Metodología para la predicción de ampacidad en líneas eléctricas aéreas a partir de medidas directas y predicciones meteorológicas.

155 p.En los últimos años, la demanda de energía eléctrica ha aumentado de forma considerable, pero las redes eléctricas no están preparadas para integrar un mayor flujo de energía. Las líneas más cortas de una red, como las que conectan parques eólicos, o las líneas de distribución, están limitadas térmicamente. La ampacidad se define como la corriente máxima que puede conducir un conductor de manera continuada, cumpliendo los criterios de diseño y seguridad de la línea en la que se utiliza, y en conductores aéreos depende de las condiciones meteorológicas. Las compañías eléctricas calculan un límite térmico estático, asumiendo unas condiciones meteorológicas constantes durante todo el año, o durante toda una estación. Pero el límite estático desaprovecha parte de la capacidad térmica de las líneas y no está exento de riesgos. Una posible solución consiste en estimar la ampacidad de forma dinámica, conforme varían las condiciones ambientales. Estimar la ampacidad en tiempo real presenta ventajas en operación, pero los mercados eléctricos comercializan la energía con uno o varios días de antelación, por lo que es igualmente ventajosa su predicción.En la tesis se ha desarrollado una metodología que, combinando medidas directas en la línea ypredicciones meteorológicas, permite predecir la ampacidad de líneas aéreas. Los dispositivos de medición proporcionan medidas locales, pero las predicciones meteorológicas se obtienen a partir de modelos de la atmósfera a una escala mayor, lo que hace necesario su adaptación a la localización de la línea. La predicción puntual de la ampacidad no permite gestionar adecuadamente el nivel de riesgo derivado de una temperatura excesiva de los conductores, por lo que se hacen necesarias predicciones probabilísticas. Adicionalmente, se ha establecido una metodología para la evaluación de las predicciones, definiendo una serie de indicadores que permiten evaluar las predicciones tanto desde el punto de vista de la seguridad, como desde el punto de vista de aprovechamiento de la línea eléctrica. Aunque los conductores de la línea piloto para los que se ha validado la metodología son de tipo ACSR, esta también se ha validado para conductores HTLS, de alta temperatura y flecha reducida

Portugal SB13: contribution of sustainable building to meet EU 20-20-20 targets

Proceedings of the International Conference Portugal SB13: contribution of sustainable building to meet EU 20-20-20 targetsThe international conference Portugal SB13 is organized by the University of Minho, the Technical University of Lisbon and the Portuguese Chapter of the International Initiative for a Sustainable Built Environment in Guimarães, Portugal, from the 30th of October till the 1st of November 2013. This conference is included in the Sustainable Building Conference Series 2013-2014 (SB13-14) that are being organized all over the world. The event is supported by high prestige partners, such as the International Council for Research and Innovation in Building and Construction (CIB), the United Nations Environment Programme (UNEP), the International Federation of Consulting Engineers (FIDIC) and the International Initiative for a Sustainable Built Environment (iiSBE). Portugal SB13 is focused on the theme â Sustainable Building Contribution to Achieve the European Union 20-20-20 Targetsâ . These targets, known as the â EU 20-20-20â targets, set three key objectives for 2020: - A 20% reduction in EU greenhouse gas emissions from 1990 levels; - Raising the share of EU energy consumption produced from renewable resources to 20%; - A 20% improvement in the EU's energy efficiency. Building sector uses about 40% of global energy, 25% of global water, 40% of global resources and emit approximately 1/3 of the global greenhouse gas emissions (the largest contributor). Residential and commercial buildings consume approximately 60% of the worldâ s electricity. Existing buildings represent significant energy saving opportunities because their performance level is frequently far below the current efficiency potentials. Energy consumption in buildings can be reduced by 30 to 80% using proven and commercially available technologies. Investment in building energy efficiency is accompanied by significant direct and indirect savings, which help offset incremental costs, providing a short return on investment period. Therefore, buildings offer the greatest potential for achieving significant greenhouse gas emission reductions, at least cost, in developed and developing countries. On the other hand, there are many more issues related to the sustainability of the built environment than energy. The building sector is responsible for creating, modifying and improving the living environment of the humanity. Construction and buildings have considerable environmental impacts, consuming a significant proportion of limited resources of the planet including raw material, water, land and, of course, energy. The building sector is estimated to be worth 10% of global GDP (5.5 trillion EUR) and employs 111 million people. In developing countries, new sustainable construction opens enormous opportunities because of the population growth and the increasing prosperity, which stimulate the urbanization and the construction activities representing up to 40% of GDP. Therefore, building sustainably will result in healthier and more productive environments. The sustainability of the built environment, the construction industry and the related activities are a pressing issue facing all stakeholders in order to promote the Sustainable Development. The Portugal SB13 conference topics cover a wide range of up-to-date issues and the contributions received from the delegates reflect critical research and the best available practices in the Sustainable Building field. The issues presented include: - Nearly Zero Energy Buildings - Policies for Sustainable Construction - High Performance Sustainable Building Solutions - Design and Technologies for Energy Efficiency - Innovative Construction Systems - Building Sustainability Assessment Tools - Renovation and Retrofitting - Eco-Efficient Materials and Technologies - Urban Regeneration - Design for Life Cycle and Reuse - LCA of sustainable materials and technologies All the articles selected for presentation at the conference and published in these Proceedings, went through a refereed review process and were evaluated by, at least, two reviewers. The Organizers want to thank all the authors who have contributed with papers for publication in the proceedings and to all reviewers, whose efforts and hard work secured the high quality of all contributions to this conference. A special gratitude is also addressed to Eng. José Amarílio Barbosa and to Eng. Catarina Araújo that coordinated the Secretariat of the Conference. Finally, Portugal SB13 wants to address a special thank to CIB, UNEP, FIDIC and iiSBE for their support and wish great success for all the other SB13 events that are taking place all over the world

Advances on Smart Cities and Smart Buildings

Modern cities are facing the challenge of combining competitiveness at the global city scale and sustainable urban development to become smart cities. A smart city is a high-tech, intensive and advanced city that connects people, information, and city elements using new technologies in order to create a sustainable, greener city; competitive and innovative commerce; and an increased quality of life. This Special Issue collects the recent advancements in smart cities and covers different topics and aspects

Optimal Control of Hybrid Systems and Renewable Energies

This book is a collection of papers covering various aspects of the optimal control of power and energy production from renewable resources (wind, PV, biomass, hydrogen, etc.). In particular, attention is focused both on the optimal control of new technologies and on their integration in buildings, microgrids, and energy markets. The examples presented in this book are among the most promising technologies for satisfying an increasing share of thermal and electrical demands with renewable sources: from solar cooling plants to offshore wind generation; hybrid plants, combining traditional and renewable sources, are also considered, as well as traditional and innovative storage systems. Innovative solutions for transportation systems are also explored for both railway infrastructures and advanced light rail vehicles. The optimization and control of new solutions for the power network are addressed in detail: specifically, special attention is paid to microgrids as new paradigms for distribution networks, but also in other applications (e.g., shipboards). Finally, optimization and simulation models within SCADA and energy management systems are considered. This book is intended for engineers, researchers, and practitioners that work in the field of energy, smart grid, renewable resources, and their optimization and control

Design and optimization under uncertainty of Energy Systems

In many engineering design and optimisation problems, the presence of uncertainty in data and parameters is a central and critical issue. The analysis and design of advanced complex energy systems is generally performed starting from a single operating condition and assuming a series of design and operating parameters as fixed values. However, many of the variables on which the design is based are subject to uncertainty because they are not determinable with an adequate precision and they can affect both performance and cost. Uncertainties stem naturally from our limitations in measurements, predictions and manufacturing, and we can say that any system used in engineering is subject to some degree of uncertainty. Different fields of engineering use different ways to describe this uncertainty and adopt a variety of techniques to approach the problem. The past decade has seen a significant growth of research and development in uncertainty quantification methods to analyse the propagation of uncertain inputs through the systems. One of the main challenges in this field are identifying sources of uncertainty that potentially affect the outcomes and the efficiency in propagating these uncertainties from the sources to the quantities of interest, especially when there are many sources of uncertainties. Hence, the level of rigor in uncertainty analysis depends on the quality of uncertainty quantification method. The main obstacle of this analysis is often the computational effort, because the representative model is typically highly non-linear and complex. Therefore, it is necessary to have a robust tool that can perform the uncertainty propagation through a non-intrusive approach with as few evaluations as possible. The primary goal of this work is to show a robust method for uncertainty quantification applied to energy systems. The first step in this direction was made doing a work on the analysis of uncertainties on a recuperator for micro gas turbines, making use of the Monte Carlo and Response Sensitivity Analysis methodologies to perform this study. However, when considering more complex energy systems, one of the main weaknesses of uncertainty quantification methods arises: the extremely high computational effort needed. For this reason, the application of a so-called metamodel was found necessary and useful. This approach was applied to perform a complete analysis under uncertainty of a solid oxide fuel cell hybrid system, starting from the evaluation of the impact of several uncertainties on the system up to a robust design including a multi-objective optimization. The response surfaces have allowed the authors to consider the uncertainties in the system when performing an acceptable number of simulations. These response were then used to perform a Monte Carlo simulation to evaluate the impact of the uncertainties on the monitored outputs, giving an insight on the spread of the resulting probability density functions and so on the outputs which should be considered more carefully during the design phase. Finally, the analysis of a complex combined cycle with a flue gas condesing heat pump subject to market uncertainties was performed. To consider the uncertainties in the electrical price, which would impact directly the revenues of the system, a statistical study on the behaviour of such price along the years was performed. From the data obtained it was possible to create a probability density function for each hour of the day which would represent its behaviour, and then those distributions were used to analyze the variability of the system in terms of revenues and emissions