O aumento da população e o desenvolvimento da economia criam a necessidade de expansão de mais de quatro mil Megawatts da energia nova por ano no Sistema Interligado Nacional (SIN). O sistema elétrico brasileiro é peculiar, devido a sua grande capacidade, extensão continental e grande dependência na energia renovável hídrica. Outra peculiaridade é a capacidade potencial de inserção de outras formas da energia renováveis “verdes” no sistema. Embora as vantagens ambientais das energias renováveis, elas têm limitações, são variáveis e dependentes das condições climáticas. Para que o setor elétrico brasileiro possa atuar com confiabilidade com mais energia renovável deve haver concomitante mais energia firme de origem térmica disponível. Assim o trabalho analisa, na perspectiva global, o estado da arte e as tendências das fontes de geração elétrica, sob o ponto de vista de disponibilidade, preço e sustentação ambiental. De forma especial, o trabalho analisa as opções de geração térmica no Brasil. Conclui pela necessidade do Brasil priorizar o uso dos recursos disponíveis dentro de suas fronteiras como o carvão mineral para garantir a geração térmica elétrica auto-suficiente. O trabalho demonstra as vantagens sociais e de desenvolvimento de uma indústria do carvão para as regiões produtoras. Aponta também a necessidade de implementação de tecnologias modernas a fim de atender à legislação ambiental, que gradativamente deve aumentar as restrições das emissões poluentes, na medida em que as tecnologias forem desenvolvidas. / The population and economy growth in Brazil generate the necessity of an expansion higher than four thousand Megawatts of new electric energy per year. The Brazilian Electrical System is peculiar because of its continental extension and also its strong dependence in renewable energy (hydro). Another reason for its peculiarity is the potential of inserting other forms of renewable and “green” energy in the system. Although the environmental advantages of the “renewable”, these kinds of energies are variable and dependant of the weather conditions. In order to the electrical system be more reliable, its operation must be combined with a larger addition of thermal energy. Thus this report analyses thermal generation option in Brazil. Looking at the developed countries trends in diversify power generation, the article indicates the advantages and the priority of using, in Brazil, internal resources like coal to guarantee the self-sufficient thermal generation electrical capacity. The dissertation demonstrates the social advantages to develop the coal industry for the producers region, witch are poor areas in Brazil. The proposition points the need of implement modern technologies in order to attend the environmental legislation, which must increase the emissions restrictions as these technologies are developed.

Residential space and water heating accounts for around 13% of the greenhouse gas emissions of the UK. Reducing this is essential for meeting the national emission reduction target of 80% by 2050 from the 1990 baseline. One of the strategies adopted for achieving this is focused around large scale shift towards electrical heating. This could lead to unsustainable disparity between the daily peak and off-peak electricity loads, large seasonal variation in electricity demands, and challenges of matching the short and long term supply with the demands. These challenges could impact the security and resilience of UK electricity supply, and needs to be addressed. Rechargeable Thermal Energy Storage (TES) in residential buildings can help overcome these challenges by enabling Heat Demand Shifts (HDS) to off-peak times, reducing the magnitude of the peak loads, and the difference between the peak and off-peak loads. To be effective a wide scale uptake of TES would be needed. For this to happen, the benefits and impacts of TES both for the demand side and the supply side have to be explored, which could vary considerably given the diverse physical, thermal, operational and occupancy characteristics of the UK housing stock. A greater understanding of the potential consequence of TES in buildings is necessary. Such knowledge could enable appropriate policy development to help drive the uptake of TES or to encourage development of alternative solutions. Through dynamic building simulation in TRNSYS, this work generated predictions of the space and water heating energy and power demands, and indoor temperature characteristics of the UK housing stock. Twelve building archetypes were created consisting of: Detached, semi-detached, mid-terrace and flat built forms with thermal insulation corresponding to the 1990 building regulation, and occupied floor areas of 70m2, 90m2 and 150m2. Typical occupancy and operational conditions were used to create twelve Base Case scenarios, and simulations performed for 60 winter days from 2nd January. HDS of 2, 3 and 4 hours from the grid peak time of 17:00 were simulated with sensible TES system sizes of 0.25m3, 0.5m3 and 0.75m3, and water storage temperatures of 75°C and 95°C. Parametric analysis were performed to determine the impacts and benefits of: thermal insulation equivalent to 1980, 1990 (Base Case), 2002 and 2010 building regulation; locations of Gatwick (Base Case) and Aberdeen; heating durations of 6, 9 (Base Case), 12 and 16 hours per day; thermostat settings of 19°C, 21°C (Base Case) and 23°C, and number of occupiers of 1 person and 3 persons (Base Case) per household. Good correlation was observed between the simulated results and published heat energy consumption data for buildings with similar thermal, physical, occupancy and operational conditions. The results allowed occupied space temperatures and overall daily and grid peak time energy consumption to be predicted for the range of building archetypes and parameter values considered, and the TES size necessary for a desired HDS to be determined. The main conclusions drawn include: The overall daily energy consumption predictions varied from 36.8kWh to 159.7kWh. During the critical grid peak time (17:00 to 21:00) the heat consumption varied from 4.2kWh to 58.7kWh, indicating the range of energy demands which could be shifted to off-peak times. On average, semi-detached, mid-terrace, and flat built forms consumed 7.0%, 13.8% and 22.7% less energy for space heating than the detached built form respectively. Thermal insulation changing from the 1990 building regulation level to the 1980 and 2010 building regulation levels could change the mean energy use by +14.7% and -19.6% respectively. A 0.25m3 TES size with 75°C water storage temperature could enable a 2 hour HDS, shifting 4.3kWh to 11.7kWh (mean 8.7kWh) to off peak times, in all 70m2 Base Case archetypes with the 60 day mean thermal comfort of 100%, but with the minimum space temperature occasionally dropping below an 18°C thermal comfort limit. A 0.5m3 TES size and water storage of 95°C could allow a 3 hour HDS, shifting 9.8kWh to 28.2kWh (mean 18.7kWh) to off peak times, in all 90m2 Base Case archetypes without thermal comfort degradation below 18°C. A 0.75m3 TES with a 95°C water temperature could provide 4 hour HDS, shifting 13.9kWh to 47.7kWh (mean 27.2kWh) to off peak times, in all 150m2 Base Case archetypes with 100% mean thermal comfort but with the 60 day minimum temperature occasionally dropping below the 18°C thermal comfort limit in the detached built form. Improving the thermal insulation of the buildings was found to be the best way to improve the effectiveness of HDS with TES, in terms of the demand shift period achievable with minimal thermal comfort impact. A 4 hour HDS with 100% thermal comfort is possible in all 90m2 floor area buildings with a 0.25m3 tank and a water storage temperature of 75°C provided that the thermal insulation is as per 2010 building regulation. Recommendations for further research include: 1) creating larger number of archetype models to reflect the housing stock; 2) using heat pumps as the heat source so that the mean effect on the grid from electric heating loads can be predicted; 3) taking into account the costs associated with taking up HDS with TES, in terms of capital expenses and space requirement for housing the TES system; 4) considering alternative methods of heat storage such as latent heat storage to enhance the storage capacity per unit volume; and 5) incorporating zonal temperature control, for example, only heating rooms that are occupied during the demand shift period, which could ensure better thermal comfort in the occupied space and extend the demand shift period.

Made available in DSpace on 2015-07-13T12:10:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-03-04. Added 1 bitstream(s) on 2015-07-13T12:25:41Z : No. of bitstreams: 1 000832971.pdf: 1514299 bytes, checksum: 29a4cd55e16ecdbaead264c825fb9957 (MD5) / A disponibilidade de luz solar, transformada em energia, pode ser capturada em quase todo o mundo. Desde a década de 1990 o mercado da utilização de energia solar vem crescendo, porém informações sobre estudos de caso para a avaliação da inserção de aquecedores solares de água nos domicílios populares brasileiros ainda são escassas. O presente trabalho visa contribuir para reduzir essa carência e tem como objetivo avaliar a viabilidade técnica e econômica da inserção de aquecedores solares de água nas residências populares no município de Tremembé, localizado no Vale do Paraíba, estado de São Paulo, Brasil. O município de Tremembé possui uma área de 192 km² e conta com uma população de 42.027 habitantes, sendo um total de 10.632 domicílios. A avaliação foi efetuada numa amostra setorial do total de domicílios, através de um plano amostral aleatório estratificado, metodologia que permite conhecer melhor as características próprias de cada setor do município estudado. A pesquisa de campo foi efetuada com o método survey, com o total de 360 questionários, os quais foram aplicados a um representante de cada família. Imagens com as descrições e atributos dos setores censitários do IBGE foram tratadas no formato de extensão kmz. Foi necessária a construção de um cadastro no programa Excel para inserir os dados colhidos em campo e esses dados foram sobrepostos aos layers das imagens tratadas. O resultado desta pesquisa mostrou aceitação generalizada da população à possibilidade de instalações e utilização de sistemas de aquecimento solar de água, especialmente nas áreas rurais, principalmente por apresentar custo reduzido de energia elétrica no pico e aponta para a redução da demanda na rede elétrica. A pesquisa comprova que com a utilização de energia solar, o município pode economizar 31.680.000 kWh/ano, o que corresponde a R$ 9.504.000,00 /ano / The availability of sunlight converted into energy can be captured throughout the world. Since the 1990s the market for the use of solar energy has been growing, but information on case studies to assess the inclusion of solar water heaters in the popular Brazilian households are still scarce. The present work aims at contributing to reduce this gap and aims to assess the technical and economic feasibility of integration of solar water heaters in low-income households in the municipality Tremembé, located in the Paraíba Valley, State of São Paulo, Brazil. Tremembé has an area of 192 km ² and has a population of 42,027 inhabitants, with 10,632 households. The evaluation has done on a sectorial sample of total households. Effected through a stratified aleatory sampling plan, as this methodology allows better understanding the characteristics of each sector of the municipality. The field research was conducted with the survey method, with 360 questionnaires, which have been applied to a representative of each family. Images with descriptions and attributes of the official census sectors of IBGE have been treated in the extension kmz format. It was necessary to build a register in Excel to insert the data collected in the field and these data were overlaid on the images Leyers treated. The result of this research showed widespread acceptance of the population the possibility of facilities and use of solar water heating systems, especially the rural areas, mainly by presenting reduced cost of electric power in peak and points to reduced demand in the power grid. The research proves that with the use of solar energy, the city may save 31, 68 million kWh/year, which corresponds to R$ 9,504,000.00/ year

O aumento da população e o desenvolvimento da economia criam a necessidade de expansão de mais de quatro mil Megawatts da energia nova por ano no Sistema Interligado Nacional (SIN). O sistema elétrico brasileiro é peculiar, devido a sua grande capacidade, extensão continental e grande dependência na energia renovável hídrica. Outra peculiaridade é a capacidade potencial de inserção de outras formas da energia renováveis “verdes” no sistema. Embora as vantagens ambientais das energias renováveis, elas têm limitações, são variáveis e dependentes das condições climáticas. Para que o setor elétrico brasileiro possa atuar com confiabilidade com mais energia renovável deve haver concomitante mais energia firme de origem térmica disponível. Assim o trabalho analisa, na perspectiva global, o estado da arte e as tendências das fontes de geração elétrica, sob o ponto de vista de disponibilidade, preço e sustentação ambiental. De forma especial, o trabalho analisa as opções de geração térmica no Brasil. Conclui pela necessidade do Brasil priorizar o uso dos recursos disponíveis dentro de suas fronteiras como o carvão mineral para garantir a geração térmica elétrica auto-suficiente. O trabalho demonstra as vantagens sociais e de desenvolvimento de uma indústria do carvão para as regiões produtoras. Aponta também a necessidade de implementação de tecnologias modernas a fim de atender à legislação ambiental, que gradativamente deve aumentar as restrições das emissões poluentes, na medida em que as tecnologias forem desenvolvidas. / The population and economy growth in Brazil generate the necessity of an expansion higher than four thousand Megawatts of new electric energy per year. The Brazilian Electrical System is peculiar because of its continental extension and also its strong dependence in renewable energy (hydro). Another reason for its peculiarity is the potential of inserting other forms of renewable and “green” energy in the system. Although the environmental advantages of the “renewable”, these kinds of energies are variable and dependant of the weather conditions. In order to the electrical system be more reliable, its operation must be combined with a larger addition of thermal energy. Thus this report analyses thermal generation option in Brazil. Looking at the developed countries trends in diversify power generation, the article indicates the advantages and the priority of using, in Brazil, internal resources like coal to guarantee the self-sufficient thermal generation electrical capacity. The dissertation demonstrates the social advantages to develop the coal industry for the producers region, witch are poor areas in Brazil. The proposition points the need of implement modern technologies in order to attend the environmental legislation, which must increase the emissions restrictions as these technologies are developed.

abstract: This thesis examines using thermal energy storage as a demand side management tool for air-conditioning loads with the goal of increasing photovoltaic penetration. It uses Arizona State University (ASU) as a case study. The analysis is completed with a modeling approach using typical meteorological year (TMY) data, along with ASU’s historical load data. Sustainability, greenhouse gas emissions, carbon neutrality, and photovoltaic (PV) penetration are all considered along with potential economic impacts. By extrapolating the air-conditioning load profile from the existing data sets, it can be ensured that cooling demands can be met at all times under the new management method. Using this cooling demand data, it is possible to determine how much energy is required to meet these needs. Then, modeling the PV arrays, the thermal energy storage (TES), and the chillers, the maximum PV penetration in the future state can be determined. Using this approach, it has been determined that ASU can increase their solar PV resources by a factor of 3.460, which would amount to a PV penetration of approximately 48%. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2016

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

Orientador: Vicente Luiz Scalon / Coorientador: Alcides Padilha / Banca: Ismael de Marchi Neto / Banca: Celso Luiz da Silva / Resumo: Atualmente, a aplicação da energia solar térmica para aquecimento de água é uma solução técnica e economicamente viável permitindo a redução do consumo de energia elétrica no setor residencial, comercial e industrial. Diante disto, se faz cada vez mais necessário o domínio de metodologias que permitam quantificar a energia térmica útil captada pelos coletores solares e determinar a sua eficiência na geração de água quente. Como uma forma de contribuir para esta meta, este trabalho desenvolve uma análise comparativa da captação de energia térmica no coletor solar plano. A partir de dados experimentais e teóricos, diferentes modelos para tratamento dos dados foram aplicados e comparados. A metodologia do trabalho consistiu em monitorar um sistema de aquecimento solar residencial, em condições reais de uso e, a partir dos dados obtidos, calcular e comparar a captação de energia térmica útil nos coletores solares baseando-se no balanço energético pela Primeira Lei da Termodinâmica e pelo Método de Eficiência Térmica Instantânea. A irradiação solar global incidente nas placas da placa solar plano também foi monitorada e, portanto, seu valor foi comparado ao modelo teórico. Por fim, a demanda mensal de energia térmica para consumo de água quente da residência também foi monitorada e comparada à captação mensal de energia. A aplicação mostrou coerência entre os resultados experimentais e teóricos em grande parte dos casos, algumas inconveniências em determinadas situações e oportuni... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Currently, the application of solar thermal energy for water heating is a technical and economically viable solution allowing the reduction of electricity consumption in the residential, commercial and industrial sector. Given this, it is increasingly the domain methodologies that enable more necessary to quantify the useful thermal energy captured by solar collectors and determine their efficiency in the generation of hot water. As a way to contribute to this goal, this paper develops a comparative analysis of thermal energy harvesting in flat solar collector. From experimental and theoretical data, different models for processing the data were applied and compared. The methodology of the study was to monitor a residential solar heating system in real conditions of use and, from the data calculate and compare the uptake of useful thermal energy in solar collectors based on the energy balance of the First Law of Thermodynamics and by the Instantaneous Thermal Efficiency Method. The global solar radiation incident on the places of the solar collector plane was also monitored and therefore its value was compared to the theoretical model. Finally, the monthly demand for hot water thermal energy consumption of the house was also monitored and compared to the monthly energy harvesting. The application showed consistency between experimental and theoretical results in most cases, some inconveniences in certain situations and opportunities for improvements, in what is considered good design practice, as highlighted in the work / Mestre

Thesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2016. / South Africa has raised concerns regarding the development of renewable energy sources such as wind, hydro and solar energy. Integration of a combined photovoltaic and thermal system was considered to transform simultaneous energy into electricity and heat. This was done to challenge the low energy efficiency observed when the two solar energy conversion technologies are employed separately, in order to gain higher overall energy efficiency and ensure better utilization of the solar energy. Therefore, the notion of using a combined photovoltaic and thermal system was to optimize and to improve the overall PV panel efficiency by adding conversion to thermal energy for residential and commercial needs of hot water or space heating or space cooling using appropriate technology. The PV/T model constructed using water as fluid like the one used for the experimental work, presented a marginal increase in electrical efficiency but a considerable yield on the overall PV/T efficiency, because of the simultaneous operation by coupling a PV module with a thermal collectors.

Orientador: Teófilo Miguel de Souza / Coorientador: José Antonio Perrella Balestieri / Banca: José Feliciano Adami / Banca: Paulo Cesar Boggiani / Resumo: A disponibilidade de luz solar, transformada em energia, pode ser capturada em quase todo o mundo. Desde a década de 1990 o mercado da utilização de energia solar vem crescendo, porém informações sobre estudos de caso para a avaliação da inserção de aquecedores solares de água nos domicílios populares brasileiros ainda são escassas. O presente trabalho visa contribuir para reduzir essa carência e tem como objetivo avaliar a viabilidade técnica e econômica da inserção de aquecedores solares de água nas residências populares no município de Tremembé, localizado no Vale do Paraíba, estado de São Paulo, Brasil. O município de Tremembé possui uma área de 192 km² e conta com uma população de 42.027 habitantes, sendo um total de 10.632 domicílios. A avaliação foi efetuada numa amostra setorial do total de domicílios, através de um plano amostral aleatório estratificado, metodologia que permite conhecer melhor as características próprias de cada setor do município estudado. A pesquisa de campo foi efetuada com o método survey, com o total de 360 questionários, os quais foram aplicados a um representante de cada família. Imagens com as descrições e atributos dos setores censitários do IBGE foram tratadas no formato de extensão kmz. Foi necessária a construção de um cadastro no programa Excel para inserir os dados colhidos em campo e esses dados foram sobrepostos aos layers das imagens tratadas. O resultado desta pesquisa mostrou aceitação generalizada da população à possibilidade de instalações e utilização de sistemas de aquecimento solar de água, especialmente nas áreas rurais, principalmente por apresentar custo reduzido de energia elétrica no pico e aponta para a redução da demanda na rede elétrica. A pesquisa comprova que com a utilização de energia solar, o município pode economizar 31.680.000 kWh/ano, o que corresponde a R$ 9.504.000,00 /ano / Abstract: The availability of sunlight converted into energy can be captured throughout the world. Since the 1990s the market for the use of solar energy has been growing, but information on case studies to assess the inclusion of solar water heaters in the popular Brazilian households are still scarce. The present work aims at contributing to reduce this gap and aims to assess the technical and economic feasibility of integration of solar water heaters in low-income households in the municipality Tremembé, located in the Paraíba Valley, State of São Paulo, Brazil. Tremembé has an area of 192 km ² and has a population of 42,027 inhabitants, with 10,632 households. The evaluation has done on a sectorial sample of total households. Effected through a stratified aleatory sampling plan, as this methodology allows better understanding the characteristics of each sector of the municipality. The field research was conducted with the survey method, with 360 questionnaires, which have been applied to a representative of each family. Images with descriptions and attributes of the official census sectors of IBGE have been treated in the extension kmz format. It was necessary to build a register in Excel to insert the data collected in the field and these data were overlaid on the images Leyers treated. The result of this research showed widespread acceptance of the population the possibility of facilities and use of solar water heating systems, especially the rural areas, mainly by presenting reduced cost of electric power in peak and points to reduced demand in the power grid. The research proves that with the use of solar energy, the city may save 31, 68 million kWh/year, which corresponds to R$ 9,504,000.00/ year / Mestre

Orientador: Alcides Padilha / Banca: Enio Pedone Bandarra Filho / Banca: Celso Luiz da Silva / Resumo: No estudo de reaproveitamento de energia térmica, os refrigeradores domésticos dissipam calor para o meio ambiente, através do seu condensador, e esse calor pode ser reciclado, ou seja, recuperado através de escoamento de água, como fluido refrigerante escoando pelo condensador e armazenada em um reservatório. Para isto, construi-se um aparato experimental contendo um refrigerador doméstico, duplex com capacidade de 263 litros para o gabinete de refrigeração e 74 litros para o gabinete de congelamento. O refrigerador tem seu condensador acrescido por um trocador de calor tipo tubos concêntricos em contra corrente, cuja fruição é condensar o fluido refrigente utilizando água em circulação. Dessa forma, caso ocorra o carregamento térmico total do tanque de armazenagem, o calor será originalmente dissipado para o meio ambiente, através do condensador aletado. A água aquecida é então armazenada em um reservatório térmico via estratificação térmica. Assim calculou-se as vazões de água aquecida e fluido refrigerante, como também o coeficiente de desempenho do sistema acumulado. Os resultados mostraram que a vazão de água bem como o coeficiente de desempenho do sistema aumenta de acordo com o aumento da pressão hidrostática. Desta maneira, dos resultados obtidos pode-se concluir que a otimização do experimento se dá de forma eficaz e que, o reaproveitamento da água quente proveniente do condensador é perfeitamente possível, reduzindoo consumo de energia elétrica com aquecedores de água e ainda, minimizando a dissipação de calor para o meio ambiente, sem alterar o funcionamento do refrigerador / Abstract: In the study of recycling thermal energy it is know that domestic refrigerators dissipate heat to environment through the condenser. This heat can be recycled by a water flow, as a coolant in a modified condenser, and stored in a Domestic Hot Water Storage Tanks (DHWST). Thereby, an experimental apparatus was built containing one domestic refrigerator, each one with capacity of 263 liters in the cooling cabinet and 74 liters in the freezing cabinet. The refrigerators had the condenser increase by a type heat exchanger concentric tubes with a counter-current flow, which has the function of replace the original finned exchanger, condensing the coolant with water flow. Thus, in case the total thermal loading of the storage tank, the heat is dissipated to the original environment through the condenser finned. The heated water is then stored in a thermal reservoir via thermal stratification. In these conditions, the flow of heated water and refrigerant was calculated, as well as the coefficient of performance of the system. The results show that the water flow rate and the coefficient of performance of the system increases with the increase in hydrostatic pressure. According to these results, the experiment optimization is effective and it is totally possible to reuse the warm from modified condenser system, what could reduce the electric energy consumption in water beater and minimize the heat dissipation to environment, without modifying the refrigerator operation / Mestre