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Mapeamento e priorização de fontes de geração distribuída como suporte ao novo planejamento da distribuição / Mapping and prioritization of distributed generation sources as support to the new distribution planningAzzolin, Herton Naressi 16 March 2015 (has links)
Despite the growing movement of the share of renewable sources in the global energy matrix, the weight of sources such as natural gas, coal and petroleum derivatives is considerably significant. In this respect, the need for diversification of the energy matrix is evident and urgent, mainly due to the growing demand for energy, and requires appropriate planning of the matrix transition process in order to attend the growing demand on a sustainable basis and in a balanced way. Being the Distributed Generation (DG) a viable and real alternative to contribute to this scenario favorably, beyond the amount of intrinsic variables to DG that can impact positively or negatively on the electrical system, the development of methods and tools to support the usual techniques of planning need to be reviewed. In this sense, it is proposed in this study a methodology for mapping and prioritizing of DG sources from renewable resources, to support the new perspective of distribution planning. The focus is given to the wind power, photovoltaic, hydro and biomass, dealt in the current literature as the most promising for diversification of energy sources. The methodology includes the realization of a mapping of available energy resources in an enclosed area for study, indicating the most favorable places of exploitation. Documents already established concerning energy potential, such as atlas and energy balances, are used as reference information for the mapping. Once mapped the resources available, it is estimated the energy capacity that they represent, through methods and equations which consider the main variables to estimate the potential of each source. The methodology also includes a step of prioritization of mapped sources from multiple quantitative and qualitative criteria, to indicate the best form of participation of them in two different perspectives of analysis. The first one under the point of view of electric utilities, with the focus on the potential use to support the system expansion and operation, and the second one from the perspective of investors, aimed at exploitation the potential for expansion of its generation mix. For the multi-criteria approach of prioritizing the sources it is used the Analytic Hierarchy Process (AHP) method. The modeling is applied as a case study from the area of operation of a electric utility in the state of Rio Grande do Sul. / Apesar do movimento crescente da participação de renováveis na matriz energética global, o peso de fontes como gás natural, carvão e derivados do petróleo é consideravelmente significativo. Neste aspecto, a necessidade de diversificação da matriz elétrica é notória e urgente, principalmente pela demanda crescente por energia, e requer um planejamento adequado do processo de transição da matriz, de modo a atender o crescimento de demanda em bases sustentáveis e de forma equilibrada. Sendo a Geração Distribuída (GD) uma alternativa viável e concreta para contribuir favoravelmente com esse cenário, e ainda, considerando a quantidade de variáveis intrínsecas à GD que podem impactar positiva ou negativamente no sistema elétrico, o desenvolvimento de métodos e ferramentas para suporte às técnicas usuais de planejamento precisam ser revistos. Neste sentido, propõe-se nesse estudo uma metodologia para mapeamento e priorização de fontes de GD a partir de recursos renováveis para suporte à nova ótica de planejar a distribuição. O foco é dado para as fontes eólica, fotovoltaica, hídrica e biomassa, abordadas na literatura atual como as mais promissoras para diversificação da matriz energética. A metodologia contempla a realização de um mapeamento dos recursos energéticos disponíveis em uma área delimitada para estudo, indicando os pontos mais favoráveis de aproveitamento. Utilizam-se como referências de informações para o mapeamento, documentos já consolidados relativos ao potencial energético, tais como, atlas e balanços energéticos. Uma vez mapeado os recursos disponíveis, estima-se a capacidade energética que os mesmos representam, através de métodos e equacionamentos que consideram as variáveis principais de estimação do potencial de cada fonte. A metodologia contempla ainda a etapa de priorização das fontes mapeadas, a partir de múltiplos critérios de ordem quantitativa e qualitativa, de modo a indicar a melhor forma de participação das fontes em duas perspectivas distintas de análise. A primeira sob o ponto de vista da distribuidora, com o foco no aproveitamento do potencial para suporte à expansão e operação do sistema, e a segunda sob a ótica dos investidores, voltada para o aproveitamento do potencial para expansão do seu mix de geração. Para a abordagem multicritério de priorização das fontes utiliza-se o método Analytic Hierarchy Process (AHP). A modelagem é aplicada a partir de um estudo de caso desenvolvido na área de atuação de uma distribuidora de energia do estado do Rio Grande do Sul.
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Essays on issues in climate change policyDaube, Marc January 2017 (has links)
This thesis addresses three themes relating to climate change. The first is which types of fossil fuel to leave in the ground when they can differ in both their extraction cost and emissions rate. The analysis shows that without resource constraints there will always be use of at least one fossil fuel in the steady-state. With exhaustion constraints, any fossil fuel that has a lower extraction cost than the marginal cost of the backstop will be extracted in finite time regardless of the emissions rate. The only environmental consideration is the timing of extraction rather than leaving fossil fuel stock in the ground forever. The second theme is how altruistic concern of individuals for the well-being of others influences the socially optimal consumption levels and optimal emissions tax in a global context. If individuals have altruistic concern but believe that their consumption is negligible, they will not change their behaviour. However, non-cooperative governments maximising domestic welfare will internalise some of the damage inflicted on other countries depending on the level of altruistic concern individuals have and the cooperative optimum also changes as altruism leads individuals to effectively experience damage in other countries as well as the direct damage to them. Still, for behaviour to change, individuals need to make their decisions in a different way. The third chapter develops a new theory of moral behaviour whereby individuals balance the cost of not acting in their own self-interest against the hypothetical moral value of adopting a Kantian form of behaviour, asking what would happen if everyone else acted in the same way as they did. If individuals behave this way, then altruism matters and it may induce individuals to cut back their consumption. But nevertheless the optimal environmental tax is exactly the same as the standard Pigovian tax.
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Státní podpora a zdanění obnovitelných zdrojů / State Aid and Taxation of Renewable ResourcesKouba, Matěj January 2011 (has links)
The thesis with the topic State Aid and Taxation of Renewable Resources deals with the renewable resources in general, reason of their support, function of renewable resources powerplants etc. This thesis describes also the state aid of renewable resources in the Czech Republic and their taxation as well. A small part of this thesis analyzes the state aid in the other EU countires and contains their comparision with the Czech Republic.
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Ekonomika rychle rostoucích dřevin / Economy of fast-growing woody speciesLevý, Lukáš January 2011 (has links)
The thesis is focused on analyzing and evaluation of importance and potential of fast-growing woody species for specifics of Czech economy and local conditions. Thesis will inquire into applicability of each fast-growing species for Czech natural conditions. Further I will investigate opportunities of subvention from public authorities. Next part of thesis will be focused on all activities and processes during cultivation of fast-growing species from acquiring land to processing of wooden mass. For each activity will quantify costs of labor and physical capital during cultivation of fast-growing woody species for different subjects in Czech economy, like household owning a soil or company with unused outside areas. Thesis will be comparing possible energetic savings of profits for a number of alternatives with different energy prices development in ongoing years. Practical output of this thesis should not be only the compilation of all these information into one text, but above all also a complex formula which everyone can use for the calculation of his opportunities for cultivating of fast-growing woody species.
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Ocenenie fotovoltaickej elektrárne / Evaluation of a Photovoltaic Power PlantHrubjáková, Martina January 2011 (has links)
The aim of this master's thesis is the evaluation of a company, of which the purpose of its existence is the development and running of a photovoltaic power plant. The estimated value refers to December 31st, 2011 and is determined for the purpose of potential sale of the company. The thesis consists of theoretical part, which includes determination of basic terms and concept of the evaluation process, and the practical application of theoretical knowledge on the specific company. A brief presentation of the company is followed by the strategic analysis, which identifies the most important opportunities and threats for the company in the future. Together with a review of previous company's financial results it represents the initial point for the preparation of a financial plan. The final part of the thesis includes the evaluation of the company in two versions. The first one is based on the assumption of termination company's activity after a specific period. The second one is based on the going-concern principle. The statement about the value of the company is supplemented by the valuation of the investment project.
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Razvoj postupaka sinteze polimernih mreža i hibridnih materijala / Development of methods for polymer networks and hybrid materials synthesisRistić Ivan 27 May 2011 (has links)
<p>U ovom radu vršena su istraživanja u cilju razvoja novih postupaka sinteze za nekoliko vrsta polimernih mreža i hibridnih biopolimernih materijala za specijalne primene. Cilj je bio da se razvije novi postupak sinteze rotaksana na bazi poli(etilen glikola) i β-ciklodekstrina kaoprekursora mreža. Dobijeni prekursori mreža iskorišćeni su za sintezu topoloških gelova koji su umreženi preko hidroksilnih grupa ciklodekstrinskih prstena. Analiziran je i uticaj količine umreživača, odnosno gustine umreženja, na svojstva bubrenja. Proučavan je i uticaj nanopunila na svojstva modelnih epoksi mreža na bazi bisfenola A i poli(oksi propilen) diamina. Kao punila korišćene su nanočestice nemodifikovanog i površinski modifikovanog titanijum(IV)oksida (TiO<sub>2</sub>). Dinamičko-mehaničkom analizom potvrđen je ojačavajući efekat punila. Razvijen je postupak sinteze poli(D,L-laktida) u mikrotalasnom polju, čime je drastično smanjeno vreme polimerizacije (sa 150 sati na 15 minuta) u odnosu na klasičnu termosintezu. Sintezom poli(laktida) kao i kopolimera poli(laktida) sa biorazgradivim monomerima (na osnovu obnovljivih sirovina) dobijeni su materijali izuzetnih ekoloških svojstava. Poli(laktid) se odlikuje veoma dobrim mehaničkim svojstvima i biorazgradivošću, dok je blok-kopolimerizacijom sa drugim biorazgradivim monomerima vršena sinteza termoplastičnih poliestara. Variranje dužine segmenata je ostvareno sintezom adekvatnih oligomera kao prekursora za kopolimerizaciju. Vršeno je projektovanje sirovinskog sastava segmentiranih elastomera kod kojih postojanje mekih i tvrdih segmenata ima za posledicu mikrofaznu separaciju faza što u toku eksploatacije utiče na mehanička svojstva i mogućnost III razgradnje. Na taj način dobijeni su elastomerni materijali željenih svojstava. Metodama FTIC i 1H NMR spektroskopijom potvrđena je pretpostavljena struktura segmenata i finalnih termoplastičnih poliestara. Analizom molskih masa poliestara metodama gel propusne hromatografije, viskozimetrije i osmometrije napona pare, potvrđena je izuzetna kontrola reakcija polimerizacije i uspešnost primenjenih metoda sinteze. Analiza toplotnih svojstava blok poliestara diferencijalno skenirajućom kalorimetrijom je pokazala da zbog nemešljivosti faza, tvrdih i mekih segmenata, finalni blok poliestri mogu da pokažu razlike u temperaturama faznih transformacija u zavisnosti od dužine i udela segmenata. Termogravimetrijskom analizom je potvrđen uticaj dužine segmenata i faznog razdvajanja na toplotna svojstva termoplastičnih poliestara. Očekuje se da će sintetisani materijali biti podesni za primene u inženjerstvu tkiva, a posebno kao materijali za kontrolisano otpuštanje lekova.</p> / <p>The primary goal of the work described in this thesis was to develop new methods for the<br />synthesis of polymer networks and hybrid biopolymers for special applications. The purpose was a development of synthesis procedure for the preparation of rotaxane based on poly(ethylene glycol) and β-cyclodextrin, as network precursors. These network precursors were then cross-linked through hydroxy groups on cyclodextrine rings. Polyrotaxanes are intermediary products in the synthesis of topological gels and they are formed by the insertion of the linear polymer chains of poly(ethylene oxide) into the β-CD cavities. In this work polyrotaxanes from acetylated-β-CD and poly(ethylene oxide) were synthesized. The influence of crosslinker contents, and crosslink density on swelling properties was investigated. The influence of synthesis parameters and filler modification on reactions and final properties of organic-inorganic hybrid materials based on epoxy resin and an organically modified titanium(IV)oxide (TiO2) was investigated. Dynamic-mechanical analysis was used to determine reinforcement effect of nanofiller on the epoxy resin properties. The aim of this work was the investigation of microwave irradiation on the polymerization of D,L-lactide. It was found that if heating is carried out in the microwave field polymerization time of D,Llactide rapidly decreases from 150 hours to 15 minutes. Environmentally friendly materials were obtained from poly(lactide) and copolymers of poly(lactide) and monomers based on renewable resources. Poly(lactide) is biocompatible and biodegradable polymer with high stretching and low extension capacities. It has been used for the production of orthopedic fraction fixators and sutures surgery. Poly(lactide) was used for thermoplastic polyester (TPE) synthesis. Most thermoplastic polyesters derive their properties from segmented or block structures which are achieved by alternating hard and soft segments. FT-IR and 1H NMR spectroscopy were confirmed the assumed structure of segments and final thermoplastic polyesters. Since the properties of these materials strongly depend on the degree of phase separation, the influence of the lenghts of soft and hard segment on final properties of obtained TPEs was studied. Analysis of molecular mass of these polyesters by gel permeation chromatography, vapor pressure osmometry and viscozimetric analysis confirmed that good control of polymerization was achieved and that synthesis methods were successful. Thermal properties were characterized by means of differential scanning calorimetry (DSC) and thermo-gravimetric analysis (TGA). Phase separation had strong influences on thermal properties of obtained TPEs. DCS measurements showed that due to poor mixability of hard and soft segments, final block polyesters could have different temperatures of phase transitions depending on the length of the segments. Thermal degradation and the influence of phase separation on thermal stability of segmented thermoplastic polyesters were confirmed by nonisothermal analysis, using thermogravimetric analysis. It is expected that synthesized materials will be suitable for tissue engineering and as drug carriers.</p>
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Analýza vlivu tepelných jevů na termofotovoltaický systém / Analysis of the influence of thermal effects on thermophotovoltaic systemKolář, Jakub January 2014 (has links)
This semestral thesis focuses on the description of specific renewable resources in the form of thermophotovoltaic cells using selective radiators with micro/nano structures. This work deals with an introduction of renewable resources and specifically focuses on thermophotovoltaic. Thesis describes basic principles, but also influences affecting the proper functioning of these systems. It also focuses on selective radiators, which are created by mikro/nano structures, and factors that can affect their implementation or simulation. Part of the work are also examples of calculations of basic parameters of the structures, which will be used in the simulations. Next chapters are dealing with simulations which are analyzing thermal effects on termophotovoltaic system. Except the analysis itself there is also partial optimalization solving some of the negative thermal effects.
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Podzemní pneumatický akumulátor energie / The underground pneumatic energy storagePochylý, Jiří January 2014 (has links)
This diploma thesis deals with the underground compressed air enery storage. Thesis can be divided into several parts. The first part focuses on the theoretical analysis which decribes reason of renewable resources implementation to the electric grid and how renewable resources affect electric grid. Second part describes compression and expansion stage. Last part deals with design of storage facility which is suitable for different energy supplies. Extracted coal mines of Rosicko-Oslavany area is used as suitable underground storage.
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Obnovitelné zdroje energie jako námět pro fyzikální experimenty / Renewable Energy Sources as Inspiration for Physics ExperimentsKopřiva, Tomáš January 2018 (has links)
Title: Renewable Energy Sources as Inspiration for Physics Experiments Author: Bc. Tomáš Kopřiva Department: Department of Physics Education Supervisor: RNDr. Petr Kácovský, Ph.D. Abstrakt: This thesis deals with a current issue of renewable resources of energy. It focuses on the Sun, wind and hydrogen as energy resources.The first part of the thesis provides a theoretical explanation to these resources and is followed by a practical part with the aim to explain this issue to students by using experiments included in worksheets. The theoretical part is focused on the minimal knowledge that is needed for completing the worksheets. This part also describes suitability of these resources in the context of the Czech Republic. The second part of the thesis is exclusively experimental. It describes educational kits that can be used to demonstrate renewable resources of energy. It also includes instructions to create worksheets. The attachment, which is part of the thesis, contains a set of worksheets and a CD which, among others, contains other worksheets filled in by students. Key words: renewable resources, worksheet, experiment, solar cell, fuel cell, wind turbine, efficiency
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Thiol−ene Coupling of Renewable Monomers : at the forefront of bio-based polymeric materialsClaudino, Mauro January 2011 (has links)
Plant derived oils bear intrinsic double-bond functionality that can be utilized directly for the thiol–ene reaction. Although terminal unsaturations are far more reactive than internal ones, studies on the reversible addition of thiyl radicals to 1,2-disubstituted alkenes show that this is an important reaction. To investigate the thiol–ene coupling reaction involving these enes, stoichiometric mixtures of a trifunctional propionate thiol with monounsaturated fatty acid methyl esters (methyl oleate or methyl elaidate) supplemented with 2.0 wt.% Irgacure 184 were subjected to 365-nm UV-irradiation and the chemical changes monitored. Continuous (RT– FTIR) and discontinuous (NMR and FT–Raman) techniques were used to follow the progress of the reaction and reveal details of the products formed. Experimental results supported by numerical kinetic simulations of the system confirm the reaction mechanism showing a very fast cis/trans-isomerization of the alkene monomers (<1.0 min) when compared to the total disappearance of double-bonds, indicating that the rate-limiting step controlling the overall reaction is the hydrogen transfer from the thiol involved in the formation of final product. The loss of total unsaturations equals thiol consumption throughout the entire reaction; although product formation is strongly favoured directly from the trans-ene. This indicates that initial cis/trans-isomer structures affect the kinetics. High thiol–ene conversions could be easily obtained at reasonable rates without major influence of side-reactions demonstrating the suitability of this reaction for network forming purposes from 1,2-disubstituted alkenes. To further illustrate the validity of this concept in the formation of cross-linked thiol–ene films a series of globalide/caprolactone based copolyesters differing in degree of unsaturations along the backbone were photopolymerized in the melt with the same trithiol giving amorphous elastomeric materials with different thermal and viscoelastic properties. High thiol–ene conversions (>80%) were easily attained for all cases at reasonable reaction rates, while maintaining the cure behaviour and independent of functionality. Parallel chain-growth ene homopolymerization was considered negligible when compared with the main coupling route. However, the comonomer feed ratio had impact on the thermoset properties with high ene-density copolymers giving networks with higher glass transition temperature values (Tg) and a narrower distribution of cross-links than films with lower ene composition. The thiol–ene systems evaluated in this study serve as model example for the sustainable use of naturally-occurring 1,2-disubstituted alkenes at making semi-synthetic polymeric materials in high conversions with a range of properties in an environment-friendly way. / Vegetabiliska oljor som innehåller dubbelbindningar kan användas direkt för thiolene reaktioner. Trots att terminala dubbelbindningar är mycket mer reaktiva än interna visar dessa studier att den reversibla additionen av thiyl radikaler till 1,2-disubstituerade alkener är en viktig reaktion. För att undersöka tiol–ene reaktionerna, som ivolverar dessa alkener förbereddes stökiometriska blandningar av en trifunktionell propionat tiol och enkelomättade fettsyrametylestrar (metyloleat eller metyl elaidat) samt 2.0 vikt.% Irgacure 184. Dessa blandningar utsattes för 365-nm UV strålning och de kemiska förändringarna studerades. De kemiska förändringarna analyserades med olika kemiska analysmetoder; realtid RT–FTIR, NMR och FT–Raman. Dessa användes för att analysera de kemiska reaktionerna i realtid och följa bildandet av produkterna. Reaktionsmekanismen bekräftades med hjälp av experimentella data och beräkningar av numeriska och kinetiska simuleringar för systemet. Resultaten visar en mycket snabb cis/trans-isomerisering av alkenmonomeren (<1.0 min) jämfört med den totala förbrukningen av dubbelbindningarna, vilket indikerar att det hastighetsbegränsande steget kontrolleras av väteförflyttningen från tiolen till slutprodukten. Förbrukningen av den totala omättade kolkedjan är lika med tiolförbrukningen under hela reaktionen, även om bildandet av produkten gynnas från trans-enen. Detta indikerar att den första cis/trans-isomerstrukturen påverkar kinetiken. Höga tiol-ene utbyten kan enkelt erhållas relativt snabbt utan inverkan av sidoreaktioner. Detta innebär att denna reaktion kan användas som nätverksbildande reaktion för flerfunktionella 1,2-disubstituted alkenmonomerer. Vidare användes fotopolymerisation i smälta på en serie globalid/kaprolaktonbaserade sampolyestrar med varierad grad av omättnad med samma tritiol vilket resulterade i bildandet av amorfa elastomeriska material med olika termiska och viskoelastiska egenskaper. Hög omsättning (>80%) uppnåddes relativt enkelt för samtliga blandningar oberoende av den initiala funktionaliteten. Homopolymerisation av alkenen var försumbar i jämförelse med den tiol–en-reaktionen. Mängden alkengrupper har inverkan på härdplastsegenskaperna där en hög andel alken ger en nätstruktur med högre glastransitionstemperatur (Tg). Tiol–ene reaktionen utvärderades i modellsystem baserade på naturlig förekommande 1,2-disubstituterade alkener för att demonstrera konceptet med tiol-förnätade halvsyntetiska material. / QC 20110915
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