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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Modelling and performance analysis of a sub-dew point chilled beam in mixed mode buildings

Wheatley, A. January 1999 (has links)
Prompted by the energy crisis in the 1970's, European level fiscal and financial measures encourage energy efficient building design. "Mixed mode" strategies can be employed in buildings with moderate thermal loads, this approach can reduce building energy usage, and by inference, reduce C02 emissions. A mixed mode approach might employ chilled surfaces with displacement ventilation. This thesis investigates the performance and integration of one form of chilled surface design, (a sub-dew point chilled beam), within mixed mode strategies. Sub-dew point chilled beams have a surface temperature that is at or below the zone saturation temperature, this increases the cooling capacity of the chilled beam and consequently produces a latent heat transfer addition due to condensation mass transfer. This thesis describes the sensible and latent modelling approach which models the zone, sub-dew point chilled beam and mixed mode strategy thermal plant response to external disturbances. The thesis describes the use of an Enclosure Comfort Performance Indicator that acts as the objective function for the optimization of the mixed mode strategies with and without the integration of the sub-dew point chilled beam. The implementation of the Complex method for finding the operational optimums of the mixed mode strategy is described, and its effectiveness at finding the optimum solution evaluated. Normalised energy, cost and comfort performance indicators are used to assess the overall performance and integration of the sub-dew point chilled beam for different mixed mode strategies, for the ambient test conditions and for different thermal weights of building construction.
2

Sistemas baseados em conhecimento para aplicação de eficiência energética e conservação de energia para plantas industriais /

Buccieri, Gilberto Paschoal. January 2018 (has links)
Orientador: José Alexandre Matelli / coorientador: José Antonio Perrella Balestieri / Banca: Rubens Alves Dias / Banca: Paloma Maria Silva Rocha Rizol / Banca: Jonny Carlos da Silva / Banca: Elisangela Martins Leal / Resumo: Este trabalho apresenta o desenvolvimento de um protótipo de sistema especialista (SE) dotado de um módulo de geração de explicação (MGE) para diagnóstico preliminar de eficiência energética em plantas industriais, considerando as características fundamentais de operação e manutenção dessas plantas. Embora a capacidade de explicar processos de raciocínio distinga o SE de outros sistemas de apoio à decisão, disponibilizar um MGE ajuda a promover uma análise crítica das decisões tomadas pelo SE. Em adição, o MGE é muito útil também na validação da base de conhecimento, permitindo detectar erros semânticos do sistema e monitorar detalhes do processo de inferência, o que pode levar a uma redução de tempo de desenvolvimento e maior aceitação do sistema, aumentando dessa forma sua confiabilidade e principalmente, sua credibilidade. A base de conhecimento do sistema foi construída a partir da experiência de especialistas multidisciplinares da área de eficiência energética industrial, o que é certamente um recurso valioso em um contexto de gestão do conhecimento (GC) organizacional. A GC torna o conhecimento humano especializado em valor duradouro, criando uma memória corporativa por meio de ações de compartilhamento e retenção, o que pode contribuir para a melhoria contínua dos processos, criação de valor e manutenção de vantagens competitivas. Para demonstrar as possibilidades de melhoria de eficiência energética, os principais sistemas de utilidades de uma planta industrial são ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work presents the development of an expert system prototype (ES) with an explanation facility module (EFM) for preliminary diagnosis of energy efficiency guidelines in industrial plants, considering the fundamental characteristics of operation and maintenance of these plants. Although the ability to explain its own reasoning distinguishes ES from other decision support systems, providing an EFM contributes to promote a critical analysis of the decisions taken by the ES. In addition, the EFM is also very useful in validating the knowledge base, because it facilitates the detection of semantic errors and allows a better monitoring of the inference process. Because of that, the EFM can reduce the development time and contribute to a broader acceptance of the system, which positively impacts its reliability and credibility. The knowledge base of the system was built on the experience of multidisciplinary experts in the field of industrial energy efficiency that is certainly a valuable resource in an organizational knowledge management (KM) context. The KM becomes the human knowledge in permanent value by creating a corporate memory through sharing and retention actions that may contribute to continuous improvement of processes, value creation and maintaining competitive advantage. In order to properly demonstrate the possibilities of energy efficiency improvement, the main utility systems of an industrial plant are analyzed individually. To do so, such systems are classified... (Complete abstract click electronic access below) / Doutor
3

Ekonomická analýza pasivních domů / Economic analysis of passive houses

Řezníčková, Tereza January 2016 (has links)
The master thesis deals with passive houses and their profitability's economic analysis. The thesis focuses on both new buildings and renovations, which have the greatest potential for energy savings in the building's sector. The cost-effectiveness of proposed measures is evaluated using the example of reconstruction of an existing house with passive and low-energy standard. Low-energy option of reconstruction is more profitable from an investor's perspective than the passive one. At 4% annual growth in energy prices, both options become comparable. The result of the calculation is not generally applicable. The profitability always depends on a specific building and various measures. Besides the cost-effectiveness, the investor's decision about an investment is also influenced by an increasing level of living comfort, subsidies and environmental protection.
4

Energy efficient buildings in Qingdao, China

Tengteng, Sun January 2011 (has links)
At present, an important task for Chinese governments at all levels is to save energy and reduce pollutant emissions. The task of buildings energy efficiency accounts for 21% in the 12th Five Year Plan which from 2011 to 2015. With the development of social economy,the energy shortage is serious day by day.The energy-conservation of buildings is a high relevant issue in China.There are a large capacity and a wide range of existing buildings in Qingdao among which the overwhelming majority is the non-energy-efficient buildings and the operate energy consumption are enormous.At Present, according to the related statistic,the energy efficient building area only accounts for 3% to 5% of the total building area newly increased in our country every year, while in such existing buildings in Qingdao ,most of them are highly energy-consuming, the energy consumption in buildings is about 100-350 kWh for each floor area of the whole year,which is 2 to 3 times of the energy consumption of the same area of energy efficient buildings.So we can say that whether could we promote the effective use of resources and energy in buildings is very important,which will finally determine whether could we and take the road to sustainable development. In respect of the application of the complicated systematic scientific conclusions,the thesis carries out the analysis of geographic and climate characteristics in Qingdao area and the research of current energy consumption. Based on the quantitative model analysis of environmental and economic benefits of implementation of energy efficient buildings in Qingdao in scenario k, promotion and implementation of energy efficient buildings can substantially reduce the current high environmental cost associated with energy consumption for heating and cooling in buildings in Qingdao. Emission including carbon dioxides, sulfur oxide, nitrogen oxides and ash can be reduced, it means that under the scenario k energy efficient buildings has an idea performance on reducing pollutant gas. At the same time, companied by the great environmental benefits, there are also substantial economic benefits. Barriers to energy efficiency in buildings in Qingdao, including political, economic, social and technological barriers are discussed in this thesis. According to the investigation and analysis about the present situation and factors affecting the implementation of energy efficient buildings in Qingdao, this thesis put forward recommendations from the aspects of environment, politics, economy, society and technology to improving energy efficient buildings in Qingdao.
5

Green Buildings : Exploring performance and thresholds

Bonde, Magnus January 2016 (has links)
The overall aim of this research project is to study green/energy-efficient real estate from an economic perspective. The thesis summarizes the results from five different studies with a connection to green/energy-efficient real estate.The aim of the first paper (paper A) is to study how tenants perceive the indoor environment in green-rated premises, and to compare these results with tenants’ perception of a conventional building’s indoor environment. The main result is that the tenants in the green-rated building are more satisfied with the indoor environment than the tenants in the conventional building.Papers B and C assess whether energy efficiency has an impact on buildings’ income and market values using Swedish real-estate data. The key result is that although there is a small impact on building-related income, this does not seem to translate into a higher market value.The last two papers included in this thesis study hindrances to a more energy-efficient building sector. In paper D, two office buildings are used as baseline cases to provide insights into the difficulties that can arise when trying to upgrade a building to make it more energy efficient. The results indicate that changing existing leases is a prohibitive process and that it is often difficult to evaluate the final impact of an energy upgrade. The last paper focuses on why it may be rational to postpone green refurbishments even if they are profitable. The main result is that it may be rational to postpone such refurbishments. However, by introducing different financial penalties and/or subsidies, these investments could be triggered today.To sum up, the results indicate that green buildings are preferred by tenants, but that there still appear to be economic barriers to a greener building sector. / Det övergripande syftet med denna avhandling är att studera grön/energieffektiva byggnader ur ett ekonomiskt perspektiv. Avhandlingen består av en kappa och fem separata studier, vilka belyser tre olika forskningsfrågor. Syftet med den första studien är att studera hur hyresgäster upplever inomhusmiljön i gröna byggnader. I studien jämförs inomhusmiljön i en grön byggnad med inomhusmiljön i en likvärdig konventionell byggnad. Resultatet visar, på det stora hela, att hyresgästerna är mer nöjda med inomhusmiljön i den gröna byggnaden. De nästföljande studierna, B respektive C, undersöker om byggnadens energiprestanda har någon inverkan på dess hyra respektive marknadsvärde. Resultaten visar på en liten signifikant hyrespåverkan, dock verkar denna inte ha någon effekt på byggnadernas marknadsvärdebedömningar. Skälet till detta kan vara att hyrespremien anses för liten för att ha någon signifikant inverkan på byggnadens marknadsvärde, alternativt att fastighetsvärderare inte beaktar energiprestanda när en fastighet värderas. De två sista studierna studerar varför vissa, tillsynes lönsamma, energiinvesteringar inte genomförs. Resultaten från studie D visar på svårigheterna med att ingå ett samarbetsavtal (för att eliminera felaktiga incitament) mellan hyresgäst och hyresvärd. Sådana avtal tar lång tid att förhandla fram och det uppkommer ofta svårigheter med att utvärdera de tänkta energiinvesteringarnas ekonomiska utfall. Studie E utgår ifrån en realoptionsmodell, vilken används för att utvärdera när ”gröna” renoveringar bör genomföras i en befintlig byggnad. Studien visar att det kan vara rationellt att vänta trots att investeringen idag är lönsam. Vidare visar resultaten att det är möjligt att via byggsubventioner/finansiella ”straff” påverka aktörer att tidigarelägga energieffektiviseringsåtgärder.  Dock är det viktigt att dessa utformas korrekt så att det inte skapar några snedvridna incitament. Övergripande visar resultaten att gröna byggnader är att föredra ur ett brukarperspektiv men att det fortfarande finns ekonomiska hinder för en mer hållbar byggsektor. Nyckelord: gröna byggnader, energieffektiva byggnader, EPC, inomhusmiljö, Realoptioner, fastighetsekonomi. / <p>QC 20160407</p>
6

Integration of Phase Change Materials in Commercial Buildings for Thermal Regulation and Energy Efficiency

Malekzadeh, Fatemeh January 2015 (has links)
One of prospective procedures of absorbing thermal energy and releasing it during the required time is the application of phase change materials known as PCMs in building envelopes. High thermal energy storage (TES) materials has been a technology that effects the energy efficiency of a building by contributing in using onsite resources and reducing cooling or heating loads. Currently, many TES systems are emerging and contributing in building assemblies, however using an appropriate type of TES in a specific building and climate requires an in-depth knowledge of their properties. This research aims to provide a thorough review of a broad range of thermal energy storage technologies including their potential application in buildings. Subsequently, a comparative study and simulation between a basecase and an optimized model by PCM is thoroughly considered to understand the effect of high thermal storage building's shell on energy efficiency and indoor thermal comfort. Specifically this study proposes that the incorporation of PCM into glazing system as a high thermal capacity system will improve windows thermal performance and thermal capacity to varying climatic conditions. The generated results by eQUEST energy modeling software demonstrates approximately 25% reduction in cooling loads during the summer and 10% reduction in heating loads during the winter for optimized office building by PCM in hot arid climate of Arizona. Besides, using PCM in glazing system will reduce heat gain through the windows by conduction phenomenon. The hourly results indicates the effect of PCM as a thermal energy storage system in building envelopes for building's energy efficiency and thermal regulation. However, several problems need to be tackled before LHTES can reliably and practically be applied. We conclude with some suggestions for future work.
7

Lågenergihus : Att bygga energisnålt

Karlsson, Camilla January 2010 (has links)
<p>A large proportion of the energy consumption is in the building industry and a large part goes to heating our homes and premises. In the developing countries' development now threatens the large consumption of energy in our earth's climate. It is in the West world that we must be good role models in terms of energy efficiency. One solution to reduce energy consumption for heating of buildings may be to continue to build low energy houses and passive houses, but it is also about rebuilding the buildings that currently have high energy consumption such as the old Million program Houses. These buildings will be standing many years and their energy consumption will not diminish over time by itself and energy prices will certainly not diminish in the future. This report will touch on the subject mainly new construction, how to build an energy efficient building, but a smaller portion will touch on the subject rebuilding, particularly the solutions that can fit into economic terms.</p><p><strong> </strong></p><p>Calculations have been done to link the concepts of U<sub>mean</sub> of a building and its energy consumption. This was done by calculations using an Excel document created in connection with this thesis.</p><p> </p><p>The buildings and architectural solutions addressed in this report will focus on apartment buildings where the partner of this thesis is Eskilstuna Municipal Building. Eskilstuna Municipality Property manages buildings and premises to Eskilstuna Municipality, but also owns their own house with rental apartments.<strong></strong></p>
8

Lågenergihus : Att bygga energisnålt

Karlsson, Camilla January 2010 (has links)
A large proportion of the energy consumption is in the building industry and a large part goes to heating our homes and premises. In the developing countries' development now threatens the large consumption of energy in our earth's climate. It is in the West world that we must be good role models in terms of energy efficiency. One solution to reduce energy consumption for heating of buildings may be to continue to build low energy houses and passive houses, but it is also about rebuilding the buildings that currently have high energy consumption such as the old Million program Houses. These buildings will be standing many years and their energy consumption will not diminish over time by itself and energy prices will certainly not diminish in the future. This report will touch on the subject mainly new construction, how to build an energy efficient building, but a smaller portion will touch on the subject rebuilding, particularly the solutions that can fit into economic terms.   Calculations have been done to link the concepts of Umean of a building and its energy consumption. This was done by calculations using an Excel document created in connection with this thesis.   The buildings and architectural solutions addressed in this report will focus on apartment buildings where the partner of this thesis is Eskilstuna Municipal Building. Eskilstuna Municipality Property manages buildings and premises to Eskilstuna Municipality, but also owns their own house with rental apartments.
9

Conservação de energia em edificios comerciais atraves da implementação de dispositivos de automação / Conservation of energy in commercial buildngs through the implementation of automation devices

Gomazako, Marcone Susumo 23 October 2007 (has links)
Orientador: Carlos Alberto Mariotoni / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-09T15:15:44Z (GMT). No. of bitstreams: 1 Gomazako_MarconeSusumo_D.pdf: 5293277 bytes, checksum: 54ecece1926586b33b8eb4664a564549 (MD5) Previous issue date: 2007 / Resumo: Este trabalho vem apresentar um panorama do sistema elétrico geralmente encontrado em construções comerciais de grande porte, com cerca de trinta anos de funcionamento, que operam de forma pouco eficiente para os parâmetros atuais, principalmente no seu sistema de ar condicionado central. Nessa construção (estudo), seu sistema de condicionamento ambiental representa um acréscimo na demanda energética de cerca de 60%, passando de 450.000 kWh/mês para 750.000 kWh/mês, e a troca desses equipamentos por mais modernos e eficientes, significaria grandes investimentos, tornando-se inviável no curto prazo. Com isso, elaborou-se um protótipo contendo dispositivos de automação, que podem ser incorporados ao sistema existente, sem grandes dificuldades, e minimizando os custos operacionais com o sistema. Esses dispositivos permitem um monitoramento mais eficiente, sem a necessidade desses investimentos, como a substituição de grandes equipamentos (compressores, chillers, etc.) que fazem parte do sistema de ar condicionado central. Esse protótipo permitiu demonstrar que com a aplicação desses dispositivos incorporados nesses sistemas, podem gerar uma economia de cerca de 20% no consumo de energia elétrica, que representa uma economia bastante significativa de 60.000 kWh/mês (neste caso) quando operado o sistema de ar condicionado, além de aliviar os recursos humanos disponibilizados para esse tipo de monitoramento / Abstract: This work comes to present a panorama of the electric system found usually in commercial constructions of great load, with about thirty years of operation, that operate in way a little efficient for the current parameters, mainly in her air conditioning system. In that construction (in study), her system of environmental conditioning represents an increment in the energy demand of about 60%, passing to the 450.000 kWh/month for 750.000 kWh/month, and the change of those equipments for more modern and efficient, it would mean great investments, becoming unviable in the short period. With that, a prototype was elaborated containing automation devices, that can be incorporate to the existent system, without great difficulties, and minimizing the operational costs with the system. Those devices allow a more efficient monitoring, without the need of those investments, as the substitution of great equipments (compressors, chillers, etc.) that they part of the system of air conditioned central. That prototype allowed to demonstrate that with the application of those incorporate devices in those systems, they can generate an economy of about 20% in the electric power consumption, that represents a quite significant economy of 60.000 kWh/month, (this case) when operated the system of conditioned air, besides relieving the human resources made available for that monitoring type / Doutorado / Recursos Hidricos, Energeticos e Ambientais / Mestre em Engenharia Civil
10

Thermal rehabilitation of Romanian housing: a low cost assessment tool

Cobirzan, N., Oltean-Dumbrava, Crina, Brumaru, M. January 2012 (has links)
The numerous buildings that currently require thermal rehabilitation in Romania means that substantial resources and a large number of competent people are required to carry out surveys and energy audits. However, commercial energy balance software is mostly unaffordable for those organisations involved in this process. This paper describes an energy balance programme – ENEFControl – developed to be a rapid, low cost, local tool able to assist in the choice of energy efficient solutions for buildings. To test the software, thermal and energy analyses were carried out on a 1970s built apartment block in Transylvania. Based on these analyses, three constructive scenarios were proposed for thermal rehabilitation. Compared to the performance of the analysed building, the thermal and energy performance of the retrofitted building in all three scenarios significantly improved. Since European Union accession in 2007, rapidly rising energy costs have affected the Romanian population. ENEFControl offers Romanian engineers and architects an opportunity to speed up the rehabilitation programme of buildings without the need for more expensive expertise and tools.

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