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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.
61

The impact from varying wind parameters and climate zones on building energy use : A case study on two multi-family buildings in Sweden using building energy simulation

Tamilvanan, Karthickraj, Mathipadi, Sai Kiran January 2020 (has links)
Globally, buildings utilize 35 % of the final energy use and contribute to approximately one-third of CO2 emissions. Hence, reducing the energy use of buildings contributes to a large amount of CO2 emissions to be decreased. The building’s energy use is affected by many parameters, including wind which plays an important role in building energy use. In this thesis, we aim to analyze the impact of wind parameters on building’s energy use on two multi-family building types with natural ventilation at various wind sheltering conditions at different climatic zones in Sweden. Building energy simulation models (BES) of a standalone and an attached building located in Visby, Sweden, were constructed with the use of the dynamic BES IDA ICE. Luleå and Malmö were taken as other two study locations to investigate the impact from different climate zones. The simulations were performed with the constructed calculation models, with the various wind sheltering conditions at the different climatic zones to calculate the energy use of the buildings and ventilation and infiltration losses. The sensitivity analysis was then carried out based on changing the wind profile of the climate file to evaluate the impact of wind on the ventilation and infiltration losses, as well as the heat energy use of the building. The results showed that the energy use for space heating of the attached building was 89 kWh/m2 (38 %) lower than the standalone building. The energy use varies between 9–20 kWh/m2 (3–10 %) considering the exposed, semi-exposed and sheltered wind condition for the two building types. In the different climate zones, Luleå has 47 kWh/m2 higher energy use compared to Visby and Malmö for the standalone building. The corresponding figure for the attached building is 25 kWh/m2. The sensitivity analysis show that when the wind speed is increased by 100 %, the ventilation and infiltration losses increase between 3563–18683 kWh (54–61 %) while the energy use of the building increases between 11–54 kWh/m2 (20–27 %).
62

Energy Performance Simulation of Different Ventilation Systems in Sweden and Corresponding Compliance in the LEED Residential Rating System

Boyle, Patrick January 2020 (has links)
The importance of energy efficiency in the operation of the built environment is becoming increasingly important. Energy use in the building sector has exceeded both transportation and industry, while within buildings heating, ventilation, and air conditioning has the greatest share. In light of the recent pandemic forcing governments to issue quarantines and stay-at-home orders people are spending even more time indoors, this further emphasizes the importance of proper ventilation and the impacts on energy use. The purpose of this research was to perform a case study of a low environmental impact demonstration house to compare the energy performance of various ventilation strategies. The ventilation strategies varied by overall airflow rate, control strategy, and the presence of heat recovery. Performance was evaluated by establishing a model in IDA ICE, an equation-based modeling tool for the simulation of indoor thermal climate and energy use. The results showed energy savings due to demand-control with a reduction of 12.5%. Results also showed similar savings with a heat recovery system, indicating that any savings in heat loss due to heat recovery is at the expense of increased auxiliary energy. In this particular case, the benefit of upgrading to a heat recovery system from simple demand control set up is not readily apparent. Results also demonstrated trends and possible complications useful to future research plans that aim to measure real world ventilation performance, including how differences in the number and location of sensors impact the efficacy of the demand-controlled systems. A secondary aim was to observe how a newly constructed, low environmental impact home built in Sweden performs according the residential LEED energy budget. The results demonstrated that constructing a house using low impact materials with low embodied energy does not have to negatively impact energy performance, scoring extremely well in the Energy and Atmosphere category of a widely used sustainable building rating system.
63

3D-Modeling and Energy Simulation of a Single Family House in Southern Greece

Liotsios, Kyriakos January 2012 (has links)
Energy usage deriving from human activities is increasing day by day acting against the quality of the environment and the sustainable use of natural resources. The major impact of these actions is reflected on the quality of daily life. In order to face the challenge of preserving an acceptable balance between human needs and environmental status, the combination of proper design and energy simulation of buildings is the key towards smarter and more sustainable solutions. Solutions that covers a respectable percentage of the current domestic energy needs without further environmental foot printing. In the scope of this project, an existing single-family house in Southern Greece (Heraklion, Crete) is modeled using Revit ® Architecture software and then is simulated with IES® VE (plug-in) in order to give the level of energy intensity. The energy model used is fully harmonized with the new rules set by the "National Regulation for Energy Performance of Buildings - (K.En.A.K)" as it was put in force from October 2010 and onwards, and fully complies with the European Standards (EN ISO) published for the various tasks of building`s thermal performance. The structure and contents presented in this report are in full compliance with the technical directives [31, 32, 33] published by the Technical Chamber of Greece, in favour of the complex task of "Energy Certification of Buildings". The most significant capabilities of sophisticated software tools, like Revit® Architecture, IES® VE, Polysun® and PVsyst®, in favour of sustainable building design and simulation are shown throughout the whole report. Moreover, their valuable contribution is highly acknowledged by the engineers encountered with the task of studying the energy performance of existing or newly constructed buildings in Greece and issuing, the mandatory by law, "Energy Performance Certificates".
64

Demonstrating the significance of microclimate on annual building energy simulations using RadTherm

Sommerfeldt, Nelson January 2012 (has links)
Buildings account for over 35% of the energy demand in OECD countries, making them a prime target for improvement. (EIA 2011) To help building owners reduce energy usage, ratings systems such as LEED have been developed. A prerequisite for certification is the demonstration of energy efficiency through computer modeling; however, the complex nature of building energy simulations too often leads to errors of up to 30% (Turner and Frankel 2008). One source of significant error can be the assumptions made of environmental conditions, which are often simplified to speed up simulations. To demonstrate the significance of active microclimate modeling, a building energy model combined with a microclimate model has been created in RadTherm, a commercial CAE thermal solver. Simulations are run using Passive House construction in three types of environments, and demonstrate an increase in energy demand over an annual time scale when microclimatic components are included. The increase in demand is less than 1%, however the decrease in radiant heat losses are up to 30%. Using the same methodology with revisions to the building construction and urban geometry, a larger increase in energy demand is expected.
65

Développement d’une méthodologie pour la garantie de performance énergétique associant la simulation à un protocole de mesure et vérification / Methodology for energy performance contracting based on simulation and a measurement protocol

Ligier, Simon 28 September 2018 (has links)
Les écarts communément observés entre les prévisions de consommations énergétiques et les performances réelles des bâtiments limitent le développement des projets de construction et de réhabilitation. La garantie de performance énergétique (GPE) a pour vocation d’assurer des niveaux de consommations maximaux et donc de sécuriser les investissements. Sa mise en place fait cependant face à plusieurs problématiques, notamment techniques et méthodologiques. Ces travaux de thèse se sont intéressés au développement d’une méthodologie pour la GPE associant les outils de simulation énergétique dynamique (SED) à un protocole de mesure et vérification. Elle repose d’abord sur la modélisation physico-probabiliste du bâtiment. Les incertitudes sur les paramètres physiques et techniques, et les variabilités des sollicitations dynamiques sont modélisées et propagées dans la SED. Un modèle de génération de données météorologiques variables a été développé. L’étude statistique des résultats de simulation permet d’identifier des modèles liant les consommations d’intérêt à des facteurs d’ajustement, caractéristiques des conditions d’exploitation. Les méthodes de régression quantile permettent de déterminer le quantile conditionnel des distributions et caractérisent donc conjointement la dépendance aux facteurs d’ajustement et le niveau de risque de l’engagement. La robustesse statistique de ces méthodes et le choix des meilleurs facteurs d’ajustement ont été étudiés, tout comme l’influence des incertitudes sur la mesure des grandeurs d’ajustement en exploitation. Leur impact est intégré numériquement en amont de la méthodologie. Cette dernière est finalement mise en œuvre sur deux cas d’étude : la rénovation de logements, et la construction de bureaux. / Discrepancies between ex-ante energy performance assessment and actual consumption of buildings hinder the development of construction and renovation projects. Energy performance contracting (EPC) ensures a maximal level of energy consumption and secures investment. Implementation of EPC is limited by technical and methodological problems.This thesis focused on the development of an EPC methodology that allies building energy simulation (BES), and measurement and verification (M&V) process anticipation. The building parameters’ uncertainties and dynamic loads variability are considered using a Monte-Carlo analysis. A model generating synthetic weather data was developed. Statistical studies of simulation results allow a guaranteed consumption limit to be evaluated according to a given risk. Quantile regression methods jointly capture the risk level and the relationship between the guaranteed energy consumption and external adjustment factors. The statistical robustness of these methods was studied as well as the choice of the best adjustment factors to consider. The latter will be measured during building operation. The impact of measurement uncertainties is statistically integrated in the methodology. The influence of M&V process accuracy is also examined. The complete EPC methodology is finally applied on two different projects: the refurbishment of a residential building and the construction of a high energy performance office building.
66

Avaliação técnica e financeira da geração fotovoltaica integrada à fachada de edifícios de escritórios corporativos na cidade de São Paulo / Technical and financial evaluation of Building-Integrated Photovoltaics (BIPV) in corporate buildings in the city of São Paulo

Santos, Arthur Henrique Cursino dos 17 November 2015 (has links)
As edificações comerciais, públicas e residenciais foram responsáveis em 2014 por 50% do consumo de eletricidade no país. Considerando os últimos dez anos, enquanto o consumo médio dos diferentes setores da economia cresceu 3,5% ao ano, o consumo do setor comercial cresceu 5,4%. Os edifícios de escritórios corporativos representam grandes consumidores de energia, chegando a valores superiores aos 200 kWh/m2.ano. A geração distribuída é uma solução que vem sendo estudada no país, primeiramente pela aprovação da Resolução Técnica 482:2012 da ANEEL, que regulamenta a geração de eletricidade na baixa tensão e depois pela aprovação da Portaria 381:2015 que dispõe sobre a geração de eletricidade na média tensão. Apesar do crescimento da geração por fontes fotovoltaicas no mundo, no Brasil essa geração ainda é mínima frente às fontes hídricas e térmicas. Nos edifícios de escritórios corporativos a instalação de painéis fotovoltaicos na cobertura é bastante limitada, devido à disputa de espaço com outros serviços, como as áreas técnicas e heliponto. Nesse contexto, as fachadas aparecem como oportunidade para geração de eletricidade, através da tecnologia fotovoltaica integrada na arquitetura (BIPV). Nesse estudo foi avaliada a viabilidade técnica e financeira da geração integrada à arquitetura dos edifícios de escritórios corporativos da cidade de São Paulo a partir do uso de vidros fotovoltaicos. Os resultados indicam que existe um potencial de redução de 15% no consumo de eletricidade anual, considerando tanto a geração de eletricidade, quanto a redução do consumo do sistema de ar condicionado, que tem sua carga térmica reduzida com o uso dos vidros fotovoltaicos. A tecnologia já é viável financeiramente no mercado brasileiro quando associada ao vidro refletivo, apresentando um tempo de retorno simples de 2,9 anos, uma TIR de 34,2% e um VPL de 1.779.257,53, para um edifício em torre com 28.010 m2 de área condicionada e 21 andares. / Commercial, public and residential buildings accounted in 2014 for 50% of electricity consumption in Brazil. Considering the last ten years, while the average consumption of the different sectors of the economy increased by 3.5% per year, the consumption of the commercial sector grew 5.4%. Corporate buildings are major energy consumers, reaching values in the range of 200 kWh/m2.year. Distributed generation is a solution that has been studied in the country, primarily with the approval of the Technical Resolution 482:2012, which regulates the generation of electricity at low voltage and then with the approval of the General Ordinance 381:2015 which regulates the generation of electricity at medium voltage. Despite the growth in generation from photovoltaic sources in the world, in Brazil this generation is still minimal when compared to other sources, like hydro and thermal plants. In commercial buildings, the space to install photovoltaic panels on the roof is quite limited. In this context the facades appear as an opportunity to generate electricity through photovoltaic technology integrated in the architecture (BIPV). In this study we evaluated the technical and financial feasibility of the integrated generation to the architecture of corporate buildings in the city of Sao Paulo. The results indicate a 15% reduction potential in annual electricity consumption, considering both the electricity generation and the reduction of the consumption by the air conditioning system, which has a reduced thermal load when photovoltaic glass is used. The BIPV technology is already feasible in the Brazilian market when coupled with reflective glass, showing a simple payback of 2.9 years, an IRR of 34.2% and a NPV of 1,779,257.53, for a building with 28,010 m2 and 21 floors.
67

Eficientização de um sistema de climatização aeroportuário a partir do uso da termoacumulação

Dombrosky, Robson Fernandes January 2012 (has links)
Submitted by William Justo Figueiro (williamjf) on 2015-06-26T22:57:56Z No. of bitstreams: 1 43.pdf: 3316113 bytes, checksum: 59a696189af2b9803f0adedd6828d93e (MD5) / Made available in DSpace on 2015-06-26T22:57:56Z (GMT). No. of bitstreams: 1 43.pdf: 3316113 bytes, checksum: 59a696189af2b9803f0adedd6828d93e (MD5) Previous issue date: 2012 / Banco Santander / Banespa / O trabalho apresenta um estudo do sistema de climatização do aeroporto da cidade de Porto Alegre, visando determinar e mensurar as oportunidades de redução dos seus custos operacionais utilizando o tanque de termoacumulação já existente, recurso que por razões diversas encontra-se atualmente inoperante. Para possibilitar uma avaliação global do comportamento do sistema em estudo, tanto a edificação do terminal de passageiros quanto os equipamentos integrantes da sua planta de climatização foram modelados e simulados através do programa EnergyPlus, com uso de arquivo climático específico para a cidade de Porto Alegre. As simulações ratificaram as previsões de que o sistema de climatização do aeroporto de Porto Alegre trabalha atualmente com custos de operação superiores àqueles que poderiam ser obtidos caso o sistema de termoacumulação estivesse em operação. A economia integrada ao longo de um ano pela redução de custos com as faturas de energia do aeroporto atingiu R$ 312.206,00. Ficou evidente que a redução da demanda e consumo de energia em horário de ponta são as parcelas com maior representatividade na diminuição dos custos operacionais do sistema de climatização do aeroporto, respondendo, respectivamente, por 77% e 18% sobre todas as economias obtidas nas faturas de energia após o uso da termoacumulação. Constatouse que além da redução nos valores pagos pela utilização de energia elétrica em horário de ponta, a participação da termoacumulação possibilita também redução no consumo energético dos equipamentos da planta de climatização, motivada por estratégias de operação mais eficientes. Desta forma, considerando apenas os meses de verão, as simulações apontaram uma redução média de 11% no consumo referente aos equipamentos da planta de climatização. Se para o mesmo período forem também contabilizadas as economias devido redução de demanda e consumo em horário de ponta dos equipamentos de climatização, a redução total sobre a fatura de energia do aeroporto a partir do uso da termoacumulação situase em 30%. Outra importante questão relacionada ao uso da termoacumulação diz respeito à ampliação da capacidade frigorífica que a mesma proporciona ao sistema de climatização, efeito de elevada relevância para fazer frente ao aumento na movimentação de passageiros da aviação civil dos últimos anos. Nesse sentido, as simulações apontaram um incremento de cerca de 25% na capacidade de refrigeração da planta atual, após participação do tanque de termoacumulação. Tal efeito representa notória contribuição ao aumento da longevidade das instalações existentes, limitando ou eliminando a necessidade de maiores intervenções para aumento de capacidade de refrigeração da planta até o momento em que o terminal de passageiros venha a sofrer ampliações mais significativas. / The study presents the heating, ventilation and air conditioning system (HVAC) used in Porto Alegre city airport, aiming cost reductions opportunities due to its cool storage tank operation, a feature that for various reasons is currently out use. To enable a comprehensive assessment of the system’s behavior, both the passenger terminal building and HVAC equipment were modeled and simulated using the EnergyPlus software, along with the weather file that contains Porto Alegre’s meteorological data. The simulations have reaffirmed the predictions that Porto Alegre’s airport HVAC system is currently working with operating costs above those that could be obtained if the cool storage system were in operation. The integrated economy over a year by reducing costs to the electricity bills from the airport reached R$ 312.206,00. It became notorious that the reduction of demand and energy consumption during the peak hours are the most representative from all economies, accounting respectively for 77% and 18% of the total energy bills savings after cool storage tank operation. It was found that, besides the reduction in the amounts paid for electricity at peak hours, the participation of cool storage also enables reduction in energy consumption for HVAC plant equipments, driven by more efficient operating strategies. Thus, considering only the summer months, the simulations showed an average reduction of 11% in HVAC plant equipment consumption. As for the same period, if it is also accounted for the savings due to electric demand and consumption reduction during peak hours, the total energy bill reduction for the airport after applying the cool storage tank stands at 30%. Another important issue related to the use of cool storage is the HVAC cooling capacity increase, very relevant if considering the terminal passenger handling increase along last years. In that sense, the simulations showed a 25% increase in cooling capacity for the current system after the cool storage has joined the HVAC plant. This effect is a noticeable contribution to the existing installations longevity, as it limits or eliminates the need for further increase in the airport cooling capacity, not until the time when the passenger terminal may suffer significant enlargements.
68

Metodologia para análise termoeconômica de sistemas de resfriamento distrital. / Thermoeconomic methodology for district cooling systems analysis.

Santos, Arthur Garuti dos 18 March 2019 (has links)
Com o constante desenvolvimento das áreas urbanas e aumento do consumo energético destinado a conforto térmico, um estudo foi realizado para formulação de uma metodologia de análise termoeconômica de sistemas distritais de resfriamento. O objetivo principal é descrever uma metodologia referente à implantação de sistemas distritais no Brasil, por sua vez, o objetivo secundário é aplicar a metodologia no estado de São Paulo, analisando as premissas utilizadas na metodologia. Primeiramente, apresentou-se uma visão geral e revisão de literatura dos sistemas de aquecimento e resfriamento distrital, indicando suas vantagens e desvantagens, bem como as diversas aplicações e desafios para sua implantação. Aplicações no cenário mundial foram expostas e analisadas, demonstrando que sua utilização em diversos países se estende por décadas. As principais vantagens observadas nas aplicações existentes estão relacionadas a maior eficiência energética e exergética global, redução das emissões de gases poluentes e confiabilidade do sistema. Por fim, a metodologia aplicada está apresentada em cinco etapas, de forma ordenada, baseando-se nas etapas de um projeto de sistemas distritais. Seu resultado é baseado em rotinas, simulações de processos e procedimentos de otimização, bem como aplicação de indicadores energéticos. Ao final das etapas e seu desenvolvimento matemático obtém-se um estudo preliminar de viabilidade da implantação de um sistema distrital. O estudo de caso apresentado aplica a metodologia para a cidade de São Paulo buscando descrever com detalhamento as premissas e etapas descritas. / The constant development of urban areas and increased energy consumption for thermal comfort encourage studies that formulate a methodology for thermoeconomic analysis of district cooling systems. The main objective is to describe a thermoeconomic methodology related to the implementation of district systems in Brazil. The secondary objective is to apply the methodology in the state of São Paulo, analyzing the premises used in the methodology. At first, an overview and literature review of district heating and cooling systems was presented, indicating their advantages and disadvantages, just as the various applications and challenges for their implementation. Applications on the world stage have been introduced and analyzed, demonstrating that their use in several countries extends for decades. The main advantages observed in the existing applications are related to global energy and exergy efficiency, reduction in greenhouse gases and reliability of the systems. Finally, the applied methodology is presented in five steps in an orderly manner based on the steps of a district system project. Its result is based on routines, process simulations and optimization procedures, as well as application of energy indicators. At the end of the steps and their mathematical development a preliminary study of the feasibility of the implantation of a district system is obtained. The present case study applies the methodology for the city of São Paulo and describe in detail the premises and steps.
69

Orsaker till skillnad mellan projekterad och uppmätt specifik energianvändning : En jämförelsestudie för vård- och omsorgsboendet Furugården i Valbo

Källström, Martina, Skoog, Malin January 2015 (has links)
When an energy simulation is performed for buildings it generates in lower energy consumption than what is later measured. This can often be a problem because of the building regulations which have requirements on the specific energy consumption. What distinguishes the newly built care and nursing accommodation Furugården, the building that the study deals with, is that it is differs from the normal case by having a lower measured energy consumption than what was originally planned. This study aims to find out which parts of the building's technical systems and residents' behavior that contributes to the low energy demand by means of the building energy simulation program BV2, a survey and monitored energy consumption. It can be concluded that the users' behavior has a great impact on the building's low energy consumption. Their behaviors were determined by surveys. It is mainly the low hot tap water usage that contributes to the low energy.
70

Analysis of the Impact of Urban Heat Island on Energy consumption of Buildings in Phoenix

January 2011 (has links)
abstract: The Urban Heat Island (UHI) has been known to have been around from as long as people have been urbanizing. The growth and conglomeration of cities in the past century has caused an increase in the intensity and impact of Urban Heat Island, causing significant changes to the micro-climate and causing imbalances in the temperature patterns of cities. The urban heat island (UHI) is a well established phenomenon and it has been attributed to the reduced heating loads and increased cooling loads, impacting the total energy consumption of affected buildings in all climatic regions. This thesis endeavors to understand the impact of the urban heat island on the typical buildings in the Phoenix Metropolitan region through an annual energy simulation process spanning through the years 1950 to 2005. Phoenix, as a representative city for the hot-arid cooling-dominated region, would be an interesting example to see how the reduction in heating energy consumption offsets the increased demand for cooling energy in the building. The commercial reference building models from the Department of Energy have been used to simulate commercial building stock, while for the residential stock a representative residential model prescribing to IECC 2006 standards will be used. The multiyear simulation process will bring forth the energy consumptions of various building typologies, thus highlighting differing impacts on the various building typologies. A vigorous analysis is performed to see the impact on the cooling loads annually, specifically during summer and summer nights, when the impact of the 'atmospheric canopy layer' - urban heat island (UHI) causes an increase in the summer night time minimum and night time average temperatures. This study also shows the disparity in results of annual simulations run utilizing a typical meteorological year (TMY) weather file, to that of the current recorded weather data. The under prediction due to the use of TMY would translate to higher or lower predicted energy savings in the future years, for changes made to the efficiencies of the cooling or heating systems and thermal performance of the built-forms. The change in energy usage patterns caused by higher cooling energy and lesser heating energy consumptions could influence future policies and energy conservation standards. This study could also be utilized to understand the impacts of the equipment sizing protocols currently adopted, equipment use and longevity and fuel swapping as heating cooling ratios change. / Dissertation/Thesis / M.S. Architecture 2011

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