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This paper presents the application of a probabilistic multi-stability assessment of a modified two-area system under the presence of low and high uncertainty sources. The stability of the network is assessed under four stability regimes: frequency, small-signal rotor angle, large-signal rotor angle, and long-term voltage. The probabilistic assessment is carried out using Monte Carlo simulation. Two cases considering low and high uncertainty are investigated. The obtained results are presented in the form of parallel coordinate plots so that the interaction between multiple stability regimes can be more easily understood. It is observed that the poor response of small-signal rotor angle stability generally corresponds to poor response of other stability types in low uncertainty case. However, once the level of uncertainty increases and more sources of uncertainty exist, this relationship is significantly changed.

Three modules are integrated into the built-in OpenFOAM rhoCentralFoam solver towards accurate and efficient modelling of high-speed chemically reactive flows in two-phase gas-droplet mixtures within the OpenFOAM 10.0 framework. The first module is the mixture-averaged diffusion model. The second module is the built-in OpenFOAM Lagrangian solver coupled with optimised droplet drag coefficient and convective heat transfer coefficient sub-models. The last module is a sparse stiff chemistry solver based on dynamic adaptive hybrid integration (AHI-S). The optimised droplet sub-models are first verified in correct implementation for subsequent simulations in this work. They show good accuracy against experimental and analytical data in the modelling of ammonia droplet acceleration and cooling in the flowing and/or low-temperature air. The accuracy and efficiency gains related to the mixture-averaged diffusion model and the AHI-S chemistry solver are examined by simulating 1-D detonation propagation in ammonia droplet-free/laden ammonia-oxygen mixtures. Numerical results of detonation propagation speed, gaseous temperature, density, and species distributions around the induction zone show good agreement with experimental data and analytical solutions. Compared to the built-in OpenFOAM diffusion model, the mixture-averaged diffusion model provides different numerical predictions of pulsating instabilities in detonation propagation. It shows better accuracy in depicting the detonation structure within the droplet-free section attributed to improved multi-component diffusion modelling. Compared to the built-in OpenFOAM solver EulerImplicit (backward Euler), the AHI-S chemistry solver reduces the computational cost by around 50%. It achieves satisfactory accuracy in calculating detonation propagation speed within the droplet-free section with the optimal efficiency when the safety factor, β, equals 0.5.

The aim of this study is to define strategies to increase green nuclear energy investments. Within this context, a model is suggested that includes two different stages. Firstly, the consensus-based fuzzy preferences are determined for these investments. For this purpose, four different TRIZ-based strategies are identified, which have an influence on the effectiveness of these projects. Furthermore, in the second stage, the significance weights of these strategies are calculated by considering the spherical fuzzy DEMATEL approach. The findings indicate that dynamicity is the most appropriate TRIZ strategy for the effectiveness of green nuclear energy investments. In addition, the prior action is another significant strategy that should also be considered in these projects. It is obvious that sufficient technological infrastructure is very important for the performance of green nuclear power plants and there is a rapid development of this technology. Because of this situation, these nuclear power plants should be designed effectively so that they can be adoptable to any changes in the technology. In this scope, qualified personnel should be employed, and communication between departments should be effective and of high quality. With the help of these issues, technological changes can be adopted more easily.

Some Parties (Countries) to the UNFCCC decided to include the carbon uptake by harvested wood products (HWP) in a new general accounting framework after 2012 (post Kyoto). The analysis aims to make a comparison between the cascaded use of HWP and the use of wood for energy. We combine the new HWP framework with an assumed increased 50 million m3harvest level in Canada and evaluate the impact of the GHG emissions over a 100-year period. Our reference case assumes all harvested wood is an immediate CO2emission (IPCC default) and no substitution effects, i.e. annual GHG emissions of 41 million tonnes CO2eq. In our wood utilization scenario's, harvested trees are allocated (in varying shares) to three end-products: construction wood, paper products and pellets for power production. In comparison with our base case, a combination of fossil fuel substitution, material substitution and temporary carbon uptake by HWP leads to significant decreases in GHG emissions. All scenario's show annual GHG emission between 18 and 21 million tonnes CO2eqexcept for triple use without recycling (at least 24 million tonnes CO2eq). We conclude that GHG emissions of our scenarios are substantially lower than IPCC default. However, it is difficult to incorporate one single method to account for GHG uptake and emissions by HWP, due to end use efficiency and recycling options. Further GHG allocation over individual countries is not straightforward and needs further research. © 2013 Elsevier Ltd.

Digitalization trends in building management increasingly emphasize the creation of Digital Twins (DTs) for building management but often neglect how occupants interact with these technologies. This paper aims to explore the functionalities of building management systems based on occupant interactions with DTs. To achieve this, occupant preferences are investigated through a questionnaire survey conducted with 106 respondents from two case studies. The survey investigated participants’ interest in using DTs for various building management tasks, their familiarity with DTs and their demographic factors. Analysis results revealed that occupant’s interest in DTs is not significantly influenced by their prior knowledge or gender. Instead, providing access to DTs increased their interest in areas beyond their job roles, particularly in aspects related to comfort and environmental management. Younger participants showed a heightened interest in using DTs for environmental and energy management issues. The study also suggests that promoting occupant interaction with DTs can enhance productivity and satisfaction. This paper underscores the need for additional research to integrate smart technologies into building management with a focus on occupant involvement. It highlights the potential of DTs to improve real-time monitoring and support sustainability initiatives and thus, offers a more inclusive and effective alternative to traditional management tools. This work was supported by the Association Nationale de la Recherche et de la Technologie (ANRT) under the Grant CIFRE 2017/1782. Peer Reviewed

[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.

Abstract This work focuses on the efforts being made by King County, Washington to respond to the challenges of global climate change, concentrating on both mitigation and adaptation. King County is a leader in the United States in the development and implementation of meaningful climate change efforts in local government. The county, in conjunction with ICLEI, recently produced a workbook on Preparing for Climate Change at the Local, Regional, and State levels. While the vast majority of local governments in the United States have only taken limited steps to respond to global warming, King County stands out as aggressively looking to move in a new direction. The King County Climate Plan is based on the conviction that climate change is both a problem and an opportunity for communities to improve environmental quality through mitigation of greenhouse gases and simultaneously build resilience to adapt to global climate change. Its exceptional combination of responsibilities in planning and opportunities makes this an invaluable experience to other local governments throughout the world. The work to be presented is a case study that examines the underlying issues and challenges faced by this jurisdiction in adopting its climate change plan; the development and adoption of the plan; issues associated with monitoring and sustaining these efforts; and the broader challenges of building more resilient and adaptive communities. The case study will focus both on procedural issues, as well as, on the types of mitigation and adaptive responses. One aspect of the paper will examine King County's efforts to link climate change efforts/policy/plans to other critical community concerns (e.g., issues of equity and race), and to the economic opportunities that have become critical motivators to successfully as moving forward the county attempts to establish itself as a global leader in meeting the challenges of global climate change.