Dissertations / Theses on the topic 'Fresnel concentrator solar plant'

Ce manuscrit aborde la modélisation numérique d’une installation commerciale utilisant la technologie de concentration solaire linéaire Fresnel pour la production directe de vapeur d’eau à haute pression (70 bars) qui sera valorisée en énergie électrique grâce à un groupe turbo-alternateur de 10 MW. Cette installation nommée centrale solaire eLLO, située sur le plateau Cerdan dans les Pyrénées-Orientales, France, fait suite à l’expérience positive de SUNCNIM sur la conception et la réalisation d’un prototype de concentrateur linéaire Fresnel à génération directe de vapeur à La Seyne-sur-Mer, Var, France. Néanmoins, le changement d’échelle et les premières années d’exploitation révèlent le besoin de redéfinir les sousmodèles utilisés pour le dimensionnement du projet eLLO.Ainsi, le projet de recherche présenté dans ce document a pour objectif de développer un modèle global de la centrale pour étudier ses performances et proposer des pistes d’optimisations de l’installation et des stratégies opératoires. Un modèle optique, développé sur la base de la méthode de lancer de rayons, permet de définir le comportement optique des concentrateurs solaires pour toutes les positions solaires et d’étudier les particularités des champs solaires de la centrale eLLO comme l’orientation et l’inclinaison des concentrateurs, la non-coplanarité des récepteurs solaires ou encore la distribution asymétrique des rayons de cintrage des miroirs. Une étude thermique expérimentale et un modèle numérique permettent de redéfinir la caractérisation des pertes thermiques des récepteurs solaires. La validation de ces études est effectuée en comparant les résultats aux performances optiques et thermiques d’autres concentrateurs solaires linéaires Fresnel développés par des industriels ou des laboratoires. Finalement, ces résultats sont utilisés comme donnée d’entrée du modèle global qui est constitué de l’ensemble des composants et des régulations, du récepteur solaire au groupe turbo-alternateur du cycle thermodynamique de Hirn mis en oeuvre à la centrale. Validé en comparant les résultats numériques aux données expérimentales, le modèle global permet de décrire le comportement dynamique de l’installation industrielle et ainsi de mettre en évidence des pistes d’améliorations du procédé. Les connaissances apportées par le modèle optique et l’étude des pertes thermiques permettent de proposer une stratégie de régulation de la recirculation de l’eau dans les champs solaires ayant pour objectif 80 % de vapeur à la sortie des lignes solaires. Ce document se termine par une analyse des données expérimentales issues de la centrale et la caractérisation de certains indicateurs de performance qui sont, à notre connaissance, une première dans la littérature scientifique pour une installation commerciale<br>This manuscript presents the numerical modelling of a commercial plant using Fresnel linear solar concentrator technology for the direct production of high-pressure (70 bar) steam, which will be converted into electrical energy using a 10 MW turbine-generator set. This installation, known as the eLLO solar power plant, located on the Cerdan plateau in the Pyrénées-Orientales, France, follows SUNCNIM's positive experience in designing and building a linear Fresnel concentrator prototype for direct steam generation in La Seyne-sur-Mer, Var, France.Nevertheless, the change of scale and the first years of operation revealed the need to redefine the sub-models used for sizing the eLLO project. The aim of the research project presented in this document is therefore to develop a global model of the power plant in order to study these performances and propose ways of optimizing the installation and the operating strategies. An optical model, developed on the basis of the ray-tracing method, is used to define the optical behaviour of the solarconcentrators for all solar positions, and to study the particularities of the eLLO power plant's solar fields, such as the orientation and inclination of the concentrators, the non-coplanarity of the solar receivers and the asymmetric distribution of the mirrors bending radius. An experimental thermal study and a numerical model are used to redefine the characterizationof solar receiver heat losses. These studies are validated by comparing the results with the optical and thermal performance of other Fresnel linear solar concentrators developed by industries or laboratories.Finally, these results are used as input data for the global model, which comprises all components and controls, from the solar receivers to the turbo-alternator unit of the Hirn thermodynamic cycle implemented at the plant. Validated by comparing numerical results with experimental data, the global model can be used to describe the dynamic behaviour of the industrial plant, and thus highlights potential areas of process improvement. The knowledge provided by the optical model and the heat loss study enables to come up with a strategy for regulating water recirculation in the solar fields, with a target of 80% steam at the outlet of the solar lines. The manuscript concludes with an analysis of experimental data and the characterization of performance indicators which, to our knowledge, is a first achievement in the scientific literature for a commercial installation

Thesis (MScEng)--Stellenbosch University, 2013.<br>ENGLISH ABSTRACT: This study describes the design and construction of a low-cost linear Fresnel solar concentrator. Ray-trace simulation models that analyse optical performance were developed and then used to perform sensitivity analyses of various characteristics of linear Fresnel concentrators. The design of a small-scale concentrator was optimised using the simulation models, after which the concentrator was constructed in the solar laboratory. The concentrator consists of a single-motor tracking system, flat primary mirrors and a low-cost secondary concentrator that approximates a compound parabolic concentrator. Testing revealed satisfactory performance that was comparable to the simulation models’ prediction. The construction of a low-cost solar concentrator that can replace existing thermal sources for the generation of power and process heat is thus achievable.<br>AFRIKAANSE OPSOMMING: Die ontwerp en konstruksie van 'n laekoste- lineêre Fresnel-sonkonsentreerder word in hierdie studie beskryf. Stralingsimulasiemodelle wat optiese werksverrigting analiseer is ontwikkel en gebruik om sensitiwiteitsanalises van die verskillende eienskappe van lineêre Fresnel-konsentreerders te doen. Die modelle is verder gebruik om die ontwerp van 'n kleinskaalse konsentreerder te optimeer, waarna die konsentreerder in die sonlaboratorium gebou is. Die konsentreerder bestaan uit 'n enkelmotorvolgingstelsel, plat primêre spieëls en 'n laekoste- sekondêre konsentreerder soortgelyk aan 'n saamgestelde, paraboliese konsentreerder. Toetsing dui bevredigende werksverrigting aan, vergelykbaar met wat die simulasiemodelle voorspel het. Dit is dus moontlik om 'n laekoste-sonkonsentreerder wat bestaande termiese bronne vir kragopwekking en proseshittegenerasie kan vervang, daar te stel.

The Monte Carlo-type statistical ray-tracing method was used to investigate the performance of the line-focusing Fresnel mirror solar concentrator. An optical model of the line-focusing Fresnel mirror concentrator using the statistical ray-tracing approach was developed. Many rays of sunlight from the solar disk were selected at random and traced through the concentrator in this model. This optical model permits calculation of the local and geometric concentration ratios. The latter requires an energyloss analysis. Small sun-tracking errors of the diurnal or transverse type were included in the model.Based on the optical model and the Monte Carlo-type statistical ray-tracing method, a computer program was written implementing the model and computations using Pascal. To facilitate performance comparisons, a baseline concentrator design was adopted. To study the effects of imperfect tracking, performance data were generated for small tracking errors up to approximately two and one-half degrees. The selected mirror configuration permitted comparisons between the statistical approach and previous applications of the "extreme ray" analysis for an imperfectly tracking mirror concentrator.Simulation results demonstrated that the concentration characteristics are highly sensitive to the tracking error. The geometric concentration ratio dramatically decreases when the tracking error increases, which is the same as the "extreme ray" analysis. Results of some typical numerical calculations are presented graphically and discussed.<br>Department of Physics and Astronomy

The solar concentration performance of a tracking, flat-base, line-focusing Fresnel mirror was investigated in this study. The Fresnel mirror consists of flat mirror strips situated on a base and oriented at appropriate angles to focus incident light to a desired line. Simple optical ray tracing and energy conservation were used to develop a mathematical model of the concentrator assuming small or zero diurnal tracking errors. The model analyzed the concentrator design and provided detailed expressions for the geometric evaluation of the concentrated sunlight rays in the focal plane above the mirror. The local concentration ratio and the geometric concentration ratio were introduced to describe the intensity profile in the focal plane and the average concentration of sunlight on a target absorber. Included in the model were losses of incident sunlight due to imperfect reflection, nonreflecting portions of the base, and blockage by adjacent mirror strips when imperfect tracking occurs.Based on the analytical model and using the Ada high level language, a computer program was written to simulate the concentrator. To facilitate performance comparisons, a baseline concentrator design was adopted. To study the effects of imperfect tracking, performance data were generated for small tracking errors up to approximately two and one-half degrees. The effects of design variations were studied by varying the concentrator focal length, strip width, and base width.Simulation results demonstrated that the concentration characteristics were highly sensitive to tracking error. Intensity profile shifts relative to the target caused the highest losses in intercepted sunlight.Design decisions were found to dramatically affect the concentration character- istics. For the baseline concentrator under perfect tracking conditions, an optimum focal length was identified. Except for the disadvantage of added costs, decreased strip widths was found to be a way to increase both the maximum and average concentration ratio for the absorber. Using smaller strip widths might, however, critically affect the energy intercepted by the target under imperfect tracking. Increasing the concentrator base width increased the total amount of power in the focal plane, with a higher maximum concentration ratio and additional tailing of the intensity profile.<br>Department of Physics and Astronomy

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico<br>Amid the great crisis of the energy, new methods for electric power generation, especially those do not harm the environment, are constantly sought to meet the growing need worldwide. Among them, the use of Fresnel linear concentrators becomes increasingly feasible, due to have lower cost in comparison to other types of solar concentrators. Thus, the project seeks to develop techniques that optimize use of the system where the main objective is to implement and validate the tracking system for a prototype of linear Fresnel solar concentrator, operating between approximately 7:30 and 16:30 in Fortaleza, CearÃ. For that, it used microcontrollers, sensors and motors to design a system capable of tracking Solar light system. The characterization and validation of the inductive position sensor used is also an important part of the work. To perform the tracking system, have been used a theoretical methodology for relative location of the sun, beyond the gain scheduling technique in control of employee movement. The position sensor validation have a maximum error than 0.3Â. Therefore, can consider that, with the use of the techniques employed for the achievement of system of control, the medium error obtained was about 0.06Â, making the design perform the concentration of solar rays in the absorber concentrator with a maximum deviation of 0.5Â, providing the desired reliability for system use.<br>Em meio Ãs grandes crises no ambiente energÃtico novos mÃtodos para geraÃÃo de energia elÃtrica, principalmente aqueles que nÃo agridem o meio ambiente, sÃo procurados constantemente para suprir a crescente necessidade mundial. Dentre eles, o uso de concentradores Solares do tipo Fresnel linear torna-se cada vez mais viÃvel, devido possuir custo inferior a outros tipos de concentradores solar. Com isso, procura-se desenvolver tÃcnicas que otimizem o uso do modelo onde o principal objetivo deste trabalho à implementar e validar o sistema de rastreamento de um protÃtipo de concentrador solar Fresnel linear, com funcionamento compreendido aproximadamente entre 7:30 e 16:30 h, na cidade de Fortaleza, CearÃ. Para tanto, utilizou-se microcontroladores, sensores e motores para projetar um sistema capaz de rastrear a luz Solar. A caracterizaÃÃo e validaÃÃo do sensor de posiÃÃo indutivo utilizado tambÃm à parte importante do trabalho. Para a realizaÃÃo do rastreamento empregou-se uma metodologia teÃrica para localizaÃÃo relativa do Sol, alÃm da tÃcnica de escalonamento de ganho no controle do movimento empregado. A validaÃÃo do sensor de posiÃÃo foi realizada encontrando-se um erro mÃximo em torno de 0,3Â. Portanto, pode-se considerar que, com a utilizaÃÃo das tÃcnicas abordadas para a realizaÃÃo do controle do sistema o erro mÃdio obtido foi cerca de 0,06Â, fazendo com que o projeto realizasse a concentraÃÃo dos raios solares no absorvedor do concentrador com um desvio mÃximo de 0.5Â, fornecendo ao sistema a confiabilidade desejada para sua utilizaÃÃo.

Submitted by Morgana Silva (morgana_linhares@yahoo.com.br) on 2016-09-23T16:07:12Z No. of bitstreams: 1 Dissertação.pdf: 2848624 bytes, checksum: f5075c15190584601d6a5374e1d06fd7 (MD5)<br>Made available in DSpace on 2016-09-23T16:07:12Z (GMT). No. of bitstreams: 1 Dissertação.pdf: 2848624 bytes, checksum: f5075c15190584601d6a5374e1d06fd7 (MD5) Previous issue date: 2016-06-22<br>Brazil has as a main source for production of electricity the dams using water to drive the turbines and as a secondary source are used the thermoelectric power plants that use fuel oil for electric power production. Both generate a large environmental impact, due to the fact of the dams need huge areas for its construction, which often leads to destruction of important ecosystems in the region where it will be installed the hydroelectric plant, besides the fact that they need the rainfall cycle so that the dams have the operating capacity, while the thermoelectric power plants burn fossil fuels thus increasing emissions of CO2 to the atmosphere. An alternative to the solution of the problems mentioned above is the use of renewable sources of energy, with emphasis on this work. Solar energy can be divided into two parts: thermal and photovoltaic. This work it is focused on thermal use of solar energy, with a Fresnel-type solar concentrator to heat water, which will trigger a cooling system environment with the use of desiccant rotors. The choice of type Fresnel collector gave the field of development of this hub is still in constant growth and by the fact that even occupy a relatively small area when compared to other solar thermal concentrators, in addition to its construction be simple and low cost when again compared to other solar concentrators.<br>O Brasil tem como fonte principal para produção de energia elétrica as hidrelétricas que utilizam água para movimentar as turbinas e como fonte complementar são utilizadas as termoelétricas que usam óleo combustível para produção de energia elétrica. Ambas geram um grande impacto ambiental, devido ao fato das hidrelétricas necessitarem de enormes áreas para a construção das represas, o que muitas vezes acarreta na destruição de ecossistemas importantes para a região onde irá ser instalada a hidrelétrica, além do fato que elas necessitam do ciclo das chuvas para que as represas possuam capacidade de operação, enquanto que as termoelétricas queimam combustíveis fosseis, aumentando assim as emissões de CO2 para a atmosfera. Uma alternativa para a solução dos problemas citados anteriormente é a utilização de fontes renováveis de energia, dando ênfase neste trabalho a energia solar. A energia solar pode ser dividida em duas vertentes: térmica e fotovoltaica. Este trabalho está voltado para a utilização térmica da energia solar, através da utilização de um concentrador solar do tipo Fresnel para o aquecimento de água, a qual irá acionar um sistema de refrigeração de ambientes com a utilização de rotores dessecantes. A escolha do coletor do tipo Fresnel se deu pelo campo de desenvolvimento deste concentrador estar ainda em constante crescimento e pelo fato do mesmo ocupar uma área relativamente pequena quando comparado com outros concentradores solares térmicos, além de sua construção ser simples e de baixo custo quando novamente comparada a outros concentradores solares.

This work investigates the Fresnel-lens-based solar concentrator-receiver system in a multi-perspective manner to design, test and fabricate this concentrator with high-efficiency photon and heat outputs and a minimized effect of chromatic aberrations. First, a MATLAB®-incorporated algorithm optimizes both the flat-spot and the curved lens designs via a statistical ray-tracing methodology of the incident light, considering all of its incidence parameters. The target is to maximize the solar ray intensity on the receiver's aperture, and therefore, achieve the highest possible focal flux. The algorithm outputs prismatic and dimensional geometries of the Fresnel-lens concentrator, which are simulated by COMSOL® Multiphysics to validate the design. For the second part, a novel genetically-themed hierarchical algorithm (GTHA) has been investigated to design Fresnel-lens solar concentrators that match with the distinct energy input and spatial geometry of various thermal applications. Basic heat transfer analysis of each application decides its solar energy requirement. The GTHA incorporated in MATLAB® optimizes the concentrator characteristics to secure this energy demand, balancing a minimized geometry and a maximized efficiency. Two experimental applications were selected from literature to validate the optimization process, a solar welding system for H13 steel plates and a solar Stirling engine with an aluminum-cavity receiver attached to the heater section. In each case, a flat Fresnel-lens with a spot focus was algorithmically designed to supply the desired solar heat, and then a computer simulation of the optimized lens was conducted showing great comparability to the original experimental results. Thirdly, the prismatic geometry of the Fresnel lens was further optimized through a statistical approach that incorporates laws of light refraction and trigonometry. The proposed design produces high focal irradiance that is more suitable for thermal applications. The motivation was to enhance the tolerability of a flat Fresnel-lens concentrator to tracking errors, without the use of secondary optics or sophisticated, and normally costly, meticulous tracking equipment. A comparative simulation analysis was conducted for two case studies from literature, each with a different design method. Fresnel lenses optimized by this work enhanced the concentration acceptance product (CAP) significantly, compared to that in literature. Then, this work introduced an innovative code-based, detailed, and deterministic geometrical approach, which couples the optimization of the Fresnel lens primary optical element (POE) and the dome-shaped secondary optical element (SOE). The objective was to maximize the concentration acceptance product, while using the minimum SOE and receiver geometries at a given f-number and incidence angle (also referred to as the tracking error angle). The laws of polychromatic light refraction along with trigonometry and spherical geometry were utilized to optimize the POE grooves, SOE radius, receiver size, and SOE–receiver spacing. Two literature case studies were analyzed to verify this work's optimization, and the equivalent POEs designed by this work, with optimized SOEs, showed a significant enhancement in the CAP values compared to that of literature. Lastly, four methods for prototyping the Fresnel lens were discussed and experimentally tested; 3D printing, acrylic resin casting, direct CNC machining in acrylic and hot embossing. Once tested, the methods of CNC machining and hot embossing of acrylic proved to be the most promising in terms of cost, fabrication time, and concentration effectiveness. Future work will focus on enhancing the algorithmic design and improving the quality of lens fabrication.

This master thesis deals with the performance calculations of a 9MW linear Fresnel CSP plant withdirect steam generation built by the Solar Division of the CNIM Company. The aim was to calculate theannual electricity production taking into account the weather conditions as well as some steam storage.At first, a steam accumulator model was developed with Excel, in order to estimate the pressureevolution in the tanks during the charging, storage and discharging processes. The data obtained withthis model was then integrated to the thermodynamic cycle model, programmed with Excel, whichcalculated the electrical power production knowing the thermal power available in the solar field. Theelectricity production calculations were made every 600 seconds during one year.To improve the results accuracy, the influence of the plant location slope was estimated, calculating theequivalent azimuth and elevation angles in a new spherical coordinates system. For an average slope of4.21° at the plant location, the annual thermal energy gain is 14.4% (with a gain up to 60% duringwinter days) and the annual electricity production is increased by 12.59%. The influence of frost on themirrors during cold and humid nights was also estimated with a simple model of the energy needed toheat up a constant layer of ice. Depending on the assumptions, the electricity production losses werebetween 1.27 and 2.84% of annual electricity production. The losses due to plant shutdowns set by theelectrical network manager RTE during the snowmelt months were also estimated. The annualelectricity production could decrease by 8.02 to 11.57 % because of the load management, dependingon the days during which the plant is shutdown.Finally, an economic optimisation was led with prices estimated by CNIM, which gave an optimal solarfield design with 31 lines and 5 steam accumulators. The payback time would then be 9.887 years.

Ce travail a pour objet de développer une nouvelle technologie de l’énergie solaire à concentration. Il porte sur la présentation du concept, la réalisation prototypique et l’étude optique et énergétique d’un nouveau concentrateur solaire QingSun™. Ce concentrateur a une forme de parallélépipède rectangulaire et comporte des lentilles de Fresnel linéaires, des parois tapissées de miroir et d’un récepteur solaire mobile entraîné par un système de suivi à l’intérieur du caisson de concentration. Un modèle optique et un modèle énergétique ont été élaborés et validés avec une série d’expériences. Ils ont permis d’étudier le fonctionnement et les performances énergétiques du concentrateur. Une étude de l’influence paramétrique de l’inclinaison et l’orientation a été effectuée et a montré que l’inclinaison a plus d’influence que l’orientation sur les performances. Enfin, les performances énergétiques optimales du concentrateur ont été estimées<br>This work is for the purpose to develop a new solar concentrating technology. It covers the presentation of the concept, the prototype realization and the optical and energy study of a new solar concentrator QingSun™. This concentrator has a shape of rectangular parallelepiped and includes linear Fresnel lenses, mirror-lined walls and a mobile solar receptor controlled by a tracking system inside the casing. An optical model and an energy model were developed and validated with a series of experiments. The both models permitted us to examine the function and the energy performance of the concentrator. A parametric study of the influence of the tilt and the orientation was performed and showed that the tilt had more influence than the orientation. Finally, the optimal energy performance of this concentrator was estimated

Until a few decades ago few people could imagine that the photovoltaic, solar thermal and other power based on renewable resources, will become a reality. Today people from all over the world on the contrary try at full blast derive benefit from of all possible available source. Using sunlight as a source of energy is first enforced only for small devices such as calculators for charging the battery, but now we are able to produced energy from the sun to supply people around the world. Of course it is not possible supply consumer sector plus firm only from performances renewable power supply. Therefore endeavour is derive benefit from classical energy production at the same time with others power supply. The basic components of photovoltaic and solar thermal power are panels. The panels are made of different materials in different shapes and sizes. During production, the resulting effect looks in addition to costs associated with production. For photovoltaic and solar thermal power plant requires sufficient sunlight. The sunshine has biggest intensity on south of ours planets. Therefore endeavour is build lump these power station just in stand with bigger intensity sunshine. One of them is just Cyprus, too.

碩士<br>大同大學<br>機械工程學系(所)<br>97<br>Regarding to the low effectiveness of generating electrical power and the high cost of the solar cell, a concentrator system is needed for generation of more solar energy by solar cell to increase effectiveness and reduce cost. Fresnel lens could perform efficiently under large aperture optical system; therefore Fresnel lens was usually applied to the solar concentrator system. The genetic algorithm was integrated with the commercial program LightTool to design a non-imaging Fresnel lens. First several test functions were applied to verify the genetic algorithm. Then the search for optimal geometry parameter setting of Fresnel lens was conducted for maximization of energy effective and reduction of optical loss.

碩士<br>國立交通大學<br>光電工程系所<br>94<br>The major aim of photovoltaic (PV) concentrator technology is to improve the PV array performance per cost unit by concentrating optical components to increase the intensity of sunlight falling on the cell. By using concentrator it is possible to decrease the area of solar cell material being used in a system and therefore to reduce the dependence of the PV industry on the silicon stock imitations as well as reaching very high efficiencies, with sophisticated high cost cells. Better uniformity performance on solar cell and larger angular acceptance of field of view of concentrator system are the two major targets of research and development in constructing the optical concentration systems. On the other hand, the use of Fresnel lenses has been the main stream for optical concentrators because of its flexibility. The subject of this thesis study is to provide the design analysis of the Dome-shaped and Plated-shaped Fresnel concentrators in which dome-shaped concentrator has larger tolerance in light collection angle, while the planer-shaped has better performance in uniformity of energy distribution on solar cell. As a basic investigation, the role of single base prism in both types of Fresnel lenses has been clarified. The main results of this thesis are that we explored and designed the dome-shaped concentrators which can have tolerance angle upto 5 degrees. As for the plated-shaped Fresnel concentrator, because of the fabrication limitation of pitch size and the consideration of compact system, high non-uniformity of energy on solar cell is inevitable, hence we introduced aspheric surface in the middle portion and it is shown that better uniformity could be achieved significantly.

碩士<br>元智大學<br>光電研究所<br>93<br>Because of the low efficiency and high price of solar cell, we need a concentrator to collect sunlight onto the solar cell due to the efficiency and cost. Fresnel lens was usually used for a solar concentrator because of its good performance, especially in the large-diameter optical system. In this thesis, we’ll explain the principle of Fresnel lens and how to design it first. There is one thing we should pay attention to, that the Fresnel lens in the research is worked as refraction but diffraction. Based on geometrical optics, the size of each pitch on the surface is about 0.2 mm to 0.5 mm. Discuss the relation between the dispersion and the deviation of a prism, and design a non-imaging Fresnel lens which was consist of many minimum deviation prisms, and the non-imaging Fresnel lens should obey the edge ray principle. By using the optical software “TracePro”, we analyze the performance of the non-imaging Fresnel lens by simulations. We compared the non-imaging Fresnel lens with the imaging Fresnel lens that was used in solar concentrator. Then, we discussed the losses and proposed the policy to reform in future works.

碩士<br>國立中央大學<br>光機電工程研究所<br>99<br>This study presents the design of solar concentrator for Concentrated Photovoltaic (CPV) system. Firstly, the flat Fresnel lens model was constructed by Fresnel lens formula. The optical performance of the Fresnel lens under variations of prism pitches and the position of the solar cell were analyzed by ray tracing software ASAP. The simulation results showed that the acceptance angles and energy distribution of the Fresnel lens were not good enough. To improve the aforementioned drawback, different secondary optical elements (SOEs) designed by edge ray principle were proposed with the Fresnel lens. Parameter method is also applied with the optical simulations in order to find the best SOE design parameters. The two main influences of temperature variation on the Fresnel lens are change of index of refraction and thermal deformation of the Fresnel prisms. The thermal deformation of the Fresnel lens was analyzed by finite element method (FEM). The deformed lens geometry determined from FEM was imported into ray tracing simulation to investigate the effects of temperature variations on the Fresnel lens.

碩士<br>國立高雄應用科技大學<br>模具工程系<br>98<br>The shortage of energy has been noticed around the world. However, solar power is the richest and the most long-term nature of energy, with the characteristics of degeneration. If the solar power can be used properly, it helps to reduce the effects of greenhouse. Unfortunately, the efficiency for power generation efficiency of solar cells is low and expensive. As cost and efficiency of the test volume are concerned, we need a set of optical system to collect more sunlights in solar cells. As Fresnel Lens produce good results for optical system, it is usually employed in sets of optical devices to collect solar energy. In addition, Focus Type Fresnel Lens was used in solar concentrator system. It helps not only the original large-scale, low-density, and low interest rate of energy with volume (i.e., light and electromagnetic waves) focus on the concentration of radiation in the solar light, but also reduces the solar wafers area and volume to achieve high-density and high-interest rate purposes. The solar concentrator lenses, with Fresnel structure was designed in the current study. It combined with optical design, injection molding, injection compression molding and measure. As for the optical design, more specifically, the optical simulation software, Trace Pro, followed by the design of parameters changed Pitch, and the focal length were used to explore the impact parameters for the set of optical effects. For mold design and development, CAE Software (i.e., Moldflow Analysis) was employed in this study. The injection molding and injection compression molding were employed to make solar concentrator lenses in the experiment. In addition, the discussion of replication and optical effects was followed. In the present study, the outline replication ability of injection and injection compression molding were both over 95%. Moreover, the replication with injection compression molding was better than that with injection molding. The stress near the gate for the former was less obvious than that of latter one. High replication of solar concentrator lenses boosted solar cell more efficiently, the GaAs efficiency can achieve 30.50% with solar concentrator lenses and the power improves about 9 times. Keyword : Fresnel lens, optical design, injection compression molding, replication