This diploma thesis deals with possibilities of accumulation of electricity generated by renewable sources with unstable production. Several goals were set by an assignment of this thesis. Within a research, current trends of the accumulation are presented in detail on examples of specific representatives with their technical parameters and economic possibilities. Further, an unstable source of electricity – the wind farm of three power plants Multibrid 5000 with all its parameters and operational details is defined for purposes of individual designs of accumulation systems. Firstly, the detailed design of an advanced compressed air energy storage (A-CAES) is realized. It includes a thermodynamic calculation of chosen components, their partial technical solutions, a financial evaluation of investment and a determination of theoretical payback period. Furthermore, the design for accumulators Tesla Powerpack is realized. It contains a calculation of individual system parameters, a financial evaluation of investment and a determination of theoretical payback period. Last part of the thesis is dedicated to a comparison and an evaluation of the achieved results of both realized methods of the electricity accumulation. In the end, A-CAES is chosen as more perspective variation.

This thesis is focused on demonstrating the impact of the implementation of decentralized distributed energy sources (mainly RES) and electromobility technologies to electrical parameters in Czech medium voltage distribution network. Thesis is divided into two main chapters. First one is a brief theoretical summary of this problematic and the second one is a practical software simulation on a real medium voltage network. Proposed implementation scenarios are based on EU and national strategic plans for time period from 2020 to 2040.

The main goal of the diploma thesis is to design a new ventilation and heating system in an old house after its reconstruction. The design also includes consideration of the possibility of using renewable resources. A central heat recovery ventilation systém is designed to ensure ventilation of the building. The heating design is based on two independent heat sources. It is a wood boiler and a gas condensing boiler. After considering renewable sources, a photovoltaic system is designed. The results of individual calculations and drawing documentation of designs are also attached.

This Master’s thesis´ topic is “Business Plan Proposal: Photovoltaic Power Plant” and it has been assigned at Brno University of Technology, Faculty of Business and Management. The target is to create business plan proposal based on real business case that would be actually used not only as summary of all the necessary information for the project owner but also as information source for potential investors and other stakeholders of the project. Except the above mentioned, thesis demonstrates the knowledge of the energetic sector’s environment, ability to implement the legislation, use particular managerial tools and to prepare the technical and economical valuation to make decision making easier and to catch the investors´ eyes. The project concerns construction and operation of the photovoltaic power plant in the Czech Republic.

The aim of this diploma work is the study and the modeling of an Organic Rankine Cycle (ORC). Organic Rankine Cycle is used for heat recovery from low-potential heat sources. Their working fluid is a refrigerant or a hydrocarbon whose properties are adapted to the conditions in which the heat recovery is performed. The other chapters include the technical resolution of exhaust-heat exchanger of cogeneration unit for application ORC and partially economic study use in Czech Republic.

Master thesis deals with photovoltaic components and their principles. Evaluate the types of photovoltaic systems and their impact on the transmission system. The thesis deals with financial support to small and micro-photovoltaic systems, which can be used in terms of legislation of the Czech Republic. There are also described the changes in the amendment to the energy act and effect on the price of electricity in households. Compared with the domestic photovoltaic rest of the world and the view of the German energy concept. Part of the theoretical design of a hybrid photovoltaic plant, including the use of heat pump. Thesis deals with using hybrid photovoltaic plant and economic viability of the proposed system. The last part deals with the implementation of the proposed system and assesses the true value from those anticipated in the design.

The development of new communities to facilitate the growing population isan ongoing trend, with locations outside the city limits so as to have morearea and less pollution. The main need in isolated communities is to secureenergy demand, which is normally done with power supply from the maingrid, which will require new transmission lines and transformer installation,among other things. As we strive for net-zero energy buildings, the energysource should be renewable and clean. So far, the most common andefficient renewable sources available in abundance are solar and windpower. So, based on the location, we investigate how we can make thesystem of combined solar, and wind power a successful energy source sothat the load of the community can be fulfilled while at the same time thepower from the main grid is isolated. This analysis is done for off-gridsystems to analyze a combined Solar and Wind energy production andcalculate the needed storage, also presenting a comparison with Dieselbased generation and an Economical perspective,for the different locations.As an output of this analysis a program has been developed to examineother locations on bases of local load data.

The world is currently submerged in two big problems: supply energy crisis and climate change. It is clear that society has to do its best to overcome these challenges, and one effective way to mitigate their effects is by conducting an energy audit, which helps to identify the weaknesses and strengths of the buildings, enabling improvements in their thermal efficiency.  The main goal of this study was to carry out an energy audit on a century-old single- family house located in a city in the middle of Sweden. To achieve this, relevant data of the building was gathered such as the bills and some temperature and dimension measurements. Subsequently, the calculations of the energy losses and gains were done manually. From this step it was observed that almost 70 % of the thermal losses occurred due to transmission through the walls, windows and roof. To reduce these losses, potential energy-saving measures were studied, such as replacing the 2-panel windows with 3-panel windows and adding 200 mm of mineral wool to the roof. Both improvements reduced transmission losses around 700 kWh/year and diminished CO2 emissions around 20 kg/year, which implied a decrease of 1262 and 1277 SEK per year for each measure respectively. However, the profitability of these measures was difficult to attain because the required initial capitals are probably higher than the investments allowed, which are around 17371 and 17579 SEK for each measure respectively.  Moreover, a study about installing photovoltaic solar cells was conducted and it resulted in a significant positive impact in the energy usage of the house. In particular, this improvement lead to a reduction of 2471 kWh per year, which equaled to an annual decrease of 6036 SEK. These annual savings implied an investment allowed of 58620 SEK. Furthermore, a decrease of 99 kg of CO2 emissions per year was obtained. In conclusion, this measure yielded substantial profitability, making it the most recommended option for future energy-saving improvements.  Finally, changing in the occupant’s behavior by reducing the indoor temperature had a positive impact on the house without the need for an initial investment. Specifically, it decreased around 105 kWh per year.

[pt] O aumento da participação de fontes de energias renováveis variáveis (ERVs) na matriz elétrica do Brasil traz diversos desafios ao planejamento e à operação do Sistema Elétrico Brasileiro (SEB), devido à estocasticidade das ERVs. Tais desafios envolvem a modelagem e simulação dos processos intermitentes de geração e, dessa forma, um volume considerável de pesquisas tem sido direcionado ao tema. Nesse contexto, um tópico de crescente importância na literatura relaciona-se ao desenvolvimento de metodologias para simulação estocástica conjunta de recursos intermitentes com características complementares, como, por exemplo, as fontes eólica e solar. Visando contribuir com essa temática, este trabalho propõe melhorias a um modelo de simulação já estabelecido na literatura, avaliando sua aplicabilidade a partir de dados do Nordeste brasileiro. A metodologia proposta baseia-se em discretização das séries temporais de energia aplicando a técnica de machine learning k-means, construção de matrizes de transição de estados com base nos clusters identificados e simulação de Monte Carlo para obtenção dos cenários. As séries sintéticas obtidas são comparadas aos resultados gerados pelo modelo já estabelecido na literatura a partir de técnicas estatísticas. Quanto ao alcance dos objetivos da pesquisa, a modelagem proposta se mostrou mais eficiente, gerando cenários que reproduziram satisfatoriamente todas as características dos dados históricos avaliadas. / [en] The increased participation of variable renewable energy sources (VRES) in Brazil s electricity matrix brings several challenges to the planning and operation of the Brazilian Power System (BPS), due to the VRES stochasticity. Such challenges involve the modeling and simulation of intermittent generation processes and, in this context, a considerable amount of research has been directed to the theme. In this context, a topic of increasing importance in the literature is related to the development of methodologies for joint stochastic simulation of intermittent resources with complementary characteristics, such as wind and solar sources. Aiming to contribute to this theme, this work proposes improvements in a simulation model already established in the literature, evaluating its applicability based on Brazilian Northeast data. The proposed methodology is based on the discretization of energy time series applying the kmeans machine learning technique, construction of state transition matrices based on the identified clusters, and Monte Carlo simulation to obtain the scenarios. The synthetic series obtained are compared to the results generated by the model already established in the literature from statistical techniques. Regarding the scope of the research objectives, the proposed modeling demonstrated more promising results, generating scenarios that satisfactorily reproduced all the evaluated characteristics of the historical data.

[pt] Fontes renováveis são importantes recursos a serem agregados aos sistemas de energia elétrica em prol da descentralização da geração. Discussões acerca dos efeitos ambientais direcionam os estudos em busca de alternativas que possibilitem minimizar a emissão de gases poluentes e diversifiquem a matriz elétrica. Nesse contexto, a geração distribuída (GD) de natureza renovável vem se mostrando cada vez mais presente, alterando a estrutura clássica do sistema e conferindo um maior protagonismo do consumidor. Assim, torna-se essencial avaliar o desempenho dessas novas redes de distribuição no atendimento à demanda, de modo a estabelecer padrões adequados e monitorá-los através das agências reguladoras. Há uma diversidade de métodos de avaliação do desempenho dessas redes, principalmente através dos conceitos de confiabilidade, para lidar com as falhas de equipamentos e os efeitos decorrentes. A presente tese tem como objetivo avaliar índices de confiabilidade de sistemas de distribuição na presença de GD. Para isso, são apresentadas três técnicas baseadas em simulação Monte Carlo (SMC). Uma clássica, denominada SMC sequencial, tem como objetivo modelar a natureza cronológica do problema bem como as incertezas provenientes da intermitência de fontes de GD. A segunda, baseada na SMC quase sequencial, caracteriza-se por sua simplicidade e capacidade em manter a flexibilidade da SMC sequencial, porém, com melhor desempenho em termos de precisão e tempo de processamento. Por último, uma SMC baseada nos conceitos de transição de estado do sistema de forma cronológica assegura também precisão e flexibilidade à técnica. Novas funções teste são propostas para alcançar tal objetivo. Dois sistemas com inserção de GD são utilizados para avaliar o desempenho dos conceitos e técnicas propostas: IEEE RBTS, rede acadêmica padrão amplamente utilizada na área de confiabilidade; e uma rede real. A discussão exaustiva dos resultados confirma que as propostas cumprem os objetivos estabelecidos. / [en] Renewable sources are important resources to be added to electrical energy systems in favor of decentralized generation. Discussions about environmental effects drive the studies in search of alternatives that make it possible to minimize the emission of polluting gases and diversify the electrical matrix. In this context, distributed generation (DG) of a renewable nature has been increasingly present, changing the classic structure of the system and giving greater engagement to the consumer. Therefore, it is essential to evaluate the performance of these new distribution grids in meeting the power demand, in order to establish appropriate standards and monitor them through the regulatory agencies. There is a diversity of methods for evaluating the performance of these networks, mainly through reliability concepts, to deal with equipment failures and the resulting effects. This thesis aims to evaluate reliability indices of distribution systems in the presence of DG. To this end, three techniques based on Monte Carlo simulation (MCS) are presented. A classic one, called sequential MCS, aims at modeling the chronological nature of the problem as well as the uncertainties arising from the intermittency of the DG sources. The second one, based on a quasi-sequential MCS, is characterized by its simplicity and ability to maintain the flexibility of sequential MCS, but with better performance in terms of precision and processing time. Finally, an MCS based on the concepts of chronological system state transition, also provides precision and flexibility to the reliability assessment. New test functions are proposed to achieve this goal. Two systems with DG insertion are used to evaluate the performance of the proposed concepts and techniques: IEEE RBTS, a standard academic network widely used in the reliability area; and another real network. The exhaustive discussion of the results confirms that both proposals meet the established objectives.