren i Sverige, och utsikten för ökad mängd solel i Sverige är mycket god, med prognoser på kraftig tillväxt av installerade solcellsanläggningar de kommande åren. Detta med bakgrund att utvecklingen av solcellspaneler har gjort att priset har sjunkit, samt politiska beslut har gjort det lönsamt att investera i solcellsanläggningar i Sverige. Dessa förutsättningar har lagt grunden för en ny växande bransch, solcellsinstallationer. Risken vid en ny och snabbt växande bransch är att kunskapen inom ämnet för de som är verksamma inom branschen kan vara bristfällig samt oseriösa företag kan lockas av att tjäna snabba pengar på en lukrativ marknad. Efter en omfattande litteraturstudie visades att någon större kvalitésundersökning av solcellsinstallationer i Sverige, med avseende på hållfasthet ej har gjorts tidigare. Detta motiverade att denna undersökning var av hög relevans. Syftet med denna studie var att ta reda på om solcellsanläggningar monteras tillräckligt hållfast i Gävle-Dalaregionen med avseende på snö- och vindlast. Fjorton anläggningar har besökts för att samla in data. Data har sedan utvärderats i tre kategorier per anläggning. För att en anläggning skall bedömas som en godkänd skall alla dessa tre kategorier vara godkända. Bedömningen av solcellsanläggningarna gjordes i de tre kategorierna: 1. montagesystemets antal infästningar, 2. mått mellan infästningarna, 3. placering av solcellspanelerna i förhållande till montagesystemet. Resultatet visade att ingen av dessa anläggningar var godkända i samtliga tre kategorier. Vissa anläggningar var godkända i två av tre kategorier, medan två anläggningar var ej godkänd i någon kategori. Vid en summering av bedömningsresultatet för alla anläggningar i de tre montagekategorierna, visades att ca 20% ej gick att fastställa (pga. bristande information) ca 40% var godkända och ca 40% var ej godkända. Bedömningar har gjorts utifrån beräkningsprogram och anvisningar tillhandahållna av tillverkarna av de montagesystem och solcellspaneler som har använts i anläggningarna. Att ingen anläggning var godkänd i samtliga tre kategorier som undersöktes indikerar att solcellsmontage på tegeltak byggs ej tillräckligt hållfast i Gävle-Dalaregionen. Detta kan dock inte generaliseras för solcellsanläggningar på tegeltak i hela Sverige då mängden undersökta anläggningar var relativt liten och endast fördelade på två län i landet. Då det antas att installatörer avser att bygga korrekta anläggningar visar denna studie att kunskap om solcellsmontage med avseende på hållfasthet är bristfällig. Detta kan vara en följd av den stora efterfrågan på solcellsinstallationer, som kan medföra att stort fokus ligger på att installera anläggningar snabbt, och inhämtning av kunskap ej blir prioriterat. / The number of installed PV-systems (Photovoltaic systems) has increased rapidly in Sweden the last years, and the forecast for even more installations shows an increase for the coming years. Due to the price for PV-panels har dropped and political decisions for subventions of PV-systems has made it more profitable to invest in PV-installations in Sweden. These reasons have paved the road for a new growing branch, PV-installations. The risk of a new profitable, fast growing branch is that there might be short of knowledge for new installers, and the possibility that dishonest companies just want to take the advantage of the situation to make quick money, which can lead to installations poorly made.   After a search of published literature in strength of mounting for PV-panels there the result was that this is a rather unexplored subject, which motivated this investigation.   The aim of this study was to find out if PV-panels on tiled roofs were installed correct due to the snow load and wind load in the region Dalarna and Gävleborg in Sweden.   Fourteen PV-systems has been studied and evaluated. When the evaluation of the PV-systems were made the following criteria were considered: number of fixing attached to the roof of the mounting, distance between mounting fixings and how the PV-panels were installed relative the construction of the mounting. A PV-system had to be installed correctly for all three criterias to be considered approved. The result of this work shows that none of the evaluated systems were installed correctly. Some systems were approved in two of the criteria, while two systems were not approved in any of the criteria. The evaluation was made due to calculation programs and instructions from the manufacturers of mounting and PV-panels.   The fact that none of the PV-systems were approved for all three criteria implies that the installations of PV-systems are not made strong enough. This result is not stated for all installations in Sweden because the number of studied PV-systems were not big enough, and the area of the studied installations were rather small. Basis of snow load and wind load variates quite much in Sweden depending on region. It is assumed that designers and constructors attempt to install PV-systems correct, therefor shows this work that there’s a lack of knowledge for construct installations strong enough. This may be a result of the fast increase of PV-installations, where the priority lays in installing many PV-systems, not in education and search of knowledge.
50

Sustainability Assessment of a Battery Storage System : Case study of a building-applied photovoltaic system

Flygare, Klara, Frykholm, Selma, Tingstedt, Moa January 2022 (has links)
This bachelor thesis assesses the environmental sustainability of the implementation of a battery storage system in a commercial building. The thesis compares  two case studies, Case 1 being a commercial building with installed solar panels and Case 2 being a commercial building with installed solar panels and a battery storage system. Based on simulations the thesis investigates a battery storage system’s impact on sustainability in terms of CO2 emission equivalents and nuclear wastes. The study is applied in the geographical region of northern Stockholm. The models and calculations are conducted  in MATLAB, Excel and Google Sheets. The effects of the implementation depends on the electricity mix. Implementation of a battery storage system in a commercial building with solar panels, supplied with the Swedish electricity mix, increased the CO2 emissions with 3.6986 ⋅ 103 kg. A majority of the increased emissions was caused by the solar panels. They increased the CO2 emissions with 3.3876 ⋅ 103 kg in Case 1 and 3.6988 ⋅ 103 kg in Case 2. The nuclear waste was reduced with 878.3 g in Case 1 and 959 g in Case 2. The results also showed an increased consumption of renewable energy and a decreased load on the grid due to the implementation of a battery storage. For the sensitivity analysis the Swedish electricity mix was replaced by the European Union electricity mix. The resultant conclusion is that a commercial building decreased its CO2 emissions when solar panels were installed and a battery storage system implemented. The overall conclusion is that the environmental sustainability examination of the implementation resulted in an increasing emission of CO2 and a decreased amount of nuclear waste. Sustainable benefits such as an increased consumption of renewable energy of the building, a reduced dependence on the grid and improved conditions for phasing out nuclear power were also retrieved from the results. On a larger scale it has been made clear that battery storage systems are much needed in the conversion to renewable energy sources, and that research and investment in solar power and storage systems are of utter importance.

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