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Shah, Syed Fawad Ali. "Intelligent Algorithms for a Hybrid FuelCell/Photovoltaic Standalone System : Simulation Of Hybrid FuelCell/Photovoltaic Standalone System". Thesis, Högskolan Dalarna, Datateknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:du-10046.
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The Intelligent Algorithm is designed for theusing a Battery source. The main function is to automate the Hybrid System through anintelligent Algorithm so that it takes the decision according to the environmental conditionsfor utilizing the Photovoltaic/Solar Energy and in the absence of this, Fuel Cell energy isused. To enhance the performance of the Fuel Cell and Photovoltaic Cell we used batterybank which acts like a buffer and supply the current continuous to the load. To develop the main System whlogic based controller was used. Fuzzy Logic based controller used to develop this system,because they are chosen to be feasible for both controlling the decision process and predictingthe availability of the available energy on the basis of current Photovoltaic and Battery conditions. The Intelligent Algorithm is designed to optimize the performance of the system and to selectthe best available energy source(s) in regard of the input parameters. The enhance function of these Intelligent Controller is to predict the use of available energy resources and turn on thatparticular source for efficient energy utilization. A fuzzy controller was chosen to take thedecisions for the efficient energy utilization from the given resources. The fuzzy logic basedcontroller is designed in the Matlab-Simulink environment. Initially, the fuzzy based ruleswere built. Then MATLAB based simulation system was designed and implemented. Thenthis whole proposed model is simulated and tested for the accuracy of design and performanceof the system.
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Ma, Jiya. "A Genetic Algorithm for Solar Boat". Thesis, Högskolan Dalarna, Datateknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:du-3488.
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Genetic algorithm has been widely used in different areas of optimization problems. Ithas been combined with renewable energy domain, photovoltaic system, in this thesis.To participate and win the solar boat race, a control program is needed and C++ hasbeen chosen for programming. To implement the program, the mathematic model hasbeen built. Besides, the approaches to calculate the boundaries related to conditionhave been explained. Afterward, the processing of the prediction and real time controlfunction are offered. The program has been simulated and the results proved thatgenetic algorithm is helpful to get the good results but it does not improve the resultstoo much since the particularity of the solar driven boat project such as the limitationof energy production
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Franklin, Ed. "Types of Solar Photovoltaic Systems". College of Agriculture, University of Arizona (Tucson, AZ), 2017. http://hdl.handle.net/10150/625568.
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5 p.Solar energy systems can help Arizona individuals, families, and businesses achieve energy conservation goals beyond the adoption of energy-efficient appliances, and LED bulbs. Which type of system is the best? Knowing which system to select is the first important question. This factsheet will focus on solar photovoltaic energy systems. The term photovoltaic refers to the conversion of light energy to electricity.
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Chan, Ngai Lam Alvin. "Solar electricity from concentrator photovoltaic systems". Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/14206.
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This thesis examines the prediction of concentrator photovoltaic system performance, and a model is presented where estimates are made using basic, fundamental material and atmospheric parameters, and successfully validated against measurements from a deployed system, to within 2% accuracy. A method to characterise the impact of individual atmospheric parameters on concentrator photovoltaic system performance is detailed and results are presented for potential deployment locations around the globe, demonstrating substantial differences in energy yield prediction accuracy if insufficient information is available, with up to 75% relative difference in energy yield and levelised cost of energy between basic and detailed simulations. In addition, the competitiveness of concentrator photovoltaic systems in different locations are benchmarked against existing technologies, showing significant geographical variation in their financial viability. The material quality in single and multijunction solar cells and its effect on the selection of optimal solar cell designs is investigated and the radiative efficiency of a device is proposed as a figure of merit to evaluate material quality. The optimal band gaps are shown to vary substantially depending on material quality at low solar concentrations, by hundred of milli-electron-volts, with ramifications for future solar cell designs. The impact of photon management, through radiative coupling, on cell performance is quantified for current and future high efficiency multijunction solar cell structures. Up to 5% enhancement due to radiative coupling can be expected for quad-junction solar cells, but current designs can expect below 1% enhancement. The work covered in this thesis has investigated and highlighted the potential problems associated with not fully understanding the atmospheric conditions in which concentrator photovoltaic systems operate, providing evidence and impetus for additional ground measurements or a drastic improvement in satellite-based measurement of atmospheric conditions. By integrating atmospheric parameters into an existing concentrator photovoltaic system modelling tool, new methods to characterise these conditions has been developed rigorously and accurately simulate system behaviour, a valuable resource to the field. In the design of optimal band gaps for multijunction solar cells, the work in this thesis shows that the material quality must be carefully considered in any design. A novel method has been developed to quantify material quality and provide a benchmark of state-of-the-art achieved values. The role of photon management in the form of radiative coupling is quantified, through the first examination of enhancement due to the effect, under realistic atmospheric conditions. This gives cell designers realistic expectations for performance enhancement.
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Vourazelis, Dimitrios G. "Optimization in solar heating/photovoltaic systems". Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA242363.
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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 1990.Thesis Advisor(s): Titus, Harold A. Second Reader: Michael, Sherif. "December 1990." Description based on title screen as viewed on March 30, 2010. DTIC Descriptor(s): Heat Transfer, Theory, Theses, Costs, Heating Elements, Fluid Dynamics, Photovoltaic Effect, Solar Heating, Swimming, Optimization, Installation. DTIC Identifier(s): Swimming Pools, Solar Heating, Photovoltaic Supplies, Filter Pumps, Theses. Author(s) subject terms: Optimization, Solar Heating, Photovoltaics. Includes bibliographical references (p. 57). Also available in print.
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Williams, Kristen. "Solar integration : applying hybrid photovoltaic/thermal systems". Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/3744.
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Goss, Brian. "Design process optimisation of solar photovoltaic systems". Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/19418.
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The design processes for solar photovoltaic (PV) systems is improved to achieve higher reliability and reduced levelised cost of energy (LCOE) throughout this thesis. The design processes currently used in the development of PV systems are reviewed. This review process included embedding the author in a project to deliver four rooftop PV systems which totalled a megawatt of installed generating capacity, which at the time represented very significant system sizes. The processes used in this are analysed to identify improvement potential. Shortcomings are identified in three main areas: safety assurance, design process integration and financial optimisation. Better design process integration is required because data is not readily exchanged between the industry standard software tools. There is also a lack of clarity about how to optimise design decisions with respect to factors such as shading and cable size. Financial optimisation is identified as a challenge because current software tools facilitate optimising for maximum output or minimum cost, but do not readily optimise for minimum levelised cost of energy which is the primary objective in striving for grid parity. To achieve improved design process integration and financial optimisation, a new modelling framework with the working title SolaSIM is conceived to accurately model the performance of solar photovoltaic systems. This framework is developed for grid connected systems operating in the UK climate, but it could readily be adapted for other climates with appropriate weather data. This software development was conducted using an overarching systems engineering approach from design and architecture through to verification and validation. Within this SolaSIM framework, the impact of shading on array and inverter efficiency is identified as a significant area of uncertainty. A novel method for the calculation of shaded irradiance on each cell of an array with high computational efficiency is presented. The shading sub-model is validated against outdoor measurements with a modelling accuracy within one percent. Final verification of the over-arching SolaSIM framework found that it satisfied the requirements which were identified and actioned. The author installed the new CREST outdoor measurement system version 4 (COMS4). COMS4 is a calibrated system which measures 26 PV devices simultaneously. Validation of SolaSIM models against COMS4 found the modelling error to be within the 4% accuracy target except two sub-systems which had electronic faults. The model is validated against PV systems and found to be within the specified limits.
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Franklin, Edward. "Hand Tools Used for Solar Photovoltaic (PV) Systems". College of Agriculture, University of Arizona (Tucson, AZ), 2017. http://hdl.handle.net/10150/625442.
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5 p.A description of the multiple hand tools commonly used to measure energy output of solar photovoltaic (PV) silicon-type modules. These tools include a digital multi-meter to measure voltage, a clamp-on ammeter to measure current, a pyranometer to measure solar irradience, an angle finder to measure module tilt angle, a non-contact thermometer to measure solar cell temperature, and a Solar Pathfinder to evaluate a potential site for shading issues.
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BERNARDONI, Paolo. "Performance Optimization of Luminescent Solar Concentrator Photovoltaic Systems". Doctoral thesis, Università degli studi di Ferrara, 2016. http://hdl.handle.net/11392/2403385.
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Lo scopo di questo lavoro è l'ottimizzazione di sistemi fotovoltaici basati su concentratori solari a luminescenza, questi dispositivi non sono di nuova concezione ma, al momento, non è ancora disponibile un'analisi approfondita di sistemi dalle dimensioni adatte alla costruzione di dispositivi per integrazione architettonica. Per questa ragione, in questo lavoro, vengono analizzate le prestazioni di LSC costruiti impiegando diversi pigmenti, dimensioni e configurazioni ottiche così come l'effetto dell'auto-assorbimento sullo spettro di emissione del dispositivo, inoltre le differenti configurazioni ottiche sono state anche sottoposte a diverse condizioni di ombreggiamento così da identificare la più efficiente non solo in condizioni di lavoro ideali ma anche in uno scenario più simile alle reali condizioni di impiego di un dispositivo mirato all'integrazione architettonica. I prototipi sono stati costruiti a seguito di un ampio lavoro di simulazione del loro comportamento ottico mirato alla selezione delle configurazioni più promettenti, in particolare non è stata tenuta in considerazione solo l'efficienza ma anche la scalabilità del progetto e la facilità di assemblaggio: caratteristiche importanti per un prototipo che dovrebbe essere oggetto di trasferimento tecnologico dalla ricerca all'industria. Il primo risultato ottenuto è la dimostrazione della fattibilità di LSC di grandi dimensioni, ben oltre la comune dimensione da laboratorio di 5x5cm, inoltre, si è anche dimostrato come le prestazioni degli LSC possano essere incrementate con una contemporanea riduzione dei costi applicando pellicole riflettenti sui bordi così da uniformare il profilo di irradianza sulle celle. Tuttavia il risultato più significativo ottenuto è di aver dimostrato come sistemi con un ridotto numero di celle accoppiate a pellicole riflettenti poste sui lati rimanenti dell'LSC possano fornire un'efficienza maggiore rispetto ai sistemi tradizionali con le celle posizionate su quattro lati. Questi sistemi hanno anche mostrato una minore sensibilità agli effetti dell'ombreggiamento che rappresenta un risultato fondamentale per una tecnologia mirata all'integrazione architettonica, sottolineandone il progresso da argomento di ricerca a tecnologia con buone premesse di trasferimento verso l'industria.The purpose of this work is the optimization of photovoltaic systems based on luminescent solar concentrators, these devices are not a new concept but, so far, a thorough analysis of the performance of LSC systems with sizes practical for building integration applications is missing. For this reason in this work the performances of LSCs based on different dyes, different sizes and various optical configurations were analysed as well as the effect of self-absorption on the output spectrum, moreover the performances of the systems with different optical configurations were analysed under some possible shading conditions in order to identify the most efficient and convenient design non only under an ideal working exposure but also in a real world scenario. The prototypes were built after an extensive work of simulation of their optical behaviour aimed at selecting the most promising designs, in particular not only the efficiency has been taken into account but also the scalability of the modules to larger or smaller sizes and the ease of assembly: important features for a design that should undergo a technology transfer from research to industrialization. The first result obtained is that the feasibility of large size LSCs (up to one square metre) well above the common laboratory size of 5×5cm have been demonstrated, moreover, it has also been shown that the performances of LSC systems can be improved, while lowering cost at the same time, by using reflective layers to get a more uniform irradiance profile on the cells. Anyway the most remarkable result obtained so far is having demonstrated that systems employing a small number of cells and a reflective film on the remaining sides of the LSC can yield a higher efficiency than a traditional design with cells placed on four sides, moreover these systems have also demonstrated a lower sensitivity to shading losses which represents a fundamental result for a technology targeted at the building integration, highlighting the progress of luminescent solar concentrators from a mere laboratory research topic to a promising industrialisable technology.
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Coventry, Joseph Sydney. "A solar concentrating photovoltaic/thermal collector /". View thesis entry in Australian Digital Theses Program, 2004. http://thesis.anu.edu.au/public/adt-ANU20041019.152046/index.html.
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Ropp, Michael Eugene. "Design issues for grid-connected photovoltaic systems". Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/13456.
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Wakter, Simon, i Fredrik Wikerman. "A novel shade analysis technique for solar photovoltaic systems". Thesis, KTH, Energiteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-148122.
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Solar power is a rapidly growing energy source. As efficiency increases and costs decrease, solar photovoltaic (PV) systems are becoming increasingly attractive for small and medium scale consumers to invest in. Despite advancements in photovoltaic technology, minor shading will still drastically reduce the performance of a solar cell module. Therefore, shade analysis should be performed before installation in order to assess the financial viability of an investment as well as to optimize the location and orientation of a photovoltaic module. The process of accurate shade analysis however, is something that is currently only carried out by professionals using expensive equipment. This bachelor’s thesis aims to develop the concept of a smartphone based shade analysis technique, which by using MATLAB’s predefined image processing should produce a shading diagram together with data ready for use as input in PV simulation software. The results should be comparable to those of professional shading analysis products. As a result, the concept of a shading analysis technique based on panoramic image capturing using a smartphone and MATLAB image processing has been shown to work. The final analysis technique uses a smartphone captured panoramic image as input and provides two forms of output: A shading diagram for easy and quick overview, providing information about which obstacles may cause shading at a specific time of day and year An excel file that can be used as input in the PV simulation software System Advisor Model (SAM)Solenergi är en snabbt växande energikälla. Allteftersom effektiviteten ökar och kostnaden minskar, blir solcellssystem allt mer attraktivt för små och medelstora konsumenter att investera i. Trots framsteg inom solcellsteknik, fortsätter även mindre skuggning att ge upphov till stora effektbortfall i solcellsmoduler. Därför utförs ofta skugganalys före installation, för att bedöma investeringens ekonomiska lönsamhet, likväl som för att optimera placeringen av solcellsmodulen. För närvarande är dock precis skugganalys något som endast utförs av yrkesverksamma med hjälp av dyr specialutrustning. Detta kandidatexamensarbete syftar till att utveckla ett koncept kring en smartphone-baserad skugganalysteknik som med MATLABs fördefinierade digitala bildbehandling ska producera ett skuggdiagram tillsammans med data som kan användas i PV-simuleringsverktyg. Resultaten ska vara jämförbara med resultat från professionella produkter för skugganalys Efter projektets genomförande kan det konstateras att konceptet med en skugganalysteknik baserad på MATLABs bildbehandling och en panoramabild som tagits med en smartphone fungerar. Den slutliga analystekniken använder sig av en panorama bild som indata och ger utdata i två former Ett skuggdiagram för enkel och snabb överblick, vilket ger information om vilka hinder som skulle kunna orsaka skugga vid specifik tid En excel-fil som kan användas som indata i PV-simuleringsprogrammet System Advisor Model (SAM)
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Alrashidi, Abdulla. "Investigating the feasibility of solar photovoltaic systems in Kuwait". Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/27657.
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This thesis presents work undertaken to investigate the feasibility of implementing solar photovoltaic (PV) systems in Kuwait. Performance parameters, environmental, and economic evaluations and assessments, as well as a numerical modelling study, were conducted as the main investigative elements to help judge the feasibility. The effect of using single-axis and dual-axis tracking systems was also considered. An assessment of the performance parameters of the proposed PV systems at selected locations in Kuwait was conducted on a monthly basis, using different tracking systems to compare the sites. Moreover, an annual basis analysis was carried out to compare the obtained results with those of different studies in the existing literature. An environmental assessment was conducted in the form of a Life Cycle Assessment (LCA), estimating the levels of greenhouse gas (GHG) emissions that could be avoided. An economic assessment of implementing the proposed PV systems at the selected locations, and a cost-benefit analysis were conducted. In addition, modelling of a two-axis solar tracker was performed to ensure the stability and reliability of the proposed solar tracker in Kuwait. This was done using a 3D finite element model to examine the soil-structure interaction using COMSOL Multiphysics software.
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Guarracino, Ilaria. "Hybrid photovoltaic and solar thermal (PVT) systems for solar combined heat and power". Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/58172.
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Solar is a particularly promising sustainable energy source in terms of its potential to displace the burning of fossil fuels for heat and power, heating and even cooling, albeit at a cost. The sun load-factor profile has a close and predictable match to the daily varying energy demand for heat and electricity, both thermal and electrical, and thermal storage for periods of low irradiance can be made readily available. In addition, solar thermal technologies can provide a significant fraction of the hot water demand in households, as well as space heating and cooling in residential buildings and for industrial facilities. In fact, solar heating has been proposed as one of the leading solutions in terms of its potential for greenhouse gas abatement [1]. At the small scale, photovoltaic systems presently dominate the domestic solar market with solar to electrical conversion efficiencies of around 15% and at a competitive cost for the building owner. Solar photovoltaic installations were encouraged in Europe at the local level with financial support and now constitute a large and mature market with continuously falling prices. Solar thermal systems are able to make use of a larger proportion of the solar resource as they convert solar energy into heat with a higher efficiency than the PV conversion efficiency. Moreover, the low temperature heat may be used to satisfying the largest portion of the demand for thermal energy that is currently met by fossil fuels. The development of the solar thermal market is strongly dependent on the availability of the local irradiance level and on the cost of the alternative sources of thermal energy. In some countries in Europe the solar thermal market is quite mature (e.g. Austria), whilst in others, such as in the UK, solar thermal energy still contributes marginally to the energy mix and solar thermal systems are not yet cost competitive. Due to the high costs of solar thermal energy systems, these constitute a relatively small market at present with the potential to grow substantially in the near future. A competitive solution for energy (heat and power) provision in buildings is the development of combined solar photovoltaic/thermal (PVT) systems which produce both electricity and heat simultaneously from the same aperture area. This solution is particularly suited to residential applications in urban areas, where the demand for electricity is accompanied by a demand for low temperature heat, and space for solar installations is scarce. Many alternative technologies for PVT integration exist and PVT units can be coupled with various systems for domestic hot water generation and/or space heating. At the design stage of a PVT system, decisions have to be made on the absorber characteristics (consisting of thermal collector and PV laminate), on the thermal to electrical yield ratio and on the application (industrial or residential application, stand alone or grid connected). These design parameters influence the requirements on the fluid temperature and electricity output, and the overall efficiency. In addition, system control can significantly impact the potential of such systems in terms of their performance characteristics in different applications. The aim of this present research effort was to demonstrate the technical and practical feasibility of a novel, high-efficiency hybrid PVT water system, by considering an affordable, small-scale, modular unit that can be scaled easily to cater to varying demand levels. The research investigated the technical issues related to PVT panel technology, by looking in particular at the optical efficiency of the PV cells, at the heat transfer from the PV cells to the fluid, and at the integration of such a unit in a heat and power provision system that attempts to match generation and local demand. A detailed numerical model was developed that constitutes a tool for testing various collector and system designs. The model was validated against experimental data. An experimental apparatus was designed and constructed for the purpose of evaluating the collector model and for collecting a database of performance data on PVT collectors. Collector performance data are scarce at the moment due to the relatively small market size, thus the work constitutes a reference for further development and analysis of this type of collectors. Steady-state tests and dynamic tests were performed on PVT collectors and the results were used to develop a reliable model of collector performance over a wide range of time-varying operating conditions. The model allowed for assessments of various solar PVT system designs under different operating conditions and control strategies. Result showed that such systems may underperform if their operation and design is not designed specifically for the local weather conditions and user-demand specific requirements. It is envisaged that emissivity control applied to the solar cells should be adopted for PVT system application, especially if higher operating temperatures are required (e.g. in combination with thermally driven/heat powered cooling systems). The numerical model confirms that solar cells a with low emissivity coating can maximise the thermal energy output of a PVT system. The potential of improved PVT systems is finally assessed from an economic perspective, in an analysis that considers the potential cost reduction of PVT systems in relation to alternative technologies used as a benchmark.
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Umana, Aniemi. "Module-level autonomous settingless protection and monitoring for standalone and grid-connected photovoltaic array systems using quadratic integration modeling". Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54441.
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This research applies a recently developed dynamic state-estimation based protection scheme, the settingless protection, to the photovoltaic (PV) industry for the first time. At this time, the proposed protection algorithm has been implemented on traditional protection zones for individual power system devices, but this research extends this protection to a microgrid, specifically, a system of PV network composed of several PV modules. Several illustrative examples on various anomalies such as high impedance faults and shorted-out PV modules have been provided to demonstrate the effectiveness of this protection scheme. The detection of these anomalies has been demonstrated in the presence of changing atmospheric conditions, and with the operation of maximum power point tracking (MPPT) equipped dc-dc converters.
This protection scheme requires an accurate model of the PV module, therefore, a two-diode PV model has been developed using quadratic integration modeling. In this PV model development, a scaling factor is applied to the Taylor series expansion of the exponential terms of the model of the PV module. Then the higher order terms of the Taylor series expansion are reduced to at most second order terms using the quadratization technique.
Furthermore, a novel approach for extracting the PV parameters, namely, the ideality constants, leakage currents, PV module internal current, shunt and series resistances, has been presented. A comparison was performed between numerically generated data using the determined PV module parameters and data measurements from a physical PV module. It was shown that the maximum error from this comparison was below 0.12A, and less than 0.05A around the maximum power point region of the PV modules used for this research.
The residual data from the PV array protection scheme has been used to develop a method for identifying the location of faulted PV modules. Also, condition-based monitoring of the PV array system has also been presented with examples. From the PV array system monitoring, the shading and underperformance of a PV module have been identified.
From the contributions of this research, an accurate module of the PV array has been developed in a form that can be integrated with other power system devices. This accurate module can be used for state estimation of the PV array, load flow analysis, short circuit analysis, and other power system analytical studies. Also, by determining the location of the faulted PV module, the time to identify this faulted PV module in a large PV installation is drastically reduced. Lastly, by identifying shading conditions and underperforming PV modules, the PV system operator can quickly bring the underperforming module or modules to optimal performance, thereby, maximizing the power yield of the PV array, and maximizing the revenue of the PV system owner.
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Mehrtash, Mostafa. "Performance evaluation of solar tracking photovoltaic systems operating in Canada". Mémoire, École de technologie supérieure, 2013. http://espace.etsmtl.ca/1138/1/MEHRTASH_Mostafa.pdf.
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En 2011, la capacité totale installée du Photovoltaïque au Canada était de 289 MW et elle pourrait atteindre entre 9 et 15 GW d'ici 2025. Selon des études antérieures, des systèmes de suivi solaires PV peuvent capturer 20% à 50% plus de rayonnement solaire que les systèmes fixes. Un suiveur solaire est un dispositif qui maintient les panneaux photovoltaïques perpendiculaires aux rayons du soleil. Il y a un manque de connaissances sur la performance des systèmes solaires photovoltaïques de suivi d'exploitation dans les conditions météorologiques sévères du Canada.
Trois objectifs principaux ont été définis pour cette recherche. Le premier objectif est l'évaluation des performances en fonction de la stratégie de suivi pour les systèmes PV. Cet objectif est atteint par la simulation et l'analyse de quatre systèmes PV: horizontal fixe, incliné fixe, suivi selon un axe et suivi selon deux axes. Ces systèmes sont analysés au cours des périodes annuelles, mensuelles et journalières. Quatre villes avec des conditions météorologiques différentes ont été étudiées: Montréal (Canada), Casablanca (Maroc), Ouagadougou (Burkina Faso), et Olympia (USA). Les résultats obtenus à partir de simulations montrent que les systèmes de suivi selon deux axes présentent les rendements les plus élevés dans tous les endroits choisis.
Le deuxième objectif est de déterminer l'orientation optimale d'un système d'exploitation PV dans des conditions climatiques du Canada. Cet objectif est atteint en enquêtant sur la météo et les conditions environnementales du Canada qui touchent les systèmes PV, y compris les basses températures en hiver et le rayonnement réfléchi par la neige (effet albédo). Le rayonnement réfléchi par la neige cumulée sur le sol entraîne une augmentation de l'irradiation des panneaux jusqu'à 4,1%, 5,6% et 6,9% pour les systèmes inclinées, avec suivi selon un axe, et avec suivi selon deux axes pendant l'hiver, respectivement. Les systèmes de suivis selon un axe et deux axes reçoivent 28% et 33% de plus de rayonnement solaire que le système incliné sur un an. De plus, le suivi du soleil pourrait précipiter le phénomène de fusion de la glace et de la neige accumulée sur les panneaux photovoltaïques.
L'objectif final de cette thèse est le choix de la méthode de suivi optimale pour le Canada. Cet objectif est atteint par l'analyse de diverses orientations des systèmes PV dans les jours typiques: une journée d'hiver claire, une claire journée d'été, et une journée nuageuse d’hiver et d’été.
Selon les analyses quotidiennes, le suivi du soleil est efficace les jours de soleil direct (clairs), contre-productif les jours nuageux, et dépend de l'indice de clarté dans les jours très nuageux. Ces résultats sont corroborés par des recherches antérieures. Les résultats permettent de proposer une méthode qui permet de suivre le soleil dans des conditions claires et d’aller à la position horizontale dans des conditions nuageuses. En conditions nuageuses partielles, la stratégie de suivi à adopter dépend de l'indice de clarté et de rayonnement réfléchi par le sol.
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Levy, Michael Yehuda. "Design, experiment, and analysis of a photovoltaic absorbing medium with intermediate levels". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24703.
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Thesis (Ph.D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008.Committee Chair: Honsberg, Christiana; Committee Co-Chair: Citrin, David; Committee Member: Doolittle, Alan; Committee Member: First, Phillip; Committee Member: Ralph, Stephen; Committee Member: Rohatgi, Ajeet
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Njouakoua, Tchonko Leon. "Reconfigurable photovoltaic modules for robust nanosatellite power systems". Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2620.
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Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2018.Until recently, the focus of most solar technology development for space was towards more efficient, more radiation-resistant and increasingly powerful arrays. During a space mission, solar cells are not only exposed to irradiation by electrons, but also to a range of other particles, like protons. Thus, solar cells on robust nanosatellites are extremely exposed to an environment, which includes the high-energy electrons and protons of the earth’s radiation belts, which leads towards the degradation process of the individual solar cell. Solar cell radiation shielding design ensures the protection of the solar cells from the particular radiation environment found in space. While the design principles of a solar photovoltaic automatic switching fault tolerant system which can detect and bypass faulty photovoltaic cells will be presented through this research work. The ability of such a system to be reconfigured using implemented switching matrix system makes it efficient under various environments and faulty conditions.
National Research Foundation (NRF)
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Leyte-Vidal, Albert. "ESTABLISHING DEGRADATION RATES AND SERVICE LIFETIME OF PHOTOVOLTAIC SYSTEMS". Master's thesis, University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3001.
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As fossil fuel sources continue to diminish, oil prices continue to increase, and global warming and CO2 emissions keep impacting the environment, it has been necessary to shift energy consumption and generation to a different path. Solar energy has proven to be one of the most promising sources of renewable energy because it is environmentally friendly, available anywhere in the world, and cost competitive. For photovoltaic (PV) system engineers, designing a PV system is not an easy task. Research demonstrates that different PV technologies behave differently under certain conditions; therefore energy production varies not only with capacity of the system but also with the type of module. For years, researchers have also studied how these different technologies perform for long periods of time, when exposed out in the field. In this study, data collected by the Florida Solar Energy Center for periods of over four years was analyzed using two techniques, widely accepted by researchers and industry, to evaluate the long‐term performance of five systems. The performance ratio analysis normalizes system capacity and enables the comparison of performance between multiple systems. In PVUSA Regression analysis, regression coefficients are calculated which correspond to the effect of irradiance, wind speed, and ambient temperature, and these coefficients are then used to calculate power at a predetermined set of conditions. This study allows manufacturers to address the difficulties found on system lifetime when their modules are installed out on the field. Also allows for the further development and improvement of the different PV technologies already commercially available.M.S.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering MSEE
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Gow, John A. "Modelling, simulation and control of photovoltaic converter systems". Thesis, Loughborough University, 1998. https://dspace.lboro.ac.uk/2134/6871.
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The thesis follows the development of an advanced solar photovoltaic power conversion system from first principles. It is divided into five parts. The first section shows the development of a circuit-based simulation model of a photovoltaic (PV) cell within the 'SABER' simulator environment. Although simulation models for photovoltaic cells are available these are usually application specific, mathematically intensive and not suited to the development of power electronics. The model derived within the thesis is a circuit-based model that makes use of a series of current/voltage data sets taken from an actual cell in order to define the relationships between the cell double-exponential model parameters and the environmental parameters of temperature and irradiance. Resulting expressions define a 'black box' model, and the power electronics designer may simply specify values of temperature and irradiance to the model, and the simulated electrical connections to the cell provide the appropriate I/V characteristic. The second section deals with the development of a simulation model of an advanced PVaware DC-DC converter system. This differs from the conventional in that by using an embedded maximum power tracking system within a conventional linear feedback control arrangement it addresses the problem of loads which may not require the level of power available at the maximum power point, but is also able to drive loads which consistently require a maximum power feed such as a grid-coupled inverter. The third section details a low-power implementation of the above system in hardware. This shows the viability of the new, fast embedded maximum power tracking system and also the advantages of the system in terms of speed and response time over conventional systems. The fourth section builds upon the simulation model developed in the second section by adding an inverter allowing AC loads (including a utility) to be driven. The complete system is simulated and a set of results obtained showing that the system is a usable one. The final section describes the construction and analysis of a complete system in hardware (c. 500W) and identifies the suitability of the system to appropriate applications.
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Riverola, Lacasta Alberto. "Dielectric solar concentrators for building integration of hybrid photovoltaic-thermal systems". Doctoral thesis, Universitat de Lleida, 2018. http://hdl.handle.net/10803/663116.
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L'objectiu de la present tesi és desenvolupar, optimitzar, fabricar i caracteritzar experimentalment un sistema solar de baixa concentració, fotovoltaic i tèrmic, per a integració arquitectònica en façanes on les cèl·lules estan submergides en un líquid dielèctric. L'objectiu està alineat cap al compliment de la directiva sobre eficiència energètica en edificis establerta per la Comissió Europea.
Els sistemes solars fotovoltaics i tèrmics per integració en edificis permeten la cogeneració d'electricitat i calor al mateix edifici amb unes eficiències globals al voltant del 70% i utilitzen una menor superfície comparat amb un col·lector tèrmic i un mòdul fotovoltaic independents. D'altra banda, els sistemes de baixa concentració permeten reduir costos utilitzant cèl·lules solars estàndards, amb una àrea reduïda i seguiment en un sol eix. A més, la immersió de les cèl·lules en líquids dielèctrics comporta uns beneficis agregats com ara la reducció de les pèrdues de Fresnel i un millor control de la temperatura. La necessitat d'estudiar i desenvolupar aquests sistemes per a la seva integració en edificis ve donada per les qualitats prèviament descrites i per l’estudi de l'estat de l'art realitzat.
El disseny proposat està compost d'un xassís cilíndric i una cavitat interna per on circula el líquid dielèctric (aigua desionitzada o alcohol isopropílic) en el qual hi ha les cèl·lules submergides. Cada mòdul segueix l'altura solar rotant i està dissenyat per ser col·locat en files formant una matriu. L'aparença del conjunt és similar a la de les lames que es troben normalment en les finestres. S’ha implementat un moviment secundari que controla la distància vertical entre mòduls per evitar l’ombra entre ells mateixos i controla la il·luminació interior.
Per dur a terme un desenvolupament òptim, s'ha modelat la distribució espectral de la llum solar incident a la qual es veuen exposades les cèl·lules solars en condicions reals. S’ha dut a terme un anàlisis exhaustiu dels líquids dielèctrics susceptibles de complir amb els requeriments per a la present aplicació. S'ha modelat la absortivitat / emissivitat de les cèl·lules de silici comercials en un rang espectral que va des del ultraviolat fins a l'infraroig mitjà i s'ha validat experimentalment. A partir d'aquí, s’ha desenvolupat un algoritme de traçat de raigs que computa l'energia per optimitzar el disseny òptic del concentrador per posteriorment fabricar-lo i analitzar-lo mitjançant una simulació CFD. Fet que ens permet caracteritzar el sistema tèrmicament i òpticament. Finalment, s'ha realitzat una simulació energètica amb el sistema instal·lat a les finestres d'una casa estàndard per tal d'avaluar quines parts de les demandes energètiques de l'edifici és capaç de satisfer. Aquesta simulació s’ha dut a terme en tres localitzacions diferents.
El rendiment del sistema ha estat estudiat en llocs caracteritzats per hiverns suaus i altures solars no molt elevades, obtenint resultats satisfactoris cobrint una gran part de la demanda de climatització, d'aigua calenta sanitària i elèctrica.El objetivo de la presente tesis es desarrollar, optimizar, fabricar y caracterizar experimentalmente un sistema solar de baja concentración, fotovoltaico y térmico, para integración arquitectónica en fachadas donde las células están sumergidas en un líquido dieléctrico. Este objetivo está perfectamente alineado con el cumplimiento de la directiva sobre eficiencia energética en edificios establecida por la Comisión Europea. Los sistemas solares fotovoltaicos y térmicos para integración en edificios atesoran la cogeneración de electricidad y calor en el mismo edificio con unas eficiencias globales alrededor del 70% y utilizando una menor superficie que si incorporamos un colector térmico y un módulo fotovoltaico separados. Por otra parte, los sistemas de baja concentración permiten reducir costes utilizando células solares estándar, con un área reducida y seguimiento en un solo eje. Además, la inmersión de las células en líquidos dieléctricos conlleva unos beneficios agregados como son la reducción de las pérdidas de Fresnel y un mejor control de la temperatura. Del estado del arte realizado y las cualidades previamente descritas, se desprende la necesidad de estudiar y desarrollar estos sistemas para su integración en edificios. El diseño propuesto está compuesto de un chasis cilíndrico y una cavidad interna por donde circula el líquido dieléctrico (agua desionizada o alcohol isopropílico) en el cual están las células sumergidas. Cada módulo sigue la altura solar rotando y está diseñado para ser colocado en filas formando una matriz. De este modo, la apariencia del conjunto es similar a la de las lamas que se encuentran comúnmente en ventanas. Además, un movimiento secundario que regula la distancia vertical entre los módulos para evitar sombreo entre ellos mismos y controlar la iluminación interior, ha sido implementado. Para llevar a cabo un desarrollo óptimo, se ha modelado la distribución espectral de la luz solar incidente a la cual se ven expuestas las células solares en condiciones reales. Se ha realizado un análisis exhaustivo de los líquidos dieléctricos susceptibles de cumplir con los requerimientos para la presente aplicación. Se ha modelado la absortividad/emisividad de las células de silicio comerciales en un rango espectral que va desde el ultravioleta hasta el infrarrojo medio y se ha validado experimentalmente. A partir de aquí, se ha desarrollado un algoritmo de trazado de rayos para optimizar el diseño óptico del concentrador con el fin de posteriormente fabricarlo y analizarlo mediante una simulación CFD. Hecho que nos permite caracterizarlo ópticamente y térmicamente. Finalmente, se ha realizado una simulación energética con el sistema instalado sobre las ventanas de una casa estándar para evaluar que parte de las demandas energéticas del edificio es capaz de satisfacer. Esta simulación se ha realizado en tres localizaciones distintas. El rendimiento del sistema ha sido estudiado en lugares caracterizados por inviernos suaves y alturas solares no muy elevadas, cubriéndose una gran parte de las demandas de agua caliente sanitaria, eléctricas y de climatización.
The goal of this thesis is to develop, optimize, fabricate and experimentally test a low-concentrating photovoltaic thermal system (CPVT) for building façade integration where the cells are directly immersed in a dielectric liquid. The objective sought is perfectly aligned with the Energy Performance Building Directive established by the European Commission in terms of energy efficiency. Building-integrated PVT systems present an on-site cogeneration of electricity and heat with global efficiencies around 70% and lower space utilization compared to a separate thermal collector and PV module. On the other hand, low-concentrating systems improve the cost effectiveness by using standard cells, single axis-tracking and reduced cell areas. In addition, direct-immersion of solar cells in dielectric liquids brings associated benefits such as a reduction of Fresnel losses and a better temperature control. From the state-of-the-art performed and the previous facts, the need for further developing and studying these systems for building integration purposes was found. The proposed design is composed by a cylindrical chassis and an inner cavity filled with the circulating dielectric liquid (deionized water or isopropyl alcohol) in which the cells are immersed. The module tracks the solar height by rotation and it is designed to be placed in rows as an array so that the appearance is akin to ordinary window blinds. A secondary movement has been implemented to control the vertical distance between modules and to avoid shading between them while provide lighting control. For an appropriate development, the spectral distribution of the incident solar irradiance to which solar cells are exposed under real working conditions has been modelled. An in-depth analysis of suitable dielectric liquid candidates based on the required properties for this application has been performed. The absorptivity/emissivity of standard silicon solar cells has been modeled from the ultraviolet to the mid-infrared and validated by an experimental measurement. Then, a full ray-tracing algorithm was developed to optimize the concentrator optical design and the optimum collector was fabricated and analyzed by a CFD simulation to thermally characterize the system. Finally, an energetic simulation with the concentrators superimposed in front of the windows in a standard house aiming to partially cover the building demands has been performed for three locations. The system performance has been studied for locations with mild winters and latitudes not achieving very high solar heights with satisfactory solar fractions regarding domestic hot water, electrical and space heating and cooling demands.
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Elsaidi, Abdulsalam. "Photovoltaic (PV) type solar generators and their effect on distribution systems". Thesis, University of Missouri - Kansas City, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1544928.
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Distribution systems are designed to operate in radial mode (the simplest system topology) without any generation on the system, unidirectional power flow from the distribution substation to the customers via main feeder(s) and its(their) laterals within a specified range of operating points. The rapid growth of PV module installations on the distribution systems could not only offset the load but also cause a significant impact on the flow of power (active and reactive), voltage level, and fault currents, therefore; concerns about their potential impacts on the stability and operation of the power system have become one of the important issues and may create barriers to their future expansion. The most likely potential impact of the high PV penetration level is losing the voltage regulation, because it is directly related to the amount of reverse power flow. The main goal of this thesis is to approximate the maximum level of PV penetration which the system can accommodate without any impact on the voltage profile, stability, and operation.
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Allan, James. "The development and characterisation of enhanced hybrid solar photovoltaic thermal systems". Thesis, Brunel University, 2015. http://bura.brunel.ac.uk/handle/2438/11624.
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A photovoltaic thermal solar collector (PVT) produces both heat and electricity from a single panel. PVT collectors produce more energy, for a given area, than conventional electricity and heat producing panels, which means they are a promising technology for applications with limited space, such as building integration. This work has been broken down into 3 subprojects focusing on the development of PVT technology. In the first subproject an experimental testing facility was constructed to characterise the performance of PVT collectors. The collectors under investigation were assembled by combining bespoke thermal absorbers and PV laminates. Of the two designs tested, the serpentine design had the highest combined efficiency of 61% with an 8% electrical fraction. The header riser design had a combined efficiency of 59% with an electrical fraction of 8%. This was in agreement with other results published in literature and highlights the potential for manufacturers of bespoke thermal absorbers and PV devices to combine their products into a single PVT device that could achieve improved efficiency over a given roof area. In the second project a numerical approach using computational fluid dynamics was developed to simulate the performance of a solar thermal collector. Thermal efficiency curves were simulated and the heat removal factor and heat loss coefficient differed from the experimental measurements by a maximum of 12.1% and 2.9% respectively. The discrepancies in the findings is attributed to uncertainty in the degree of thermal contact between the absorber and the piping. Despite not perfectly matching the experimental results, the CFD approach also served as a useful tool to carry out performance comparisons of different collector designs and flow conditions. The effect of 5 different flow configurations for a header collector was investigated. It was found that the most efficient design had uniform flow through the pipe work which was in agreement with other studies. The temperature induced voltage mismatch, that occurs in the PV cells of PVT collector was also investigated. It was concluded that the temperature variation was not limiting and the way in which PV cells are wired together on the surface of a PVT collector did not influence the combined electrical power output.
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Pappu, Venkata Ajay Kumar. "Implementing frequency regulation capability in a solar photovoltaic power plant". Diss., Rolla, Mo. : Missouri University of Science and Technology, 2010. http://scholarsmine.mst.edu/thesis/pdf/Pappu_09007dcc807d51ca.pdf.
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Thesis (M.S.)--Missouri University of Science and Technology, 2010.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed July 19, 2010) Includes bibliographical references (p. 88-90).
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Sun, Li. "Implementations of electric vehicle system based on solar energy in Singapore : assessment of solar photovoltaic systems". Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/54563.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2009.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 150-156).
To evaluate the feasibility of solar energy based Electric Vehicle Transportation System in Singapore, the state of the art Photovoltaic Systems have been reviewed in this report with a focus on solar cell technologies. Various solar cell technologies were evaluated based on characteristics such as efficiency, reliability and cost to identify a best working one under Singapore's hot and humid climate. Commercial CdTe modules were found to have the best efficiency to cost ratio, making them the best module choice in land-scarce and tropical Singapore. Based on the market price and characteristics of CdTe modules from manufacturer First Solar Ltd, two PV systems based on an apartment model and a private house model were evaluated. The cost of electricity from a relatively large scale grid-tied PV system is found to be at around US$0.173/kWh which is not market competitive with the utility electricity price of US$0.109/kWh in Singapore. But with enough capital funding and government incentives such as rebate or feed-in price tariff, PV electricity generation could become economically feasible. The small private house system is found not economical as a means of household electricity generation even with current status of government rebate. When carbon trading is considered, the current trading price has to be increased by around 7 times of the current value or 3 times of the predicted price at 2016 to offset the difference with the utility electricity price.
by Li Sun.
M.Eng.
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CORONA, FABIO. "Building Integrated Photovoltaic Systems: specific non-idealities from solar cell to grid". Doctoral thesis, Politecnico di Torino, 2014. http://hdl.handle.net/11583/2538891.
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After an initial phase of great diffusion of large Photovoltaic (PV) systems installed on the ground, the recent evolution of the feed-in tariffs makes the Building
Integrated PV (BIPV) systems for residential, commercial and industrial users, the more befitting application of the PV technology.
Unfortunately, the building integration implies some critical issues on the operation of principal components, such as the PV panels or the grid-connected inverter, typical of this kind of installation and not so important in the case of ground mounted PV plants. These non-idealities can be due to: presence of obstacles near the PV panels, like trees, poles, antennas, architectural elements (chimneys, barriers, buildings in the neighbourhood); non-optimal orientation of the PV field (not Southward) or with different orientations among the sub-fields,
with consequent production asymmetry between morning and evening or mismatch; sub-optimal tilt angle of the PV modules, as it is fixed by the building roof; not-efficient cooling of the PV panels, which can cause temperature gradients both horizontally, between PV modules in the central area of the field and the peripheral ones, and vertically, between panels installed in the bottom and in the top of a structure, due to the direction of the cooler flow.
The consequences of these non-idealities is the subject of this PhD dissertation, from both theoretical, through convenient simulation tools, and experimental viewpoints. The most evident of these effects is the mismatch of the currentvoltage characteristics of the PV field panels. With the aim of illustrating the analysis methodologies used to study the mismatch effect on all the PV system components, a specific case study is considered, constituted by a large BIPV system (almost 1MWp) installed on the roof of a wholesale warehouse.
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Baig, Hasan. "Enhancing performance of building integrated concentrating photovoltaic systems". Thesis, University of Exeter, 2015. http://hdl.handle.net/10871/17301.
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Buildings both commercial and residential are the largest consumers of electricity. Integrating Photovoltaic technology in building architecture or Building Integrated Photovoltaics (BIPV) provides an effective means for meeting this huge energy demands and provides an energy hub at the place of its immediate requirement. However, this technology is challenged with problems like low efficiency and high cost. An effective way of improving the solar cell efficiency and reducing the cost of photovoltaic systems is either by reducing solar cell manufacturing cost or illuminating the solar cells with a higher light intensity than is naturally available by the use of optical concentrators which is also known as Concentrating Photovoltaic (CPV) technology. Integrating this technology in the architecture is referred as Building integrated Concentrating Photovoltaics (BICPV). This thesis presents a detailed performance analysis of different designs used as BICPV systems and proposes further advancements necessary for improving the system design and minimizing losses. The systems under study include a Dielectric Asymmetric Compound Parabolic Concentrator (DiACPC) designed for 2.8×, a three-dimensional Cross compound parabolic concentrator (3DCCPC) designed for 3.6× and a Square Elliptical Hyperbolic (SEH) concentrator designed for 6×. A detailed analysis procedure is presented showcasing the optical, electrical, thermal and overall analysis of these systems. A particular issue for CPV technology is the non-uniformity of the incident flux which tends to cause hot spots, current mismatch and reduce the overall efficiency of the system. Emphasis is placed on modelling the effects of non-uniformity while evaluating the performance of these systems. The optical analysis of the concentrators is carried out using ray tracing and finite element methods are employed to determine electrical and thermal performance of the system. Based on the optical analysis, the outgoing flux from the concentrators is predicted for different incident angles for each of the concentrators. A finite element model for the solar cell was developed to evaluate its electrical performance using the outputs obtained from the optical analysis. The model can also be applied for the optimization of the front grid pattern of Si Solar cells. The model is further coupled within the thermal analysis of the system, where the temperature of the solar cell is predicted under operating conditions and used to evaluate the overall performance under steady state conditions. During the analysis of the DiACPC it was found that the maximum cell temperature reached was 349.5 K under an incident solar radiation of 1000 W/m2. Results from the study carried on the 3DCCPC showed that a maximum cell temperature of 332 K is reached under normal incidence, this tends to bring down the overall power production by 14.6%. In the case of the SEH based system a maximum temperature of 319 K was observed on the solar cell surface under normal incidence. An average drop of 11.7% was found making the effective power ratio of the system 3.4. The non-uniformity introduced due to the concentrator profile causes hotspots in the BICPV system. The non-uniformity was found to reduce the efficiency of the solar cell in the range of 0.5-1 % in all the three studies. The overall performance can be improved by addressing losses occurring within different components of the system. It was found that optical losses occurred at the interface region formed due to the encapsulant spillage along the edges of the concentrator. Using a reflective film along the edge of the concentrating element was found to improve the optical efficiency of the system. Case studies highlighting the improvement are presented. A reflective film was attached along the interface region of the concentrator and the encapsulant. In the case of a DiACPC, an increase of 6% could be seen in the overall power production. Similar case study was performed for a 3DCCPC and a maximum of 6.7% was seen in the power output. To further improve the system performance a new design incorporating conjugate reflective-refractive device was evaluated. The device benefits from high optical efficiency due to the reflection and greater acceptance angle due to refraction. Finally, recommendations are made for development of a new generation of designs to be used in BiCPV applications. Efforts are made towards improving the overall performance and reducing the non-uniformity of the concentrated illumination.
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Huber, Lon Michael. "THE SOLAR INVESTMENT A FINANCIAL ANALYSIS OF RESIDENTIAL PHOTOVOLTAIC SYSTEMS IN ARIZONA". Thesis, The University of Arizona, 2009. http://hdl.handle.net/10150/192494.
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Bollinger, Joshua David. "Applications of solar energy to power stand-alone area and street lighting". Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.umr.edu/thesis/pdf/Joshua_Bollinger_Thesis_09007dcc8031b71d.pdf.
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Thesis (M.S.)--University of Missouri--Rolla, 2007.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed April 17, 2007) Includes bibliographical references (p. 88-91).
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Alam, Mohammad Saad. "Real-time maximum power tracking and robust load matching of a stand-alone photovoltaic system a dissertation presented to the faculty of the Graduate School, Tennessee Technological University /". Click to access online, 2009. http://proquest.umi.com/pqdweb?index=0&did=1756844361&SrchMode=1&sid=2&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1280170042&clientId=28564.
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Crozier, Jacqueline Louise. "Characterisation of performance limiting defects in photovoltaic devices using electroluminescence and related techniques". Thesis, Nelson Mandela Metropolitan University, 2015. http://hdl.handle.net/10948/11004.
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Solar cells allow the energy from the sun to be converted into electrical energy; this makes solar energy an environmentally friendly, sustainable alternative to fossil fuel energy sources. Solar cells are connected together in a photovoltaic (PV) module to provide the higher current, voltage and power outputs necessary for electrical applications. However, the performance of PV modules can limited by the degradation and defects. PV modules can be characterised using various opto-electronic techniques, each providing information about the performance of the module. The current-voltage (I-V) characteristic curve of a module being the most commonly used characterisation technique. The I-V curve is typically measured in outdoor, fully illuminated, conditions. This allows performance parameters such as short circuit current (ISC), open circuit voltage (VOC) and maximum power (PMAX) to be determined. However, it can be difficult to determine the root cause of the performance drop from the I-V curve alone. Electroluminescence (EL) is a module characterisation technique that allows defects and failures in PV modules to be successfully identified. This study investigates the characterisation of solar cells and photovoltaic modules using EL. EL occurs when a solar cell or module is forward biased and the injected electron-hole pairs recombine radiatively. The intensity of the emitted EL is related the applied voltage and the material properties. EL imaging is a useful characterisation technique in identifying module defects and failures. Defects such as micro-cracks, broken contact fingers and fractures are detected in EL images as well as material features such as grain boundaries. The common defects in crystalline silicon are catalogued and the possible causes are discussed. An experimental setup was developed in order to systematically take a high resolution EL image of every cell in the module and record the applied voltage and current. This produces a very detailed, clear, image of each cell with a pixel size in the micrometre range. This process is time consuming to acquire an EL image of an entire module so alternatively a different setup can be used and an EL image of a whole module can be captured in a single frame with an increased pixel size in the millimetre range. For EL imaging a silicon charge-coupled device (CCD) camera was used because it has very good spatial resolution however this sensor is only sensitive to wavelength in the range of 300-1200 nm. There is an overlap in wavelengths from about 900 to 1100 nm allowing the EL emitted from silicon solar cells to be detected. In conjunction with the high-resolution EL system an image processing program was developed to crop, adjust and align the images so only the relevant cell was included. This program also automatically detects certain defects that have a regular shape. Micro-cracks, broken fingers and striation rings are automatically identified. The program has an adjustable sensitivity to identify small or large defects. Defective cells are distinguished from undamaged cells by comparing the binary images to the ideal, undamaged cell. The current-voltage curves and the performance parameters of modules were compared with the EL images in order to discuss and identify power limiting defects. Features that remove significant portions of the cell from electrical contact such as micro-cracks are shown to have a larger effect of the performance of the module. Other features such as broken contact fingers, contact forming failures and striation rings do not significantly lower the performance of the module. Thus an understanding of how different features affect the module performance is important in order to correctly interpret the EL results. The intensity of the luminescence emitted is related to the applied voltage and the quantum efficiency of the cell material. The spectrum of the emitted luminescence was modelled and related to the recombination properties of the cell such as surface recombination velocity and minority carrier diffusion length/lifetime. In this study the emitted spectrum was modelled and the effects of recombination properties of the cell on the emitted spectrum were examined. The spectrum of the detected EL was modelled, dependent on the sensitivity of the camera, the transmission of the filters and the emitted photon flux. The integration of short-pass filters into the experimental setup in order to isolate short-wavelength luminescence was discussed. There is a proportional relationship between the intensity of the emitted EL and the local junction voltage. Resistive losses like series and shunt resistances lower the applied voltage and thus affect the EL image. The voltage dependence was assessed by comparing EL images taken at different applied biases. Analysis of the variation in EL intensity with voltage was successful in determining the origin of certain features in an EL image. Certain defects, those that are related to series resistance or shunting are highly voltage dependent. When a feature has little or no dependence on voltage then the defect could be in the laminate layers and not in the cell material. The results of this study allow for in-depth analysis of the defects found in PV modules using the high resolution EL imaging system and the image processing routine. The development of an image processing routine allows the interpretation of the EL image to be done automatically, resulting in a faster and more efficient process. By understanding the defects visible in the EL image, the test is more meaningful and allows the results to be used to predict module performance and potential failures.
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Sheikh, Nasir Jamil. "Assessment of Solar Photovoltaic Technologies Using Multiple Perspectives and Hierarchical Decision Modeling". PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/978.
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The objective of this research is to build a decision model for a comprehensive assessment of solar photovoltaic technologies using multiple perspectives. These perspectives include: social, technological, economic, environmental, and political (STEEP) with each perspective consisting of multiple criteria. Hierarchical decision modeling and expert judgment quantification are used to provide the relative ranking of the perspectives and criteria. Such modeling is effective in addressing technology evaluations with competing and contrasting perspectives and criteria where both quantitative and qualitative measurements are represented. The model is then operationalized by constructing desirability functions for each criterion. The combined results provide an overall numerical score for each technology under consideration as well as criteria desirability gaps. This model is useful for assessing photovoltaic technologies from varying worldviews such as the electric utility worldview, the photovoltaic manufacturer's worldview, or the national policy worldview. This model can also provide guidance to decision makers and practitioners on areas of improvement for a selected technology. The research utilizes the electric utility worldview as a case study.
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Raza, Khalil. "Experimental Assessment of Photovoltaic Irrigation System". Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1411072971.
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Eronini, Nnamdi. "The Adoption Of solar photovoltaic systems among industries and residential houses in southern Nigeria". Thesis, Mittuniversitetet, Avdelningen för ekoteknik och hållbart byggande, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-22865.
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The shortage of electricity in Nigeria creates a huge gap between demand and supply, making individuals and organizations look for alternatives to obtain regular supply of power. The objective of this study was divided into two parts. First identify the barriers and drivers of the adoption of solar PV systems among home owners and organisations in Rivers State Nigeria. Second, identify the challenges faced by the suppliers of this product for small and large scale suppliers. In order to achieve the objectives of this study, a qualitative research approach was used to carry out the study. A loosely-structured interview and a well-structured interview were used as the method. Findings from this study suggest that the need for a regular power supply was enough to motivate residential adopters to purchase and install solar PVC's and sustainability was a sufficient driver to encourage adoption among organizations interviewed in this study. On the other hand, inadequate policies to encourage subsidies, high cost, difficulty to access finances, high interest rates 20%-22% and short period of payback (3years) for loans involving renewable technology were identified as barriers among residential adopters. Lack of implementation of policies for example, double standard shown by custom officials at ports against the zero tax on importation of renewable energy products set by the government, low level of awareness among the public and lack of organized co-oprative group which provides advisory information to potential adopters were among the barriers identified within this study from interviews conducted with suppliers of solar PV systems.
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Sharma, Pratibha. "Modeling, Optimization, and Characterization of High Concentration Photovoltaic Systems Using Multijunction Solar Cells". Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/35917.
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Recent advancements in the development of high-efficiency multijunction solar cells
have led to a renewed interest in the design and implementation of high concentration photovoltaic systems. With the emergence of novel materials and design structures, understanding the operation of multijunction solar cells has become a challenging task. Modeling and simulation hence play an important role in the analysis of such devices. In this dissertation, techniques for accurate optoelectrical modeling of concentrating photovoltaic systems, based on multijunction solar cells, are proposed. A 2-dimensional, distributed circuit model is proposed, parametrized to values obtained by numerical modeling of three multijunction cell designs, namely: a three-junction, lattice matched design, a three-junction lattice-mismatched, inverted metamorphic design, and a four-junction,lattice matched design. Cell performance for all the three designs is evaluated under both
uniform and nonuniform illumination profiles at high concentrations and efficiency enhancement by optimizing finger spacing is proposed. The effect of luminescent coupling from higher bandgap subcells is also determined.Fresnel-lens based, refractive concentrating optical systems are modeled and optimized
using an optical ray-tracing simulator at two different concentrations, with and without
a secondary optical element. The corresponding optical efficiency, acceptance angle, and the degree of nonuniformity are determined for each optical system. An integrated approach,combining optical design with electrical modeling is proposed for optimizing the multijunction solar cell in tandem with the corresponding concentrating optics. The approach is validated by on-sun, acceptance angle measurements, using a three-junction,lattice-matched cell. Also, temperature effects are modeled and are experimentally validated for a three-junction, lattice-matched design. Experimental results with a single-junction, dilute-nitride cell, targeted for four-junction operation, are presented as well. A modified distributed circuit model is used for analysis of temperature effects in a four-junction solar cell, and the results under both uniform and nonuniform temperature profiles are presented.
When implemented, the designs and their corresponding analyses, may result in new
insights into the development of CPV systems, thereby enabling enhanced efficiencies at higher concentrations.
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Yandt, Mark. "Characterization and Performance Analysis of High Efficiency Solar Cells and Concentrating Photovoltaic Systems". Thesis, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/20535.
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As part of the SUNRISE project (Semiconductors Using Nanostructures for Record Increases in Solar-cell Efficiency), high efficiency, III-V semiconductor, quantum-dot-enhanced, triple-junction solar cells designed and manufactured by Cyrium Technologies Inc. were integrated into OPEL Solar, MK-I, Fresnel-lens-based, 550x concentrating modules carried on a dual axis tracker.
Over its first year of operation 1.8 MWh of AC electrical energy was exported to the grid. Measurements of the direct and indirect components of the insolation, as well as the spectral irradiance of light incident on the demonstrator in Ottawa, Canada are presented. The system efficiency is measured and compared to that predicted by a system model to identify loss mechanisms so that they can be minimized in future deployments.
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Koran, Ahmed Mohammed. "Photovoltaic Source Simulators for Solar Power Conditioning Systems: Design Optimization, Modeling, and Control". Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/23681.
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This dissertation presents various systematic design techniques for photovoltaic (PV) source simulators to serve as a convenient tool for the dynamic performance evaluation of solar power conditioning systems and their maximum power point tracking algorithms. A well-designed PV source simulator should accurately emulate the static and the dynamic characteristic of actual PV generator. Four major design features should be adopted in any PV source simulator: (i) high power-stage efficiency, (ii) fast transient response-time, (iii) output impedance matching with actual PV generator, and (iv) precise reference generation technique. Throughout this research, two different PV source simulator systems are designed, modeled, and experimentally verified. The design of the first system focuses mainly on creating new reference generation techniques where the PV equivalent circuit is used to precisely generate the current-voltage reference curves. A novel technique is proposed and implemented with analog components to simplify the reference signal generator and to avoid computation time delays in digital controllers. A two-stage LC output filter is implemented with the switching power-stage to push the resonant frequency higher and thus allowing a higher control-loop bandwidth design while keeping the same switching ripple attenuation as in the conventional one-stage LC output filter. With typical control techniques, the output impedance of the proposed simulator did not match the closed-loop output impedance of actual PV generator due to the double resonant peaks of the two-stage LC output filter. Design procedures for both control and power-stage circuits are explained. Experimental results verify the steady-state and transient performance of the proposed PV source simulator at around 2.7 kW output.
The design concept of the first simulator system is enhanced with a new type of PV source simulator that incorporates the advantages of both analog and digital based simulators. This simulator is characterized with high power-stage efficiency and fast transient response-time. The proposed system includes a novel three-phase ac-dc dual boost rectifier cascaded with a three-phase dc-dc interleaved buck converter. The selected power-stage topology is highly reliable and efficient. Moreover, the multi-phase dc-dc converter helps improve system transient response-time though producing low output ripple, which makes it adequate for PV source simulators.
The simulator circuitry emulates precisely the static and the dynamic characteristic of actual PV generator under different environmental conditions including different irradiance and temperature levels. Additionally, the system allows for the creation of the partial shading effect on PV characteristic. This dissertation investigates the dynamic performance of commercial and non-commercial solar power conditioning systems using the proposed simulator in steady-state and transient conditions. Closed-loop output impedance of the proposed simulator is verified at different operating conditions. The impedance profile --magnitude and phase- matches the output impedance of actual PV generator closely. Mathematical modeling and experimental validation of the proposed system is thoroughly presented based on a 2.0 kW hardware prototype. The proposed simulator efficiency including the active-front-end rectifier and the converter stages at the maximum power point is 96.4%.
Ph. D.
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Perez, de Larraya Espinosa Mikel. "Photovoltaic Power Plant Aging". Thesis, Högskolan i Gävle, Avdelningen för byggnadsteknik, energisystem och miljövetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-33252.
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One of the most pressing problems nowadays is climate change and global warming. As it name indicates, it is a problem that concerns the whole earth. There is no doubt that the main cause for this to happen is human, and very related to non-renewable carbon-based energy resources. However, technology has evolved, and some alternatives have appeared in the energy conversion sector. Nevertheless, they are relatively young yet. Since the growth in renewable energies technologies wind power and PV are the ones that have taken the lead. Wind power is a relatively mature technology and even if it still has challenges to overcome the horizon is clear. However, in the PV case the technology is more recent. Even if it is true that PV modules have been used in space applications for more than 60 years, large scale production has not begun until last 10 years. This leaves the uncertainty of how will PV plants and modules age. The author will try to analyse the aging of a specific 63 kWp PV plant located in the roof of a building in Gävle, monitoring production and ambient condition data, to estimate the degradation and the new nominal power of the plant. It has been found out that the degradation of the system is not considerable. PV modules and solar inverters were studied, and even if there are more elements in the system, those are the principal ones. PV modules suffered a degradation of less than 5%, while solar inverters’ efficiency dropped from 95,4% to around 93%.
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Hiranvarodom, Somchai. "Design and analytical evaluation of stand-alone photovoltaic power systems for rural areas in Thailand". Thesis, Northumbria University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340072.
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Macabebe, Erees Queen Barrido. "Investigation of device and performance parameters of photovoltaic devices". Thesis, Nelson Mandela Metropolitan University, 2009. http://hdl.handle.net/10948/1003.
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In order to investigate the influence of parasitic resistances, saturation current and diode ideality factor on the performance of photovoltaic devices, parameter extraction routines employing the standard iteration (SI) method and the particle swarm optimization (PSO) method were developed to extract the series resistance, shunt resistance, saturation current and ideality factor from the I-V characteristics of solar cells and PV modules. The well-known one- and two-diode models were used to describe the behavior of the I-V curve and the parameters of the models were determined by approximation and iteration techniques. The SI and the PSO extraction programmes were used to assess the suitability of the one- and the two-diode solar cell models in describing the I-V characteristics of mono- and multicrystalline silicon solar cells, CISS- and CIGSS-based solar cells. This exercise revealed that the two-diode model provides more information regarding the different processes involved in solar cell operation. Between the two methods developed, the PSO method is faster, yielded fitted curves with lower standard deviation of residuals and, therefore, was the preferred extraction method. The PSO method was then used to extract the device parameters of CISS-based solar cells with the CISS layer selenized under different selenization process conditions and CIGSS-based solar cells with varying i-ZnO layer thickness. For the CISS-based solar cells, the detrimental effect of parasitic resistances on device performance increased when the temperature and duration of the selenization process was increased. For the CIGSS-based devices, photogeneration improved with increasing i-ZnO layer thickness. At high forward bias, bulk recombination and/or tunneling-assisted recombination were the dominant processes affecting the I-V characteristics of the devices. v Lastly, device and performance parameters of mono-, multicrystalline silicon and CIS modules derived from I-V characteristics obtained under dark and illuminated conditions were analyzed considering the effects of temperature on the performance of the devices. Results showed that the effects of parasitic resistances are greater under illumination and, under outdoor conditions, the values further declined due to increasing temperature. The saturation current and ideality factor also increased under outdoor conditions which suggest increased recombination and, coupled with the adverse effects of parasitic resistances, these factors result in lower FF and lower maximum power point. Analysis performed on crystalline silicon and thin film devices utilized in this study revealed that parameter extraction from I-V characteristics of photovoltaic devices and, in particular, the implementation of PSO in solar cell device parameter extraction developed in this work is a useful characterization technique.
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Doshi, Parag Mahendra. "Fundamental understanding and integration of rapid thermal processing, PECVD, and screen printing for cost-effective, high-efficiency silicon photovoltaic devices". Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/14783.
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Zhang, Yi Zhong. "Experimental investigations on a two-axis sun-tracking concentrated photovoltaic-thermal system cooled by phase change material". Thesis, University of Macau, 2018. http://umaclib3.umac.mo/record=b3950058.
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Eskandari, Rahmatollah. "Ferroelectric-Semiconductor Systems for New Generation of Solar Cells". ScholarWorks@UNO, 2017. http://scholarworks.uno.edu/td/2318.
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This dissertation includes two parts. In the first part the study is focused on the fabrication of multifunctional thin films for photovoltaic applications. There is no doubt about the importance of transforming world reliance from traditional energy resources, mainly fossil fuel, into renewable energies. Photovoltaic section still owns very small portion of the production, despite its fast growth and vast research investments. New methods and concepts are proposed in order to improve the efficiency of traditional solar cells or introduce new platforms. Recently, ferroelectric photovoltaics have gained interest among researchers. First objective in application of ferroelectric material is to utilize its large electric field as a replacement for or improvement of built-in electric field in semiconductor p-n junctions which is responsible for the separation of generated electron-hole pairs. Increase in built in electric field will increase open-circuit voltage of the solar cell.
In this regard, thin films of ferroelectric hafnium dioxide doped with silicon have been fabricated using physical vapor deposition techniques. Scanning probe microscopy techniques (PFM and KPFM) have been employed to analyze ferroelectric response and surface potential of the sample. The effects of poling direction of the ferroelectric film on the surface potential and current-voltage characteristics of the cell have been investigated. The results showed that the direction of poling affects photoresponse of the cell and based on the direction it can either improved or diminished.
In the second part of this work, epitaxial thin films have been synthesized with physical vapor deposition techniques such as sputtering and electron beam evaporation for the ultimate goal of producing multifunctional three-dimensional structures. Three-dimensional structures have been used for applications such as magnetic sensors, filters, micro-robots and can be used for modification of the surface of solar cells in order to improve light absorption and efficiency. One of the important techniques for producing 3-D structures is using origami techniques. The effectiveness of this technique depends on the control of parameters which define direction of bending and rolling of the film or curvature of the structure based on the residual stress in the structure after film’s release and on the quality and uniformity of the film. In epitaxially grown films, the magnitude and direction of the stress are optimized, so the control over direction of rolling or bending of the film can be controlled more accurately. For this purpose, deposition conditions for epitaxy of Zn, Fe, Ru, Ti, NaCl and Cr on Si, Al2O3 or MgO substrates have been investigated and optimized. Crystallinity, composition and morphology of the films were characterized using reflective high energy diffraction (RHEED), Auger electron spectroscopy (AES), energy dispersive X-ray (EDX), and scanning electron microscopy (SEM).
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Prichard, Martin Edward. "SINGLE PHASE MULTILEVEL INVERTER FOR GRID-TIED PHOTOVOLTAIC SYSTEMS". UKnowledge, 2015. http://uknowledge.uky.edu/ece_etds/81.
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Multilevel inverters offer many well-known advantages for use in high-voltage and high-power applications, but they are also well suited for low-power applications. A single phase inverter is developed in this paper to deliver power from a residential-scale system of Photovoltaic panels to the utility grid. The single-stage inverter implements a novel control technique for the reversing voltage topology to produce a stepped output waveform. This approach increases the granularity of control over the PV systems, modularizing key components of the inverter and allowing the inverter to extract the maximum power from the systems. The adaptive controller minimizes harmonic distortion in its output and controls the level of reactive power injected to the grid. A computer model of the controller is designed and tested in the MATLAB program Simulink to assess the performance of the controller. To validate the results, the performance of the proposed inverter is compared to that of a comparable voltage-sourced inverter.
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Chevrier, Michèle. "Towards new π-conjugated systems for photovoltaic applications". Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT206/document.
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Le développement des énergies renouvelables est aujourd’hui devenu un enjeu mondial majeur comme alternative aux énergies fossiles dans la production d'énergie. Parmi elles, l’énergie solaire est considérée comme la source la plus prometteuse, permettant de couvrir l’ensemble des besoins énergétiques liés à l’activité humaine. Les cellules photovoltaïques les plus performantes aujourd’hui, entre 16 et 18 % en modules, sont composées de silicium, un semi-conducteur inorganique. Cependant, leur coût de production élevé a nécessité le développement de matériaux alternatifs moins couteux. Parmi les voies explorées, les cellules solaires organiques ont émergé comme une alternative prometteuse pour produire l’électricité à faible coût. Le sujet de cette thèse s’intègre dans ce contexte de recherche. Deux types de cellules solaires ont été étudiés : les cellules à hétérojonction en volume (BHJ) et sensibilisées au colorant (DSSCs). Le courant photogénéré repose généralement (i) dans les cellules BHJ, sur le transfert entre de charge entre un polymère donneur et un accepteur d’électrons (fullerène), tels que le couple poly(3-hexyl)thiophène (P3HT) et [6,6]-phényl-C61-butanoate de méthyle (PCBM), et (ii) dans les DSSCs, la sensibilisation de la surface d’un semi-conducteur inorganique tel que l’oxyde de titane par un colorant et la présence d’un électrolyte, jouant le rôle de médiateur redox. Bien qu’ayant atteint des rendements de photoconversion respectifs de 5 et 13 %, ces cellules nécessitent des améliorations pour une commercialisation à grande échelle. Tout d’abord, les performances des cellules BHJ à base de P3HT sont considérablement limitées par sa faible absorption, ne couvrant pas la globalité du spectre solaire. Afin de palier ce problème, nous avons combiné le P3HT avec des chromophores, i.e. des porphyrines, ayant une absorption plus étendue. Ensuite, pour assurer une meilleure extraction des charges au sein du dispositif, une couche interfaciale cathodique à base de polyélectrolytes pi-conjugués a été ajoutée. Enfin, des colorants extraits de la biomasse ont été préparés afin de remplacer les colorants coûteux à base de ruthénium. En outre, les électrolytes liquides étant volatils et corrosifs, ce qui limite considérablement la stabilité des DSSCs, des électrolytes solides à base de polymères ont été étudiés comme alternativeAmong renewable energies, the sunlight has by far the highest theoretical potential to meet the worldwide need in energy. Photovoltaic devices are thus currently the subject of intense research for low-cost conversion of sunlight into electrical power. In particular, organic photovoltaics have emerged as an interesting alternative to produce electricity due to their low manufacturing cost compared to silicon solar cells, their mechanical flexibility and the versatility of the possible chemical structures. In this dissertation, we focused our research on the development of new organic pi-conjugated materials for organic solar cells applications. Two types of solar cells have been studied during this work: bulk heterojunction and dye-sensitized solar cells. The charge transfer leading to the photocurrent is usually based on (i) a polymer donor and a fullerene acceptor in BHJ solar cells, such as the widely studied poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) materials and (ii) a metal oxide (titanium oxide) sensitized with a dye and an electrolyte in DSSCs. Despite power conversion efficiencies have reached 5 and 13 % respectively for these two types of devices, they still display several drawbacks that limit their commercialization. P3HT displays a narrow absorption of the solar spectrum thus limiting the conversion efficiency. To overcome this limitation, we combined P3HT with chromophores, i.e. porphyrins, having an extending absorption. Then, to ensure better charge transfer and extraction within the device, a cathode interfacial layer based on cationic pi-conjugated polyelectrolytes was added. Finally, dyes extracted from the biomass (chlorophyll a derivatives) were synthesized to replace the expensive ruthenium dyes in DSSCs. Since liquid electrolytes are volatile and corrosive, which considerably limit the DSSCs stability, solid polymer electrolytes were also developed as an alternative
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Linde, Daniel. "Evaluation of a Flat-Plate Photovoltaic Thermal (PVT) Collector prototype". Thesis, Högskolan Dalarna, Energiteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:du-24061.
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This Master thesis, in collaboration with Morgonsol Väst AB, was completed as a part of the Solar Energy engineering program at Dalarna University. It analyses the electrical and thermal performance of a prototype PVT collector developed by Morgonsol Väst AB. By following the standards EN 12975 and EN ISO 9806 as guides, the thermal tests of the collector were completed at the facility in Borlänge. The electrical performance of the PVT collector was evaluated by comparing it to a reference PV panel fitted next to it. The result from the tests shows an improved electrical performance of the PVT collector caused by the cooling and a thermal performance described by the linear efficiency curve ηth=0.53-21.6(Tm-Ta/G). The experimental work in this thesis is an initial study of the prototype PVT collector that will supply Morgonsol Väst with important data for future development and research of the product.
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OTTOSSON, SIMON. "Case study of Urban Solar Photovoltaic systems Technical and Economical performance in Nordic climates". Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302517.
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The thesis is conducted with Vasakronan for their PV sites. The aim of this thesis is to evaluate the techno-economical effectiveness of urban stationed solar photovoltaic systems in Nordic environments in terms of inverter and module performance. This is made through a case study to compare solar power optimizers and string inverters performances as well as a comparison of crystalline silicon modules to thin film modules performance. Five PV sites situated in Stockholm and Uppsala are evaluated and modeled using the software System Advisor Model to enable a case study with alterations of system congurations. The inverter congurations were tested for two sites. For one of the sites solar power optimizers are shown to be more benecial, improving the protability index by 5 % compared to using string inverters, while string inverters were the more favourable for one site with a 4 % protability index increase. The variation is highly dependent of the amount of surrounding infrastructure. The module congurations are tested for all five of the sites. The thin film modules provided an increased protability index value of 12 % and 15 % each for two of the sites while the silicon modules provided an increase between 5 % to 7 % for three of the sites. The result shows that thin film modules are more advantageous at certain intervals of tilt- and azimuth angles though less competitive for the typical installation presets.Uppsatsen utförs med Vasakronan på deras PV siter. Målet med uppsatsen är at utvärdera den techno-ekonomiska effektiviteten för stadsplacerade sol- cellessystem i nordiska klimat i form av prestanda av växelriktar- och modul teknologier. Detta utförs genom en fallstudie för att jämföra prestanda dels mellan solar power optimizers och växelriktare samt mellan kristallina- och tunnfilmsmoduler. Fem solcellssiter anlagda i Stockholm och Uppsala undersöks och modelleras i programmet System Advisor Model för att kunna skapa olika systemkongurationer. Växelriktarkongurationerna jämfördes för två siter. För en av siterna var solar power optimizers det mer fördelaktiga valet, det ökade lönsamhetsindex med 5 % mot att använda växelriktare. Medan det på den andra siten var mer fördelaktigt med växelriktare med en ökning av lönsamhetsindex på 4 %. Variationen var beroende av runtomkringliggande infrastruktur. Modulkongurationerna testas för alla fem siter. Tunnfilmsmodulerna gav på två av siterna en lönsamhetsindexökning på 12 % och 15 % var, medan kristallina moduler gav en lönsamhetsindexökning mellan 5 % och 7 % på tre av siterna. Resultaten visar att tunnfilmsmodulerna är mer fördelaktiga för särskilda intervall av lutnings- och azimutvinklar men mindre fördelaktiga för mer konventionella installationsförutsättningar.
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Kermani, Elnaz. "Manifold micro-channel cooling of photovoltaic cells for high efficiency solar energy conversion systems". College Park, Md. : University of Maryland, 2008. http://hdl.handle.net/1903/8974.
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Thesis (M.S.) -- University of Maryland, College Park, 2008.Thesis research directed by: Dept. of Mechanical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper
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Kristofersson, Filip, i Sara Elfberg. "Maximizing Solar Energy Production for Västra Stenhagenskolan : Designing an Optimal PV System". Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-384723.
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Skolfastigheter is a municipality owned real estate company that manages most of the buildings used for lower education in Uppsala. The company is working in line with the environmental goals of the municipality by installing photovoltaic systems in schools and other educational buildings. Skolfastigheter are planning to install a photovoltaic system in a school in Stenhagen. The purpose of this study is to optimally design the proposed system. The system will be maximized, which in this study entails that the modules will be placed on every part of the roof where the insolation is sufficient. The system will also be grid connected. The design process includes finding an optimal placement of the modules, matching them with a suitable inverter bank and evaluating the potential of a battery storage. Economic aspects such as taxes, subsidies and electricity prices are taken into account when the system is simulated and analyzed. A sensitivity analysis is carried out to evaluate how the capacity of a battery bank affects the self-consumption, self-sufficiency and cost of the system. It is concluded that the optimal system has a total peak power of almost 600 kW and a net present value of 826 TSEK, meaning that it would be a profitable investment. A battery bank is excluded from the optimal design, since increasing the capacity of the bank steadily decreased the net present value and only marginally increased the self-consumption and self-sufficiency of the system.
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van, Norden Stefan. "Investigation of the barriers for the diffusion of photovoltaic systems in Cape Town". Thesis, KTH, Entreprenörskap och Innovation, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-170139.
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The diffusion of photovoltaic (PV) systems is not only increasing in the current global electricity market, but everywhere there are barriers that are hampering the process. In this thesis the respective barriers for the diffusion of PV systems, as well as the current electricity market of Cape Town, situated in South Africa, will be analysed. The diffusion theory is used to highlight the factors that are affecting the diffusion process. The affecting factors are: relative advantage, compatibility, complexity, trialability and observability. In addition to this, the pre-diffusion phase focuses on the importance of the communication between the suppliers, adopters and the government in the diffusion process. Therefore an appropriate methodology was required to conduct this research, this was achieved by using a case study approach. The South African energy market was analysed with respect to the impact of policies, adopters and the suppliers of PV systems. Interviews with six local experts where conducted, to gather primary data from the suppliers’ perspective, mainly regarding how they perceive the barriers for the diffusion of PV systems. The results revealed that the diffusion of PV systems is still in the pre-diffusion stage, and faces numerous barriers. The outcomes of the analysis showed that the barriers could be categorized into four different themes namely: sociotechnical, management, economic and policy. Although the barriers could be categorized into different themes they are interrelated to each other. After analysing the results it became clear that the policies and the lack of involvement and communication of all actors, are the crucial barriers that need to be overcome for an effective diffusion process of PV systems in Cape Town.