We are facing a climate crisis, and the world needs to generate electricity in more climate neutral ways. One alternative is to use solar energy. The highest efficiency can be achieved if the surface normal is pointed towards the sun, instead of just having it stationary. To solve this, people make a system called a solar tracker. In this project a prototype of a solar tracker is made, which can follow the sun in any direction. The solar tracker consists of a mechanical structure, two DC-motors that move the structure, and a microcontroller that implements the regulator to control the motors. All the mechanical parts were constructed and then printed using a 3D-printer. Manual control was implemented for making troubleshooting and testing easier. The electrical system is soldered on an experimental board and then mounted with the motor driver and mechanical construction on a bottom structure. There are a few interesting things that could be further developed. One is to implement sensors at the start point and end point of the sun tracking so that the tracker can return to the starting point after the sunset. It would be interesting to scale up the construction a bit and make some more useful measurements on larger panels to see if the system is energy effective enough to be useful; to make some outdoor tests and see how the sensors and control system work in a real-world environment; and to investigate and eventually develop its ability to adapt to cloudy weather.

The Salish Sea is a ecologically important coastal region located on the southwest part of British Columbia. Optical measurements were taken using a set of hyperspectral radiometers, the SAS Solar Tracker developed by Satlantic. This sensor is installed on the Queen of Oak Bay ferry, that runs between Nanaimo and Vancouver, as part of the Ferry Ocean Colour Observation Systems (FOCOS) project. We developed a computer program to process the raw sensor data and generate remote sensing reflectance (Rrs) values. This performs similar functions to Prosoft, Satlantic’s own software to process the data. However, we added new features such as an additional preprocessing step to filter the data based on longitude, and new meteorological flag testing and wind speed calculations. The system was tested using Pearson correlation to compare our output with the output from Satlantic Prosoft. Testing helped us identify a few issues, such as adding longitude flags to remove data at the start and end of the trip where the sensor could produce inaccurate results if aiming at land instead of water. Another issue was where the SAS Solar Tracker does not update its pointing angle fast enough when the ferry makes sharp turns and could result in inaccurate data. / Graduate

L’agrivoltaïque, combinaison de panneaux photovoltaïques et d’une culture sur le même sol, a été proposé en 1982 comme solution au conflit d’usage des sols. Lancé en 2010 à Montpellier, le concept associant panneaux fixes et diverses cultures a fait la preuve d’une productivité combinée de la parcelle améliorée grâce, notamment, à l’acclimatation de la culture à l’ombre. Dans cette thèse, les panneaux fixes ont été échangés par des panneaux orientables au cours de la journée. L’objectif était d’optimiser l’orientation des panneaux pour maximiser la productivité combinée de la parcelle sans pénaliser la culture. Pour cela, la croissance et le développement de laitues ont été analysés en conditions contrôlées et en plein champ sous différentes modalités d’ombrage par panneaux fixes ou mobiles. Les panneaux mobiles ont permis d’améliorer la productivité combinée de la parcelle par rapport à des panneaux fixes, avec un maintien de la production agricole dans certaines conditions. Une approche écophysiologique basée sur le développement de la plante, sa capacité à intercepter et convertir le rayonnement en biomasse, a révélé que les modalités d’ombrage avaient peu d’impact sur la mise en place de la surface foliaire malgré des différences de biomasse accumulée en rapport avec le rayonnement transmis à la plante. Des modifications du développement foliaire ont conduit à une meilleure utilisation du rayonnement transmis lorsque celui-ci était réduit. Ce travail a débouché sur une modélisation de l’impact de l’orientation des panneaux sur la biomasse des laitues permettant d’optimiser le pilotage des panneaux en fonction du scénario climatique et des objectifs de productions. / Agrivoltaic systems, combining solar panels and crops on the same land were proposed in the early 1980’s as a solution to solve land use conflict. Introduced in 2010 in Montpellier, the concept has proven itself associating fixed panels to multiple food crops. Total land productivity was improved, thanks to plant acclimation to shade. In this thesis, fixed panels were replaced with mobile panels, adjustable along the day. The aim of this work was to optimize solar panel orientations to maximise total land productivity without threatening the crop culture. Growth and development of lettuces were analysed in controlled conditions and in the field under several shading conditions by fixed or mobile panels. Total land productivity was improved with mobile panels in comparison with fixed panels, maintaining lettuce yield under certain conditions. Through an ecophysiological approach based on plant development and its ability to intercept and convert light into biomass, the different shading conditions were shown to have a small impact in the plant leaf area dynamic despite large differences in accumulated dry mass associated with transmitted radiation at the plant level. This was due to differences in leaf development resulted in higher use of the transmitted radiation when it was reduced. This study proposed a modelling approach of the incidence of panel orientations on lettuce dry mass at harvest. The model allows an optimisation of solar panels controlling as a function of climate scenario and crop and electricity production objectives.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Um concentrador solar parabÃlico à um tipo de refletor usado para aumentar a intensidade da radiaÃÃo em uma superfÃcie. Para que ocorra a reflexÃo adequada da radiaÃÃo solar, o refletor parabÃlico deve constantemente rastrear a posiÃÃo do sol de tal forma que os raios solares sejam refletidos em um tubo que se encontra na posiÃÃo de foco da parÃbola. A proposta deste trabalho à desenvolver um sistema eletrÃnico de controle de baixo custo para concentradores parabÃlicos aplicados à refrigeraÃÃo e proporcionar autonomia ao equipamento. TambÃm à apresentado um sistema mecÃnico para acionamento do rastreador. Por ser parte de um sistema de refrigeraÃÃo, o tubo colocado no foco da parÃbola deve sofrer processos de aquecimento e resfriamento. O sistema à constituÃdo de uma placa de controle com um microcontrolador em seu nÃcleo, sensores de luminosidade e sensores limitadores de movimento e um motor de passo responsÃvel pelo acionamento da estrutura mÃvel do concentrador solar. AtravÃs do sistema desenvolvido, pode-se fazer com que sejam atingidas temperaturas em torno de 180ÂC na superfÃcie externa do tubo coletor colocado na posiÃÃo de foco da parÃbola / A parabolic solar concentrator is a type of reflector utilized to increase the radiation intensity on a surface. In order to have a proper reflection of solar radiation, the parabolic reflector should constantly track the sunâs position so that solar rays are converged to a tube that is at the focus position of the parabola. The purpose of this study is to develop an electronic control system for low-cost parabolic trough concentrators applied to refrigeration process, and to provide autonomy to the equipment. It also is presented a mechanical system to guide the tracker. As part of a refrigeration device, the tube placed at the parabolaâs focus should experiment heating and cooling processes. The electronic system consists of a control plate with a microprocessor at its core, motion limiting and light sensors, and a step motor responsible for move the solar concentrator structure. Through this developed system, temperatures close to 180oC can be reached on external surface of the heat adsorption tube, which is placed on the position of parabolaâs focus

The purpose of this dissertation is to design the dual-axis solar tracker carrying the concentrator photovoltaic panels. The preamble of the dissertation shortly examines a photovoltaic cells development up to concentrators and the common support structures of solar power plants. The second part focuses on the engineering process itself. It includes the choice of the variant that suits best the requirements, the calculations of wind load and design of the various joints. The conclusion part is devoted to the evaluation, economy analysis of the construction and proposals for improvements.

The purpose of this project was to investigate how efficient it is to implement steering of a solar panel, in one or two axes. To determine how efficient it is, special consideration was taken to the energy usage of the driving system. Practical applications have also been considered with pros and cons. To answer the research questions a prototype was built and a controlled environment for testing was arranged. Rotating the panel in one axis resulted in a 26% energy increase and for the two-axis system a 56% energy increase compared to stationary panel. The use of stepper motors turned out to be not as efficient as needed, due to continuous use of energy at all times during operation. / Syftet med detta projekt var att undersöka hur effektivt det är att implementera styrning av en solpanel i en eller två axlar. För att kunna avgöra nyttan så togs det hänsyn till drivsystemet och hur mycket energi det gick åt för styrningen. Även praktiska tillämpningar kontrollerades och vilka fördelar och nackdelar som skulle erhållas. För att svara på frågeställningarna, tillverkades en prototyp som testades i en kontrollerad miljö. Genom att rotera panelen runt en axel ökar energiupptaget 26 % och för det tvåaxliga systemet 56 % jämfört med en stationär panel. Användningen av stegmotorer visade sig inte vara speciellt effektiv då det krävdes kontinuerlig strömmatning för att erhålla det motormoment som krävdes för att hålla panelen på plats.

Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2017-02-10T11:07:35Z No. of bitstreams: 1 Jair Carlos Muller_.pdf: 2333529 bytes, checksum: 36c56be5b98f22351456fbe4e419d28f (MD5) / Made available in DSpace on 2017-02-10T11:07:35Z (GMT). No. of bitstreams: 1 Jair Carlos Muller_.pdf: 2333529 bytes, checksum: 36c56be5b98f22351456fbe4e419d28f (MD5) Previous issue date: 2016-10-04 / CNPQ – Conselho Nacional de Desenvolvimento Científico e Tecnológico / Este trabalho apresenta um estudo geométrico de um refletor Fresnel linear para a produção de energia térmica com uso de um rastreador solar para orientação dos espelhos. A realização deste trabalho teve como base o estudo do sistema de coordenadas empregado para o cálculo da inclinação dos espelhos em função da posição do Sol em um determinado instante. O método utilizado considera que a radiação direta proveniente do Sol atinja o centro do espelho, cuja inclinação a cada instante permite a reflexão dessa radiação para o centro do absorvedor, situado a uma dada altura em relação ao plano contendo o eixo dos espelhos. Através do estudo da inclinação dos espelhos, foram analisadas as influencias causadas pela distância entre espelhos, altura do receptor, largura dos espelhos e o número de espelhos. Com estes parâmetros analisados, implementou-se uma simulação em MATLAB que forneceu valores de potência refletida no plano de entrada do concentrador secundário, valores de perdas por sombreamento, bloqueio, desfocagem e posição angular de cada fileira de espelho. Tendo estes dados como base foi construído um rastreador solar controlado por um micro controlador Arduino, que permite orientar as fileiras de espelhos com um único motor e eixo de acoplamento. O programa no micro controlador verifica data e hora como dados iniciais, depois as coordenadas geográficas de latitude 29º 45’ 17,979” S e longitude 51º 9’ 1,019” W do local. Assim, foi possível comprovar, através de imagens refletidas pelos espelhos no receptor secundário, que os parâmetros de posição angular estão corretos e que a concentração dos raios solares no absorvedor do concentrador secundário tem precisão adequada, fornecendo ao sistema confiabilidade para sua utilização. / This paper presents a geometric study of a linear Fresnel reflector for the production of thermal energy with use of a solar tracker for orientation of mirrors. This work was based on the study of the coordinate system used for the calculation of the slope of the mirrors as function of the sun’s position at a given time. The method considers that the solar direct radiation reaches the center of the mirror, whose slope at each instant allows the reflection of this radiation to the center of the absorber located at a given height from the plane containing the axis of the mirrors. Through the study of slope of mirrors, were analyzed the influences caused by the distance between mirrors, the height of receiver, width of the mirrors and the number of mirrors. With these parameters, it was implemented a simulation in MATLAB which provided power values reflected in the secondary concentrator inlet plane, values of losses by shading, blocking, by defocus and the angular position of each row of mirror. Having these data as base was built a controlled solar tracker by an Arduino micro controller, which allows directing the rows of mirrors with a single engine and coupling shaft. The program in micro controller checks the date and time as initial data, then the geographical coordinates of latitude 29° 45 ' 17.979 "S and longitude 51° 9 ' 1.019" W the local. Thus, it was possible to prove, through images reflected by mirrors on the secondary receiver, that the angular position parameters are correct and that the concentration of sunrays in the absorber secondary hub has adequate accuracy, providing the system reliability for its use.

Η παρούσα διπλωματική εργασία πραγματεύεται τη μελέτη και κατασκευή μιας διάταξης που παρακολουθεί συνεχώς τη θέση του ήλιου στον ουρανό και στρέφει αντίστοιχα ένα φωτοβολταϊκό πάνελ κατά τέτοιο τρόπο ώστε να μεγιστοποιείται η ένταση της ηλιακής ακτινοβολίας που προσπίπτει σε αυτό και επομένως και η ενεργειακή του απόδοση (solar tracker). Προκειμένου να πραγματοποιηθεί η εφαρμογή, το ίδιο το φωτοβολταϊκό πάνελ χρησιμοποιήθηκε ως ανιχνευτής της θέσης του ήλιου στον ουρανό απλουστεύοντας έτσι την κατασκευή και μειώνοντας το κόστος της καθώς δεν χρειάστηκαν επιπλέον αισθητήρες. Συγκεκριμένα, ανά τακτά χρονικά διαστήματα δειγματοληπτούνταν η τιμή της τάσης στα άκρα του φωτοβολταϊκού πάνελ από τον μικροελεγκτή msp430F169 της εταιρείας texas instruments, αποθηκεύονταν στους καταχωρητές του και αφού μετατρεπόταν το σήμα από αναλογικό σε ψηφιακό συγκρινόταν με τις προηγούμενες τιμές. Ανάλογα με το αποτέλεσμα της σύγκρισης, ο μικροελεγκτής έδινε εντολή στον κινητήρα που κατεύθυνε το φωτοβολταϊκό πάνελ να κινηθεί στην αντίστοιχη κατεύθυνση. Η διαδικασία επαναλαμβανόταν μέχρις ότου βρεθεί το σημείο εκείνο όπου η τάση στα άκρα του γίνεται μέγιστη. Το σύστημα που κατασκευάσαμε περιλαμβάνει κίνηση γύρω από έναν άξονα. Συγκεκριμένα παρακολουθεί την αζιμουθιακή κίνηση του ήλιου ξεκινώντας από την ανατολή (Earth) και καταλήγοντας στη δύση (West). / The present thesis deals with the study and construction of a solar tracker that constantly detects the sun position to the sky and directs correspondingly a photovoltaic panel in order to maximize the intensity of solar radiation prostrating to it and as a result, its energy performance as well. In order the application to be realized, the same photovoltaic panel was used as detector of the sun position to the sky, simplifying the construction and reducing its cost, as no further sensors were required. Particularly, the point-to-point voltage value of the photovoltaic panel was regularly sampled by the microcontroller msp430F169 of the Texas Instruments Company, it was saved to the register, and after the signal was being converted from analog to digital, it was being compared to the previous value. Depending on the result of the comparison, the microcontroller ordered the motor directing the photovoltaic panel to move across the corresponding direction. The process was being repeated until a point was found were the point-to-point voltage value was the maximum. The system created includes motion around one axis. Particularly, it observes the azimuthal solar motion starting from East and ending to West

Made available in DSpace on 2014-12-17T14:56:16Z (GMT). No. of bitstreams: 1 JoseRVL_DISSERT.pdf: 1074051 bytes, checksum: 14c63dffcde0a8f8267956ed973bedb7 (MD5) Previous issue date: 2014-01-23 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The use of solar energy for electricity generation has shown a growing interest in recent years. Generally, the conversion of solar energy into electricity is made by PV modules installed on fixed structures, with slope determined by the latitude of the installation site. In this sense, the use of mobile structures with solar tracking, has enabled increased production of the generated energy. However, the performance of these structures depends on the type of tracker and the position control used. In this work, it is proposed position control a strategy applied for a solar tracker, which will be installed in Laboratory of Power Electronics and Renewable Energy (LEPER), located in the Federal University of Rio Grande do Norte (UFRN). The tracker system is of polar type with daily positioning east-west and tilt angle manual adjustment in the seasonal periods, from north to south / O aproveitamento da energia solar para gera??o de energia el?trica tem apresentado um crescente interesse nos ?ltimos anos. Geralmente nestes sistemas, a convers?o de energia solar em el?trica ? realizada por m?dulos fotovoltaicos, instalados em estruturas fixas, com inclina??o determinada em fun??o da latitude do local de instala??o. Neste sentido, o uso de estruturas m?veis, com rastreamento solar, tem possibilitado o incremento da produ??o da energia gerada. Por?m, o desempenho dessas estruturas depende do tipo de rastreador instalado e do tipo de controle de posi??o utilizado. Nesta disserta??o, ? empregada uma estrat?gia de controle de posi??o aplicada a um rastreador solar, que ser? instalado no Laborat?rio de Eletr?nica de Pot?ncia e Energias Renov?veis (LEPER), localizado na Universidade Federal do Rio Grande do Norte (UFRN). O rastreador ser? do tipo polar, com rastreamento di?rio no sentido leste-oeste e ajuste do ?ngulo de inclina??o manual nos per?odos sazonais, no sentido norte-sul

Orientadora: Profa. Dra. Ahda Pionkoski Grilo Pavani / Coorientador: Prof. Dr. Ricardo da Silva Benedito / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Energia, Santo André, 2017.