Orientador: Ennio Peres da Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-12T22:42:24Z (GMT). No. of bitstreams: 1 Ferreira_PauloFabricioPalhavam_M.pdf: 1604656 bytes, checksum: f806501ef39092fe041981d1e41774c3 (MD5) Previous issue date: 2003 / Resumo: Neste trabalho foram analisadas as viabilidades técnica e econômica de sistemas de rodução de hidrogênio eletrolítico utilizando energia elétrica fora do horário de ponta e, reconversão deste hidrogênio em eletricidade durante o horário de ponta utilizando células a combustível. Para tanto foi construído um sistema piloto de produção e reconversão de hidrogênio com a finalidade de determinar-se as melhores condições de operação e eficiência energética para cada componente do sistema. Os resultados obtidos foram utilizados para uma análise econômica de viabilidade destes sistemas para uso industrial. Como resultados foram obtidas uma eficiência energética global de 16,4% e, para grandes diferenças de tarifa elétrica entre a ponta de carga e fora dela, foi encontrada a possibilidade da utilização desse tipo de sistema em industrias de médio e grande porte / Abstract: This work analyses the technical and economical viability of electrolytic hydrogen generation systems which used power during off-peak power demand and reconverted the energy stored in the form of hydrogen during peak hours by means of fuel cells. For this purpose, a pilot system for producing and reconverting hydrogen was built in order to determine the best operating conditions and power efficiency for each component if the system. The results obtained were used for the economical viability analysis of these systems in industrial use. For the pilot system analyzed, the results show a global energy efficiency of 16.4% and, for significant differences between the peak and off-peak power tariffs, that this kind of system may be used in medium and large companies / Mestrado / Mestre em Planejamento de Sistemas Energéticos

Fresh water shortage and hot weather are common challenges in many countries of the world. In the other hand, the air conditioning systems which are used for indoor cooling cause peak electricity demand during high temperatures hours. This peak hour demand is very important since it is more expensive and mainly is supplied by fossil fuel power plants with lower efficiencies compare to base load fossil fuel or renewable owe plants. Moreover, these peak electricity load fossil fuel power plants cause higher green house gas emission and other environmental effects. So, all these show that any solution for these problems could make life better in those countries and all over the world.In this thesis, a new idea for a Power storage, Cooling storage, and Water production Combined Cycle (PCWCC) is introduced and reviewed. PCWCC is combination of two thermal cycles, Ice Thermal Energy Storage (ITES) and desalination by freezing cycle, which are merged together to make a total solution for fresh water shortage, required cooling, and high peak power demand. ITES is a well known technology for shifting the electricity demand of cooling systems from peak hours to off-peak hours and desalination by freezing is a less known desalination system which is based on the fact that the ice crystals are pure and by freezing raw water and melting resulted ice crystals, pure water will be produced. These two systems have some common processes and equations and this thesis shows that by combining them the resulted PCWCC could be more efficient than each of them. In this thesis, the thermodynamic equations and efficiencies of each PCWCC sub-systems are analyzed and the resulted data are used in finding thermodynamics of PCWCC itself. Also, by using reMIND software, which uses Cplex to find the best combinations of input/output and related processes, the cost of produced fresh water and cooling from PCWCC is compared with total cost of fresh water and cooling produced by each sub-systems of PCWCC in three sample cities all over the world, Kerman, Dubai, and Texas. These cities are chosen since they have similar ambient temperature trend with different electricity and fresh water tariff's. The results show that, the PCWCC is economical where there is a significant electricity price difference between ice charging and ice melting hours, off-peak and peak hours, of the day or when the fresh water price is high compare to electricity price. The results also show that how the revenue from fresh water could cover the used electricity cost and make some income as well.

Diese Dissertation untersucht Fragen, die sich mit dem Einfluss der Übertragungskapazitäten und der Erzeugung erneuerbarer Energien auf dem Strommarkt befassen. Die Arbeit besteht aus drei eigenständigen Aufsätze, die für die politische Debatte einen Beitrag leisten. Das erste Kapitel konzentriert sich auf ein Netzwerk mit strategischen Unternehmen, die die Stromflüsse zu ihrem Vorteil manipulieren können. Dieses Kapitel gehört zur Forschungsliteratur, die Strommärkte als Gleichgewichtsprobleme mit Gleichgewichtseinschränkungen darstellt. In diesem Rahmen vergleiche ich mehrere Strategien zur Stärkung des Wettbewerbs und zeige, dass der Netzausbau zwar den Wettbewerb ankurbeln kann, mit Umstrukturierungen aber größere Verbesserungen des Verbraucherüberschusses und des Wohlstands erzielt werden können. Das zweite Kapitel basiert auf einem ähnlichen Modell mit einem einfachen Zwei-Knoten-Netzwerk. Dieser Ansatz zeigt mögliche nachteilige Auswirkungen (höhere Preise, geringerer Gesamtverbrauch, geringerer Konsumentenrente) einer höheren Einspeisung erneuerbarer Energie in einem Netz, in dem eine Region mit hohem erneuerbaren Potenzial von einer Region mit hoher Last durch eine begrenzte Übertragungskapazität getrennt ist. Die Annahme ist, dass es in jeder Region einen strategischen Akteur gibt, der seine Marktmacht ausübt. Das dritte Kapitel befasst sich mit der Substitution zwischen Übertragungs- und Speicherkapazitäten - beides Instrumente zur Integration von erneuerbarer Energien. Eine Analyse mit einfachen Speicherheuristik zeigt den relativ bescheidenen Effekt des zeitlichen Ausgleichs. Im Gegensatz dazu birgt die Erweiterung des Übertragungsnetzes ein erhebliches Steigerungspotenzial für die Nutzung erneuerbarer Energiequellen, die Verringerung der Kürzungsraten und die Reduzierung der minimalen konventionellen Stromerzeugung. / This thesis investigates several questions related to the influence of transmission capacities and generation of renewable energy on the outcomes in the wholesale electricity markets. The thesis consists of three self-contained essays that contribute to the policy debate. The analysis of the first essay focuses on a network with strategic firms that can manipulate power flows to their advantage. Methodologically, this chapter belongs to the research literature that represents electricity markets as equilibrium problems with equilibrium constraints. In this framework I compare several policies of enhancing competition and demonstrate that although network expansion can stimulate competition, larger improvements in consumer surplus and welfare can be achieved with restructuring. The second essay is based on a similar model, but in a stylized two node network. This approach demonstrates potential adverse effects (higher prices, lower total consumption, lower consumer surplus) from higher renewable infeed in a network where a region with high renewable potential is separated from a region with high load by a limited transmission capacity. I adopt a worst-case assumption that in each region there is a strategic player exercising its market power. The third essay studies the substitution between transmission and storage expansion - two instruments for the integration of expanding renewable energy. Using a myopic storage heuristic I demonstrate the relatively modest effect of temporal balancing of renewable power. In contrast, transmission expansion has a significant potential in increasing renewable penetration, mitigating curtailment rates, and reducing the minimum conventional generation power at any hour. If Europe is to pursue the high targets of renewable power in electricity consumption, the only way to avoid the expansion of cross border lines is extremely high installed renewable capacities and energy capacities of storage.

La micro cogénération désigne la génération simultanée de deux types d’énergie à faible puissance. En énergétique, ce terme désigne en pratique la production simultanée d’électricité et de chaleur : le principe reposant sur la récupération de la chaleur fatale induite par la production électrique. Deux bancs d’essais ont d’abord été réalisés sur deux prototypes de micro cogénérateurs : un moteur Stirling à gaz et un moteur à vapeur à granulés de bois. Une campagne expérimentale a été menée pour caractériser chaque système au niveau énergétique et environnemental. Les résultats expérimentaux ont abouti sur deux modèles numériques dynamiques et semi-physiques de micro cogénérateurs programmés dans l’environnement numérique TRNSYS où une plateforme numérique de simulation a été développée. Celle-ci intègre principalement des modèles de systèmes de stockage d’énergie, des générateurs stochastiques de fichiers de besoins énergétiques et des stratégies innovantes de pilotage des systèmes et des charges selon des critères de précision et de réalisme.Cette plateforme a permis d’évaluer la pertinence énergétique, environnementale et économique de micro cogénérateurs couplés aux bâtiments d’habitation et au réseau électrique selon différentes configurations. / Micro combined heat and power (µCHP) or cogeneration means the simultaneous generation of two energy types. In energetic fields, this term refers usually to the simultaneous production of electricity and heat: the principle being based on the recovering of the fatal heat induced by the electricity production processes.Firstly, two test benches were carried out on two µCHP prototypes: a gas Stirling engine and a wood pellets steam engine. Experimental investigations were conducted to characterize each system at energy and environmental levels. The experimental results led two dynamic and semi physical numerical models of µCHP systems programmed in the numerical tool TRNSYS where a numerical platform has been developed. This platform integrates mainly energy storage systems models, stochastic energy needs file generators and innovative management strategy of systems and energy loads according to precision and realism criteria.This platform allows assessing realistic energy, environmental and economic relevance of µCHP systems coupled with dwelling buildings and the power grid according to different configurations.