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The utilisation of thermoelectric technology as a heat pump in heating applications necessitates comprehensive investigation. The scalable nature of thermoelectric technology enables its operation at elevated temperatures without the requirement of refrigerants. In this work, an accurate computational model that can simulate one- and two-stage thermoelectric heat pumps is developed. This model uses the electric-thermal analogy and the finite difference method, including the thermoelectric effects, temperature dependent properties, thermal contact resistances and all heat exchangers, even the intermediate heat exchanger in the case of a two-stage configuration. Moreover, the model has been experimentally validated by built and tested prototypes, being the first time that a two-stage thermoelectric heat pump model is experimentally validated. The discrepancy between the simulated and experimental results is below the ± 10 % for , ± 8 % for generated heat and temperature lift in the airflow, and less than the ± 6 % for consumed power. Additonally, the model simulates real tendencies under different operating conditions, proving the reliability of the developed thermoelectric heat pump model. Finally, the model is used to optimise a thermoelectric system combining one- and two-stage thermoelectric heat pumps, and hybridising them with electric resistances. An airflow of 16.5 m3/h is heated from 25 °C to 160 °C, achieving a maximum of 1.21. Lastly, the importance of considering the thermal resistances of the heat exchangers is computationally modelled and demonstrated. Not taking them into account would overestimate the performance of the TEHP system by more than the 7 %. The authors would like to acknowledge the support of the grant TED2021-130071A-I00 funded by MCIN/AEI/10.13039/501100011033 and, as appropriate, by 'European Union Next Generation EU/PRTR', as well as the Government of Navarre, as part of the 'Grants to SINAI agents for the realization of collaborative R&D projects' under the PC066-067-068 FlexORCStorage. Open access funding provided by Universidad Pública de Navarra.

Using a combination of numerical and analytical techniques we demonstrate that a metal stripe surrounded by the active and passive dielectrics supports propagation of stable spatial surface-plasmon solitons. Our analytical methods include the multiple scale reduction of the Maxwell's equations to the coupled Ginzburg-Landau system, and the soliton perturbation theory developed in the framework of the latter.

The SBE19 Brussels - BAMB-CIRCPATH "Building as Material Banks - A Pathway for a Circular held in Brussels on 5 to 7 of February 2019, is an initiative of the Consortium of the H2020 BAMB Project together with the Sustainable Built Environment (SBE) series of conferences. Being within the SBE series, this event gathers the support of CIB International Council for Research and Innovation in Building and Construction, iiSBE International Initiative for a Sustainable Built Environment, the United Nations Environment Programme, and FIDIC International Federation of Consulting Engineers. The goal of this series of regional and international conferences is to disseminate innovative policies and developments in the field of sustainable urban environment to a broad international audience of specialists in policy, design, construction and operation of buildings and related infrastructure. info:eu-repo/semantics/publishedVersion

Electrolyte imbalance caused by the undesired vanadium-ions cross-over and water transport through the membrane is one of the main critical issues of vanadium redox flow batteries, leading to battery capacity loss and electrolytes volume variation. In this work, the evolution of discharged capacity and electrolyte volume variation were firstly investigated adopting commercial electrolyte for hundreds of charge-discharge cycles in vanadium redox flow batteries employing different membranes, varying thickness and equivalent weight. Subsequently, with the support of a 1D physics-based model, the origin of the main phenomena regulating capacity decay and volume variation has been identified and different modifications in the preparation of electrolytes have been proposed. Electrolytes characterized by an equal proton concentration between the two tanks at the beginning of cycling operation turned out to limit capacity decay, while increasing electrolyte proton concentration was effective also in the mitigation of volume variation. The most promising electrolyte preparation combined the effect of high proton concentration and null osmotic pressure gradient between the two tanks: compared to commercial electrolyte this preparation reduced the capacity decay from 47.7% to 20.9%, increased the coulombic efficiency from 96.2% to 98.9% and the energy one from 79.9% to 83.4%, and also implied a negligible volume variation during cycles. The effectiveness of this electrolyte preparation has been verified with different membranes, increasing the range of validity of the results, that could be thus applied in a real system regardless of the adopted membrane.

Esta dissertação investiga a implementação de uma plataforma tecnológica para monitorar métricas (Environmental, Social, and Governance - ESG) 1 no sector energético, com foco na Galp Energia, uma das principais empresas do sector em Portugal. Este estudo é motivado pela necessidade de a empresa cumprir as rigorosas exigências impostas pela nova Corporate Sustainability Reporting Directive (CSRD)2 da União Europeia. A plataforma adotada tem como objetivo centralizar e automatizar a gestão dos dados ESG, esperando melhorias na precisão, transparência e conformidade dos relatórios. A pesquisa baseia-se numa revisão de literatura que sustenta a realização de sete entrevistas com os principais responsáveis pela implementação do projeto, bem como com os futuros utilizadores da nova plataforma. Estas entrevistas são complementadas por uma análise documental fornecida pela Galp, incluindo informação detalhada sobre o processo de seleção e desenvolvimento da plataforma, relatórios institucionais e outras fontes disponíveis na internet. Da revisão de literatura aprende-se que os desafios da implementação de uma plataforma tecnológica para gestão de ESG são: a integração de dados provenientes de múltiplas fontes, a complexidade da adaptação organizacional e a necessidade de garantir a coerência entre as práticas operacionais e os requisitos regulatórios. Por outro lado, os benefícios incluem uma maior eficiência operacional, redução de custos associados à monitorização dos indicadores ESG e um fortalecimento da capacidade da empresa em gerir a sustentabilidade de forma holística e integrada. Embora a utilização de plataformas tecnológicas para a gestão de métricas ESG seja um fenómeno relativamente recente, há uma crescente quantidade de literatura que explora os seus benefícios e desafios. Contudo, devido à novidade do tema, ainda existe uma carência de bibliografia mais consolidada que permita uma análise aprofundada e abrangente do impacto destas soluções no longo prazo. Esta lacuna reforça a relevância do presente estudo, que visa contribuir para o corpo de conhecimento existente, oferecendo uma visão prática e detalhada da implementação de uma plataforma ESG numa empresa do sector energético. O estudo de caso permitiu concluir que a adoção da plataforma tecnológica poderá resultar em melhorias significativas na capacidade da Galp Energia de cumprir as exigências regulatórias e de apresentar relatórios ESG mais completos e precisos. Além disso, a utilização de uma ferramenta centralizada, se bem-sucedida após a sua implementação, poderá proporcionar uma maior agilidade na tomada de decisões estratégicas, com base em dados fiáveis e em tempo real, contribuindo para a consolidação da posição da Galp como líder em sustentabilidade no sector energético. This dissertation investigates the implementation of a technological platform for monitoring Environmental, Social, and Governance (ESG) metrics in the energy sector, focusing on Galp Energia, one of the leading companies in the sector in Portugal. This study is motivated by the need for the company to comply with the stringent requirements imposed by the European Union's new Corporate Sustainability Reporting Directive (CSRD). The adopted platform aims to centralize and automate the management of ESG data, with the expectation of improving the accuracy, transparency, and compliance of reports. The research is based on a literature review that supports seven interviews with key personnel responsible for the project’s implementation and future users of the platform, complemented by a documentary analysis provided by Galp. This documentation includes information on the selection and development process of the platform, institutional reports, and publicly available online sources. From the literature review, it is learned that the challenges of implementing a technological platform for ESG management include the integration of data from multiple sources, the complexity of organizational adaptation, and the need to ensure consistency between operational practices and regulatory requirements. On the other hand, the benefits include increased operational efficiency, reduced costs associated with monitoring ESG indicators, and enhanced company capacity to manage sustainability in a holistic and integrated manner. Although the use of technological platforms for managing ESG metrics is a relatively recent phenomenon, there is a growing body of literature that explores its benefits and challenges. However, due to the novelty of the subject, there remains a lack of more consolidated bibliographical sources that allow for a comprehensive and in-depth analysis of the long-term impact of these solutions. This gap underscores the relevance of the present study, which aims to contribute to the existing body of knowledge by offering a practical and detailed view of the implementation of an ESG platform in an energy company. The case study concluded that the adoption of the technological platform could result in significant improvements in Galp Energia's ability to meet regulatory requirements and produce more comprehensive and accurate ESG reports. Furthermore, the use of a centralized tool, if successfully implemented, could provide greater agility in strategic decision-making, based on reliable and real-time data, contributing to consolidating Galp's position as a leader in sustainability within the energy sector. info:eu-repo/semantics/publishedVersion

[ES]Se ha elaborado una nueva base de datos de precipitaciones medias mensuales y temperaturas máximas y mínimas medias mensuales, con la que se han analizado los datos de 142 estaciones meteorológicas obtenidos de la Agencia Estatal de Meteorología (AEMET) para el periodo (1989-2018). En este estudio se presentan los resultados de diferentes pruebas de homogeneización y relleno de 134, 172 y 176 series de temperaturas y precipitaciones provenientes de las estaciones ubicadas en la región de Extremadura. Para ello, se realizó un primer control de calidad de los datos cumpliendo con los requisitos de la Organización Meteorológica Mundial (OMM) y las recomendaciones indicadas por el Real Instituto Meteorológico de los Países Bajos (KNMI). Posteriormente se llevó a cabo la homogeneización de las series utilizando el software Climatol, en el que se han implementado diferentes funciones que permiten depurar los datos a través de un análisis de los valores atípicos y de la homogeneidad, así como la completación de las lagunas de las series. Los análisis confirman la obtención de unos niveles de depuración de los datos muy altos, confiables y de buena calidad; obteniendo así una nueva base de datos para posteriores estudios climáticos. [EN]A new database of monthly average rainfall and monthly average maximum and minimum temperatures has been developed, with which data from 142 weather stations obtained from the Agencia Estatal de Meteorología (AEMET) for the period (1989-2018) have been analysed. This study presents the results of different homogenisation and backfilling tests of 134, 172 and 176 temperature and precipitation series from stations located in the region of Extremadura. For this purpose, a first quality control of the data was carried out in compliance with the requirements of the World Meteorological Organisation (WMO) and the recommendations indicated by the Royal Netherlands Meteorological Institute (KNMI). Subsequently, the series were homogenised using Climatol software, in which different functions have been implemented to clean the data through an analysis of outliers and homogeneity, as well as filling in the gaps in the series. The analyses confirm the achievement of very high, reliable and good quality data cleaning levels, thus obtaining a new database for further climate studies. Esta investigación fue financiada por la Junta de Extremadura y el Fondo Europeo de Desarrollo Regional (FEDER) a través de la ayuda al grupo de investigación Alcántara (TIC008), GR21006, y el Proyecto IB18001 “Análisis y modelización del impacto del cambio climático sobre la distribución de zonas vitícolas en Extremadura”. Ponencia presentada en: XII Congreso de la Asociación Española de Climatología celebrado en Santiago de Compostela entre el 19 y el 21 de octubre de 2022.

Recycled waste materials obtained from industrial and agricultural processes are becoming promising thermal and acoustic insulating solutions in building applications; their use can play an important role in the environmental impact reduction. The aim of the present paper is the evaluation of the thermal performance of recycled waste panels consisting of cork scraps, rice husk, coffee chaff, and end-life granulated tires, glued in different weight ratios and pressed. Six panels obtained from the mixing of these waste materials were fabricated and analyzed. In particular, the scope is the selection of the best compromise solutions from the thermal and environmental points of view. To this aim, thermal resistances were measured in laboratory and a Life Cycle Assessment (LCA) analysis was carried out for each panel; a cross-comparative examination was performed in order to optimize their properties and find the best panels solutions to be assembled in the future. Life Cycle Analysis was carried out in terms of primary Embodied Energy and Greenhouse Gas Emissions, considering a ‘‘cradle-to-gate” approach. The obtained thermal conductivities varied in the 0.055 to 0.135 W/mK range, in the same order of magnitude of many traditional systems. The best thermal results were obtained for the panels made of granulated cork, rice husk, and coffee chaff in this order. The rubber granulate showed higher values of the thermal conductivity (about 0.15 W/mK); a very interesting combined solution was the panel composed of cork (60%), rice husk (20%), and coffee chaff (20%), with a thermal conductivity of 0.08 W/mK and a Global Warming Potential of only 2.6 kg CO2eq/m2. Considering the Embodied Energy (CED), the best solution is a panel composed of 56% of cork and 44% of coffee chaff (minimum CED and thermal conductivity).

Flare stacks are a key element in the safety of petrochemical and refinery industries; the correct operating conditions thereof must be ensured through a schedule for the periodic reviewing of all parts thereof. Advances in Non-Destructive Testing (NDT) in recent years and the application thereof to this field allow reliable, objective information to be obtained. This article describes and groups together the main applicable NDT techniques, analysing their advantages and disadvantages, updated with the new possibilities offered by unmanned aircraft or drones.