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Thermodynamics is an engineering subject that is particularly difficult to teach and learn because it requires strong abstract theoretical concepts and extensive multidisciplinary knowledge. This manuscript introduces mind map learning as an alternative methodology for structuring both the learning and teaching processes in a transparent way for students in the context of thermodynamics. Mind maps help students to learn in a non-linear way promoting out-of-the-box thinking. In a quantitative pre–post study, the student knowledge outcomes were investigated through surveys and compared with the results of a control group. Factor analysis was carried out grouping four principal categories (66% of the total variance): visual insight to create links between pre-existing and new knowledge; motivation, related to curiosity to learn new concepts; applicability and critical thinking. Cronbach’s alpha was 0.84, which revealed good internal consistency. The results obtained are explained through constructivist and neuroeducation theories pointing out the relevance of the following concepts: alignment between pre-existing and new knowledge, learning improvement when multisensorial resources are used (like visual forms, font size, colors, hearing, speaking, etc.), and the impact of visual information on brain executive functions. The key to genuine education is curiosity and experience, as well as diving into hands-on learning, asking questions, and experimenting to truly grow.

El desarrollo de este trabajo se centra en el dimensionado del campo solar y en la estimación de la producción energética de una instalación termosolar de receptor central que trabajará con partículas sólidas como medio de trabajo y con un sistema TES también en partículas sólidas. Esta planta tiene como objetivo la producción de energía térmica a alta temperatura que será utilizada en un proceso para la producción de hidrógeno. El diseño de esta planta se ha realizado tomando como emplazamiento para la instalación la provincia de Huelva. Para el diseño se ha hecho uso de herramientas de simulación que permiten estimar la configuración óptima y su comportamiento energético, siendo éstas SolarPILOT, utilizada para el diseño del campo solar; y SAM, utilizada para la simulación del comportamiento de la planta. Se ha partido de unas restricciones impuestas por el uso que se pretende dar a la energía producida; estas restricciones atienden a la temperatura de trabajo, a la potencia térmica requerida por unidad de hidrógeno producido y al modo de operación, entre otras. Además de la simulación, se realiza una comparación de los resultados obtenidos para determinar la opción más adecuada según los requerimientos técnicos de la tecnología y del proyecto en el que se enmarca., The development of this project focuses on the sizing of the solar field and the study of the annual energy yield of a central receiver solar thermal power plant that will work with solid particles as a working medium and with a TES system based on solid particles, too. The objective of this plant is the production of high-temperature thermal energy that will be used in a process for hydrogen production. The design of this plant has been carried out taking the province of Huelva as the location for the installation. For the design of this plant, two simulation tools that allow estimating the optimal configuration and its energetic behavior have been used: SolarPILOT, used for the design of the solar field; and SAM, used to simulate the behavior of the plant. Beginning with some initial restrictions imposed by the intended use of the energy produced; these restrictions address the working temperature, the thermal power required per unit of hydrogen produced and the mode of operation, among others. In addition to the simulations, a comparison of the results obtained is made to determine the most appropriate option according to the technical requirements of the technology and the project in which it is part.

La economía y la sociedad están afrontando exigentes retos y profundas transformaciones que serán analizados en este Trabajo. La crisis medioambiental lleva años señalando la necesidad de tomar medidas urgentes y efectivas para avanzar hacia la descarbonización de la vida y de la actividad económica. Las sanciones recíprocas entre la Unión Europea y Rusia por la invasión de Ucrania han supuesto, junto a otros factores, un inédito aumento de los precios de los combustibles fósiles que ha puesto en jaque la recuperación económica tras la pandemia de COVID-19 con dinámicas inflacionarias sin precedentes, dado el insostenible grado de dependencia fósil hacia el exterior de España y de la UE. Con este panorama económico, el incremento del precio de la vida para los ciudadanos, y en particular el de la factura eléctrica, supone un golpe especialmente duro para aquellas familias que ya venían sufriendo serias dificultades económicas para poder sufragar unos servicios energéticos mínimos, como mantener una temperatura adecuada en su hogar. Este fenómeno es conocido como pobreza energética y tiene graves consecuencias para la salud física y mental, el desarrollo humano y la inclusión social, laboral o educativa de aquellos que la padecen. Por tanto, se trata de un problema real que afecta, al menos, a 9.000 linarenses, a 7 millones de personas a nivel nacional (15% de la población) y, de forma más grave que en el resto del país, a 1,7 millones de personas en Andalucía (el 20% de su población). Así, se muestra necesario luchar contra la pobreza energética desde los servicios públicos, aliviando la situación de estos hogares vulnerables y garantizando de forma efectiva el acceso a un bien tan básico como la energía. En este Trabajo se propone un rentable proyecto público de autoconsumo colectivo a partir de energía fotovoltaica con carácter social en Linares (Jaén) que trata de participar en la solución a algunos de los retos que debemos afrontar. Por un lado, proporciona a 35, In these days, our economy and society are facing demanding challenges and deep changes. The enviromental crisis has been claiming for years for urgent and effective measures to move towards a life and economic activities with no greenhouse gas emissions. The mutual sanctions between the European Union and Russia due to the invasion of Ukraine, in addition to other reasons, have brought an unprecedented rise in fossil fuel prices that threatens the recovery of the economy after the COVID-19 pandemic with strong inflationary trends, as a result of Spain’s and EU’s unsustainable level of dependence on abroad fossil fuels. Under this economic scenario, the increase in the cost of living for citizens, and more specifically in electricity bills, is a serious blow for those families who were already suffering great income problems in order to be able to pay for essential energy needs, such as keeping their homes at an adequate temperature. So-called energy poverty, this phenomenon has dangerous consequences for physical and mental health, human development and the social, occupational or educational inclusion of those who suffer from it. Therefore, this is a real problem affecting at least 9,000 people from Linares, 7 million spanish citizens (15% of the population) and, more severely than in the whole country, 1.7 million people in Andalusia (20% of its population). In that way, it is imperative to fight against energy poverty through public services, easing the dramatic situation of these families and effectively ensuring access to such a vital commodity as energy. This Study proposes a profitable public project of collective self-consumption from photovoltaic energy with a social aim in Linares (Jaen) that attempts to be part of the solution to some of the challenges that we have to deal with as society. On the one hand, it provides 35 electricity supplies of the City Council with self-consumption of its own, cheap and local electrical energy, produced in a photovoltai

The classification of days according to the solar radiation features is one of the tools frequently used for the solar resource assessment, modelling or forecasting. Recent studies discuss the appropriate classification method or number of types of days, but these studies usually don’t take into account, at least in an explicit way, the relation between the types of days and the yield of solar plants. In this work, we compare the representativeness of the types of days defined by two classification methods from the viewpoint of the production of a Central Receiver (CR) and a Parabolic Trough (PT) solar plant. The selected classification methods are based on the daily solar radiation features: energy, variability and temporal distribution. So, in a first step, the days of a period of 16 years of measurements recorded in Seville (Spain) are classified by these two methods. In a second step, the daily gross productions of both CSP plants are estimated using System Advisor Model program. Then, the representativeness of the types of days of each classification method is evaluated according to the production of the CR and the PT plant by means of a methodology based on the clear sky yield index or kp index. Finally, the ARE and the annual relative RMSE and the MAE for the plants and classification methods analyzed are compared. Then, we can conclude, that the representativeness of the types of days of a classification method has a certain dependence on the plant that depends on the classification method applied.

In this paper, we present a description of how to use a web based tool employing the ND model by Larrañeta et al. [1]. The tool is suited for downscaling DNI, GHI or coupled DNI and GHI from 1-h to 1-min. It requires only an annual solar radiation dataset in the hourly resolution as input and provides 1-min data in any location without local adaptation. We have applied the tool in three locations with different climates. The similitude between measured and generated DNI distributions has been evaluated through the Kolmogorov-Smirnov test Integral (KSI) for annual synthetic 1-min datasets. Obtained KSI values range from 6.2 W/m2 to 11.5 W/m2.

In this work, we test and improve an algorithm proposed in previous studies to generate synthetic series of plausible solar years (PSY). The method provides 100 synthetic years of coupled global horizontal irradiance (GHI) and direct normal solar irradiance (DNI) in 1-min resolution. The algorithm uses 10–20 years of hourly coupled GHI + DNI datasets that can be retrieved for most of the locations of the world from satellite estimates. The method consists of three steps. In the first step, we use the probability integral transform method to obtain 100 annual set series at monthly scale. The second step, we downscale the synthetic sets from monthly to daily time resolution using a first-order autoregressive model (AR 1). In the last step, we use ND model for generate the 1-min synthetic data sets from daily sets. The algorithm is evaluated at five locations with different type of climate according to the Koppen-Geiger classification and at different temporal scales: annual, monthly, daily, and 1-min resolution. In all cases, synthetic PSYs series cover a wider range of scenarios than the observed series but maintaining their distribution. Results suggest that the synthetically generated PSYs are capable to reproduce the natural variability of the solar resource at any location facilitating the stochastic simulation of solar harnessing systems.

La demanda de energía de un país está estrechamente relacionada con su producto interno bruto, con su capacidad industrial y con el estándar de vida alcanzado por sus habitantes. Es por ello que el petróleo, como fuente energética principal desde mediados del siglo XX, juega un papel estratégico en nuestra sociedad. La creciente demanda de este combustible fósil durante los últimos años, y las reservas limitadas de los crudos más económicos, están incrementando el interés de la industria en la extracción de crudos pesados. De entre todos los métodos disponibles para la extracción de crudos pesados, la inyección de vapor es el método más extendido. El incremento de la movilidad del crudo como resultado del efecto de la cámara de vapor en el interior del yacimiento, hace viable la explotación de crudos tradicionalmente poco rentables. La generación del vapor de inyección implica sin embargo un sobrecoste económico y medioambiental importante. Razón por la cual, la concentración solar, como fuente alternativa de energía para la generación de vapor de inyección, ha despertado el interés de la industria petrolera desde el nacimiento de la tecnología. Pese al temprano interés en la tecnología, su aplicación a proyectos reales ha sido limitada debido a los desafíos tecnológicos existentes. Uno de los más importantes es la diferencia entre la duración de la inyección de vapor en el yacimiento (alrededor de 7 años), y la vida útil del campo solar (hasta 25 años). Esta diferencia hace que en la mayoría de los casos, el campo solar únicamente puede aprovecharse durante una fracción reducida de su vida útil, lo que dificulta la viabilidad económica del proyecto. En esta tesis se detalla el diseño y la implementación real de un captador de concentración solar, que permite ser desmontado y transportado de manera económica al finalizar la fase de inyección de vapor. Permitiendo acompañar de esta forma la explotación secuencial de las zonas de inyección de un campo de petróleo. En, The energy demand of a country is closely related to its gross domestic product, its industrial capacity, and the standard of living of its inhabitants. That is the reason oil, as the main energy source since the middle of the 20th century, plays a strategic role in our society. The growing demand for this fossil fuel in recent years, and the limited reserves of cheap oil, are increasing the interest of the industry in the extraction of heavy crudes. Among the methods available today for the extraction of heavy oil, steam injection is by far the most widespread. The increased mobility of the oil as a result of the effect of the steam chamber within the reservoir, makes the exploitation of traditionally unprofitable reservoirs, economically feasible. The generation of injection steam comes nevertheless with a significant economic and environmental burden. Consequently, solar concentration as an alternative source of energy for the steam generation, has attracted the interest of the oil industry since the birth of technology. Despite the early interest in the technology, its application in real projects has been limited due to existing technological challenges. One of the most important is the difference between the duration of the steam injection in the reservoir (around 7 years), and the lifetime of the solar field (up to 25 years). This difference means that in most cases, the solar field can only be used during a small fraction of its lifetime, which ultimately makes the project not feasible. This thesis details the design and real implementation of a solar concentrating collector, capable of being disassembled and transported at the end of the steam injection phase. Allowing the solar generation to follow the development of the different injection areas within the oil field. The theoretical design of the collector comprises a detailed comparison between different constructive alternatives for each of its main components. The design principles assumed during the d

Integrals that are of interest in the analysis, design, and optimization of concentrating solar thermal systems (CST), such as the annual optical efficiency of the light collection and concentration (LCC) subsystem, can be accurately computed or estimated in two distinct ways: on the time domain and on the spatial domain. This article explores these two ways, using a case study that is highly representative of the commercial CST systems being deployed worldwide. In the time domain, the computation of these integrals are explored using 1-min, 10-min, and 1-h solar DNI input data and using The Cyprus Institute (CyI)’s High-Performance Computing (HPC) system and an open-source ray tracer, Tonatiuh++, being actively developed at CyI. In the spatial domain, the computation of these integrals is explored using SunPATH, another open-source software tool being actively developed at CyI, in tandem with Tonatiuh++. The comparison between the time and spatial domain approach clearly indicate that the spatial domain approach using SunPATH is dramatically more computationally efficient than the time domain approach. According to the results obtained, at least for the case study analyzed in this article, to compute the annual energy delivered by the LCC subsystem with a relative error less than 0.1%, it is enough to provide SunPATH with 1-h DNI data as input, request from SunPATH the sun position and weights of just 30 points in the celestial sphere, and run Tonatiuh++ to simulate these 30 points using 15 million rays per run. As the test case is highly representative, it is expected that this approach will yield similar results for most CST systems of interest.

Concentrated solar power (CSP) and photovoltaic (PV) solar systems can be hybridized, creating synergies: on one hand procuring dispatchability by storing thermal energy, and on the other hand generating electricity at a highly competitive prize. In this paper, we present an approach to the operation strategies and modes for integrated hybrid CSP + PV systems. We focus on parabolic trough (PT) solar plants, especially those operating in the south of Spain. Our study consists in the definition of suitable states for each of the subsystems that constitute a hybrid solar plant. We then propose modes from the combination of suitable states and establish the conditions for the transition between modes depending on the operation strategy. We propose two operation strategies: demand coverage and base load production. The results of this paper can be used in decision making for hybrid solar system simulation programs.

El Grupo de Termodinámica y Energías Renovables (GTER) suministra predicciones de irradiancia global horizontal y de irradiancia directa normal para Sevilla a través de su página Web. Estas curvas de irradiancia se calculan mediante dos pasos: la predicción de la iradiancia de cada una de las componentes en condiciones de cielo despejado y el uso de predicciones de nubosidad de otras fuentes. Las predicciones de irradiancia para cielo despejado del GTER presentan ciertos errores derivados de su método de predicción. Para estimar las irradiancias, el GTER utiliza dos ecuaciones, una para el cálculo de la directa y otra para la global. Ambas dependen de dos parámetros obtenidos a partir de las curvas de irradiancia reales registradas el día anterior en la estación. El problema radica en que el sistema solamente emplea estos parámetros de los días previos que presenten condiciones de cielo despejado. Por tanto, ante días previos nubosos, los parámetros son obtenidos del día despejado más cercano, empeorando así las predicciones. Esto unido a un método de detección de cielos nubosos y despejados, que no es capaz de distinguir entre periodos nubosos y con alta carga de aerosoles, hace necesario la implementación de un nuevo sistema que mejore las predicciones actuales. Con este fin se propone la utilización de modelos paramétricos para predecir las curvas de cielo despejado (CSI), los cuales estiman la irradiancia a partir de parámetros atmosféricos y de localización independientes de la irradiancia. De los múltiples modelos existentes, se decide probar 8: REST2, sSOLIS, ESRA, HE1, IP2002, K1980, mP1982 y mP2000. Las predicciones resultantes se comparan con los valores reales y las predicciones del GTER. En términos generales, de las tres componentes de irradiancia (global, directa y difusa) solamente para la global se obtienen resultados aceptables con respecto a los valores reales. Tanto la irradiancia directa como la difusa presentan resultados alejados de las medicio, The Grupo de Termodinámica y Energías Renovables (GTER) provides global and direct normal irradiance at Sevilla throught its website. These irradiance curves are estimated by two steps: The irradiance forecasts of each component on clear sky conditions and the cloud predictions provided by other sources. The clear sky irradiance predictions of GTER present some errors from its prediction method. The GTER uses 2 equations to estimate irradiances. One of them for the direct irradiance and other for the global irradiance. Both equations depend on 2 parameters which are obtained from the real irradiance curves of the previous day. The method only uses these parameters if the previous day presented clear sky. Therefore, if the previous day is cloudy, the 2 parameters are selected from the latest clear sky day. This increases predictions errors. Furthermore, sometimes the detection method of clear sky and cloudy sky are not able to differentiate between clouds and a high amount of aerosol. This leads an increase in predictions errors. Hence, a new irradiance prediction method that improves the current predictions is needed. This study proposes the clear sky irradiance (CSI) models as new approach to forecast the irradiance. The CSI models estimate the irradiance from atmospheric and locations parameters, which are not depend on actual irradiance values. Of all of existing models, 8 were analyzed: REST2, sSOLIS, ESRA, HE1, IP2002, K1980, mP1982 y mP2000. The resulting predictions are compared with the real values and the forecasts of GTER. Of the 3 components, only the global irradiance presents acceptable results regarding the real values. The direct and the diffuse irradiance show large differences with measurements. Comparing with the GTER forecasts, just global irradiance presents similar errors, even smaller than GTER, when updating atmospheric parameters on the day. Direct predictions of models are quite worse than GTER predictions. mP1982 model is the best model est

En este estudio, se van a analizar las distribuciones de irradiancia solar global horizontal registradas en cinco emplazamientos condicionadas a la masa óptica del aire, m, empleando datos minutales (alta frecuencia). Para representarlas, nos apoyaremos en el índice de claridad, kt , y posteriormente serán ajustadas por medio de funciones basadas en la estadística de Boltzmann. Además, intentaremos asemejar y relacionar estas distribuciones entre emplazamientos que cuenten con la misma clasificación Köppen-Geiger, apoyándonos para ello en el documento realizado por Fernández-Peruchena et al. (2015), con el que compararemos los resultados obtenidos. Este trabajo tiene la finalidad de ampliar el campo de conocimiento y comprobar la posibilidad de generar datos de irradiancia de alta frecuencia de manera sintética a partir de localizaciones con el mismo tipo de clima. Como resultado del estudio realizado, podemos afirmar que los emplazamientos seleccionados que cuentan con la misma clasificación climática Köppen-Geiger poseen unas distribuciones de probabilidad de kt similares para los distintos rangos de m analizados, a excepción de los emplazamientos con clima tropical, que muestran claras discrepancias para todos ellos.

En este trabajo se estudia y analiza la influencia de la latitud en el dimensionado de plantas termosolares de colectores cilindro parabólicos. Para llevar a cabo este estudio, se utiliza el programa de simulación System Advisor Model (SAM), en el que se introducen los datos meteorológicos de año de cielo despejado (CSY) y de año típico (TMY), para distintos emplazamientos caracterizados por su latitud. A través de un estudio paramétrico, se encuentra una combinación de parámetros claves en el dimensionado de una central de colectores cilindro parabólicos que hacen mínimo el Coste Nivelado de la Energía (LCOE) y, sobre los cuales, se realiza el análisis de la influencia de la latitud y de la meteorología a la hora de diseñar una planta termosolar de estas características. Los resultados obtenidos indican la clara dependencia del dimensionado de las plantas de concentración de energía solar de la irradiancia directa normal (DNI). Mientras mayor sea la DNI menor será el LCOE y las características del campo solar que se requieren para hacer este coste lo mínimo posible. A su vez, la DNI que llega a un emplazamiento depende de la latitud, de la nubosidad y de la turbiedad atmosférica, que también depende de la altitud de la localización. Entre los resultados de este trabajo, destaca que a medida que aumenta la latitud, la orientación N-S de los colectores va perdiendo sus ventajas frente a una orientación E-O. También se deduce que la meteorología tiene más influencia en el múltiplo solar si la orientación de los colectores es N-S que E-O. Mediante este trabajo se establece la importancia de considerar, a la hora de dimensionar un planta termosolar de colectores cilindro parabólicos, tanto la latitud como las condiciones meteorológicas del emplazamiento donde se va a colocar la planta., In this project, an analysis about the latitude’s influence in the sizing of parabolic through collector (PTC) thermosolar plants is carried out. In order to do so, the simulation program System Advisor Model (SAM) processes the meteorological data from clear sky year (CSY) and typical meteorological year (TMY) in different locations. Through a parametrical study, a combination of key parameters in the sizing of a PTC plant is found. These parameters are the ones with which the minimum Levelized Cost of Energy (LCOE) is obtained and, based on them, the influence of latitude and meteorology in the sizing of these types of plants is studied. The results from this work indicate the clear dependence on direct normal irradiance (DNI) when dimensioning solar energy concentration plants. The higher the DNI is, the lower the LCOE is and so are the characteristics of the solar field that are required to make this cost as low as possible. Moreover, the DNI that reaches a site also depends on its latitude, cloudiness and atmospheric turbidity which is also related to the altitude of the site. Among the results from this project, it points out that as latitude increases, the orientation N-S of the collectors loses its advantages over an E-W orientation. It is also observed that meteorology has more influence over the solar multiple if the orientation of the collectors is N-S than if it is E-W. This work establishes the importance of considering when sizing a parabolic through collector solar concentrating plant, both the latitude and the meteorological conditions of the site where the plant will be placed.

El objetivo de este trabajo fin de grado es resumir los procedimientos, métodos y equipos de última generación que se utilizan hoy en día para medir la reflectancia de un espejo en un campo solar de una planta de generación eléctrica.Aunque esa parte sólo cubre aproximadamente el 20% del trabajo, creo firmemente que, para poder hacer un resumen de un estado del arte, es necesario también revisar las bases de este. Por esa razón, el trabajo de investigación ha sido extenso y trata de cubrir la mayoría de los documentos e informes publicados desde la década de 1970 hasta el momento de publicación de este. Se han revisado casi 80 referencias y tal vez algunas de las conclusiones y declaraciones del trabajo podrían entrar en conflicto con el paradigma actual.Este trabajo fin de grado está dirigido a los operadores de plantas que deseen tener una comprensión más profunda de todos los aspectos relacionados con la medición de la reflectancia de los espejos en un campo solar. El trabajo de investigación ha sido extenso y trata de cubrir la mayoría de los documentos e informes publicados desde la década de 1970 hasta el momento de la redacción. Además, los fabricantes de reflectores y sus nuevos productos han sido revisados en esta tesis para dar una visión actual del estado del arte de esta tecnología.Tuve la oportunidad de trabajar fabricando absorbedores solares para plantas con colectores cilindro-parabólicos en una empresa alemana desde 2009 hasta 2015. Por esa razón, tengo un profundo conocimiento de la tecnología de la energía solar de concentración y mi experiencia en un entorno de fabricación intenta dar al trabajo una visión práctica de cómo implementar correctamente la medición de la reflectancia en una planta de energía solar de concentración. Esta tesis de licenciatura ha sido escrita por un novato para principiantes en esta materia con la intención de aprender (yo primero) más sobre cómo la radiación solar llega a la Tierra, cómo se puede "cultivar" para genera, The goalof this Bachelor’s thesis is to resume the state-of-the-art procedures, methods,and equipment used nowadays tomeasure the reflectance of a mirror in a solar field.Although that part only covers roughly 20% of the work, I strongly think that for giving a picture of how it is best to do something, lying the foundations is very important. For that reason,the research work has been extensive and tries to cover most of the papers and reports published from the 1970s to the time of writing. Around90 references have been revised and maybe some of the conclusions and statementsin the work could conflict with the current paradigm. I have tried to state in the work the most updated research and developments.ThisBachelor’sthesis is addressed to plant operators who are willing to have a deeperunderstanding ofall aspects related to the measurement of the reflectance in a solar field. Besides, the manufacturers of reflectometers and their new products have been reviewed in this thesis to give a current vision of the state of the art of this technology.I have been manufacturing solar absorbers for parabolic troughs in a German company from 2009 to 2015. For that reason, I have apiece ofdeep knowledge in Concentrating Solar Power technology and my background in a manufacturing environment gives the thesisa practical vision of how to correctly implementthe measurement of reflectance in a concentrated solar energy plant. This Bachelor’s thesis has been written by a newbie for newbies on such matter with the intention of learning (myselffirst) more about how the solar radiation reaches the Earth, how it can be “farmed” to generate electricity,and how all these tiny littles defects on the mirrors, on the collector, on the foundation, on the sensors, etc. influence the performance of the Solar Thermal Energyplants. This work is organizedas follows. First,the main concepts and terminology related to the reflectance measurement are presented and explained. Next, a detailed descrip

Este proyecto describe el modelado y dimensionamiento de una instalación solar híbrida de tecnología solar térmica de torre y fotovoltaica (CST-PV) en Sevilla, así como una estimación de su producción. Para ello, se realiza un desarrollo teórico de ambas tecnologías describiendo su composición y funcionamiento y se realiza una búsqueda de investigación de las distintas alternativas de centrales híbridas existentes en la actualidad. Así, también se realiza una descripción de la tecnología BLUESOLAR, en la que se basa la central híbrida de estudio. Esta tecnología utiliza filtros ópticos en los captadores de la central, sustituyendo a los heliostatos convencionales, que permiten dividir el espectro solar, para que al mismo tiempo que la placa fotovoltaica genere electricidad, también refleje una parte de la radiación al receptor de la central solar térmica. Además, se realiza un análisis de operación de una central híbrida con esta tecnología, describiendo así los distintos modos y estrategias de operación que puede presentar este tipo de centrales. Por último, se realiza el dimensionamiento, optimización y estimación de la producción e ingresos de la planta de estudio a partir del software System Advisor Model (SAM) y se comparan estos resultados con los de una planta fotovoltaica convencional de igual potencia, The present project treats on the modelize and dimensioning of a hybrid system with concentrated solar power and photovoltaic technologies (CSP-PV) placed in Seville, and an estimation of its production. For that, a theorical development of both technologies will be done, describing the composition and functioning of the system and investigating the different current alternatives of hybrid solar systems. Also, a description of the BLUESOLAR technology, which is the fundamental base of the hybrid system in study, will be done. This technology uses optical filters in the collectors of the solar field, substituting the conventionals heliostats. These optical filters divide the solar spectrum and allow to generate electric energy from the photovoltaic technology while part of the radiation is reflected to the receiver solar of the thermal power plant. After that, an operation analysis of the hybrid installation is developed, describing the different modes and operation strategies which are possible in this type of central. Finally, the dimensioning, optimization and estimation of the production and the incomes of the studied hybrid central are done with the software System Advisor Model (SAM). These results are compared with the ones of a convetional photovoltaic plant with the same power.

CSP feasibility analysis, bankability assessment and plant design are generally based in one-year meteorological series representative of “typical” o extreme conditions. There is a growing interest in accounting on the inherent variability of the performance of solar plants on their input variables in the plant model. In particular, for generating the probability distributions of annual energy yield, simulation tools require as input a large number of plausible meteorological years (PMYs). In this article we generate 100 synthetic years of DNI in the 1-min resolution for the location of Seville, Spain, and we estimate and evaluate the power produced by two CSP plants with similar configuration as two well-known parabolic trough and central receiver solar plants (Andasol 3 and Gemasolar) using System Advisor Model (SAM). We estimate that there is an almost linear relation between the Probabilities of Exceedance (PoE) of the DNI and the gross electricity generation of the solar plants but that for a given annual value that corresponds to a PoE of the DNI, there is a range of possible production values depending mainly on the monthly distribution of the solar radiation datasets.

Laser Ceilometers make use of the elastic LIDAR by emitting signals vertically in the atmosphere and analyzing the profile of the backscattered signal to detect clouds and calculate cloud-base height [1]. Due to the high temporal and vertical resolution, the data provided by the ceilometer is rather useful for solar radiation forecasting or assessing the potential of night radiative cooling of a fluid. To characterize cloudiness, we calculated the cloud occurrence and frequency distribution of cloud-base height in Seville, in a similar way to [2]. Furthermore, we analyze the backscatter signal to obtain a time series, with hourly resolution, of estimated cloud depth and cloud optical thickness that would be useful to determine the effects of clouds on solar radiation and night radiative cooling.

The Variability Index (VI) is widely used to quantify the intra-day solar radiation variability. It compares the length of the global horizontal irradiance (GHI) or direct normal irradiance (DNI) profiles with the length of the corresponding clear sky GHI/DNI profiles. The VI is not a normalized index, it shows dependency on the day of the year, geographic location and time resolution. Thus, the quantification of the intra-day variability of the solar resource between different locations or different seasons could be mistaken. In this work, we propose a novel definition of the VI in order to normalize it (VI’). Moreover, we suggest a methodology to assess the dependencies of the intra-day solar resource variability quantifiers with the day of the year, geographic location and time resolution. We evaluate and compare the performance of both indexes in two different locations along two synthetic years and a measured annual dataset in different time resolutions.

La energía térmica tiene un importante papel en los procesos industriales en la actualidad. Para conseguirla, se recurre a calderas para generar el calor y transferirlo al fluido caloportador del proceso. Esta tarea puede verse auxiliado por la energía solar de concentración que provee energía térmica de calidad y con iguales prestaciones que el calor producido por la caldera. El simulador solar SHIPCal (Solar Heat for Industrial Processes CALculator) es un modelo de uso público desarrollado en lenguaje Python en el que, mediante iteraciones horarias, se analizan los parámetros y prestaciones de un campo solar de concentración integrado en un proceso durante un tiempo determinado de simulación. Actualmente tiene implementado 14 modelos de integración de procesos industriales que se recogen en la guía de integración de la Task 49 de la Agencia Internacional de la Energía: Solar Process Heat for Production and Advanced Applications- Deliverable B2: Integration Guideline. [1] El objetivo de este trabajo es modificar el código fuente de SHIPCal de manera que simule en pasos iterativos de 10 minutos y de 15 minutos para que se puedan conseguir simulaciones más detalladas y precisas respecto a la simulación de paso horario. Por ello es necesario cambiar las distintas funciones del modelo para habilitarlo a leer datos introducidos en formato minutal, calcular los parámetros solares correspondientes y procesarlos para calcular las prestaciones energéticas según el modelo de integración industrial para finalmente generar los correspondientes gráficos e informes. En el trabajo se explica el funcionamiento y estructura de SHIPCal para justificar así los cambios introducidos. Al finalizar las modificaciones, se detallan los resultados obtenidos con ejemplos de simulaciones de un año completo de duración y de un día concreto. También se comparan los resultados y diferencias entre la simulación horaria y la simulación de pasos diezminutales y quinceminutales., Thermal energy plays an important role in industrial processes today. To achieve this, boilers are used to generate heat and transfer it to the heat transfer fluid of the process. This task can be assisted by concentrating solar energy that provides quality thermal energy with the same performance as the heat produced by the boiler. The SHIPCal solar simulator (Solar heat for industrial processes CALculator) is a model for public use developed in Python language in which, by means of hourly iterations, the parameters and performance of a solar concentration field integrated in a process are analyzed for a certain time. simulation. It currently has 14 industrial process integration models implemented which are included in the integration guide of Task 49 of the International Energy Agency: Solar process heat for production and advanced applications - Deliverable B2: Integration guideline [1]. The objective of this work is to modify the source code of SHIPCal so that it simulates in iterative steps of 10 minutes and 15 minutes so that more detailed and precise simulations can be achieved with respect to the time step simulation. For this reason, it will be necessary to change the different functions of the model to enable it to read data entered in minute format, calculate the corresponding solar parameters and process them to calculate the energy performance according to the industrial integration model to finally generate the corresponding graphs and reports. The project explains the operation and structure of SHIPCal, as well as the changes introduced. At the end of the modifications, the results obtained are detailed with examples of simulations lasting a full year and on a specific day. The results and differences between the hourly simulation and the simulation of ten-minute and fifteen-minute steps are also compared.

En este TFG se realiza el diseño y dimensionado de una instalación híbrida fotovoltaica-hidrógeno con el fin de satisfacer la demanda energética de una vivienda. Se cubre tanto la demanda eléctrica como la térmica, dentro de la cual se consideran las de ACS (agua caliente sanitaria), calefacción y refrigeración. La demanda eléctrica se define en base al historial de consumo de la propia vivienda y la demanda térmica se calcula en base al CTE (Código Técnico de la Edificación) y a las características arquitectónicas de la edificación y usando el método de cálculo empleado por Encinas en su TFG (2019) —con ciertas modificaciones—. Una vez definidas las demandas, se procede al diseño y dimensionado de la instalación. Inicialmente se dimensiona la instalación para que la vivienda sea autosuficiente y pueda no estar conectada a la red eléctrica, y posteriormente se dimensiona para que la vivienda tenga un balance económico anual de la energía nulo. En este segundo caso la vivienda sí estaría conectada a la red. Una vez realizados los dimensionados, se procede al análisis energético de ambos casos y seguidamente se exponen los resultados más significativos y sus conclusiones., The present Final Degree’s Work shows the designing and sizing process for a photovoltaic-hydrogen hybrid system to supply the energy demand of a dwelling, both electric and thermal energy demand. The last one includes DHW (domestic hot water), heating and refrigeration. The electric demand is defined by the historical consumption of the dwelling. The thermal demand is calculated according to the CTE (a Spanish building law) and the architectonic characteristics of the building and using the method employed by Encinas in his Final Degree’s Work (2019)—with certain changes—. Once the demand is defined, the design has been made and the dimension of the system calculated. Firstly, the dimension has been calculated to gain a self-sufficient dwelling (thus it would not be necessary to be connected to the electricity grid) and,secondly, it has been calculated to reach a zero economic annual balance of the energy (in this case, the electricity grid connection would be necessary). Finally, after calculating the dimensions, the energetic analysis has been made in both cases, and a summary of the main results and their conclusions are shown.

Stand-alone photovoltaic systems usually use batteries to adjust energy yield to energy demand. An alternative energy storage system for stand-alone photovoltaic installations is proposed for three cooling applications: air conditioning, food preservation and freezing. A thermally insulated storage tank with ammonia in saturated mixture phase is integrated into the vapour-compression cooling cycle. A thermodynamic model and an economic assessment based on typical costs and cost sensitivity are included to assess the proposed system performance in comparison with a conventional stand-alone photovoltaic system with a vapour-compression cycle. Results show that the proposed storage strategy is an affordable option, especially in hot climates and for food preservation and freezing applications.

The operation and the electricity yield of CSP plants in two days with the same daily-accumulated DNI, even with the same Aperture Normal Irradiance (ANI) can be very different depending on other parameters such as the variability and distribution of the solar radiation. In this paper, we intend to quantify the impact of the intra-daily variability of the DNI on the production of CSP plants. To that end, we use the ND model [1] to generate several synthetic years with similar distribution and daily energy to a reference measured year but different levels of intra-daily variability. We use System Advisor Model (SAM, https://sam.nrel.gov/) to simulate the performance of two parabolic trough (PT) plants, with and without thermal storage and common configurations for the location of Seville, Spain. To test the influence of the DNI variability, we simulate the measured and the synthetic years and we compare the daily gross power produced. As result, a clear decrease in the gross production of the PT plant without TES system is observed when the intra-daily variability increases, with daily average differences of 47% respect to the case with lowest variability. This difference is reduced with the use of the TES system to 6 %, damping the dynamic effects of the DNI variability on the global response of the plant.