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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.
1

Stanovení lipofility léčiv pomocí HPLC / Determination of Lipophilicity of Drugs by HPLC

Pleváková, Magdaléna January 2015 (has links)
3 ABSTRACT Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of biophysics and physical chemistry Author: Magdaléna Pleváková Supervisor: Ing. Vladimír Kubíček, CSc. Thesis title: Determination of Lipophilicity of Drugs by HPLC In this thesis a RP-HPLC method for fast and reliable determination of lipophilicity was proposed and tested. Stationary phase was selected by using hydrophobic substraction model. Capacity factors of the chosen substances were initially measured on Zorbax ECLIPSE XDB C18 250x4,6 mm, 5µm column, which exhibits almost identical retention characteristics as the column used for this purpose until now. Then the capacity factors of the same substances were determined by using Zorbax ECLIPSE XDB-C18 50x4,6 mm, 1,8µm column that was selected to reduce retention times significantly. A group of newly synthesised drugs based on structure of pyrazine served as samples for the measurement. The reproducibility of the capacity factor values determined using both columns was compared and the independence of the capacity factor on the mobile phase flow was confirmed. The capacity factors of two homologous series and a group of benzimidazols were consequently determined on Zorbax ECLIPSE XDB-C18 50x4,6 mm, 1,8µm column using various compositions of mobile phases. Several...
2

A description of the electricity system in Spain since 2005 and the economic potential for renewable energy technologies

Izquierdo-Millan, Javier 24 January 2014 (has links)
The energy system in Spain can be characterized as being high energy intensive when compared to the rest of Europe and because of its high dependence on imported resources (around 84%). The focus of this document is to explore a novel approach to describe, as part of this energy system, the electricity system in Spain since 2005 and the economic potential for renewable energy technologies (RET) to replace the electricity generated from fossil resources by 2050. The heart of the design and implementation of any RET policy should be the reduction or elimination of fossil fuel dependency. This document aims at describing the evolution of the Spanish electricity system in the last decade, and addressing the possible influence of certain factors in the design and implementation of the electricity system by using modern modeling technologies to evaluate the potential of RET. This will represent a novel approach to bridge the results from modeling technologies to policy makers. To ensure the credibility and reliability of the data researched, validation criteria has been used which includes the accuracy of information, the content (whether factual or opinion), time (limited to certain periods), format (validity of internet sources, journals, etc), authority (reputable authors and sources), objective reasoning, currency and links to other resources, and the quality of writings and its review among others. The proposed research approach follows a methodology where the first step is to understand the electricity system in Spain, followed by the definition of the model of interest (optimization models) and the design of three different scenarios (Business as Usual, FIT and High fossil prices) for the evaluation of the potential of RET, finishing with the analysis of the results from the model and data collected from the perspectives of what has been done in previous RET policies and plans, and the possible influence of factors such as organizations and corporations on those policies and plans. The results obtained from the model are analysed and compared to the Business as Usual scenario. The amount of electricity generated from fossil resources and to be replaced by RET is calculated using the scenarios, as well as the evolution of primary energy, imports, final energy consumptions and CO2 emissions. In order to test the applicability of this approach, the results of the model have been compared with the current situation of the Spanish electricity system. Calculations using capacity factors of the RET and their share in the current electricity generation are performed in order to identify the final amount of power (MW) to be installed in order to replace the electricity generated (GWh) by fossil resources by 2050. Based on the conclusions, RET has the potential to replace the generation of electricity from fossil fuels but improvements in the efficiency of RET will be needed. In addition, it is recommended that significant considerations in RET policy like the energy and electricity systems should be a strategic component of the Spanish policy system, be done in order to set the Spanish electricity system in a more sustainable path .
3

The Interdependence of Energy and Sustainability

Favero Bolson, Natanael 11 1900 (has links)
The increasing frequency of extreme weather events is a consequence of changing climate. The direct physical causes are carbon dioxide emissions from the intensive use of fossil fuels and accelerated soil and plant decomposition from alterations in land use. Efforts to avoid a global environmental calamity and engineer a shift towards a more sustainable path are at the forefront of global agenda. However, beyond all the commitments and good intentions, there is no consensus on what constitutes sustainability, the requirements for a power transition towards a post-carbon era, or the energy resources available to achieve economic goals. This dissertation aims to clarify the relationship between energy and sustainability. We begin with a review of capacity factors for the leading power technologies at a global and regional scale to understand performance of these technologies and their potential. To address the challenge of evaluating sustainability, we propose a new approach, the eight-dimensional sustainability octagon. This approach broadens the fundamental pillars of sustainability (social, environmental, and economic), and provides a simple yet robust tool for comparing the sustainability of countries on the Earth. This analysis shows that the world is performing at one-third of achievable sustainability levels. Afterwards, we assess current global energy mix from a primary power perspective and estimate energy savings from- and limitations of electrification. We evaluate the power requirements, nominal power to be installed, infrastructure needs, and carbon dioxide emissions associated with replacing current fossil electricity generation mix with renewables. This evaluation indicates that complete decarbonization of the global power mix is impossible by 2050, and electrification could further delay decarbonization. At a single country level (case study), we analyze connections between the ongoing energy-environmental crisis and population growth to assess the feasibility of achieving the government of Rwanda’s developmental goals, given available power resources. We evaluate Lake Kivu in Rwanda as a complex methane source and energy system. We assess the implicit risks and environmental impacts of large-scale methane production to generate electricity. From our analysis, Rwanda is overpopulated, and the available energy resources can only secure low incomes for the population.
4

Metodologia de micrositing para terrenos complexos baseada em CFD com softwares livres de código aberto

Radünz, William Corrêa January 2018 (has links)
Micrositing é o campo do posicionamento estratégico dos aerogeradores na área do parque eólico visando a con guração mais promissora em termos econômicos ou de produção. Dado que em terrenos complexos as características do vento variam na área do parque eólico de forma não-linear, emprega-se a modelagem numérica do vento por CFD para extrapolar os dados medidos para toda a região. O presente trabalho consiste no desenvolvimento de uma metodologia de micrositing em terrenos complexos capaz de auxiliar no projeto do layout e seleção do tipo e altura de eixo do aerogerador que maximiza o fator de capacidade (FC) utilizando softwares livres de código aberto. A metodologia consiste na simulação do vento para várias direções de incidência, assimilação das medições, convers ão de velocidade em densidade de potência, ponderação por frequência de ocorrência de cada direção, sobreposição, seleção das coordenadas dos aerogeradores e cálculo do FC para diversas con gurações de tipo e altura de eixo dos aerogeradores. Veri cação, validação e seleção das constantes do modelo de turbulência é realizada anteriormente às simulações Veri cou-se que o modelo k- produziu um escoamento horizontalmente homog êneo e que o melhor desempenho na validação foi obtido com a escolha de constantes para escoamentos atmosféricos. A metodologia foi demonstrada em uma região de terreno complexo em que o FC do parque eólico proposto apresentou caráter convergente com o re no progressivo da malha, porém oscilatório em termos do número de direções simuladas. Por m, obteve-se FC brutos superiores a 40% para as cinco melhores con gurações e de aproximadamente 52% no melhor caso, indicando bom potencial eólico. A metodologia foi capaz de preencher uma lacuna na literatura cientí ca de micrositing ao possibilitar o planejamento do layout, tipo de aerogerador e altura de eixo, bem como a estimativa da produção e FC brutos da usina em terrenos complexos. Além disso, a estrutura de trabalho com o uso de recursos computacionais livres e de código aberto reforça o caráter de desenvolvimento contínuo, compartilhamento e transparência da metodologia. / Micrositing is the eld concerned with the strategic positioning of wind turbines in the wind farm area aimed at the most promissing con guration economically- or yield-wise. Given the wind characteristics vary non-linearly across the wind farm area in complex terrain, numerical wind modeling with CFD is employed to extrapolate the measured data to the whole site. The present work consists of the development of a micrositing methodology in complex terrain capable of assisting the layout project and selection of wind turbine type and hub height that maximizes the capacity factor (CF) using free and open-source software. The methodology consists of simulating the wind for a number of incoming directions, assimilation of measurements, conversion of wind speed into power density, weighing by frequency of occurrence of each direction, overlapping, selection of wind turbine coordinates and CF calculation for a number of wind turbine types and hub heights. Veri cation, validation and selection of turbulence model constants is performed previous to the simulations It was veri ed that the k- model is able to sustain horizontally-homogeneous ow and that the classic atmospheric ow constants performed best in the validation step. The methodology was demonstrated in a complex terrain region for which the proposed wind farm CF showed converging behavior with progressive mesh re nement, however oscillating with the number of wind directions simulated. Ultimately, CF greater than 40% were obtained with the ve best performing con gurations and approximately 52% in the best case scenario, suggesting good wind potential. The methodology was capable of lling a major gap in the scienti c literature of micrositing for allowing the layout planning, selection of wind turbine type and hub height, as well as gross production estimates and CF for the wind farm in complex terrain. Additionally, the free and open-source-based framework strengthens the continuous development, sharing and transparency of the methodology.
5

On the velocity distribution for hydro-kinetic energy conversion from tidal currents and rivers

Lalander, Emilia, Grabbe, Mårten, Leijon, Mats January 2013 (has links)
Tidal currents and rivers are promising sources of renewable energy given that suitable turbines for kinetic energy conversion are developed. To be economically and technically feasible, a velocity distribution that can give a high degree of utilization (or capacity factor), while the ratio of maximum to rated velocity is low would be preferable. The rated velocity is defined as the velocity at which rated power is achieved. Despite many attempts to estimate the resource, however, reports on the possible degree of utilisation from tidal currents and rivers are scarce. In this paper the velocity distribution from a number of regulated rivers, unregulated rivers and tidal currents have been analysed regarding the degree of utilisation, the fraction of converted energy and the ratio of maximum to rated velocity. Two methods have been used for choosing the rated velocity; one aiming at a high fraction of converted energy and one aiming at a high degree of utilisation. Using the first method, with a rated velocity close to the maximum velocity, it is unlikely that the turbine will reach the cut-out velocity. This results in, on average, a degree of utilisation of 23% for regulated rivers, 19% for unregulated rivers and 17% for tidal currents while converting roughly 30-40% of the kinetic energy. Choosing a rated velocity closer to the mean velocity resulted in, on average, a degree of utilisation of 57% for regulated rivers, 52% for unregulated rivers and 45% for tidal currents. The ratio of maximum to rated velocity would still be no higher than 2.0 for regulated rivers, 1.2 for unregulated rivers and 1.6 for tidal currents. This implies that the velocity distribution of both rivers and tidal currents is promising for kinetic energy conversion. These results, however, do not include weather related effects or extreme velocities such as the 50-year velocity. A velocity factor is introduced to describe what degree of utilisation can be expected at a site. The velocity factor is defined as the ratio U-max/U-rate at the desired degree of utilisation, and serves as an early indicator of the suitability of a site.
6

Geotermi i Ungern : Undersökning av Ungerns energisituation inriktat på geotermi samt kapacitetsfaktorn för det största geotermiska värmeverket i Mellaneuropa.

Hammar, Mikael, Huszág, Máté January 2014 (has links)
Hungary’s share of renewable energy in 2010 was 7.9 %, and their renewable energy goal for 2020 is 14.65 %. Geothermal energy is one option that could help to achieve the goal, since Hungary has favorable bedrock, the temperature gradient is above average and thepermeability is high. Today Hungary is importing just over half of its primary energy supply. Because of political conflicts between nations Hungary wants to expand its own production of energy. One of the major investments implemented was to build the largest geothermal heating plant in central Europe, located in Miskolc. This degree theses aims is to raise the capacity factor for this heating plant. To achieve this objective, a survey of how grain dryers and absorption chillers could increase the heat load in the summer has been performed. With grain dryers that only dries wheat, the capacity factor for the geothermal heating plant in Miskolc increased by 2.6 % and by 4.4 % for the absorption chiller. Although surveys have been carried out for a specific case the idea can be implemented in other heating plants. Keywords: Capacity factor, geothermal energy, wheat dryers and absorptions chiller.
7

Metodologia de micrositing para terrenos complexos baseada em CFD com softwares livres de código aberto

Radünz, William Corrêa January 2018 (has links)
Micrositing é o campo do posicionamento estratégico dos aerogeradores na área do parque eólico visando a con guração mais promissora em termos econômicos ou de produção. Dado que em terrenos complexos as características do vento variam na área do parque eólico de forma não-linear, emprega-se a modelagem numérica do vento por CFD para extrapolar os dados medidos para toda a região. O presente trabalho consiste no desenvolvimento de uma metodologia de micrositing em terrenos complexos capaz de auxiliar no projeto do layout e seleção do tipo e altura de eixo do aerogerador que maximiza o fator de capacidade (FC) utilizando softwares livres de código aberto. A metodologia consiste na simulação do vento para várias direções de incidência, assimilação das medições, convers ão de velocidade em densidade de potência, ponderação por frequência de ocorrência de cada direção, sobreposição, seleção das coordenadas dos aerogeradores e cálculo do FC para diversas con gurações de tipo e altura de eixo dos aerogeradores. Veri cação, validação e seleção das constantes do modelo de turbulência é realizada anteriormente às simulações Veri cou-se que o modelo k- produziu um escoamento horizontalmente homog êneo e que o melhor desempenho na validação foi obtido com a escolha de constantes para escoamentos atmosféricos. A metodologia foi demonstrada em uma região de terreno complexo em que o FC do parque eólico proposto apresentou caráter convergente com o re no progressivo da malha, porém oscilatório em termos do número de direções simuladas. Por m, obteve-se FC brutos superiores a 40% para as cinco melhores con gurações e de aproximadamente 52% no melhor caso, indicando bom potencial eólico. A metodologia foi capaz de preencher uma lacuna na literatura cientí ca de micrositing ao possibilitar o planejamento do layout, tipo de aerogerador e altura de eixo, bem como a estimativa da produção e FC brutos da usina em terrenos complexos. Além disso, a estrutura de trabalho com o uso de recursos computacionais livres e de código aberto reforça o caráter de desenvolvimento contínuo, compartilhamento e transparência da metodologia. / Micrositing is the eld concerned with the strategic positioning of wind turbines in the wind farm area aimed at the most promissing con guration economically- or yield-wise. Given the wind characteristics vary non-linearly across the wind farm area in complex terrain, numerical wind modeling with CFD is employed to extrapolate the measured data to the whole site. The present work consists of the development of a micrositing methodology in complex terrain capable of assisting the layout project and selection of wind turbine type and hub height that maximizes the capacity factor (CF) using free and open-source software. The methodology consists of simulating the wind for a number of incoming directions, assimilation of measurements, conversion of wind speed into power density, weighing by frequency of occurrence of each direction, overlapping, selection of wind turbine coordinates and CF calculation for a number of wind turbine types and hub heights. Veri cation, validation and selection of turbulence model constants is performed previous to the simulations It was veri ed that the k- model is able to sustain horizontally-homogeneous ow and that the classic atmospheric ow constants performed best in the validation step. The methodology was demonstrated in a complex terrain region for which the proposed wind farm CF showed converging behavior with progressive mesh re nement, however oscillating with the number of wind directions simulated. Ultimately, CF greater than 40% were obtained with the ve best performing con gurations and approximately 52% in the best case scenario, suggesting good wind potential. The methodology was capable of lling a major gap in the scienti c literature of micrositing for allowing the layout planning, selection of wind turbine type and hub height, as well as gross production estimates and CF for the wind farm in complex terrain. Additionally, the free and open-source-based framework strengthens the continuous development, sharing and transparency of the methodology.
8

Metodologia de micrositing para terrenos complexos baseada em CFD com softwares livres de código aberto

Radünz, William Corrêa January 2018 (has links)
Micrositing é o campo do posicionamento estratégico dos aerogeradores na área do parque eólico visando a con guração mais promissora em termos econômicos ou de produção. Dado que em terrenos complexos as características do vento variam na área do parque eólico de forma não-linear, emprega-se a modelagem numérica do vento por CFD para extrapolar os dados medidos para toda a região. O presente trabalho consiste no desenvolvimento de uma metodologia de micrositing em terrenos complexos capaz de auxiliar no projeto do layout e seleção do tipo e altura de eixo do aerogerador que maximiza o fator de capacidade (FC) utilizando softwares livres de código aberto. A metodologia consiste na simulação do vento para várias direções de incidência, assimilação das medições, convers ão de velocidade em densidade de potência, ponderação por frequência de ocorrência de cada direção, sobreposição, seleção das coordenadas dos aerogeradores e cálculo do FC para diversas con gurações de tipo e altura de eixo dos aerogeradores. Veri cação, validação e seleção das constantes do modelo de turbulência é realizada anteriormente às simulações Veri cou-se que o modelo k- produziu um escoamento horizontalmente homog êneo e que o melhor desempenho na validação foi obtido com a escolha de constantes para escoamentos atmosféricos. A metodologia foi demonstrada em uma região de terreno complexo em que o FC do parque eólico proposto apresentou caráter convergente com o re no progressivo da malha, porém oscilatório em termos do número de direções simuladas. Por m, obteve-se FC brutos superiores a 40% para as cinco melhores con gurações e de aproximadamente 52% no melhor caso, indicando bom potencial eólico. A metodologia foi capaz de preencher uma lacuna na literatura cientí ca de micrositing ao possibilitar o planejamento do layout, tipo de aerogerador e altura de eixo, bem como a estimativa da produção e FC brutos da usina em terrenos complexos. Além disso, a estrutura de trabalho com o uso de recursos computacionais livres e de código aberto reforça o caráter de desenvolvimento contínuo, compartilhamento e transparência da metodologia. / Micrositing is the eld concerned with the strategic positioning of wind turbines in the wind farm area aimed at the most promissing con guration economically- or yield-wise. Given the wind characteristics vary non-linearly across the wind farm area in complex terrain, numerical wind modeling with CFD is employed to extrapolate the measured data to the whole site. The present work consists of the development of a micrositing methodology in complex terrain capable of assisting the layout project and selection of wind turbine type and hub height that maximizes the capacity factor (CF) using free and open-source software. The methodology consists of simulating the wind for a number of incoming directions, assimilation of measurements, conversion of wind speed into power density, weighing by frequency of occurrence of each direction, overlapping, selection of wind turbine coordinates and CF calculation for a number of wind turbine types and hub heights. Veri cation, validation and selection of turbulence model constants is performed previous to the simulations It was veri ed that the k- model is able to sustain horizontally-homogeneous ow and that the classic atmospheric ow constants performed best in the validation step. The methodology was demonstrated in a complex terrain region for which the proposed wind farm CF showed converging behavior with progressive mesh re nement, however oscillating with the number of wind directions simulated. Ultimately, CF greater than 40% were obtained with the ve best performing con gurations and approximately 52% in the best case scenario, suggesting good wind potential. The methodology was capable of lling a major gap in the scienti c literature of micrositing for allowing the layout planning, selection of wind turbine type and hub height, as well as gross production estimates and CF for the wind farm in complex terrain. Additionally, the free and open-source-based framework strengthens the continuous development, sharing and transparency of the methodology.
9

Cearà e a tendÃncia de uma matriz energÃtica com geraÃÃo predominantemente eÃlio-elÃtrica / Cearà and the trend of an energy matrix generating predominantly aeolian-electric

Nicorray de Queiroz Santos 29 September 2015 (has links)
Diante do cenÃrio atual, a substituiÃÃo do tradicional modelo de geraÃÃo hidrotÃrmico para hidroeÃlioelÃtrico no Brasil à bastante promissor. Deve-se ressaltar que o sistema elÃtrico brasileiro tem se baseado, hà dÃcadas, na geraÃÃo hidrÃulica auxiliada por fontes tÃrmicas oriundas de combustÃveis fÃsseis. Recentemente, fontes de energia renovÃvel como a de biomassa, a solar e a eÃlica vÃm tambÃm sendo utilizadas. A participaÃÃo das fontes eÃlicas tem sido significante desde 2005, tendo o Estado do Cearà demonstrado grande potencial para exploraÃÃo desse recurso. Para amparar essa inserÃÃo na matriz energÃtica cearense, os perfis dos fatores de capacidades sÃo avaliados, neste trabalho, visando o planejamento de produÃÃo de energia elÃtrica nos parques eÃlicos. Para os parques eÃlicos em operaÃÃo, constata-se que a velocidade mÃdia horÃria dos ventos ao longo do perÃodo analisado à de 8,54 m/s, conforme base de dados analisada entre 2012 e 2014. As funÃÃes de probabilidade de Rayleigh e Weibull permitiram tambÃm comparar os fatores de capacidade encontrados na simulaÃÃo com os dados verificados, entre os anos 2009 e 2014, em 35 plantas eÃlicas enquadradas, conforme procedimento de rede do ONS, com o objetivo de avaliar a variaÃÃo desse indicador. AlÃm disso, à possÃvel analisar comparativamente o valor real dos fatores de capacidade em funÃÃo dos valores planejados. O fator de capacidade mÃdio, determinado empiricamente, nas plantas em operaÃÃo à 39,9%, sendo que o valor correspondente Ãs curvas de distribuiÃÃo de probabilidade da velocidade do vento, o FC mÃdio, à 48%. Dessa forma, conclui-se que a alteraÃÃo do modelo hidrotÃrmico para hidroeÃlicoelÃtrico para algumas regiÃes do Brasil à viÃvel e de significativa importÃncia, tendo em vista os cenÃrios atu-ais de nossa reserva hÃdrica. O estudo ainda permite constatar que os parques eÃlicos atualmente representam 23,7% de participaÃÃo da demanda de carga no Estado do CearÃ, que corresponde atualmente a 2 GWp. Assim, à perfeitamente possÃvel se alterar a participaÃÃo para 40%, aumentando-se em 12,3% a capacidade instalada no Estado. Em outros termos, isso significa aumentar a atual participaÃÃo de 1,1 GW para 2 GW de potÃncia instalada, sendo que o fator de capacidade mÃdio de 475 MW mÃdios ao ano passaria a ser de 800 MW mÃdio, o que permitiria a maior diversificaÃÃo da matriz energÃtica cearense. Essa diferenÃa à estimada em 325 MW mÃdios, o que corresponde a mais 30 parques eÃlicos de 30 MW cada. / Given the current scenery in Brazil, the replacement of the traditional hydrothermal-based power generation model for a hydro/wind-based one is very promising. It is worth to mention that the Brazilian power system has been based on hydropower generation for decades, but the energy matrix was gradually supplemented by the addition of thermal sources derived from fossil fuels. Recently, renewable energy sources such as biomass, solar, and wind have also been included. Within this context, the participation of the wind power has become significant since 2005, while the state of Cearà has shown great potential for the exploitation of such energy resource. In order to support the integration of the wind power to Cearà energy matrix, the profiles of capacity factors are evaluated in this work aiming at energy planning regarding wind farms. Considering the wind farms currently in operation, it can be stated that the hourly average wind speed for the analyzed period is 8.54 m/s for the database among the years 2012 and 2014. The Rayleigh and Weibull distribution functions also allow comparing the capacity factors obtained in simulation tests and actual data for the period between 2009 and 2014, involving 35 wind farms, defined according to the ONS grid procedures. Besides, it is possible to effectively compare the actual capacity factors with the predicted ones. The average capacity factor, which has been determined empirically in operating plants, is 39.9%, while the value corresponding to the distribution function curves, the FCavg, is 48%. Thus, the replacement of the current hydrothermal generation model for a hydro-wind-power-based one, in some regions of Brazil, is viable and of great importance within the current scenery of water reserves. The study also reveals that wind farms now account for 23.7% of the load demand in the state of CearÃ, which is currently equal to 2 GWp. It is then possible to increase its contribution to 40%, thus increasing the installed capacity by 12.3%. In other words, it implies increasing the installed power from 1.1 GW to 2 GW, while the average capacity factor of 475 MWavg per year is increased to 800 MWavg, with the consequent diversification of Cearà energy matrix. This difference is estimated at 325 MWavg, which corresponds to more than 30 wind farms rated at 30 MW each
10

Análise operacional de um sistema fotovoltaico com alta concentração de 10kWp interligado à rede

URIBE, Francisco Jose Buelvas 13 August 2015 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-07-20T15:19:24Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) ANÁLISE OPERACIONAL DE UM SISTEMA FOTOVOLTAICO COM ALTA CONCENTRAÇÃO DE 10 kWp INTERLIGADO À REDE.pdf: 7127801 bytes, checksum: 39d3f0fe3404be063b56673557bb9d3d (MD5) / Made available in DSpace on 2016-07-20T15:19:24Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) ANÁLISE OPERACIONAL DE UM SISTEMA FOTOVOLTAICO COM ALTA CONCENTRAÇÃO DE 10 kWp INTERLIGADO À REDE.pdf: 7127801 bytes, checksum: 39d3f0fe3404be063b56673557bb9d3d (MD5) Previous issue date: 2015-08-13 / CNPq / No presente estudo foi avaliado o comportamento da eficiência na geração de energia, desempenho e influência sobre os parâmetros de operação da rede elétrica de um Sistema Fotovoltaico de Alta Concentração (HCPV- High Concentrating Photovoltaics) interligado à rede em condições reais de operação. O sistema foi instalado no Departamento de Energia Nuclear (DEN) da UFPE. Os ensaios experimentais, realizados com medições do recurso solar incidente no local de instalação, permitiram estabelecer o comportamento da energia gerada em condições instantâneas, médias diárias e mensais. O sistema HCPV foi comparado com um sistema convencional de Silício policristalino (Si-P), de capacidade similar, operando nas mesmas condições meteorológicas durante o mesmo período. Ao longo do período de análise verificou-se que devido ao alto índice de nebulosidade, o recurso solar em Recife não promove condições vantajosas para o aproveitamento da elevada eficiência de conversão do sistema HCPV, em média 22%, chegando a níveis de 26%. Quando comparado com o sistema Si-P, embora o sistema HCPV apresente uma eficiência maior, o mesmo gerou, em Recife, 22% a menos de energia que o sistema Si-P, devido à capacidade do Si-P de aproveitar a irradiância global, em média 40% maior que a direta normal vista pelo sistema HCPV. Para realizar uma comparação entre o desempenho e a energia gerada pelos dois sistemas foi utilizado o índice de desempenho (PR - Performance Ratio) e o fator de capacidade. Uma simulação com base nos resultados experimentais, comparando os dois sistemas, foi realizada para as cidades de Petrolina (PE), São Martinho (RS) e Barra (BA). Verificou-se que o sistema HCPV é capaz de gerar 9% a mais de energia em Petrolina que o Si-P. Os valores obtidos para São Martinho e Barra foram 22% e 32% superiores, respectivamente. Os resultados mostram que o sistema HCPV pode vir a ser viável para as localidades, com elevados níveis de irradiância direta. Foi possível verificar que devido à pequena potência instalada do sistema HCPV (10 kWp) - comparada ao nível de consumo de energia do DEN - não houve influência apreciável sobre os parâmetros de operação da rede elétrica. / This work presents an analysis of the power generation, efficiency’s behavior, performance and influence on the electrical grid of a High Concentrating Photovoltaic system (HCPV) connected to the grid operating under real conditions. The system was installed at Nuclear Energy Department (DEN) - UFPE. The experimental tests, with measurements of the solar radiation resources at the installation site, allowed establishing the behavior of generated energy in instantaneous conditions, daily and monthly averages. The HCPV system was compared with a conventional polysilicon (Si-P) system, similarly capacity, operating under the same weather conditions over the same period. Along the analysis period, it was found that due to the high amount of cloud cover, the solar resource in Recife does not promote favorable conditions to take advantage of the high conversion efficiency of the HCPV system, with average of 22%, reaching levels of 26%. When compared with the Si-P system, although the HCPV presents higher efficiency, it has generated, in Recife, 22% less energy than the Si-P system due to the ability of the Si-P to take advantage of the global irradiance, in average 40% higher than the direct normal irradiance “view” by the HCPV system. Making a comparison of the performance and of the energy generated by the two systems we used the performance ratio (PR - Performance Ratio) and capacity factor. A simulation based on the experimental results, comparing the systems, was held for the cities of Petrolina (PE), St. Martin (RS) and Barra (BA). It was found that the HCPV system is capable to generate 9% more energy in Petrolina than the Si-P. The values obtained for St. Martin and Barra were 22% and 32% larger, respectively. The results show that the HCPV system could be viable for locations with high levels of direct irradiance. The analysis of the behavior of the HCPV system connected to electrical grid shows that due to the small installed capacity of HCPV system (10kWp) - compared to the level of the Nuclear Energy Department power consumption - no appreciable influence on the operating parameters of the electric grid could be detected.

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