NOT CONVENTIONAL ENERGY SOURCES

Author: RUIZ CELMA ANTONIO.
Year: 2002.
University: EXTREMADURA [www.unex.es].
Place of defense: ESCUELA DE INGENIERIAS INDUSTRIALES.
Place of preparation: ESCUELA DE ING.INDUSTRIALES DE BADAJOZ.

Summary: The aim of the thesis is the definition of a proposed power plant antónoma of alpernejos within the geographic scope of Extremadura. The work begins with the analysis of the main properties of interest in biomass technologies and energy conversion desponibles at present to carry out the exploitation of these recursos.Como starting point for any project of these things is necessary knowledge, environment and so develops carectización of major resources biovasicos of origenn agriculture and agribusiness in Extremadura. The second part of the work is carried configuration of the power plant with online refresher mechanical, thermal drying line, without plen steam cycle and concentration of alfechan first through employment as a coolant to condensadro and later through the use of thermal energy from gas chooses.

Author: DE LA CASA HERNANDEZ JESUS.
Year: 2003.
University: JAÉN [www.ujaen.es].
Place of defense: ESCUELA POLITECNICA SUPERIOR DE JAEN.
Place of preparation: ESCUELA POLITECNICA SUPERIOR DE JAEN.

Summary: Ensuring the security of people in the future photovoltaic installations is key requirement for the development of this sector, especially taking into account the progressive increase in risk in those electrical installations by the growth of their powers, and their locations increasingly coming the domestic sphere. The measures to protect people in conventional electrical systems are detailed rules and regulations binding (both domestic and international) to ensure the safety of themselves, regardless of the designer, installer and inspector involved in the installation. Thus, for more than a century of experience in these facilities, these rules and regulations have evolved in the light of technological advances and experience cumulada and have enabled an effective way of solving the problems related to security. The photovoltaic systems, in his recent appearance was in the early stages of this process, which is being initiated the development of legislation and the study of implementing effective protection measures. For this development, and as a prelude, it is necessary to study in depth the performance photovoltaic electric generator and its response in situations of default. Within this field of protection to persons have developed the work of this thesis, mainly in the study of the insulation of the generator and the operation and viability of various protective measures. The work has been divided into different phases: the first phase in which proposes various protective measures that can be used, the second describing the behavior of the generator with respect to land and proposes an equivalent circuit model, where the third he studies the isolation and leakage currents grounding of the generator, and finally, based on the results of the study examines the feasibility of the proposed protection measures.

Author: BERISTAIN JIMENEZ JOSE ANTONIO.
Year: 2004.
University: POLITÉCNICA DE CATALUÑA [www.upc.edu].
Place of defense: AULA 28.8 DE L'ETESIB. CAMPUS SUD.
Place of preparation: C4 Despatx Direcció nord.

Summary: In this thesis is the analysis and synthesis of investors with bidirectional isolation in high frequency. Among the applications that can be covered include: photovoltaic power systems, power systems using fuel cells, mini-generadores wind and compensation harmonica. There are two major requirements for a number of these applications. First, it is necessary to provide electrical isolation between the source of direct current and alternating current burden, mainly by security issues, and secondly some applications require energy storage on the side DC. Some of these applications are used batteries as a means of storing energy. The transformer that provides electrical isolation, it must be small in size and low cost. The trend in investors insulated power is to introduce a processor running at high frequency, so that the high frequency of operation falls in a high power density, maintaining limited losses in the core. Batteries or equivalent source delivered a voltage DC, through the investor becomes voltage alternating current that feeds loads of different types. If there reactive power due to a highly inductive or capacitive load, it is interesting that this power is returned to the power source, in our case the batteries, so that eliminates the need for a high-capacity capacitor between the bus dc battery and the burden of ca. Also, the batteries can be loaded from the side of alternating current through a generator or across the line of alternating current. This is, by a single converter, the ability to deliver power from batteries or receive. There must be a high-quality waveform of the tension that comes either isolated systems or the AC line. To help improve the quality of the output voltage of the inverter, are explored in the type of multilevel topologies that have a low harmonic distortion of the output voltage, and also allow the drastic reduction in the size of the output filter, and through appropriate management of the tensions, the increasing impact on total return to investors. The methodology of work that remains during the conduct of this dissertation is summarized in the following points: -- A proposal for a methodology for the analysis and synthesis of investors with bidirectional isolation in high frequency. -- Implementation of the proposed methodology to investors with bidirectional isolation in high-frequency two levels, which are used as a starting point and then extend the methodology to investors bidirectional multilevel. -- Proposal for a new investor bidirectional multi-insulated high frequency topologies based on the full bridge / middle bridge. Implementation of the methodology for the analysis of multilevel investor. -- Proposal for a new investor with multilevel bidirectional isolation in high-frequency-based topologies push-pull/puente complete. Implementation of the proposed methodology for the analysis of multilevel investor. -- Presentation of results from simulation of the strategies of modulation used for two-tier investors and multi-loop and open-loop closed. Presentation of the design criteria for the conduct of investors. Presenting the results of experimental investors with bidirectional isolation in high frequency. The experimental results include: waveforms working in open-loop and closed-loop data of the total harmonic distortion of tension before the output filter pasabajos, performance data and evaluation of the results obtained.

Author: RAMÍREZ GONZÁLEZ PENÉLOPE.
Year: 2005.
University: LAS PALMAS DE GRAN CANARIA [www.ulpgc.es].
Place of defense: E.T.S.DE INGENIEROS INDUSTRIALES.
Place of preparation: ESCUELA TÉCNICA SUPERIOR DE INGENIEROS INDUSTRIALES.

Summary: DOCTORAL THESIS: STATISTICAL MODELING OF THE CHARACTERISTICS OF WIND ENERGY FOR EVALUATION. APPLICATION TO THE CANARY ISLANDS. PhD student: DÂ meetings. Penelope Gonzalez Ramirez Director: Dr. D. Jose Antonio Gonzalez Charter Las Palmas de Gran Canaria, March 2006 Due to the uncertain nature of the wind, it is necessary to provide more accurate models for the study of the wind resource and its utilization in contributing to the coverage of the electricity demand in regions such as the Canary Islands, where coincide circumstances such as high wind potential, space limitations and restrictions on the injection of the electricity generated in the electricity grids island. This is primarily a collection of wind data recorded in the Canary Islands for further analysis, they selected according to criteria of reliability and record length. It then continues with the analysis of the laws of distribution standard used in the past to describe the wind regimes, as well as continuous distribution laws unused so far in the description of wind regimes, which also includes parameters not covered previous studies in order to determine the efficiency of the same in the goodness of fit to the experimental data. These parameters are estimated using a variety of methods: Moments, Minimum and Maximum Verosimilitud Squares. This raises the Principle of Maximum Entropy (PME) restricted by statistical moments, in the search for non-standard statistical models. The models described are applied to determine the effectiveness of the same in describing schemes wind of the Canary archipelago. The efficiency of the various laws analyzed distribution is deducted from the goodness of fit and the ability of the model to describe the experimental wind energy. Discusses also influence the degree of alignment of distributions considered in estimating the average power produced by a wind turbine, depending on the size. In compiling inputs and final conclusions, he stressed, above all, that all laws analyzed and applied to the stations in the study, those from SMEs with limited time and distribution mixture of two components Weibull-2 provides the best settings the wind data of the Canary archipelago. Also, there are other laws, such as the Generalized Gamma three parameters and the distribution Beta three parameters that provide a better match that the Weibull distribution of two parameters, normally recommended in the scientific literature. On the other hand, in developing this thesis, stresses the proposal for a method for estimating the independence of a sample of hourly wind speeds.

Author: DELGADO MARTIN AGUSTIN.
Year: 2005.
University: NACIONAL DE EDUCACIÓN A DISTANCIA [www.uned.es].
Place of defense: E.T.S. INGENIEROS INDUSTRIALES.
Place of preparation: UNIVERSIDAD NACIONAL DE EDUCACIÓN A DISTANCIA.

Summary: In the work of this thesis describes recent advances in the field of scenario penetration of the Solar Energy Photovoltaics (ESF) in the electrical, within the department of Electrical Engineering, Electronic and Control Technical School Senior Industrial Engineers at UNED. The current energy model based on fossil fuels is not sustainable. In the search for alternatives, the ESF is an option that has numerous advantages, among which the resource potential of solar far superior to the energy demand. There are numerous reports, some with great tradition, seeking to explore which could be potential energy scenarios in the future. In chapter 2 of the thesis provides a comprehensive review of all of them, from the most general, to the most specific ESF and justified the realization of this thesis, as a necessary effort to integrate the same methodology in all aspects Relevant a possible large-scale introduction of the ESF. The methodology developed is based on the use of indicators that describe the scenarios and variables that modify through models that simulate their behavior. These models are described in the central part of the memory and relate to topics such as generating capacity, competitiveness dela ESF, the coupling of energy generated with the current demand profiles or environmental effects To facilitate the realization of the scenarios , has developed a software application that allows the processing of all data generated and analysis of the results obtained. Finally, it applies the methodology developed the construction of three types of different scenarios. The assumptions are based on a comprehensive review of existing literature and the results show promising figures. The ESF is likely to provide a significant portion of the electricity and displays a high degree of coupling with demand, thereby avoiding some of the need to store the energy generated. All this within a price reduction makes the ESF can compete in the medium term with the challenge of generation technologies, but with a much smaller environmental impact.

Author: ELVIRA MORALES RAFAEL.
Year: 2005.
University: LA RIOJA [www.unirioja.es].
Place of defense: ESCUELA TÉCNICA SUPERIOR DE INGENIERÍA INDUSTRIAL.
Place of preparation: ESCUELA SUPERIOR DE INGENIERÍA INDUSTRIAL.

Summary: From the perspective of climate change, to address the problem of the growing presence of CO2 in the atmosphere under a dual perspective: The work of forests Riojan (and the most representative tree species) as fixing atmospheric carbon and employment forest biomass in sustitición fuel organic or mineral origin, as a buffer CO2 emissions, calculating reserves for this potential energy TEP One of the most abundant tree species in the Community: "The quejigo" (Quercus pyrenaica). The link between changing atmospheric conditions which are scheduled occurs on the planet and study to be presented in the thesis developed, is given by the Spanish Forest Plan in terms of the two main steps that the Plan proposed for the fight against such a change: the work of forests as carbon sinks and highly polluting fuel substitution by other vegetable. The work is presented, once identified theories on climate change, its potential impact, raised the relationship between power sources mineral or organic, and the increase in ambient temperatures and the need for the replacement of these sources for renewable energy, deals specifically with the work of fixing atmospheric carbon in forests of La Rioja, both at present and in future inventory stocking (including variation experienced over time), and use of forest biomass as possible substitute fuel source mineral or organic, all measures envisaged in the plans developed for the mitigation of emissions of greenhouse gases. It emphasizes the study, with emphasis on the kind Quescus pyrenaica, known as La Rioja "rebollo" in response to its wide distribution in the territory of the Community and its potential use as fuel. Objectives: First. Quantification of carbon retained by the forest in La Rioja and its evolution over time. Second. Study the impact that the implementation of Spanish Forest Plan (EDP) will be in La Rioja, in the effect sink their forests. Third. Calculation of energy reserves (including its evolution over time) of the species Quercus pyrenaica (rebollo) as a prelude to its possible use as a renewable energy source. Fourth. Evaluation of CO2 emissions avoided by the use of forest biomass as a replacement for other fuels mineral or organic origin. Regarding La Rioja can be extracted from those contained in the preceding paragraphs interesting consequences among which the parovechamiento of leñas in rebollo is far below its real possibility.

Author: López Talavera Diego.
Year: 2006.
University: JAÉN [www.ujaen.es].
Place of defense: Escuela Politécnica Superior.
Place of preparation: Escuela Politécnica Superior.

Summary: In this Doctoral Thesis revising classic analysis of economic profitability of investment projects, and particularized rewritten for photovoltaic systems connected to the network. Based on the mathematical expressions obtained, a tool to obtain a fast and simple way the internal rate of return, in tabular form, accompanied by a procedure for uso- thereby avoiding the realization of calculations cumbersome. Lastly is a study from an economic point of view about the effectiveness of the major financial incentives to support photovoltaic systems connected to the network existing in different countries, through the internal rate of return, using its estimate for the tool created.

Author: Táboas Touceda Francisco.
Year: 2006.
University: ROVIRA I VIRGILI [www.urv.cat].
Place of defense: Escuela Técnica Superior de Ingeniería Química.
Place of preparation: Escuela Técnica Superior de Ingeniería Química.

Summary: In recent years it has emerged a demand for cooling equipment by absorbing small power with a low temperature thermal actuation, primarily by the potential of harnessing solar thermal. The teams absorbing ammonia / water are postulated as an alternative to systems typical air conditioning with solar energy (whether adsorption or absorption with water lithium bromide), because they are appropriate for a team of small power for its great potential for reducing its size. Besides these systems can operate without cooling towers, which is suited to a small power equipment. The center of technological innovation CREVER, with the collaboration of the University of Vigo, proposed a research project entitled "Development of advanced components for the design and manufacture of refrigeration machinery absorption of NH3-H2O small power and thermal activation at low temperature. " This project is focused on developing models for calculating the three teams that were identified as critical in their design: absorber, generator and rectifier. In the development of this project were identified interchanges plate as the appropriate solution to minimize the size of the absorber and generator, reducing the burden on equipment, and maximize the temperatures of energy sources. That argument has been made within the framework of this project and has as its main objective the pilot study of the process of boiling forced mixing ammonia / water in a channel of a exchanger plates. The experiment was conducted in the conditions of operation of a generator by a team of absorption of ammonia / water has been studied and the effect on heat transfer coefficients of mass flow in the exchanger, heat flux, pressure and concentration the mixture. The conditions of the experiments have ranged from 0.33 to 0.65 in mass fraction of ammonia, and the generation of maximum vapor by 30%. The range of pressures is from 7 to 15 bar, heat fluxes between 20 kW/m2 to 70 kW/m2 and flows másicos from 50 to 170 kg/m2s. Experimental data obtained show a predominance of boiling convecting against the nucleation phenomena. The magnification factor of boiling convecting is less than that obtained in tubes, reflecting the effect of corrugación is most important single phase flow boiling. We have appreciated apparent nucleation phenomena in experiments, but in this area the coefficient of heat transfer depends on the mass flow. The influence of pressure and the concentration of the mixture into the boiling coefficients in the range studied, are negligible compared to the effects of mass flow and heat flux. Experimental data obtained in the exchanger plates have been compared with the correlations proposed in the literature for application to plate heat exchangers. Based on the findings from this analysis has been proposed for calculating the correlation coefficient boiling forced mixing ammonia / water in the exchanger plates tested. This correlation predicts 95% of the experimental data with a 20% error.

Author: Pérez Bayer Juan Fernando.
Year: 2007.
University: VALLADOLID [www.uva.es].
Place of defense: E.T.S. de Ingenieros Industriales.
Place of preparation: Universidad de VAlladolid - Escuela Técnica Superior de Ingenieros Industriales..

Summary: In this Doctoral Thesis develops a mathematical model of the process of biomass gasification in a reactor equicorriente based on balance térmo-químico. The model predicts the end of the lean gas composition and temperature of reaction, and it is a parametric study which investigates how they influence the process, the moisture content of biomass and dosado on gasification; predicting parameters such as performance the first law of thermodynamics, the calorific value of lean gas, the quantity of water decoupled, etc., obtaining a support tool for the study of the behavior of different types of biomass under the gasification process, and for the design and optimization plants. It also presents a model one-dimensional stationary process biomass gasification in fixed bed equicorriente, which coupled with the conservative equations drying, pyrolysis (composition of volatile depending on the type of biomass), and oxidation of coal volatile reduction H2, CO2, and (H2O) v with coal, reforming reactions of hydrocarbons, energy exchanges, heat transfer by radiation in the solid phase (energy flow), variation in the free fraction of particle diameter and between others. The model looks, how they affect the main process variables in the forward speed of the front flame and thus their effect on efficiency. A parametric study, varying the size of the particles, the superficial velocity of the air, the moisture content of biomass and the diameter of the gasifier, it investigates their effect; whose performance of the process is at a lower maximum particle size, less speed Superficial, lower moisture content and greater diameter gasifier, because it increases the fuel / air, and with it the calorific value of gas. The points of simulated operation, were validated experimentally (fields of temperature, rate of consumption of biomass gasification and dosado on, among others), which emphasizes the good agreement between the data calculated by the model and the experimental.