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El desplegament dels sistemes de generació renovable en xarxes elèctriques, com els parcs eòlics i fotovoltaics, és un repte tecnològic degut a la variabilitat del recurs renovable: el vent i el sol. Una de les possibles eines existents actualment per fer la potència generada per aquests parcs totalment controlable, afavorint així la seva integració en xarxa, és incloure un sistema d`emmagatzematge d`energia en els parcs (per exemple, un banc de bateries). No obstant, aquesta opció encara és incipient i subjecte a nombroses preguntes: i) És una solució econòmicament rendible?; ii) Quins serveis dintre del parc aquest sistema d`emmagatzematge podria proveir i com es valorarien en els mercats elèctrics?; iii) Quines barreres de tipus tecnològic s`han de superar per fer aquesta opció practicable? Atenent les preguntes abans formulades, el primer objectiu d`aquest projecte és definir les potencials aplicacions dels sistemes d`emmagatzematge d`energia en parcs de generació renovable. També, i com a segon objectiu, es vol quantificar l`impacte tècnic i econòmic de la inclusió d`aquests sistemes d`emmagatzematge en els parcs. La metodologia inclou revisió de literatura, modelització i simulació amb ordinador, així com optimització matemàtica.

El constante aumento del precio de la factura de la luz y el descenso de los precios de los módulos fotovoltaicos hace que el autoconsumo eléctrico a partir de placas solares sea cada vez más factible y atractivo para el consumidor. A pesar de esto, también hay que tener en cuenta varios aspectos que pueden resultar problemáticos a la hora de instalar un sistema fotovoltaico, como el coste de la inversión inicial, la necesidad de almacenar la energía que no se consume o la zona geográfica en la que se encuentre la instalación. Para conseguir hacer un análisis de la viabilidad económica lo más real posible es importante contar con datos de consumo de potencia a tiempo real, y es por ello que uno de los pilares del proyecto es el desarrollo de un dispositivo que nos permita consultar el consumo eléctrico de un hogar con muestras cada segundo. El constant augment del preu de la factura de la llum i la baixada dels preus dels mòduls fotovoltaics fa que l'autoconsum elèctric a partir de plaques solars sigui cada vegada més factible i atractiu per al consumidor. Malgrat això, també s'ha de tenir en compte alguns aspectes que poden resultar problemàtics a l'hora d'instal·lar un sistema fotovoltaic, com el cost de la inversió inicial, la necessitat d'emmagatzemar l'energia que no es consumeix i la zona geogràfica en la qual es trobi la instal·lació. Per aconseguir fer un anàlisi de la viabilitat econòmica lo més real possible és important comptar amb dades de consum de potència a temps real, i es per això que un dels pilars del projecte és el desenvolupament d'un dispositiu que ens permeti consultar el consum elèctric d'una llar amb mostres cada segon. The constant increase in the price of the electricity bill and the decrease in the prices of photovoltaic modules makes self-consumption of electricity from solar panels increasingly feasible and attractive to the consumer. Despite this, it is also necessary to take into account several aspects that can be problematic when installing a photovoltaic system, such as the cost of the initial investment, the need to store the energy that is not consumed or the geographical area in which the installation is located. In order to make an analysis of economic viability as real as possible, it is important to have real-time power consumption data, and that is why one of the pillars of the project is the development of a device that allows us to track the electricity consumption of a home with samples every second.

This paper provides an overview of the last 40 years of use, and in many cases abuse, of the natural resources in Catalonia, a country that is representative of European countries in general, and especially those in the Mediterranean region. It analyses the use of natural resources made by mining, agriculture, livestock, logging, fishing, nature tourism, and energy production and consumption. This use results in an ecological footprint, i.e., the productive land and sea surface required to generate the consumed resources and absorb the resulting waste, which is about seven times the amount available, a very high number but very similar to other European countries. This overexploitation of natural resources has a huge impact on land and its different forms of cover, air, and water. For the last 25 years, forests and urban areas have each gained almost 3% more of the territory at the expense of agricultural land; those municipalities bordering the sea have increased their number of inhabitants and activity, and although they only occupy 6.7% of the total surface area, they account for 43.3% of the population; air quality has stabilized since the turn of the century, and there has been some improvement in the state of aquatic ecosystems, but still only 36% are in good condition, while the remainder have suffered morphological changes and different forms of nonpoint source pollution; meanwhile the biodiversity of flora and fauna remains still under threat. Environmental policies do not go far enough so there is a need for revision of the legislation related to environmental impact and the protection of natural areas, flora, and fauna. The promotion of environmental research must be accompanied by environmental education to foster a society which is more knowledgeable, has more control and influence over the decisions that deeply affect it. Indeed, nature conservation goes hand in hand with other social and economic challenges that require a more sustainable vision. Today’s problems with nature derive from the current economic model, which is environmentally unsustainable in that it does not take into account environmental impacts. Lastly, we propose a series of reasonable and feasible priority measures and actions related to each use made of the country’s natural resources, to the impacts they have had, and to their management, in the hope that these can contribute to improving the conservation and management of the environment and biodiversity and move towards sustainability.

Sensorless control of Electric Vehicle (EV) drives is considered to be an effective approach to improve system reliability and to reduce component costs. In this paper, relevant aspects relating to the sensorless operation of EVs are reported. As an initial contribution, a hybrid sensorless control algorithm is presented that is suitable for a variety of synchronous machines. The proposed method is simple to implement and its relatively low computational cost is a desirable feature for automotive microprocessors with limited computational capabilities. An experimental validation of the proposal is performed on a full-scale automotive grade platform housing a 51¿kW Permanent Magnet assisted Synchronous Reluctance Machine (PM-assisted SynRM). Due to the operational requirements of EVs, both the strategy presented in this paper and other hybrid sensorless control strategies rely on High Frequency Injection (HFI) techniques, to determine the rotor position at standstill and at low speeds. The introduction of additional high frequency perturbations increases the power losses, thereby reducing the overall efficiency of the drive. Hence, a second contribution of this work is a simulation platform for the characterization of power losses in both synchronous machines and a Voltage Source Inverters (VSI). Finally, as a third contribution and considering the central concerns of efficiency and autonomy in EV applications, the impact of power losses are analyzed. The operational requirements of High Frequency Injection (HFI) are experimentally obtained and, using state-of-the-art digital simulation, a detailed loss analysis is performed during real automotive driving cycles. Based on the results, practical considerations are presented in the conclusions relating to EV sensorless control. Peer Reviewed

The wide-ranging literature on food systems provides multiple perspectives and world views. Various stakeholders define food and food systems in non-equivalent ways. The perception of the performance of food systems is determined by these specific perspectives, and a wide variety of policies responding to different aims are proposed and implemented accordingly. This paper sets out to demonstrate that the pre-analytical adoption of different narratives about the food system leads to non-equivalent assessments of the performance of food supply chains. In order to do so, we (i) identify a set of relevant narratives on food supply chains in Spanish and Catalan contexts; (ii) identify the pertinent attributes needed to describe and represent food supply chains within the different perspectives or narratives; and (iii) carry out an integrated assessment of three organic tomato supply chains from the different perspectives. In doing so, the paper proposes an analysis of narratives to enable the analyst to characterize the performance of food supply chains from different perspectives and to identify the expected trade-offs of integrated assessment, associating them with the legitimate-but-contrasting views found among the social actors involved.

El presente proyecto de final de máster consiste en el análisis de un edificio ya existente que se encuentra protegido con un nivel B ubicado en la C/ Elkano, 11 de Barcelona, con el propósito de redactar un proyecto de rehabilitación energética de dicho edificio basado en las mejores soluciones posibles. El objetivo principal pretende analizar el edificio escogido y llevar a cabo una serie de propuestas para su rehabilitación, con la finalidad de mejorarlo en criterios de sostenibilidad, además de reducir la demanda y el consumo energético global del edificio en cuestión. Utilizaremos como punto de partida los resultados obtenidos del Certificado de Eficiencia Energética del edificio, generado a partir del programa CE3X. En este proyecto se estudiará la incorporación de mejoras energéticas, tanto en los sistemas activos, instalaciones del edificio, como en los sistemas pasivos y se especificarán los materiales a utilizar. La selección de cada sistema y material se realizará mediante una comparativa de las distintas soluciones posibles, valorando su impacto medioambiental, la vida útil del material, su origen y el consumo energético durante la vida de los materiales. Para finalizar el análisis se incorpora una valoración económica estimada de las actuaciones seleccionadas, a través de la cual podremos establecer la viabilidad y los periodos de amortización de la intervención. Mediante la elaboración de este proyecto se desea establecer mejoras en el sistema constructivo de los edificios históricos construidos en Barcelona a finales del siglo XIX y principios del siglo XX, aportando soluciones innovadoras como el aislamiento térmico, la incorporación de energías renovables o las cubiertas verdes.