Generering av el med hjälp av solen står idag för en väldigt liten andel av Sveriges totala genereringav el. För att komma upp till en högre nivå krävs inte enorma solcellsparker över hela Sverige, utan tvärtom skulle det kunna gå att använda redan befintliga tak. Det förhållandet är bara ett av flera som påvisar behovet av större kunskapsspridning om dagens energisystem och solcellsteknik. Det finns också ett behov av ökad kunskap om karaktäristiska svenska hus- och taktyper och om vad som är möjligt att göra med varierande slag av solcellsteknik, för att konvertera de olika hustypernas tak till en liten energikälla. Ren solenergi kan inte ensam konkurrera ut fossila bränslen, men det finns god potential för en mycket högre andel av den än vad som är installerat idag. Wallenstam AB är ett energimedvetet fastighetsbolag som bland annat är verksamma i Göteborg. Deras intresse av förnybar energi och av att ersätta fossilt bränsle med mer miljövänlig teknik gav upphov till ett samarbete mellan författaren och Wallenstam AB. Arbetets första del syftar till att inbringa mer och fördjupad kunskap inom ämnet solceller och solcellsanläggningar. Syftet med arbetets andra del är att undersöka vilka möjligheter och hinder det finns med solcellsinstallationer på några olika typiska svenska fastighetstyper. En projektering genomförs på tre olika fastighetstyper i Göteborgsområdet; en industri/kontorslokal, ett modernt flerbostadshus och en fastighet i centrala Göteborg med både bostäder och kommersiell verksamhet. Målet är att utifrån varje fastighets förutsättningar finna den eller de mest lämpade solcellspanelerna för respektive fastighet med avseende på ekonomisk fördelaktighet, estetik samt i vad som är tekniskt möjligt utifrån exempelvis tidigare installerade energisystem. Rapporten och dess resultat är skapat utifrån litteraturstudier, platsbesök på fastigheter, mätningar på ritningar och satellitkartor, beräkningar för hand, samt modellering i PVsyst. Fortlöpande diskussion med personer inom solenergibranschen har också hållits. För att beräkna respektive anläggnings elproduktionskostnad samt för känslighetsanalyser används en webbaserad beräkningsapplikation, tillhörande rapporten El från nya och framtida anläggningar 2014. Huvudresultat är att endast två av de tekniskt möjliga anläggningarna har en elproduktionskostnad som är i närheten av det jämförande elpriset på 0,75 kr/kWh. Det är de polykristallina solcellsanläggningarna på Kvillebäcken 3:1 och Mölnlycke 1:1. Beräkningarna visar på att anläggningarna med polykristallina solcellspaneler på Kvillebäcken 3:1 och Mölnlycke Fabriker 1:1 är riktigt konkurrenskraftiga om kalkylräntan sänks från 4 % till 2 %, eller om investeringskostnaderna minskar med 15 %. På fastigheten Inom Vallgraven 26:8 ligger samtliga elproduktionskostnader över en krona per kilowattimme, men installation av solcellsteknik på en sådan central byggnad skulle kunna ha ett marknadsföringsvärde. / Generation of electricity by use of solar irradiation is today a very small part of the total electricity generation in Sweden. It is not necessary to build a great amount of solar parks all over Sweden to reach a higher level, it could instead be possible by using already existing rooftops. That is one of the situations that indicates the need of a greater knowledge dissemination, about today’s energysystem and the technology of photovoltaics. It also exists a demand of knowledge about characteristic Swedish houses and rooftops. To convert the different kinds of rooftops to small powersources, there is also a demand of knowledge about installations that is possible to do with different kinds of photovoltaics. Although, solar power alone cannot compete with fossil fuels, but it should have a good possibility to reach a much higher level than what exists today. Wallenstam AB is anenergy-conscious company within the real estate business in Gothenburg. Their interests in renewable energy and their ambition to replace fossil fuel with more environment-friendly technology facilitated this cooperation.The first part of the report aims to get more and deeper knowledge about the subject photovoltaics and solar plants. The second part of the report aims to investigate what possibilities and impediments there is with photovoltaic installations at different kinds of typical Swedish houses. A planning work is made at three different types of buildings in the area of Gothenburg. One at an industry/office space, one at a modern apartment block and one at a central building in Gothenburg that has both apartments and commercialized activity. The goal is to find the most suitable photovoltaic installation to each of the three buildings, based on economic advantageousness, appearance and esthetic, and the possibilities with the technology of earlier installed energy systems.The report and the result are formed on the basis of literature studies, site visits at the buildings, measurements at drawings and satellite maps, calculations by hand and modelling in the software PVsyst. Many discussions with people in the solar energy industry were also held. To calculate the Levelized Cost Of Energy (LCOE) and to perform the sensitivity analysis, a web-based calculator was used. The web-based calculator belongs to the report El från nya och framtida anläggningar 2014. The main result shows that only two of the possible photovoltaic installations gets a LCOE that is competitive relative the comparative electricity price at 0,75 SEK/kWh. Installations with polycrystalline solar panels at Kvillebäcken 3:1 and Mölnlycke 1:1. The result also shows that the two installations with polycrystalline solar panels at Kvillebäcken 3:1 and Mölnlycke Fabriker is really competitive if the capital interest rate is reduced from 4 % to 2 %, or if the investment cost isreduced by 15 %. At the property Inom Vallgraven 26:8, the LCOE for all possible installations are over one Swedish krona per kilowatt hour, but an installation with solar panels at a central building like that could have a marketing value. It would also show Wallenstams standpoint for renewable energy, new technology and a sustainable energy system.

Today’s information-centered world leads the ever-increasing consumer demand for more powerful, multifunctional portable devices. Additionally, recent developments on long-lasting energy sources and compliant, flexible systems, have introduced new required features to the portable devices industry. For example, wireless sensor networks are in urgent need of self-sustainable, easy-to-deploy, mobile platforms, wirelessly interconnected and accessible through a cloud computing system. The objective of my doctoral work is to develop integration strategies to effectively fabricate mechanically flexible, energy-independent systems, which could empower sensor networks for a great variety of new exciting applications. The first module, flexible electronics, can be achieved through several techniques and materials. Our main focus is to bring mechanical flexibility to the state-of-the-art high performing silicon-based electronics, with billions of ultra-low power, nano-sized transistors. Therefore, we have developed a low-cost batch fabrication process to transform standard, rigid, mono-crystalline silicon (100) wafer with devices, into a thin (5-20 m), mechanically flexible, optically semi-transparent silicon fabric. Recycling of the remaining wafer is possible, enabling generation of multiple fabrics to ensure lowcost and optimal utilization of the whole substrate. We have shown mono, amorphous and poly-crystalline silicon and silicon dioxide fabrics, featuring industry’s most advanced high-/metal-gate based capacitors and transistors. The second module consists on the development of efficient energy scavenging systems. First, we have identified an innovative and relatively young technology, which can address at the same time two of the main concerns of human kind: water and energy. Microbial fuel cells (MFC) are capable of producing energy out the metabolism of bacteria while treating wastewater. We have developed two micro-liter MFC designs, one with carbon nanotubes (CNT)-based anode and the second with a more sustainable design and easy to implement. Power production ranges from 392 to 100 mW/m3 depending on design. Additionally we have explored a flexible thermoelectric generator (0.139 μW/cm2) and a lithium-ion battery (~800 μAh/m2) for back-up energy generation and storage. Future work includes the implementation of a self-powered System-on-Package which gathers together energy generation, storage and consumption. Additionally we are working to demonstrate Complementary Metal-Oxide-Semiconductor (CMOS) circuitry on our flexible platform, as well as memory systems.

Made available in DSpace on 2015-05-08T14:59:47Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3702525 bytes, checksum: d629112a30790123601bde3a6b3ab9b0 (MD5) Previous issue date: 2013-03-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The emergence of new materials has generated a significant growth for determination with accuracy of your thermophysical properties. The knowledge of these properties for several kinds of materials is essential for any research or engineering project that the heat transfer is relevant, because it´s from these that the rates of heat transfer in a process can be calculated. Method flash is one that stands out most among methods for thermal characterization of materials, in that the front surface of a sample is subjected to an energy pulse of high intensity and short duration, at the same time the temperature of the back surface is measured to determine the thermal diffusivity of the material. This thesis presents a methodology to thermal characterization of semitransparent material using method flash. For this, is made an analysis of the problem of heat transfer with coupling conduction-radiation, where the simultaneous solution of energy equation and the radiative transfer equation (RTE) makes necessary. The finite volume method was used to numerically solve the energy equation and the discrete ordinates method to solve the ETR. A computer code was developed in MATLAB to solve the equations, which is tested and validated with existing cases in the literature. / O crescente aparecimento de novos materiais tem gerado um aumento bastante expressivo na demanda pela determinação com maior exatidão e menor incerteza de medição das suas propriedades termofísicas. O conhecimento destas propriedades para os diversos tipos de materiais é essencial em qualquer pesquisa ou projeto de engenharia onde a transferência de calor tenha relevância, pois é a partir destas que podem ser feitos os cálculos das taxas de transferência de calor presentes num determinado processo. Dentre os métodos utilizados para caracterização térmica dos materiais, o método flash é um dos que mais se destaca. Nele a superfície frontal de uma amostra é submetida a um pulso de energia de alta intensidade e curta duração, sendo o aumento da temperatura na superfície traseira medido e utilizado para determinar a difusividade térmica do material. Neste contexto, o presente trabalho tem como objetivo apresentar uma metodologia para caracterização térmica de materiais semitransparentes através do método flash. Para isso, é feita uma análise do problema da transferência de calor com acoplamento conduçãoradiação, onde uma solução simultânea da equação da energia e da equação da transferência radiativa (ETR) se faz necessária. O método dos volumes finitos foi utilizado para resolver numericamente a equação da energia e o método das ordenadas discretas para resolver a ETR. Um código computacional em MATLAB foi elaborado para resolução das equações obtidas, sendo este testado e validado com casos existentes na literatura.

Le CEA travaille sur des matériaux poreux – alvéolaires, composites, céramiques, etc. – et cherche à optimiser leurs propriétés pour des utilisations spécifiques. Ces matériaux, souvent composés de plusieurs constituants, ont en général une structure complexe avec une taille de pores de quelques dizaines de microns. Ils sont mis en oeuvre dans des systèmes de grande échelle, supérieure à leurs propres échelles caractéristiques, dans lesquels on les considère comme équivalents à des milieux homogènes, sans prendre en compte sa microstructure locale, pour simuler leur comportement dans leur environnement d’utilisation.Nous nous intéressons donc à la caractérisation des propriétés thermiques effectives de matériaux à microstructure hétérogène en cherchant à déterminer par méthode inverse en fonction de la température la diffusivité thermique qu’ils auraient s’ils étaient homogènes.L’identification de la diffusivité de matériaux poreux et/ou semi-transparents est rendue difficile par le couplage conducto-radiatif fort qui peut se développer rapidement dans ces milieux avec une augmentation de la température. Nous avons donc modélisé le transfert de chaleur couplé conducto-radiatif en fonction de la température au sein de matériaux poreux multiconstituants à partir de leur microstructure numérisée en voxels. Notre démarche consiste à nous appuyer sur la microstructure 3D obtenue par tomographie. Ces microstructures servent de support numérique à cette modélisation qui permet d’une part de simuler tout type d’expériences thermiques numériques – en particulier la méthode flash dont les résultats nous permettent de déduire la diffusivité thermique –, et d’autre part de reproduire le comportement thermique de ces échantillons dans leur condition d’utilisation. / The CEA works a great deal with porous materials – carbon composites, ceramics – and aims to optimize their properties for specific uses. These materials can be composed of several constituents and generally has a complex structure with pore size of several tens of micrometers. It is used in large-scale systems that are bigger than its own characteristic scale in which they are considered as equivalent to a homogeneous medium for the simulation of its behavior in its using environment without taking into account its local morphology. We are especially interested in the effective thermal diffusivity of heterogeneous materials that we estimate as a function of temperature with the help of an inverse method by considering they are homogeneous.The identification of the diffusivity of porous and/or semitransparent materials is made difficult because of the strong conducto-radiative coupling can quickly occur when the temperature increases. We have thus modeled the coupled conductive and radiative heat transfer as a function of the temperature within porous multiconstituent materials from their morphology discretized into a set of homogeneous voxels. We have developed a methodology that consists in starting from a 3D-microstructure of the studied materials obtained by tomography. The microstructures constitute the numerical support to this modeling that renders it possible, on the one hand, to simulate any kind of numerical thermal experiments, especially the flash method whose the results render it possible to estimate the thermal diffusivity, and on the other hand, to reproduce the thermal behavior of our materials in their using conditions.

The objective of the diploma thesis is the new building of Cancer Prevention Centre, first of its kind in the Czech Republic. The site is located on steep terrain of the south hillside of Žlutý kopec in Brno, which is a part of Masaryk Oncological Hospital complex. The aim of the Cancer Prevention Centre is to attract the citizens’ attention and invite them to undergo a preventive medical check-up with the potential to save hundreds of lives every year. The project takes this fact in consideration and strives to find ways leading not only towards establishing new relationship between the building and the public, but also towards connecting the city centre and nearby by residential area with the hospital complex. The three volumes of the buildings create a dynamic composition and therefore complete the characteristic development of Masaryk Oncological Centre. The main concept however revolves around the motive of instability, balance and journey which are all linked to tumour diseases.