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Desempenho de sistemas de condicionamento de ar com utilização de energia solar em edifícios de escritórios.; Performance of solar air conditioning systems in office buildings.

Ara, Paulo José Schiavon
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 14/12/2010 PT
Relevância na Pesquisa
66.18%
A preocupação energética tem impulsionado a humanidade a buscar alternativas sustentáveis de energia. Neste contexto, os edifícios de escritórios têm um papel importante, em especial, devido ao elevado consumo de energia dos sistemas de condicionamento de ar. Para esses sistemas, a possibilidade de utilização de energia solar é uma alternativa tecnicamente possível e interessante de ser considerada, principalmente porque, quando a carga térmica do edifício é mais elevada, a radiação solar também é mais elevada. Dentre os sistemas de condicionamento de ar solar, o sistema térmico - que associa coletores solares térmicos com chiller de absorção - é o mais disseminado, na atualidade. Entretanto, dependendo do caso, outras tecnologias podem ser vantajosas. Uma opção, por exemplo, no caso de edifícios de escritórios, é o sistema elétrico - que associa painéis fotovoltaicos ao chiller convencional de compressão de vapor. Neste trabalho, para um edifício de escritórios de 20 pavimentos e 1000 m2 por pavimento, na cidade de São Paulo, no Brasil, duas alternativas de ar condicionado solar tiveram seus desempenhos energéticos analisados: o sistema térmico - com coletores solares térmicos somente na cobertura e o sistema elétrico - com painéis FV somente nas superfícies opacas das fachadas. Para isso...

Life cycle assessment of solar thermal systems

Fernandes, V.; Mateus, Ricardo; Bragança, L.; Silva, Sandra Monteiro; Almeida, Manuela Guedes de
Fonte: ITeCons Publicador: ITeCons
Tipo: Conferência ou Objeto de Conferência
Publicado em /12/2014 ENG
Relevância na Pesquisa
86.01%
The better understanding of cost-benefit, economic and environmental performances of solar thermal systems (STSs) is crucial for designers to be able to take a conscious and weighted decision about the installation of these systems. Therefore the goal of this research was to create a methodology for designers to support decision-making in the selection of the most adequate STS for a project and as result to contribute to a more sustainable built environment. This methodology allows the calculation of the potential environmental impacts, such as the global warming potential, acidification, eutrophication, ozone depletion, embodied energy, amongst others, together with the life-cycle costs resulting from the implementation of STSs in buildings. The system boundary includes the production of the various parts of the solar thermal system, such as the solar collector and the hot water tank, the assembly process, the maintenance stage, the auxiliary energy consumption and the end of life of this system. In the economic analysis, both initial and maintenance costs are considered together with the cost of the auxiliary energy. At the end, it is possible to quantify carbon, energy and cost payback periods. One practical application of the methodology will be carried out in the end of this work...

Avaliação de ciclo de vida de sistemas solares térmicos em edifícios; Life cycle assessment of solar hot water systems in buildings

Fernandes, Verónica Marisa Martins
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Trabalho de Conclusão de Curso
Publicado em //2014 POR
Relevância na Pesquisa
56.06%
Dissertação de mestrado integrado em Engenharia Civil; A presente dissertação aborda fundamentalmente conceitos de cariz ambiental e económico aplicados ao ciclo de vida de sistemas solares térmicos para águas quentes sanitárias. Com este trabalho pretende-se alertar os projetistas para a problemática atual das alterações climáticas, de forma a privilegiar o uso de energias renováveis, mais concretamente de energia solar. Para tal serão apresentados e discutidos conceitos e noções sobre a legislação e o mercado dos sistemas solares térmicos, assim como os principais componentes que constituem esses sistemas. No fim do estudo apresenta-se uma metodologia de avaliação de ciclo de vida de sistemas solares térmicos com base numa análise LCA e LCC, que desencadeou o desenvolvimento de um programa informático que tem como objetivo a integração mais rápida do sistema solar térmico na construção e, portanto, promover a sua sustentabilidade. O programa permite o cálculo dos potenciais impactes ambientais tais como aquecimento global, acidificação, eutrofização, destruição da camada de ozono, energia incorporada, etc., decorrentes do ciclo de vida do sistema solar térmico, os impactes desse sistema ao longo do tempo de vida do edifício e a sua viabilidade económica. Posteriormente...

Execução de um projecto solar térmico para uma instalação de A.Q.S. da Escola Básica Guilherme Stephens

Silva, Miguel Martins da
Fonte: Instituto Politécnico de Lisboa Publicador: Instituto Politécnico de Lisboa
Tipo: Dissertação de Mestrado
Publicado em /12/2012 POR
Relevância na Pesquisa
66.06%
O presente documento tem como principal objectivo efectuar o projecto de dimensionamento de um sistema de águas quentes sanitárias para uma escola. Numa primeira fase foi elaborado uma pesquisa sobre o contexto energético, a nível mundial, europeu e nacional, bem como o seu contexto jurídico a nível europeu e nacional, e uma explicação superficial sobre os fundamentos da energia solar, onde se foca a importância da radiação solar e os vários tipos de sistemas solares térmicos, bem como os seus constituintes. Segue-se a abordagem ao caso de estudo onde foram efectuados inicialmente inquéritos como forma de determinar os consumos de água quente utilizada nessa escola. Continuou-se o estudo efectuando-se a variação de duas características do sistema solar: o tamanho dos depósitos e o tipo de colectores solares a aplicar. Após as simulações efectuadas para a determinação das soluções a aplicar ao sistemasolar e apresentadas ao longo do presente documento, foram efectuadas análises económicas como forma de se verificar a viabilidade do sistema a aplicar. Por último foram elaboradas conclusões sobre o sistema a aplicar e apresentados alguns cenários financeiros do mesmo.; The present document has as main objective to make the draft design of a hot water system for a school. Initially a research was developed at energy context...

Estudo comparativo de sistemas em aquecimento

Castro, Inês Marques Costa Borges de
Fonte: Instituto Politécnico de Lisboa Publicador: Instituto Politécnico de Lisboa
Tipo: Dissertação de Mestrado
Publicado em /12/2013 POR
Relevância na Pesquisa
56.1%
O presente estudo pretende avaliar o desempenho energético e rentabilidade do uso de equipamento de climatização para o aquecimento ambiente de uma casa sénior, através de sistemas tradicionais de produção de água aquecida, como a caldeira e a tradicional bomba de calor, e um sistema apoiado num equipamento de produção solar térmico. Perante uma determinada arquitectura, foram calculados os caudais de ar novo, de forma a garantir a qualidade do ar interior, cumprindo os requisitos da actual legislação - RSECE. Com recurso ao programa de cálculo e simulação HAP – Hourly Analysis Program – foram determinadas as necessidades térmicas para conforto de cada espaço em análise, e traçou-se o perfil de consumo energético anual do edifício. Com os valores obtidos das cargas térmicas a colmatar em cada hora do mês, ao longo de um ano, e com o auxílio de um programa de análise de desempenho de sistemas solares térmicos – SolTerm – foi optimizado um sistema solar para o caso de estudo. Analisando o rendimento e desempenho de cada tipo de equipamento e sistema, bem como os custos de instalação e de exploração, foram determinadas as poupanças energéticas na factura e o período de retorno de investimento...

Trnsys simulation results of an existing monitored small scale CHCP system and mathematical model adaptations of the air-cooled ammonia chiller and CHP prototypes

Mendes, J. Farinha; Coelho, Ricardo; Cardoso, João P.; Costa, João P.; Fernández, David; Silva, António, R.; Morgado, Miguel; Adão, Pedro
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Publicado em //2010 ENG
Relevância na Pesquisa
65.89%
This work is a TRNSYS simulation of solar thermal system working together with an existing small sized CHCP (Combinet Heat Cooling and Power) demonstration project, included in the workpackage 5 (simulation) of the PolySMART project. The first objective of this work is to fine tune simulation parameters of the simulation Units (or Types), based on monitoring data collected during the first semester of 2010. The second objective is to further develop the mathematical models of type 107 (Hot Water-Fired Single-Effect Absorption Chiller) and type 120 (HYDROGEMS: Diesel Engine Generator System (DEGS) - Version 1.1). This will tackle the remaining differences between the real and simulated systems. These differences are due to the fact that both the CHP and the Ammonia-Water Air Cooled Chiller are prototypes. The third objective is to simulate the performance of different thermal collectors, some of which are also prototypes, and choose a proper solution for future experiments. The forth objective is to compare local weather data sets, collected on site since 2007, with proven standard data sets. Further work may be developed regarding the fan coils used to carry in/out heat.

On the Best Practice Implementation of Solar Thermal Obligations. The ProSTO EU Project and the Portuguese experience

Prates, Manuel João Lopes; Mendes, J. Farinha; Carvalho, M. J.
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Publicado em /11/2009 ENG
Relevância na Pesquisa
65.97%
Based on the work that it is running within the ProSTO EU project (http://www.solarordinances.eu/), this paper presents a tentative approach to the best way for a successful implementation of a solar thermal obligation (STO) in a community. The EU framework, and base line assessment – including success factors and performance indicators were presented by the ProSTO coordinator elsewhere [1]. The Portuguese case was presented elsewhere too [2]. Here, all the complete set of measures that must be taken to succeed, will be presented. The experience shows that it is necessary to get an integrated “policy package” in the way of “zero building emissions”, around the kernel key point of clear requirements, aiming energy savings, namely for energy demand limitation, and energy efficiency of thermal installations. A parent kernel key point of this “policy package” is quality: certification of thermal solar system and components – solar collectors, factory made systems, and custom built systems; planner, designer and installer certification; technical impositions in the regulations (supported by a very consistent manual of actual good practices for solar thermal applications, with a flexible method to follow new developments); guarantee impositions (maintenance contract). All relevant documents of these quality items must be integrated in the Building Use Manual for easy management. Another kernel key point...

Solar thermal collector yield: experimental validation of calculations based on steady-state and quasi-dynamic test methodologies

Horta, Pedro; Carvalho, M. J.; Fischer, S.
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Publicado em 07/10/2008 ENG
Relevância na Pesquisa
65.95%
The characterization of collector efficiency is the fundamental tool for long term calculation of collector yield. It is, thus, one of the most important inputs in software tools aiming the design of solar thermal systems. Presently two test methodologies are available for characterization of the efficiency of glazed collectors: i) steady state test and ii) quasi-dynamic test, methodologies based in different model approaches to a solar collector, providing different collector efficiency curve parameters and, consequently, imposing different power calculation algorithms. Moreover, Horta et al (2008) demonstrated that the use of the collector efficiency curve derived from steady state test method is not enough for a thorough characterization of the long term performance of a collector. The present work takes into account the introduction of the above referred test methodologies in the European Test Standard for Solar Thermal Collectors, and aims at clarifying how each test results should be used in long term thermal performance calculations. The paper presents a synthesis of the different efficiency parameters provided by each test methodology and corresponding algorithms, applicable in the calculation of delivered power. Application of these algorithms to two days of measured data allows for a comparison of the results obtained with these different methodologies. For validation purposes...

European round robin test on solar collectors and solar thermal systems

Fischer, S.; Carvalho, M. J.; Weißmüller, C.
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Publicado em //2011 ENG
Relevância na Pesquisa
76.12%
Within the European project QAiST (Quality Assurance in Solar Thermal Heating and Cooling Technology)a Round Robin test on solar collectors and solar thermal systems is carried out in the years 2010 and 2011. For two different collector types, one flat plate collector and one evacuated tubular collector with CPC reflector, thermal performance tests according to EN 12975-2 (EN 12975, 2006) are carried out by 12 different test institutes throughout Europe. The two different solar thermal systems, one thermosiphon system and one system with forced circulation are subject to a thermal performance test according to EN 12976-2 (EN 12976, 2006) and are tested by 9 different test institutes.In order to finish the Round Robin test within two years despite of the high number of participants, the following procedure was applied: Each participant received in the year 2010 samples of the two different collector types and of the two solar thermal system types respectively. After testing, the samples have been sent to the next test institute to be tested within the year 2011. Thus all institutes are testing identical collectors and system types taken out of the same production batch, however each unique collector or system is only tested by two institutes. For the first time Round Robin tests on solar thermal products are evaluated by an independent institute (Institut für Eignungsprüfung) using the acknowledged procedures for the evaluation of proficiency tests.This paper presents some of the midterm results of the Round Robin test in an anonymous and standardised way.

Components of solar thermal systems

Mendes, J. Farinha; Carvalho, M. J.; Schossig, Peter
Fonte: Springer-Verlag/Wien Publicador: Springer-Verlag/Wien
Tipo: Parte de Livro
Publicado em //2013 ENG
Relevância na Pesquisa
76.02%
The heat production sub-system is the part of the overall system which provides heat to a thermally driven air-conditioning system. With regards to the solar-driven equipment, the solar collector is the main component of the sub-system. A brief review on the present state-of-the-art with respect to performance characteristics and available certification schemes of solar collectors is given in the following chapter. Besides the solar collector field, the storage unit and the back-up heat source unit are also important components. An overview of these items and the identification of other relevant components of the solar thermal system are given in the following sections.

Evaluation of solar aided biomass power generation systems with parabolic trough field

Hou, H.; Yang, Y.; Hu, E.; Song, J.; Dong, C.; Mao, J.
Fonte: Zhongguo Kexue Zazhishe Publicador: Zhongguo Kexue Zazhishe
Tipo: Artigo de Revista Científica
Publicado em //2011 EN
Relevância na Pesquisa
56.05%
Solar and biomass are both renewable energy resources. Using biomass as fuel is becoming more and more attractive after governments increase the tariff for the electricity from the renewable sources. However the costs of power from a biomass power generation plant depend greatly on the availability and quality of the biomass resource. The commercialization of solar alone thermal power generation is hindered by its high initial investment and low thermal efficiency. In this paper, a concept of integrating solar into a biomass power generation system is put forward. In the system the oil heated by a parabolic trough solar field is used to replace the extraction steam to preheat the feed water (entering a biomass boiler) and the previous extraction steam thus saved can continue to do work in the lower stages of turbine. The performance of the hybrid system with different replacements is analyzed and compared through two typical solar aided biomass generating units. The results show that the integration not only reduces the consumption of biomass fuel (at the same generation capacity) but is also proved to be an efficient way to convert solar thermal energy into power. The results also show that with the same solar aperture area, the higher the grade of the replaced extraction steam...

Application of chemical looping combustion for solar thermal energy storage

Jafarian, S.; Arjomandi, M.; Nathan, G.; Nasehi, S.
Fonte: The Combustion Institute; Australia Publicador: The Combustion Institute; Australia
Tipo: Conference paper
Publicado em //2011 EN
Relevância na Pesquisa
56.1%
In this paper a solar hybrid chemical looping combustion (CLC) system for solar thermal energy storage (TES) is proposed. For those combinations of fuels and metal oxides in CLC systems with an endothermic reaction, there is a potential to utilize solar thermal energy to drive the CLC reactions and so to allow the solar thermal energy to be stored as a reduced metal oxide. The application of oxygen carrier particles for solar thermal energy storage is also possible. A novel solar hybrid system is proposed and assessed, in generation cycles to enable base load generation from solar thermal energy. For this purpose three reservoirs are added to a CLC system to store the oxygen carrier particles and a cavity solar reactor is used as the fuel reactor. The ASPEN PLUS software is used to simulate the hybrid process. Basic validation of the model is performed using independent simulation result reported previously and the model is then used to calculate operating temperature, solar efficiency and solar fraction of the system. The results identify potential benefits from the solar hybridization of a CLC system.; S.M. Jafarian, M. Arjomandi, G. Nathan and S.M. Nasehi

A hybrid solar and chemical looping combustion system for solar thermal energy storage

Jafarian, S.; Arjomandi, M.; Nathan, G.
Fonte: Elsevier Sci Ltd Publicador: Elsevier Sci Ltd
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
56.11%
A novel hybrid of a solar thermal energy and a chemical looping combustion (CLC) system is proposed here, which employs the oxygen carrier particles in a CLC system to provide diurnal thermal energy storage for concentrated solar thermal energy. In taking advantage of the chemical and sensible energy storage systems that are an inherent part of a CLC system, this hybrid offers potential to achieve cost effective, base load power generation for solar energy. In the proposed system, three reservoirs have been added to a conventional CLC system to allow storage of the oxygen carrier particles, while a cavity solar receiver has been chosen for the fuel reactor. The performance of the system is evaluated using ASPEN PLUS software, with the model being validated using independent simulation result reported previously. Operating temperature, solar efficiency, solar fraction, exergy efficiency and the fraction of the solar thermal energy stored for a based load power generation application are reported.; Mehdi Jafarian , Maziar Arjomandi, Graham J. Nathan

Assessment of the use of solar thermal collectors for desalination

Horta, Pedro; Zaragoza, G.; Alarcon-Padilla, D.C.
Fonte: Taylor & Francis Publicador: Taylor & Francis
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.01%
The use of renewable energy in desalination is the only sustainable way to decrease the water deficit without aggravating the energy crisis. Solar desalination is usually presented as the most optimal solution for sustainable desalination since the water needs are usually larger in places with high solar radiation. Considering the potential use of desalination as means of producing water in small isolated communities, the focus of this study lies on the use of solar energy in thermal desalination systems of small–medium capacity and low maintenance requirements. Based on typical values for the thermal energy requirements of such systems and on characteristic performance parameters of commercially available low-temperature solar thermal technologies, different system layouts are assessed and optimal system dimensioning is studied, for different locations, in terms of estimated water production costs.

Field Evaluation and Anaysis of a Liquid Desiccant Air Handling System

Jones, Benjamin Marcus
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 10136183 bytes; application/pdf
EN; EN
Relevância na Pesquisa
56.06%
A thermal liquid desiccant air handling machine was procured, installed, and field tested. The goal of the present investigation is to evaluate the field performance of the machine and characterize its operation for the temperature range of a solar thermal array. The system studied includes a natural gas boiler supplying the heat, and a cooling tower for heat rejection. System performance was evaluated for the 50 to 90 C temperature range, the operating range of solar thermal collectors. Cooling power varied between 4.3 kW and 22.8 kW for this range of temperature, with a latent heat ratio between 1.1 and 1.9, confirming that the unit is significantly dehumidifying the process air stream. Electrical COP varied between 0.58 and 4.48. Performance data indicates higher temperature solar collectors such as evacuated tube or double glazed flat plat collectors would be optimum in a solar cooling application with this system. Empirical correlations for the regenerator and conditioner components were obtained using a multivariate linear regression model. 5 empirical relations were derived and can be used to characterize the thermal dehumidification concept. These relations and methods will be used in future work to simulate and optimize a solar thermal driven dehumidification system for dedicated outdoor air systems.; Thesis (Master...

Preliminary Investigation into Solar Thermal Combi-system Performance

Lee, Elizabeth
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
76.19%
Solar thermal combi-systems use solar energy to provide thermal energy for space heating and domestic hot water. These systems come in many different designs and configurations, and their performance is dependent on many different factors such as location, solar collector type and orientation, and thermal storage size. In this study, two different combi-system configurations (a basic combi-system, and a single-tank combi-system) as well a stand-alone solar space heating system and a stand-alone solar domestic hot water system were investigated using TRNSYS models and simulations, and the thermal performances were compared using different combinations of solar collector and heat exchanger types, different locations, and a sensitivity analysis was performed using the basic solar combi-system. Using Toronto as the reference location, the performance of the solar stand-alone and combi-systems were compared using combinations of solar collector types (glazed vs. vacuum tube) and heat exchanger types (fixed effectiveness vs. natural convection). Each system combination was optimized for collector flow rate and tilt angle, and all systems were given the same solar collector area, thermal storage volume, and load profiles. This analysis revealed that the glazed type solar collector performed best when the heating load was continuous throughout the year...

Eficiência energética, aplicação em edifícios de serviços: o caso do hospital do ICUF

Silva, Nélson Ferreira da
Fonte: Instituto Politécnico do Porto. Instituto Superior de Engenharia do Porto Publicador: Instituto Politécnico do Porto. Instituto Superior de Engenharia do Porto
Tipo: Dissertação de Mestrado
Publicado em //2012 POR
Relevância na Pesquisa
66.06%
Mestrado em Engenharia Electrotécnica – Sistemas Eléctricos de Energia; A eficiência energética é um assunto atual de todos os países devido à crise do petróleo em 1973. Portugal é um dos países que devido às alterações climatéricas iniciou uma procura incessante por energias alternativas, registando assim resultados positivos. No entanto, não se deve apenas utilizar as energias alternativas mas sim realizar um uso mais eficiente dessas. Como Portugal apresenta um clima mediterrânico constata-se uma elevada quantidade de horas de exposição solar. Assim, a utilização desta energia, nomeadamente através de um sistema solar térmico, reúne as condições favoráveis na obtenção de uma diminuição dos custos na fatura energética. Salienta-se que esta fatura tem um elevado peso nos gastos de um edifício de habitação ou de serviços. Outra forma de diminuir os gastos é através de um sistema de cogeração. Esta consiste na produção combinada de energia térmica e elétrica num mesmo equipamento, destinando-se ambas ao consumo da própria empresa ou de terceiros. O propósito desta dissertação assenta na avaliação de desempenho energético do edifício Instituto CUF em Matosinhos ao nível da qualidade térmica dos edifícios e dos seus sistemas energéticos. Também tem como objetivo a recolha de informação que permita a determinação de economias de energia numa ótica de Eficiência Energética e de Utilização Racional de Energia...

Evaluación de la rentabilidad en un sistema solar térmico : caso de estudio en un edificio residencial de la Comuna de Vitacura, Santiago

Schnaidt Hagedorn, Mauricio
Fonte: Universidad de Chile Publicador: Universidad de Chile
Tipo: Tesis
ES
Relevância na Pesquisa
56.1%
Memoria para optar al título de Ingeniero en Recursos Naturales Renovables; El consumo de energía en el mundo se incrementará en un 57% entre 2004 y 2030. Para enfrentar este crecimiento Chile tiene como objetivos centrales en materia energética diversificar la matriz, establecer precios competitivos de la energía y que ésta sea sustentable con el medio ambiente. En este escenario, las ERNC permitirían cumplir tales objetivos en una gran medida. Dentro de las ERNC, la energía solar térmica ha mostrado un crecimiento a nivel mundial en los últimos años, incluido en Chile, que presenta altos niveles de radiación solar para su desarrollo. Con el propósito de exponer las ventajas de la energía solar térmica, se propuso evaluar la rentabilidad de un sistema solar térmico para producir agua caliente sanitaria en un edificio residencial, ubicado en la Región Metropolitana, a través de una evaluación técnicoeconómica. El edificio utilizado como caso de estudio presenta una demanda media diaria anual de 15.839 litros de agua caliente sanitaria y utiliza calderas a gas natural para cubrirla. A través de la evaluación técnica se determinó que la superficie óptima de colectores solares, para satisfacer el 62...

Solar Thermal Energy Systems in Australia

Lovegrove, Keith; Dennis, Michael
Fonte: Taylor & Francis Group Publicador: Taylor & Francis Group
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
65.99%
Australia has developed world leading solar thermal technologies, with only very low national market penetration. Domestic solar water heating is the most common solar thermal instrument, with around 5% of homes using it and most of these systems are conv

System and component modelling of a low temperature solar thermal energy conversion cycle

Situmbeko,Shadreck M; Inambao,Freddie L
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2013 EN
Relevância na Pesquisa
66.06%
Solar thermal energy (STE) technology refers to the conversion of solar energy to readily usable energy forms. The most important component of a STE technology is the collectors; these absorb the shorter wavelength solar energy (400-700nm) and convert it into usable, longer wavelength (about 10 times as long) heat energy. Depending on the quality (temperature and intensity) of the resulting thermal energy, further conversions to other energy forms such as electrical power may follow. Currently some high temperature STE technologies for electricity production have attained technical maturity; technologies such as parabolic dish (commercially available), parabolic trough and power tower are only hindered by unfavourable market factors including high maintenance and operating costs. Low temperature STEs have so far been restricted to water and space heating; however, owing to their lower running costs and almost maintenance free operation, although operating at lower efficiencies, may hold a key to future wider usage of solar energy. Low temperature STE conversion technology typically uses flat plate and low concentrating collectors such as parabolic troughs to harness solar energy for conversion to mechanical and/or electrical energy. These collector systems are relatively cheaper...