68 research outputs found
High-Throughput Quality Inspection of Solar Cells Using Deep Learning Under Consideration of Its Sustainability Impact
No full textTo meet global market demands, it will remain important to further scale up photovoltaics (PV) production. During the production of solar cells, several defects can occur. Current approaches in quality inspection are reaching their speed limits. This thesis project evaluates the feasibility of faster quality inspection by using deep learning-based computer vision (CV) algorithms to detect production defects without human supervision at high speeds. The goal is to achieve this while reducing the necessary manual efforts to label (annotate) defects in the training data of such algorithms.The second goal of the project is to investigate in which ways and to which extent this innovation can impact the sustainability performance of the solar cell production process. Multiple scenarios are investigated using a Life Cycle Assessment (LCA) model. The results are used to estimate the potential large-scale impact of increasing solar cell production throughput.Industrial Ecolog
Corrosion of Titanium Electrode Used for Solar Saline Electroflotation
No full textThe solar electroflotation (EF) processes using saline electrolytes are today one of the great challenges for the development of electrochemical devices, due to the corrosion problems that are generated during the operation by being in permanent contact with Cl− ions. This manuscript discloses the corrosion behavior of titanium electrodes using a superposition model based on mixed potential theory and the evaluation of the superficial performance of the Ti electrodes operated to 4 V/SHE solar electroflotation in contact with a solution of 0.5 M NaCl. Additionally provided is an electrochemical analysis of Ti electrodes regarding HER, ORR, OER, and CER that occur during the solar saline EF process. The non-linear superposition model by mixed potential theory gives electrochemical and corrosion parameters that complement the information published in scientific journals, the corrosion current density and corrosion potential in these conditions is 0.069 A/m2 and −7.27 mV, respectively. The formation of TiO2 and TiOCl on the anode electrode was visualized, resulting in a reduction of its weight loss of the anode electrode
Caracterización de la celda fotovoltaica del dispositivo PowerFilm solar USB+AA charger y exploración de elementos generadores de baja potencia
No full textIngeniero MecánicoPregrad
Propuesta de mejora térmica a viviendas DFL 2 normadas termicamente según ART. 4.1.10
No full textTesis (Ingeniero Constructor)Este análisis y propuesta de mejora, tiene por objetivo principal esclarecer y
cuantificar los principales focos de puentes térmicos existentes en las viviendas
DFL-2 de Chile, para posteriormente aplicarlos a viviendas que estén bajo el alero
de la actual normativa térmica art. 4.1.1.0, las cuales como propuesta de mejora
serán evaluadas según sobre-norma, es decir, realizar el estudio térmico en 2
viviendas normadas acorde a su zonificación y posteriormente a la misma vivienda
evaluarla con un criterio térmico mayor acorde a las exigencias de la normativa,
así como también concretar empíricamente, una aislación extra normada que
otorgue a las viviendas en estudio una aislación del 100%, produciéndose así el
"efecto iglú" propuesto.
La finalidad del estudio es determinar posibles criterios de mejora a la normativa
térmica en función a los valores de resistencia térmica mínima propuestos, así,
aumentado la resistencia térmica de las viviendas en estudio, mejorando el confort
térmico, además de cuantificar la inversión asociada y en función de esto, estimar
finalmente un "Pay Back" y ahorros correspondientes de las mejoras. Como
criterio adicional, se contemplan 3 alturas interiores (piso - cielo) distintas para las
viviendas en estudio, para así estimar que en qué influye térmicamente ésta
variable, en el consumo de kilo watts anual.
Inicialmente se llevó a cabo una cuantificación de los puentes térmicos de las
viviendas en estudio, con el fin de conocer las pérdidas energéticas de las
mismas, esto con el objetivo de brindar diversos tipos de soluciones constructivas,
con respecto al cerramiento sobrenormado de la vivienda, posteriormente
emplazar y proponer las viviendas en estudio para así poder ser evaluadas
térmicamente, consumo anual de kilo watts y aporte calórico solar. Finalmente se
determina el monto asociado a la inversión y estimar si es conveniente llevarla a
cabo.This analysis and proposed improvements, mainly aims to clarify and quantify the main sources of existing thermal bridges in the DFL-2 households of Chile, later apply to homes that are under the umbrella of the current thermal regulations Art.
4.1.10, which as proposed improvement will be evaluated according to over-rule, in did, the thermal study performed in 2 households normed according to its zoning and then to evaluate the same housing with a thermal criterion increased according to the demands of the regulations, as well as down empirically, extra insulation normed granting to study an insulation housing 100%, producing the "igloo effect"
proposed.
The purpose of the study is to identify possible approaches for improving the thermal regulation according to the values proposed minimum thermal resistance, thus increasing the thermal resistance of the housing study, improving thermal comfort, in addition to quantifying the associated investment and based on this, finally estimate a "Pay Back" and corresponding savings improvements. As an additional criterion, 3 interior heights (flat-sky) than for homes in studio, are contemplated in order to estimate how heat affects this variable, the annual consumption of kilo watts.
Initially conducted a quantification of the thermal bridges of the houses in the study, in order to meet the energy losses of the same, this with the aim of providing various types of building solutions on the enclosure housing on normed subsequently deploy and publish study homes in order to be thermally assessed, annual consumption of kilo watts and solar energy intake. Finally the amount associated with investment and assess whether it is appropriate to carry it out is determined
Solar Assisted Absorption Machine for the Fermentation Cooling and Maceration Heating Processes in the Winemaking Industry
No full textAbstractTwo of the key processes in winemaking are alcoholic fermentation and must maceration, both of which have a high demand of energy. Fermentation is an anaerobic process carried out by the metabolic action of a microorganism. During this process the temperature has an important effect on the fermentation kinetics [1,2]. As the fermentation is exothermic, most of the wineries use a cooling system composed of mechanical refrigeration cycles and cooling towers in order to control the process temperature. After the fermentation, the must is macerated at temperatures close to 30°C, during which the phenolic materials (e.g. tanins and coloring agents) are leached and balanced. The aim of this study is to assess the thermal performance of a novel system composed of an absorption machine driven by solar and biomass energy sources, thus investigating the behavior of the system in an industrial winemaking process. This system consists of a lithium bromide absorption machine, a solar thermal collector field and a biomass water heater. The system operates in different modes during summer and winter seasons, taking advantage of the seasonality of both the solar resource availability and the heating and cooling demands of the processes. The results indicate that the proposed system is able to supply 25% of the cooling demand during the summer and between 30 to 50% of the heating demand during the winter
Beam splitting filters applied to thermally de-coupled solar photovoltaic/thermal (PV/T) collectors
No full textThis investigation was focussed on the implementation of spectrally selective beam splitting filters in hybrid concentrating solar PV/T collectors. The main aim of this thesis was to systematically conduct an investigation using fundamental thermal, optical and experimental engineering techniques to overcome some of the long-standing challenges of thermally de-coupled PV/T technologies.
To efficiently utilise the entire spectrum, a general methodology for the solar spectrum partition in hybrid PV/T collectors was developed herein. To validate the results of the methodology, two different approaches have been investigated: (1) dichroic mirrors as reflective band-stop filters and, (2) nanofluids as band-pass filters. The design of (1) was addressed by using two different multilayers structures: SiNx/SiO2 and TiO2/SiO2. For (2), Ag/Si core/shell nano-discs were suspended in water creating a spectrally selective absorbing fluid. These methods were chosen because they have potential to ultimately be mass produced at low fabrication cost.
A detailed optical and heat transfer model was developed for both approaches. Additionally, indoor and outdoor testing was carried out to validate the modelling results. Finally, a comparative economic model was presented to quantify the savings that could be achieved from different PV/T collectors using the methods detailed above. The experimental results were used as input in the economic analysis revealing that the hybridisation of a concentrated PV system using nanofluids as selective absorbing fluids could be an economically viable option.
Overall, the author hopes that this study will enable further commercial development of PV/T collectors using beam splitting. In particular, nanofluids as selective absorbing fluids seems to be a promising approach to be investigated further as they are relatively inexpensive (as compared to thin film filters) and could be incorporated as the thermal receiver of high concentration solar PV/T technologies
Comprendiendo nuestro mundo desde las estrellas : Una propuesta de enseñanza interdisciplinaria en las ciencias sociales.
No full textEl proyecto "Comprendiendo nuestro mundo desde las estrellas: Una propuesta de enseñanza interdisciplinaria en las ciencias sociales." busca enriquecer la enseñanza de ciencias sociales al integrar conceptos astronómicos para una comprensión más profunda de fenómenos geográficos en tercer grado de primaria. Aborda la falta de exploración interdisciplinaria entre ciencias sociales y astronomía, ampliando el enfoque tradicional. Mediante investigación teórica y contextualización histórica, se busca aportar significativamente a la enseñanza de estos fenómenos desde una perspectiva astronómica.Licenciado en Ciencias SocialesPregradoLinea de Investigación de Educación Geográfica
Evaluation of photocatalytic treatment of industrial wastewater using solar energy
No full textRESUMEN: En este trabajo se evaluó la degradación fotocatalítica de contaminantes acuosos provenientes de una
industria de productos químicos, empleando un fotorreactor solar de placas planas de vidrio corrugado dispuestas en forma de cascada, sobre las cuales se soportaron películas de TiO2 (Degussa P-25) / SiO2, como sistema fotoactivo. Se estudió la influencia de tres variables en la eficiencia de descontaminación: cantidad de H2O2, volumen de agua a tratar y cantidad de TiO2 disperso, mediante un diseño de experimentos llevados a cabo en modo de operación discontinua por un periodo de 5 horas para cada ensayo. Los resultados obtenidos confirman a la Fotocatálisis Heterogénea (FH) como una tecnología viable de tratamiento en etapas previas a un tratamiento biológico ya que se alcanzaron porcentajes de reducción en la DQO que varían entre 6 y 46% y se obtuvieron efluentes biodegradables en todas las pruebas realizadas.ABSTARCT: Wastewater of a chemical industry was treated in a photocatalytic process, using a solar photoreactor made of glass corrugated flat plates that had been set in cascade and using Titanium Dioxide (Degussa P-25) as
photocatalyst that is supported on each one of them in film form. The influence of three variables in the
decontamination efficiency were studied: amount of H2O2, volume of water and amount of dispersed TiO2, by means of the accomplishment of fifteen experiments carried out in discontinuous operation mode by a period of 5 hours for each test. The obtained results allow to establish that the FH is a viable technology of treatment like previous stage to a biological treatment since percentage of reduction in the DQO varies between 6 and 46% and was managed to reach a biodegradable effluent in all tests
Life Cycle Assessment of an Organic Redox Flow Battery
No full textEnergy storage systems can play a vital role in the implementation of a sustainable energy grid by allowing the wide scale implementation of fluctuating renewable energy sources like wind and solar. Therefore it is expected that in the coming years, the total amount of energy storage systems will drastically increase. Analysing the sustainabilityof these storage systems before widespread implementation is therefore of great importance. In this thesis such a life cycle assessment has been conducted to assess the environmental sustainability of one type of energy storage system: the Organic Redox Flow Battery produced by the Baliht research group.Industrial Ecolog
Design and construction of a straight-wing glider type unmanned aerial vehicle with solar panels
No full textEn este documento se presenta el diseño y construcción de un vehículo aéreo no tripulado tipo de planeador, con una fuente de energía alterna solar que se conmutará con una batería en el momento en que esté por debajo de la tensión nominal del motor. Una estructura ligera que puede soportar celdas solares y una alta geometría de elevación.This document presents the design and construction of a air-vehicle glider type unmanned aerial vehicle with an alternating power source, solar, which will be switched with a battery at the time it is below the rated voltage of the Motor, the design is based on a lightweight structure that can withstand solar cells and a high lift geometry.Pregrad
- …
