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[ES] El sector industrial es responsable de una cantidad significativa de emisiones anuales de carbono, en gran parte debido a su elevado consumo de energía y a su dependencia de los combustibles fósiles para la producción de calor. Por tanto, es evidente que la utilización de fuentes de calor alternativas y renovables, como los colectores solares de concentración, representa una oportunidad prometedora para la descarbonización de este sector. Sin embargo, los sistemas de colectores solares dependen del recurso solar, que es una fuente de energía intermitente. Por ello, es necesario disponer de un sistema de almacenamiento de energía térmica (AET) que facilite el almacenamiento de la energía sobrante y su posterior utilización cuando sea necesario, garantizando así un suministro de calor más constante. Con el fin de demostrar la viabilidad de los sistemas solares térmicos para aplicaciones industriales, la empresa Solatom CSP instaló un campo solar experimental dentro del proyecto SOLPINVAP. Está compuesto por una serie de colectores modulares lineales Fresnel (CLF) y un kettle reboiler, que es un tipo de intercambiador de calor de carcasa y tubos. Esta tesis analiza el rendimiento del sistema en modo de generación indirecta de vapor. En este modo, el calor se absorbe en el interior de los tubos absorbedores mediante un fluido caloportador y se transfiere a la carcasa del kettle reboiler, donde se produce vapor. Además, esta tesis examina los circuitos hidráulicos y sus componentes del campo solar experimental, así como el sistema de control y el sistema de monitorización asociados al mismo. Además, se presenta el desarrollo de un modelo de sistema CLF de calor solar para procesos industriales (CSPI). El modelo se desarrolló en el entorno MATLAB orientado a objetos. Se desarrolló un modelo 3D del campo solar CLF dentro del entorno Tonatiuh (un software de trazado de rayos), lo que permitió estimar la eficiencia óptica máxima y los correspondientes modificadores del ángulo de incidencia de los colectores Fresnel. Los resultados demuestran que el calor absorbido en los colectores presenta una incertidumbre del 12%, mientras que el calor generado presenta una incertidumbre del 3%. Para reducir la incertidumbre inherente al cálculo del calor absorbido y generado, se realizó un estudio para seleccionar sensores y equipos de monitorización más precisos. Además, se realizó un trabajo de campo para instalar los equipos seleccionados, más precisos, en el campo solar SOLPINVAP. Los resultados de la monitorización demuestran que la incertidumbre en el calor absorbido se redujo en un 79% como consecuencia de la mejora en la instrumentación de medida. Como parte de este proyecto de tesis, se realizó una estancia de investigación en el Departamento de Ingeniería de Mecánica y Metalúrgica de la Pontificia Universidad Católica de Chile, en Santiago. El equipo de investigación anfitrión ha estado investigando la posible aplicación de AET de lecho compacto sólido con escoria de cobre, un subproducto del proceso pirometalúrgico del mineral de cobre, como medio de almacenamiento. Además, el equipo de investigación ha desarrollado un modelo matemático que simula el proceso termodinámico y de transferencia de calor asociado al flujo de aire y a las partículas sólidas. En consecuencia, el modelo del sistema de AET de lecho compacto sólido se ha integrado en el modelo del sistema CSPI para examinar su efecto en el rendimiento del sistema. Además, esta tesis examina la dinámica entre las temperaturas de los distintos componentes del sistema. En consecuencia, esta tesis presenta un diseño para un sistema integrado CSPI con AET de lecho compacto sólido. Los resultados demuestran que el sistema con el AET de lecho compacto sólido es capaz de generar un 18% más de energía que el sistema sin el AET de lecho compacto sólido. [CA] El sector industrial és responsable d'una quantitat significativa d'emissions anuals de carboni, en gran part a causa del seu alt consum d'energia i la dependència dels combustibles fòssils per a la producció de calor. Per tant, és evident que la utilització de fonts de calor alternatives i renovables, com la concentració de col·lectors solars, representa una oportunitat prometedora per a la descarbonització d'aquest sector. No obstant això, els sistemes de col·lectors solars depenen del recurs solar, que és una font d'energia intermitent. Per tant, és necessari disposar d'un sistema d'emmagatzematge d'energia tèrmica (TES) per facilitar l'emmagatzematge de l'energia sobrant i la seva posterior utilització quan sigui necessari, assegurant així un subministrament de calor més consistent. Per tal de demostrar la viabilitat dels sistemes solars tèrmics per a aplicacions industrials, l'empresa Solatom CSP va instal·lar un camp solar experimental dins del projecte SOLPINVAP. Comprèn una sèrie de col·lectors lineals modulars de Fresnel i un Kettle Reboiler, que és un tipus d'intercanviador de calor de carcassa i tubs. Aquesta tesi analitza el rendiment del sistema en mode de generació de vapor indirecte. En aquest mode, la calor s'absorbeix a l'interior dels tubs absorbents mitjançant l'ús d'un fluid de transferència de calor, i es transfereix a la capa del Reboiler, on es produeix vapor. A més, aquesta tesi examina els circuits hidràulics i els seus components del camp solar experimental, així com el sistema de control i el sistema de monitoratge associat a aquest. A més, es presenta el desenvolupament d'un model de sistema LFC per a processos industrials (SHIP). El model es va desenvolupar dins de l'entorn MATLAB orientat a objectes. Es va desenvolupar un model 3D del camp solar LFC dins de l'entorn Tonatiuh (un programari de rastreig de raigs), que permet estimar l'eficiència òptica màxima i els corresponents modificadors d'angle d'incidència dels col·lectors Fresnel. Els resultats demostren que la calor absorbida en els col·lectors mostra una incertesa del 12%, mentre que la calor generada mostra una incertesa del 3%. Per tal de reduir la incertesa inherent al càlcul de la calor absorbida i generada, es va realitzar un estudi per seleccionar sensors i equips de monitoratge més precisos. A més, es va realitzar un treball de camp per a instal·lar els equips seleccionats i més precisos en el camp solar SOLPINVAP. Els resultats de seguiment demostren que la incertesa en la calor absorbida es va reduir en un 79% com a conseqüència de la millora en la instrumentació de mesura. En el marc d'aquest projecte de tesi, es va realitzar una estada de recerca al Departament d'Enginyeria de Mecànica i Metalúrgica de la Pontifícia Universitat Catòlica de Xile, a Santiago. L'equip d'investigació amfitrió ha investigat la potencial aplicació de PBTES sòlids amb escòria de coure, un subproducte del procés pirometal·lúrgic del mineral de coure, com a medi d'emmagatzematge. A més, l'equip d'investigació ha desenvolupat un model matemàtic que simula el procés de transferència de calor i termodinàmica associat al flux d'aire i les partícules sòlides. En conseqüència, el model del sistema PBTES s'ha integrat en el model del sistema SHIP per a l'examen del seu efecte sobre el rendiment del sistema. A més, aquesta tesi examina la dinàmica entre les temperatures dels diferents components del sistema. En conseqüència, aquesta tesi presenta un disseny per a un sistema solar integrat amb sistema PBTES. Els resultats demostren que el sistema amb el PBTES és capaç de generar un 18% més d'energia que el sistema sense el PBTES. A més, es va dur a terme una anàlisi tecnoeconòmica utilitzant el sistema SHIP dissenyat amb PBTES. [EN] The industry sector is responsible for a significant amount of annual carbon emissions, largely due to its high energy consumption and reliance on fossil fuels for heat production. It is therefore evident that the utilisation of alternative and renewable heat sources, such as concentrating solar collectors, represents a promising opportunity for the decarbonisation of this sector. Nevertheless, solar collector systems are dependent on the solar resource, which is an intermittent source of energy. It is therefore necessary to have a thermal energy storage (TES) system to facilitate the storage of surplus energy and its subsequent utilisation when required, thereby ensuring a more consistent heat supply. In order to demonstrate the viability of solar thermal systems for industrial applications, the company Solatom CSP installed an experimental solar field within the SOLPINVAP project. It comprises a series of modular linear Fresnel collectors (LFC) and a kettle reboiler, which is a type of shell and tube heat exchanger. This thesis analyses the performance of the system in Indirect Steam Generation mode. In this mode, heat is absorbed inside the absorber tubes by using a heat transfer fluid, and transferred to the shell of the kettle reboiler, where steam is produced. Additionally, this thesis examines the hydraulic circuits and their components of the experimental solar field, as well as the control system and the monitoring system associated with it. Moreover, it is presented the development of a LFC solar heat for industrial process (SHIP) system model. The model was developed within the object-oriented MATLAB environment. A 3D model of the LFC solar field was developed within the Tonatiuh environment (a ray-tracing software), allowing for an estimation of the peak optical efficiency and the corresponding incidence angle modifiers of the Fresnel collectors. . The results demonstrate that the absorbed heat in the collectors exhibits an uncertainty of 12%, while the generated heat exhibits an uncertainty of 3%. In order to reduce the uncertainty inherent in the calculation of the absorbed and generated heat, a study was conducted to selected more precise sensors and monitoring equipment. Moreover, fieldwork was conducted to install the selected, more precise equipment at the SOLPINVAP solar field. The monitoring results demonstrate that the uncertainty in the absorbed heat was reduced by 79% as a consequence of the improvement in the measurement instrumentation. As part of this thesis project, a research stay was conducted at the Departamento de Ingeniería de Mecánica y Metalúrgica of the Pontificia Universidad Católica de Chile, in Santiago. The host research team has been investigating the potential application of solid PBTES with copper slag, a by-product of the pyrometallurgical process of the copper ore, as a storage medium. Moreover, the research team has developed a mathematical model that simulates the thermodynamic and heat transfer process associated with the airflow and solid particles. Accordingly, the PBTES system model has been integrated into the SHIP system model for examination of its effect on the system performance. Furthermore, this thesis examines the dynamics between the temperatures of the different system components. Consequently, this thesis presents a design for an integrated SHIP with PBTES system. Moreover, it was determined that by modifying the air mass flow and the makeup water flow, the system is capable of maintaining a consistent and uninterrupted heat output throughout the operational duration. The results demonstrate that the system with the PBTES is capable of generating 18% more energy than the system without the PBTES. I would like to thank the Universitat Politècnica de València through the Research and Development Aid Program (PAID-01-20) for receiving the Research Fellowship FPI-UPV-2020. I would also like to acknowledge the "Programa de Movilidad para estudiantes de doctorado" of the Universitat Politècnica de València for providing financial support for my research stay.

AbstractThis study investigates the potential recognition and engagement of the natural environment as an important factor in strategic investment decisions by accommodation suppliers in a small island context. The investigation, based on empirical data from two Thai islands, Koh Tao and Koh Phi Phi, contributes to the debate if the environment, by focusing on climate change, can be identified as a primary stakeholder for accommodation suppliers. The findings show that strategic investment decisions are influenced by impacts commonly associated with climate change, although a conscious recognition of climate change as a strategic stakeholder or important factor in strategic investment decisions could not be confirmed. Conversely, the element of unconsciousness in the process of recognising climate change in investment decisions sparks questions regarding the degree to which the recognition of business stakeholders requires being a conscious process and if the focus on investments could be another element for stakeholder identification frameworks for businesses.

The work of N. Mignoni was supported by the Italian Ministry of University and Research under the National Operating Programme for Research and Innovation 2014-2020, Action IV.5, Decree no. 1061/2021. J. MartinezPiazuelo gratefully acknowledges the Universitat Polit` ecnica de Catalunya and Banco Santander for the financial support of his predoctoral grant FPIUPC. The work of R. Carli was supported by the Apulia Region (Italy) under the Research for Innovation (REFIN) Call (Project no. C9A3735B). The work of J. Martinez-Piazuelo and C. Ocampo-Martinez was supported by the project PID2020-115905RB-C21 (L-BEST) funded by MCIN/ AEI /10.13039/501100011033. The work of N. Quijano was supported by the project BPIN 2021000100499, funded by CTeI- SGR and Minciencias, Colombia. The work of M. Dotoli was supported in part by the European Union Next-GenerationEU (National Recovery and Resilience Plan (NRRP), Mission 4 Component 2 Investment 1.3) under the NEST (Network 4 Energy Sustainable Transition) Extended Partnership (Italian Ministry of University and Research Decree no. 1561/2022, project no. PE00000021). Under the umbrella of non-cooperative game theory, we formulate a transactive energy framework to model and control energy communities comprised of heterogeneous agents including (yet not limited to) prosumers, energy storage systems, and energy retailers. The underlying control task is defined as a generalized Nash equilibrium problem (GNEP), which must be solved in a distributed fashion. To solve the GNEP, we formulate a Gauss-Seidel-type alternating direction method of multipliers algorithm, which is guaranteed to converge under strongly monotone pseudo-gradient mappings. As such, we provide sufficient conditions on the private cost and energy pricing functions of the community members, so that the strong monotonicity of the overall pseudo-gradient is ensured. Finally, the proposed framework and the effectiveness of the solution method are illustrated through a numerical simulation. © 2024 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. Peer Reviewed

El propòsit de la tesi va ser explorar mitjançant estudis empírics l'evolució de l'ús de les eines Lean a les empreses manufactureres europees i el seu vincle amb les tecnologies de la Indústria 4.0 i les pràctiques green. En primer lloc, es va investigar l'adopció i la internalització de les eines Lean i el seu impacte en el rendiment productiu a les empreses manufactureres espanyoles. Tot seguit, es va analitzar la influència de la internalització de les eines Lean en l'adopció de tecnologies de la Indústria 4.0 a les empreses manufactureres europees. I, finalment, es va examinar la relació entre l'ús conjunt d'eines Lean i les pràctiques green associat a l'exercici mediambiental a les empreses manufactureres espanyoles. La metodologia emprada al llarg dels estudis presentats es va basar en l'anàlisi de dades extretes de la European Manufacturing Survey The purpose of the thesis was to explore through empirical studies the evolution of the use of lean tools in European manufacturing firms and their link with Industry 4.0 technologies and green practices and Circular Economy. First, the adoption and internalisation of lean tools and their impact on production performance in Spanish manufacturing firms were investigated. Next, the influence of the internalisation of Lean tools on the adoption of Industry 4.0 technologies in European manufacturing firms was analysed. Finally, the relationship between the joint use of Lean tools and green practices associated with environmental performance in Spanish manufacturing firms was examined. The methodology employed throughout the studies presented was based on the analysis of data extracted from the European Manufacturing Survey Programa de Doctorat Interuniversitari en Dret, Economia i Empresa

Renewable energy projects, such as wind farms and hydropower dams, can indirectly benefit biodiversity by mitigating climate change. However, we explain why such indirect benefits should not contribute towards the accounting of project-level net biodiversity outcomes and provide guidance on the steps needed to legitimately claim no-net-loss of biodiversity.

The rapid growth of photovoltaic (PV) technology in recent years called for a comprehensive assessment of the global scientific landscape on fires associated with PV energy installations. This study examines the scientific literature indexed in Scopus from 1983 to 2023. It reveals a striking increase in output since 2011, with nearly one hundred publications in the most recent year under review. This growth of interest has occurred in parallel with the global expansion of photovoltaics. The majority of studies in this field are classified as engineering, with 34% of publications in this area. The USA leads the way with over 160 publications, followed by China with 125. Two institutions in the USA are particularly prominent in this field: Sandia National Laboratories in New Mexico with 22 publications, and the National Renewable Energy Laboratory in Colorado with 16 publications. The second institution is the University of Science and Technology of China, which has published 17 articles on the subject. A close examination of the evolution of keywords reveals a remarkable transformation in the scientific landscape over the past 10 years, from 2013 to 2023. The evolution of keywords suggests a maturation in the understanding of fire risks associated with photovoltaic energy. A total of seven scientific communities have been identified in which these works are grouped according to their keywords. These include Fire and Energy Storage, PV faults, Fire resistance, Fire hazard, Fire detectors, Deep learning, and Fire safety. It has been found that fires caused by PV installations are not listed as a cause of fire starts. This should be taken into account when conducting preventive analyses of this potential danger, particularly in light of the possible development of agrivoltaics, where facilities will be mainly located in the natural environment. Embargado hasta 19/05/2026

This document presents a qualitative analysis of surface temperatures of the oceanic territory of Panama. These temperatures represent an indication of the potential of the thermal resource in the oceanic territory of Panama and could generate benefits for the success and stability of the national economy facing the current and growing challenges of the society. The OTEC technology is promising for countries located in tropical regions, where sea temperature differentials are ideal for efficient operability. Currently, this technology has low efficiency levels. Therefore, to evaluate its possible implementation in Panama, a theoretical thermodynamic analysis has been carried out. An organic Rankine cycle (ORC) simulation for the net production of 100KW was performed. It considered the temperature differentials of the oceanography of Panama and used refrigerants R717 and R134a as working fluids. Considering the database of Physical Oceanography Distributed Active Archive Center (PODAAC) for the year 2018, the ocean territory of Panama in the Gulf of Chiriqui reflects seawater surface temperatures (SST) of approximately 27.5 °C to almost 29.5 °C. Besides these values they do not reflect representative anomalies in the critical points with respect to the seasons of the year. The importance of the study in this area is its proximity to the deep cold sea waters, considering the Panama bathymetry map, since its SST are not very variable through the year or through the territory?

Abstract The analysis of a large amount of data on the failures of absorption refrigeration machines of the ammonia-water type was carried out. The data derive from the records of a 10-year maintenance contract under which every machine was installed. The records were computerized for the period 1989–1992, and they refer to sales starting from 1980 (i.e. to 73 778 machines). The failures are classified, identifying the most serious (generator and solution pump). The rate of early failures is rather high, but the failures are generally minor and easily repaired. The production quality was not constant, with a very bad year in 1984. The failure rate is evaluated for the first 10 years of life of the equipment. In general terms, one machine in two does not require any intervention during that period.