abstract: Concentrating Solar Power (CSP) plant technology can produce reliable and dispatchable electric power from an intermittent solar resource. Recent advances in thermochemical energy storage (TCES) can offer further improvements to increase off-sun operating hours, improve system efficiency, and the reduce cost of delivered electricity. This work describes a 111.7 MWe CSP plant with TCES using a mixed ionic-electronic conducting metal oxide, CAM28, as both the heat transfer and thermal energy storage media. Turbine inlet temperatures reach 1200 °C in the combined cycle power block. A techno-economic model of the CSP system is developed to evaluate design considerations to meet targets for low-cost and renewable power with 6-14 hours of dispatchable storage for off-sun power generation. Hourly solar insolation data is used for Barstow, California, USA. Baseline design parameters include a 6-hour storage capacity and a 1.8 solar multiple. Sensitivity analyses are performed to evaluate the effect of engineering parameters on total installed cost, generation capacity, and levelized cost of electricity (LCOE). Calculated results indicate a full-scale 111.7 MWe system at $274 million in installed cost can generate 507 GWh per year at a levelized cost of $0.071 per kWh. Expected improvements to design, performance, and costs illustrate options to reduce energy costs to less than $0.06 per kWh. / Dissertation/Thesis / Masters Thesis Civil, Environmental and Sustainable Engineering 2017

Le stockage de l'énergie et la valorisation du CO2 sont des enjeux d'avenir. A ce jour, l'électricité est une ressource non stockable massivement. Un stockage sous forme chimique peut être une réponse à ce défi et être d'autant plus intéressant si le procédé consomme du CO2. La conversion du CO2 dans un électrolyseur à conduction protonique PCEC (Proton Ceramic Electrolysis Cell) fonctionnant à moyenne température (entre 400 et 600°C) en composés organiques valorisables, tels que le méthane ou le méthanol, permettrait de réaliser un stockage de l'énergie électrique sous forme d'énergie chimique. Cette conversion est appelée électrohydrogenation du CO2. L'électrolyseur, utilisé comme un outil de conversion, génère des protons qui, par réaction à la cathode avec le CO2, forment d'autres composés.Dans ce procédé, les paramètres expérimentaux tels que la température, la pression, les débits de gaz et la puissance (U et I) appliquées à l'assemblage électrodes/électrolyte influencent considérablement la nature des produits formés et leurs proportions. Plus particulièrement, de faibles débits de CO2 favorisent la formation de composés à bas point d'ébullition de type alcools, qui restent cependant très minoritaires par rapport à la formation de CO.Une réaction de co-électrolyse a pu être identifiée en raison de la présence de lacunes d'oxygène dans la structure perovkite constituant l'électrolyte. / The electrical energy storage is one of the main challenges of the century. The conversion of electrical energy into chemical energy is one of the several possibilities to store electrical energy. As CO2 is the most important gas responsible of greenhouse effect, the compilation of electrical energy storage and CO2 utilization in a process could be of particular interest. In the so-called electrohydrogenation process of CO2, a PCEC (Proton conductor electrolysis Cells) functioning at medium temperature (400°C and 600°C) is used to convert CO2 into organic compounds, like CH4 or CH3OH, to assess electrical energy transformation into chemical energy. The electrolyzer is a conversion tool which creates hydrogen protons that will react with CO2 at the cathode of the electrolyte/electrodes assembly.In this process, experimental parameters like the temperature, the pressure, the CO2 flow, and the power (U and I) applied at the assembly influence the nature and ratio of the different chemical products formed. Mainly, a low CO2 flow will promote the synthesis of products with a low melting point (alcools) even if these compounds are minor relative to CO formation.A co-electrolysis side reaction, caused by the oxygen vacancies in the perovkite (electrolyte), has been identified.

The renewable energy sources increase the volatility on theelectricity market. To manage the quick variations battery energystorage systems (BESS), together with other storing solutions, willbe required in the future. Depending on which level in the grid thebattery is placed, it can serve different purposes. In this report amarket analysis is conducted, which examine the performance ofbattery storages installed in Sweden. Further on, a simulation, withPV-panels and a battery, was performed at Behrn Arena in Örebro. From the market analysis it was shown that the majority of therespondents had used, or will use, their battery for peak shaving.This function is particularly meaningful for customers with a powertariff, which is the case for Behrn Arena. The simulated systemdecreased their yearly cost due to the power tariff with 70 000 SEKand the total electricity bill decreased with 155 000 SEK. For the batteries to be more profitable in the future, the batteryprice needs to decrease or the number of revenue streams need toincrease. One revenue with great potential is frequency regulation,which has proven its efficiency in other countries.

This work presents an energy system design for wireless sensor networks (WSNs) after applying our design the WSN should theoretically have an infinite lifetime. Energy harvesting sources can provide suitable energy for WSN nodes and reduce their dependence on battery. In this project, an efficient energy harvesting and storage system is proposed. By using (two supercapacitors and four DC/DC converters with step up /step down capabilities) all of them controlled by Microcontroller via switches to consider the best way to save energy to keep the WSN alive as long as possible. The usage of supercapacitors as an energy buffer to supply the sensor components (microcontroller and radio) with energy it needs to work. We could control the energy flow according to a specific voltage levels in supercapacitors to guaranty the full functionality for WSN with minimizing the loss of energy, and that’s leads to long time life for the wireless sensor node WSN. Another important thing we find in our experiment that is the inner leakage of the supercapacitor and how it has a critical effect on how long it can serve our system with energy. This paper contains on two theoretical sections (Part one and part two) which are based on literature reviews, and one experimental section (Part three) based on experimental building the prototype, coding and testing.

abstract: Battery energy storage has shown a lot of potential in the recent past to be effective in various grid services due to its near instantaneous ramp rates and modularity. This thesis aims to determine the commercial viability of customer premises and substation sited battery energy storage systems. Five different types of services have been analyzed considering current market pricing of Lithium-ion batteries and power conditioning equipment. Energy Storage Valuation Tool 3.0 (Beta) has been used to exclusively determine the value of energy storage in the services analyzed. The results indicate that on the residential level, Lithium-ion battery energy storage may not be a cost beneficial option for retail tariff management or demand charge management as only 20-30% of the initial investment is recovered at the end of 15 year plant life. SRP's two retail Time-of-Use price plans E-21 and E-26 were analyzed in respect of their ability to increase returns from storage compared to those with flat pricing. It was observed that without a coupled PV component, E-21 was more suitable for customer premises energy storage, however, its revenue stream reduces with addition to PV. On the grid scale, however, with carefully chosen service hierarchy such as distribution investment deferral, spinning or balancing reserve support, the initial investment can be recovered to an extent of about 50-70%. The study done here is specific to Salt River Project inputs and data. Results for all the services analyzed are highly location specific and are only indicative of the overall viability and returns from them. / Dissertation/Thesis / M.S. Electrical Engineering 2013

Dans le stockage d’énergie, les alternatives aux énergies fossiles sont peu nombreuses. Le stockage d’énergie dans un condensateur, permet d’atteindre de grande puissances électriques, mais pour une densité d’énergie trop faible. La présente thèse à pour objectif la compréhension des nano-céramiques ferroélectriques afin d’augmenter leur densité d’énergie et de se diriger ainsi vers un super-condensateur céramique. Nous avons développé dans un premier temps un modèle par champs effectif moyen du système core-shell. Une fois introduit dans l’énergie libre de Landau, ce modèle donne une idée de la densité d’énergie d’un système ferroélectrique donné. Les calculs – sur quelques pérovskites courantes - indiquent que la densité d’énergie reste relativement faible. Néanmoins nos calculs montrent que l’on peu optimiser le stockage d’énergie dans de telles céramiques en enrobant des grains de forme allongée comme des disques ou des fils. En outre, ce modèle phénoménologique permet d’expliquer de nombreuses mesures expérimentales sur les céramiques, y compris dans le cas ou s’ajoute de la conductivité et de la relaxation de Maxwell-Wagner. Nous nous sommes tournés par la suite vers une modélisation ab-initio : l’Hamiltonien effectif. La modélisation de nano-système core-shell de BaTiO3 a montré la présence d’un paramètre d’ordre particulier : le moment toroïdale. Ce paramètre d’ordre peut impliquer un comportement diélectrique différent. Introduit dans une description phénoménologique de type Landau, ce dernier est responsable de la disparition de la phase orthorhombique dans BaTiO3. La synthèse de nanoparticules de BaTiO3 de formes cubiques et homogènes, nous a permis de faire une série de mesure. Les mesures MET, RAMAN, RX, diélectriques sur les poudres et les céramiques, suggèrent la présences de transitions de phases générées par la présence d’un paramètre d’ordre similaire à celui observé dans modélisation ab-initio. / For energy storage applications, fossils energies are difficult to compete. By storing energy in capacitors, one can get a huge electric power. However the density of energy in a capacitor is too weak to be interesting in energy storage application. The present thesis aims to understand the well known core-shell system in ferroelectric nano-ceramics and the influence of the geometry of the grain in order to determine and optimize the density of energy in this kind of dielectric, going toward an ultra-capacitor of ceramics. We have first developed an effective-medium core-shell model. By introducing this model in the phenomenological Landau Free energy of several ferroelectrics, we can get quantitative information about of density of energy in these materials. Our calculation for common ferroelectrics has shown that the density of energy remains too weak to become interesting. However, the density of energy can be optimized by using nano-disks or nano-rods in a structured ceramic. Our model agrees well with experimental results, even with extrinsic phenomena like the Maxwell-Wagner relaxation. To go further, we have modeled the BaTiO3 core-shell system using an effective Hamiltonian. The model shows that a new order parameter is observed in the core-shell system namely the toroidal moment. This order affects the dielectrics behavior of coated dots, and for important coating can lead to significant differences with Landau predictions. Moreover, by introducing the toroidal moment in Landau formalism, we can predict the disappearance of the orthorhombic phase in BaTiO3.The synthesis of homogenized cubic BaTiO3 particles, allowed us to make experimental measurement. The combination of RX, Dielectric and Raman measurements lead to a phase diagram for BaTiO3 that can be explain by the presence of a toroidal moment.

Orientador: Kamal Abdel Radi Ismail / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-16T09:00:11Z (GMT). No. of bitstreams: 1 Silva_RaqueldaCunhaRibeiroda_M.pdf: 5023080 bytes, checksum: 903e427adb9c620ee58193ecd5ca7371 (MD5) Previous issue date: 2010 / Resumo: O armazenamento de calor na forma de calor latente representa uma alternativa de grande potencial em sistemas intermitentes e de conservação. Uma das geometrias menos exploradas na literatura e no campo de aplicação é a geometria cilíndrica com aletas fixadas radialmente ao longo do tubo. As aletas neste caso representam dispositivos para aumentar a taxa de transferência de calor e assim a solidificação do PCM. Com o intuito de aumentar ainda mais a taxa de solidificação do PCM, a inserção de um promotor de turbulência ao longo do tubo, provoca maior agitação e turbulência que por sua vez aumenta o coeficiente de troca de calor e assim a taxa de solidificação do PCM. Assim este estudo visa investigar as influências dos parâmetros geométricos e operacionais sobre a velocidade da interface, tempo de solidificação completa e massa total solidificada e conseqüentemente a energia total armazenada. Na investigação experimental foram testados tubos com diversas aletas variando os diâmetros de 40 a 180 mm, várias vazões de fluido secundário e várias temperaturas de operação com e sem promotor de turbulência e com e sem aletas com o objetivo principal de quantificar os efeitos das aletas e promotor de turbulência sobre a taxa de solidificação ou velocidade da interface, tempo de solidificação completa e a massa solidificada total. Um programa numérico foi adaptado para simular o processo de solidificação em torno de tubo horizontal com aletas radiais. As medidas experimentais são usadas para validação do modelo e confirmar a possibilidade de sua utilização na previsão de desempenho desse tipo de arranjo de tubos. As medidas e as previsões numéricas mostram boa concordância estabelecendo assim a validade do modelo proposto / Abstract: The heat storage in the form of latent heat represents an alternative of great potential in intermittent systems and conservation. One of the geometries less explored in literature and in the field of application is to use a cylindrical geometry with radial fins fixed along the tube. The fins in this case represent devices to increase the rate of heat transfer and thus the solidification of the PCM. In order to further increase the rate of solidification of PCM, the insertion of a promoter of turbulence along the tube, causing further unrest and turmoil, which in turn increases the coefficient of heat exchange and thus the rate of solidification of PCM . So this study aims to investigate the influences of geometric and operational parameters on the interface speed, time to complete solidification and the total mass solidified and therefore the total energy stored. In the experimental investigation were tested with several fins tubes ranging from 40 to 180 mm, number of secondary fluid flow rates and various operating temperatures with and without turbulence promoter and with or without flaps with the main objective to quantify the effect of fins and promoter turbulence on the solidification rate or interface speed, time to complete solidification and total mass solidified. A numerical program was adapted to simulate the process of solidification around horizontal tube with radial vanes. The experimental measurements are used to validate the model and confirm the possibility of its use in forecasting performance of such an arrangement of tubes. Measurements and numerical predictions show good agreement thus establishing the validity of the proposed model / Mestrado / Termica e Fluidos / Mestre em Engenharia Mecânica

Orientador: Franco Giuseppe Dedini / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-17T03:50:36Z (GMT). No. of bitstreams: 1 Souza_ReynaldoBarrosde_M.pdf: 4185752 bytes, checksum: ed943a90ea99ae1eba06b60915cb20d9 (MD5) Previous issue date: 2010 / Resumo: Este trabalho tem como objetivo o estudo da tecnologia de veículos híbridos abrangendo os aspectos da propulsão e armazenamento de energia. O desenvolvimento de veículos com maior eficiência energética depende da análise das características de desempenho do veículo, bem como suas condições de utilização. O dimensionamento dos armazenadores de energia é considerado um desafio visto que, o sobredimensionamento da capacidade reduz a eficiência global do veículo, devido ao acréscimo de peso, enquanto que o subdimensionamento resulta numa utilização parcial do potencial de veículos híbridos. Através de um modelo de dinâmica veicular longitudinal serão realizadas simulações em três configurações de veículos e a comparação entre seus resultados. As forças requeridas no movimento de um veículo, resistência ao rolamento, resistência à inclinação e arrasto aerodinâmico, são dependentes do trajeto percorrido pelo usuário. As condições de utilização devem ser representadas em ciclos de condução padrão, utilizados em testes de emissões de poluentes e consumo de combustível, estes serão apresentados e discutidos. A partir das simulações realizadas são analisadas as demandas de potência e energia, provendo uma indicação dos benefícios de um sistema híbrido no desempenho e consumo de combustível. Observa-se uma redução expressiva no consumo energético e conseqüente menor utilização de combustível e menor custo de utilização, embora a tecnologia híbrida agregue um maior custo inicial / Abstract: This paper focus on the study of energy storage and management for hybrid electric vehicles. The development of higher efficiency vehicles depends on the analysis of vehicle performance characteristics and driving conditions. Sizing the energy capacity of the storage system, using batteries or other kinds of electric components, can be considered a big challenge once oversizing means inefficiency due to the increase of weight and undersizing results in partial use of hybrid advantages. The forces involved in a vehicle movement such as aerodynamic drag, rolling resistance and grading resistance, are fully dependent on the conditions of every possible course the driver might run, most situations should be represented on the driving pattern cycle, used for emissions and consumption tests, which will be presented and discussed. Modeling vehicle dynamic to analyze power and energy demand of each vehicle during different test cycles provides an indication of the benefits on hybrid system for performance and fuel consumption. . The results show a significant reduction on energy consumption and consequently also on driving costs / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica

Orientador: Oseas Valente de Avilez Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-05T03:19:21Z (GMT). No. of bitstreams: 1 Cardoso_PauloEduardodosReis_M.pdf: 801657 bytes, checksum: a93bd64d4f7bf3d70c8e568ab62f4385 (MD5) Previous issue date: 2005 / Resumo: Este trabalho apresenta o estudo realizado para a obtenção da correlação entre a Capacidade, que indica a capacidade de armazenamento eletroquímico de energia, e a Condutância, que mede componentes da resistência interna da bateria indicando o seu estado de degradação e envelhecimento. A obtenção do valor da capacidade requer um procedimento dispendioso, tanto em tempo como em recursos, enquanto que a condutância pode ser obtida rapidamente. Foram estudadas as técnicas para a avaliação do nível de confiabilidade de baterias a partir destes parâmetros, objetivando conhecer o estado da arte neste assunto. Também foram analisadas as metodologias de medição da resistência interna. O ensaio de envelhecimento realizado coletou dados de condutância e capacidade, durante cerca de um ano, de onde foi possível correlacionar estes dois parâmetros. O principal resultado desta correlação é a possibilidade de obtenção da capacidade a partir da medição rápida da condutância, com aplicação imediata nos procedimentos de manutenção preditiva de baterias chumbo-ácidas / Abstract: This text presents the study to obtain of the relationship between the Capacity, the indicated capacity of electrochemical storage of energy, and the Conductance, that measures the battery internal resistance components indicating its state of degradation and aging. The attainment of the value for the capacity requires an expensive procedure, as much in time as in resources, while that conductance can be gotten quickly. The level of trustworthiness techniques for the evaluation of batteries had been studied based on these parameters, being objectified to know the state of the art in this subject. Also the internal resistance measurement methodologies had been analyzed. The aging test given conductance and capacity, during about one year, made possible to correlate these two parameters. The main result of this correlation is the possibility of attainment of the capacity from the fast measurement of the conductance, with immediate application in the procedures of predictive maintenance of lead-acid batteries / Mestrado / Eletrônica, Microeletrônica e Optoeletrônica / Mestre em Engenharia Elétrica

Orientadores: Ennio Peres da Silva, Newton Pimenta Neves Junior / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-20T12:25:52Z (GMT). No. of bitstreams: 1 Furlan_AndreLuis_D.pdf: 2850462 bytes, checksum: cf9586ce36bd523119ff4727d43989f7 (MD5) Previous issue date: 2012 / Resumo: Este trabalho faz uma análise técnico-econômica do uso do hidrogênio como meio armazenador de energia elétrica proveniente de fonte eólica, cuja natureza imprevisível do vento não pode garantir sua quantidade de energia elétrica ofertada. Para resolver este problema, foram propostos dois sistemas de armazenamento operando de modos diferentes, para os quais foi desenvolvido um modelo matemático para o dimensionamento deles, implementado numa planilha eletrônica, no qual foram consideradas as principais características e eficiências dos equipamentos que compõem os sistemas, bem como a garantia física característica da usina eólica. A seguir, foi realizada uma análise econômica dos sistemas tendo sido verificado que o custo de produção da energia elétrica a partir do primeiro modo de operação proposto foi aproximadamente 47,5% maior que o custo de produção de energia da usina eólica sem armazenamento (130 R$/MWh) e, considerando o segundo modo, a diferença foi 92% maior. No caso da energia elétrica gerada pela célula a combustível o valor obtido foi de 1.180,00 R$/MWh e 1.250,00 R$/MWh considerando, respectivamente, o primeiro e segundo modo de operação / Abstract: The current work aims to present a technical-economical analysis of the use of hydrogen as a means to store energy generated by wind power systems, since the wind regime is unpredictable and thus there is no guarantee for the amount of power offered. First of all, two storage systems were proposed and a mathematical model was established considering the main features and efficiencies of the equipment that compose the systems as well as the wind power energy guarantee. Secondly, an economic analysis of those systems was carried out. The cost of power generation for the first mode of operation was approximately 47,5% larger than that of a similar wind power system without storage (130 R$/MWh) and, concerning the second mode, the power cost was 92% larger. Regarding the energy generated by the fuel cell only, the power cost was respectively 1.180,00 R$/MWh and 1.250,00 R$/MWh for each of the operation modes / Doutorado / Engenharia Mecanica / Doutor em Planejamento de Sistemas Energéticos