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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

Energy demand and indoor climate of a traditional low-energy building in a hot climate

Li, Ang January 2009 (has links)
Energy demand in the built environment is quite important. China holds a large population and the energy use in the building sector is about 1/3. The rebuilding of old houses and building new low energy houses are becoming more and more popular in China. Low energy building not only consumes less energy, but also provides good indoor environment. An indoor climate software IDA is used in energy and indoor climate simulation. The traditional high isolated low energy house in a hot climate is analyzed, on a typical day in either summer or winter, or during the whole year. Energy consumptions under different parameters are presented. Results show that high isolated house may not always be suitable in a hot climate.
2

Hotel Nábřeží u Kunovské přehrady / Hotel Nábřeží at Kunov dam

Dananaiová, Ladislava January 2020 (has links)
In this diploma thesis is designed a hotel with a restaurant in the recreational areaKunov,close to Senica town. It has a capacity for 50 guests. The smallest rooms are double bedrooms with at least 16 m2anda bathroom 4m2. It is four stars hotel. There are three over ground floors and a basement. On the ground floor there is a reception, toilets, a restaurant for 65 guests. There is also a kitchen and storerooms. There are 5 hotel rooms on the first floor and an office. On the second and third floors there are hotel rooms, common room, cleaning room and laundry room. On the second and third floor there is one wheelchair accessibleroom. In the basement there are utility rooms, storerooms, a workshop, a gym with locker rooms and showers. The main entrance to the building is wheelchair accessible and leads to the reception. There is also a staff entrance from the back of the building and an entrance to the garden with a hotel pool. The roof is designed as a single layer flat roof. On the grounds there are designed outside showers, toilets for men and women and a garden shelter.
3

Integruotas grunto ir mažaenergio pastato atliekinės šilumos panaudojimas / Integrated usage of ground and surplus heat in low energy building

Gataveckas, Kipras 10 June 2014 (has links)
Baigiamajame magistro darbe nagrinėjamos grunto ir atliekinės pastato šilumos panaudojimo galimybės mažaenergiame pastate, Vilniaus mieste, Lietuvoje. Suskaičiuoti keturi pastato energijos balansų variantai, naudojant ”CASAnova” kompiuterinę skaičiavimo programą, su skirtingais atitvarų šilumos perdavimo koeficientais. Pastate taikomos dvi energijos taupymo priemonės. Pirmoji yra gruntinis šilumokaitis naudojamas šviežio oro pirminiam pašildymui mechaninio vėdinimo sistemoje, kurio skaičiavimai atliekami ”GAEA” programa. Antroji yra nuotekų šilumos atgavimo šilumokaitis, naudojamas į pastatą tiekiamo šalto vandens pirminiam pašildymui, atgaunant dalį šilumos iš duše susidariusių nuotekų. Pastatui reikiamas metinis šilumos ir vėsos energijos kiekis gaminamas šilumos siurbliu su vertikaliu gręžiniu grunte, kurio skaičiavimams naudojama ”EED” programa. Gręžinių gyliai yra suskaičiuoti kiekvienam pastato energijos balansų variantui. Atlikti ekonominiai skaičiavimai rodo gruntinio ir nuotekų šilumos atgavimo šilumokaičių įdiegimo pastate ekonominę naudą. Pateikti rezultatai rodo kiekvieno varianto energijos poreikius ir gręžinio grunte gylį priklausomai nuo pastato varianto atitvarų šiluminių savybių bei taikomų energijos taupymo sprendimų. Darbą sudaro 9 dalys: įvadas, 6 skyriai, išvados ir pasiūlymai, literatūros sąrašas. Darbo apimtis – 64 psl. teksto, 41 paveikslai, 14 lentelės, 31 bibliografinis šaltinis. / The final master thesis presents technical analysis of low-energy residential building in Vilnius, Lithuania. Building has low temperature floor heating, mechanical ventilation with heat recovery unit and hot water preparation with buffer tank systems. Using “CASAnova” software is calculated fourth energy balances of building according fourth different heat transfer coefficients of the walls. All heating and cooling energy demand of a building is generated from the ground. It is made by using a heat pump with single borehole. A calculation of borehole sizing is made with “EED” software. Two energy saving technologies are analysed for a building. The first idea is to reduce heat energy consumption of hot water preparation. There is calculated benefit of waste water heat recovery heat exchanger which function is to pre-heat hot water using waste water from the shower. Second idea is to reduce heat energy consumption for fresh air heating in air handling unit. There is calculated benefit of earth-to-air heat exchanger using “GAEA” software. Final result of all calculations shows influence of heat transfer coefficient and energy saving technologies to building annual energy balance and depth of borehole. Economic benefit of using energy saving technologies is calculated. Structure: introduction, 6 chapters, conclusions and suggestions, references. Thesis consists of 64 p. of text, 41 figures, 14 tables and 31 bibliographical entries.
4

Studie av lågenergibyggnader inför projektering av nära-nollenergi förskolor / Study of low energy buildings in preparation of near zero energy preschool projects

Nilsson, Daniel, Hallberg, Vilhelm January 2016 (has links)
Purpose: Production and utilization of buildings contributes immensely to global carbon dioxide emissions. The construction sector today accounts for over a third of global energy use will increase as the world population increases. According to the EU Directive from 2010, all new buildings in EU member countries as of December 31, 2020 are to be classified as near-zero energy buildings (NZEB). The goal is to investigate the various energy-affecting measures of the involved architects, structural engineers and planners that can improve the energy performance of a kindergarten to be closer to near-zero and identify obstacles that make it more difficult to achieve NZEB. Method: The investigation strategies for the project are qualitative methods in the form of semi-structured interviews with architects, planners and ventilation engineers for six different kindergartens. The interviews were conducted by telephone in which the questions were sent in advance to those interviewed. Mail interviews were conducted early on which resulted in either short answers or not answers at all. The energy performance documents of the different kindergartens were analyzed to get information about the different energy performances. Findings: The result does not contain a solution as to what the near-zero energy definition is or how to define it, but is more like guidance concerning what factors you can influence to get closer to near-zero energy for a kindergarten. Recurring problems surfacing in the interviews is that not all the involved roles have been able to influence predetermined choices of shape and space that, among other things, contribute to a limited space for services that planners are having difficulty influencing afterwards. Implications: The result helps contribute to making sure buildings are built in a more energy-efficient way and by such reducing the construction sector's share of the global energy consumption. The building's energy efficiency may not contribute to poor indoor climate in such a way that it affects children's health in a negative manner. This results in a need for careful planning where all parties can contribute with their best energy efficiency solutions without being too limited by the architectural constraints of shape and space. Alternatively, better communication between planners and architects in the earlier stages. Good planning contributes to a better result. Limitations: The result is based on Swedish kindergartens in a Nordic climate and should not be applied in countries without a Nordic climate. The result is not only applicable to kindergartens but is largely applicable to most similar buildings. Contact with more architects, constructional engineers, planners and more kindergartens would have given a better result.
5

Multi-dimensional approach used for energy and indoor climate evaluation applied to a low-energy building

Karlsson, Fredrik January 2006 (has links)
The building sector alone accounts for almost 40% of the total energy demand and people spend more than 80% of their time indoors. Reducing energy demand in buildings is essential to the achievement of a sustainable built environment. At the same time, it is important to not deteriorate people’s health, well-being and comfort in buildings. Thus, designing healthy and energy-efficient buildings is one of the most challenging tasks. Evaluation of buildings with a broad perspective can give further opportunities for energy savings and improvement of the indoor climate. The aim of this thesis is to understand the functionality, regarding indoor climate and energy performance, of a low-energy building. To achieve this, a multi-dimensional approach is used, which means that the building is investigated from several points of views and with different methods. A systems approach is applied where the definition of the system, its components and the border to its environment, is essential to the understanding of a phenomenon. Measurement of physical variables, simulations, and qualitative interviews are used to characterize the performance of the building. Both energy simulation and computational fluid dynamic simulations are used to analyse the energy performance at the building level as well as the indoor climate at room level. To reveal the environmental impact of the low-energy building studied in this thesis the CO2 emissions and embodied energy have been investigated regarding different surrounding energy systems. The evaluated building is situated at the west coast of Sweden and uses about 50% of energy compared to a comparable ordinary Swedish building. The building is well-insulated and an air-to-air heat exchanger is used to minimise the heat losses through ventilation. The houses are heated mainly by the emissions from the household appliances, occupants, and by solar irradiation. During cold days an integrated electrical heater of 900 W can be used to heat the air that is distributed through the ventilation system. According to measurements and simulations, the ventilation efficiency and thermal environment could be further improved but the occupants are mostly satisfied with the indoor climate. The control of the heating system and the possibility for efficient ventilation during summertime are other important issues. This was found through quantitative measurements, simulations and qualitative interviews. The low-energy building gives rise to lower CO2 emissions than comparable buildings, but another energy carrier, such as district heating or biofuel, could be used to further improve the environmental performance of the building. The total energy demand, including the embodied energy, is lower than for a comparable building. To understand the functionality of a low-energy building both the technical systems and the occupants, who are essential for low-energy buildings, partly as heat sources but mainly as users of the technical systems, should be included in the analysis.
6

Utvärdering av befintliga passivhus : En byggnadsfysikalisk bedömning och mätningar om temperatur, och fukt analys på ytterväggarna

Husseini, Hazhar January 2012 (has links)
Energy price are on the way up to a high level that will not diminish in the future make us to focus more on the sustainable development for a better solution of residential houses. Passive house or low energy housing are one of the solution to make residential more environment friendly, in same time it´s a financial security using less energy, and saving money. The last 10 years in Germany and all around Europe the concept of passive house been developed, and people aim to know more about these concept that leading the market more attractive for passive houses. A passive house is a well designed building highly insulated and air tight with mechanical ventilated system for the whole building envelope that minimizes the use of energy for heating [1]. The housing company Mimer has chosen to invest in low energy consumption in every new housing project.  These future plan projects are decided to use less than 75 kwh per square meter annually in purchased energy [2]. This thesis is about new constructed passive houses, and focuses on the evaluations of the temperature, and moisture condition for attic, external walls and joist. Reason for doing this investigation is to see if passive houses fulfill the building codes regarding moisture, and temperature changes, and to find in early stage suspicious changes that could affect badly on the building envelop. The aim of this study is -         Moisture risk analyses of the attic, external walls and joist -         Studying temperature analysis   With highly insulated walls the risk for moistures extra sensitive than normal building construction.  Also during summer time the comfort inside may be surprised by high indoor temperature and one solution for that could be using sun shading.
7

Mažaenerginio administracinio pastato sezoninės energijos poreikių ypatybės / Seasonal Peculiarities of Energy Demands of a Low Energy Office Building

Subačiūtė, Ieva 20 July 2012 (has links)
Baigiamajame magistro darbe nagrinėjamas mažaenergis administracinis pastatas ir AEI panaudojimo jame galimybės Lietuvos meteorologinėmis sąlygomis. Naudojant modeliavimo priemonę TRNSYS sukuriami mažaenerginio administracinio pastato bei AEI sistemų skaičiavimo – valdymo modeliai: saulės kolektoriai, foto elementai, vėjo jėgainės, šilumos siurbliai, imantys šilumą iš grunto bei oro. Atlikus modeliavimą gauti pastato energijos suvartojimai šildymui (54 kWh/m2), vėsinimui (20 kWh/m2) bei elektros (48 kWh/m2). Metiniame pastato energijos balanse, energija pagaminta iš AEI gali padengti 56,6% reikalingos šiluminės energijos, 102,9 % energijos reikalingos vėsinimui ir 4,5 % reikalingo elektros kiekio. Pastato energijos poreikių jautrumo analizė atliekiama 3 pastato variantams. Pastebėta, kad esant didesniam stiklinių atitvarų plotui pietinėje pastato pusėje pagamintas šilumos kiekis iš AEI gali padengti net 85 % pastatui reikalingo šilumos kiekio. Tačiau beveik du kartus išaugo energijos poreikis pastato vėsinimui. Mažiausias vėsinimo kiekis reikalingas stačiakampio ploto pastatui. Apibendrinus rezultatus, pateiktos išvados ir rekomendacijos. Darbą sudaro 5 dalys: įvadas, 5 skyriai, išvados ir rekomendacijos, literatūros sąrašas. Darbo apimtis – 63 p. teksto be priedų, 31 iliustr., 16 lent., 27 bibliografiniai šaltiniai. Atskirai pridedami darbo priedai. / Thesis examined low energy office building and possibilities of renewable energy use in it by Lithuanian meteorology conditions. Using TRNSYS simulation tool the computing-control models for low energy office building and renewable energy systems (RES) (solar collectors, photovoltaic, wind turbines and heat pumps taking the heat from the soil and air) are created. After the simulation buildings’ energy consumption for heating (54kWh/m2), cooling (20 kWh/m2) and electricity (48 kWh/m2) were obtained. The annual building energy balance: an energy produced from RES can cover 56.6 % of the necessary thermal energy, 102.9 % of the energy required for cooling and 4.5 % required for electricity generation. The buildings’ energy demand sensitivity analysis is performed for three buildings’ variants. It is observed that of a larger area of the glass envelope of the building in southern direction the amount of heat produced from RES can cover up to 85% of the building required heat. However, almost twice rises electricity demand in cooling of the building. The minimum amount of cooling is required for a rectangular area building. Summarizing the results, conclusions and recommendations are presented. The work consists of 5 parts: introduction, 5 chapters, conclusions and recommendations, references. Work size – 63 pages without appendices, 31 figures, 16 tables, 27 references. Appendices.
8

Analyse de la fiabilité des outils de simulation et des incertitudes de métrologie appliquée à l'efficacité énergétique des bâtiments / Analysis of simulation tools reliability and measurement uncertainties for Energy Efiiciency in Buildings

Spitz, Clara 09 March 2012 (has links)
Le recours à la simulation est décisif dans le processus de conception d'un bâtiment neuf. Elle permet d'évaluer différentes alternatives au regard de la performance énergétique et du confort des occupants et constitue ainsi un outil d'aide à la décision incontournable. Aujourd'hui la question de la fiabilité des codes de simulation n'est pas à négliger. L'augmentation des performances énergétiques des bâtiments, pourrait mettre en défaut un certain nombre d'hypothèses de modélisation généralement admises pour les bâtiments standards du fait de la prépondérance nouvelle de phénomènes physiques jusqu'alors négligés ou mal pris en compte. Dans le même temps on s'intéresse de plus en plus à la garantie de performance qui consiste à vérifier que les performances énergétiques réelles sont bien en adéquation avec les objectifs fixés lors de la conception or il est souvent constaté des erreurs entre consommation mesurée et estimée compte tenu des incertitudes liées notamment à la mise œuvre, aux occupants et aux conditions météorologiques. L'augmentation des exigences de précision des calculs qui en résulte rend essentiel d'apprécier les incertitudes associées à ces prévisions afin d'améliorer le processus de construction et d'évaluation. Les travaux de cette thèse portent en particulier sur l'évaluation et la hiérarchisation des incertitudes sur les résultats des simulations en phase de conception. Une méthodologie a été développée basée en trois temps qui permet d'identifier les paramètres de conception les plus influents sur la performance énergétique d'un bâtiment et de rendre compte des effets de l'incertitude associée à ces paramètres sur cette même performance. La première étape consiste à identifier parmi l'ensemble des paramètres du modèle ceux qui ont une influence sur le résultat qui nous intéresse. Celle-ci est assurée au moyen d'une analyse de sensibilité locale du modèle. La deuxième étape consiste à évaluer les incertitudes associées à ces paramètres les plus influents afin de propager cette incertitude dans le code de calcul et évaluer l'incertitude sur le résultat. Cette étape est effectuée au moyen d'approches probabilistes de type Monte Carlo. Nous ajoutons une troisième étape de manière à évaluer la responsabilité de chacun des paramètres sur les incertitudes associées au résultat. Cette information est cruciale pour l'utilisateur. Cette dernière étape est traitée au moyen d'une analyse de sensibilité globale sur un jeu de paramètres réduit. Nous nous sommes appuyés sur la plateforme expérimentale INCAS située à l'INES au Bourget du Lac (73) pour identifier les incertitudes de mesure mais aussi les incertitudes dont les hypothèses de modélisation font l'objet. Cette méthodologie pourra être utilisée durant tout le processus de conception d'un bâtiment, des premières esquisses à son exploitation. En phase de conception, cette méthodologie permettra d'orienter les choix architecturaux en évitant des options dont la fiabilité des résultats est incertaine. En phase d'exploitation, elle permettra d'identifier les points de mesure les plus pertinents, afin de réduire l'incertitude des paramètres les plus influents pour effectuer un diagnostic énergétique plus fiable du bâtiment. Elle pourra aussi s'étendre aux incertitudes liées aux occupants et aux conditions météorologiques. / Nowadays, simulation tools are widely used to design buildings since their energy performance is increasing. Simulation is used to predict building energy performance and to improve thermal comfort of occupants, but also to reduce the environmental impact of the building over its whole life cycle and the cost of construction and operation. Simulation becomes an essential decision support tool, but its reliability should not be ignored. Hypothesis, made 10 years ago for buildings conception, are often not adapted to the new constructions because of physical phenomena which until now were overlooked. At the same time, guarantees of energy efficiency, which aims to check if actual energy performances are matching the conception goals, are becoming important. But there are usually differences between measured and simulation data. They may be the result of mistakes and unknowns on input parameters, on schedule occupation or on weather data. Today it's important to evaluate simulation and measurement reliability and uncertainties to improve design building. This PhD work aimed to evaluate and order simulation results uncertainties during the design building process. A methodology in three steps was developed to determine influential parameters on building energy performance and to identify the influence of these parameters uncertainty on the building performance. The first step uses the local sensitivity analysis and identifies the most influential parameters on the outputs among all parameters. This step enables to reduce the number of parameters which is necessary to proceed the following steps The second step is an uncertainty analysis focuses on quantifying uncertainty in model outputs. This step is conducted with the Monte Carlo probabilistic approach. The last step uses global sensitivity analysis which is the study of how uncertainty in the output of a model can be apportioned to different sources of uncertainty in the model input. This methodology was applied to the INCAS experimental platform of the French National Institute of Solar Energy (INES) in Le-Bourget-du-Lac to identify measure uncertainties and uncertainties on simulation hypothesis. This methodology may be used during the whole building design process, from the first sketches to the operating phase. It will enable to guide the architectural and technical choices and to avoid unstable options with important uncertainty. During the exploitation stage, this methodology will allow to identify the most suitable measurement in order to reduce parameters uncertainties and consequently to get the energy diagnostic more reliable. Moreover this methodology could also be used to determine uncertainties on related to inoccupants and to weather conditions.
9

Indigenous Materials in Modern Buildings : for low energy houses in West Africa

Persson, Staffan January 2014 (has links)
Burkina Faso is one of the poorest countries in the world. This landlocked country in the west has an extremely warm climate. Temperatures over 45°C are not uncommon and there is an almost constant need to keep the buildings cool to maintain a temperate indoor climate. Air-conditioning is an option to maintain the temperature but it overloads the power grid and only a few people can afford it. This thesis examines, through laboratory experiments, the thermal and mechanical properties that can be obtained by vibrating clayey soil and mixing it with water, lime or cement and organic fiber (Bissap). The report also examines different building projects utilizing local materials, both of a traditional and more modern nature.Energy required to produce building elements of soil is negligible compared to that of concrete and steel. Soil can be used in constructing houses but it is sensitive to water.The insulation is inadequate for a passive house so an extra layer of insulating material is required.The experiments performed during this project were inconclusive so it is impossible, from the results in this paper, to say if vibration is a good method for forming a building material of soil. The high water content needed, is however a major problem, shrinkage was about 20% and cracks were hard to avoid. Further investigations into the subject is necessary. / Burkina Faso är ett av de fattigaste länderna i världen. Som ett kustlöst land beläget i Västafrika har det ett extremt varmt klimat. Temperaturer över 45°C är inte ovanligt och det är ett nästan konstant behov av att kyla byggnader för att behålla ett behagligt inneklimat.   Idag byggs det två typer av byggnader i Burkina Faso; de traditionella lerhusen och de mer moderna husen med väggar av cementstenar och plåttak. Cementväggarna har ett U-värde på 3W/m2K och tillsammans med plåttaket så bildar det ett undermåligt klimatskal utan möjligheter att skydda mot hettan. Det leder idag till endera ett obehagligt varmt inneklimat eller en hög och kostsam energianvändning av luftkonditionering. Överbelastningen på elnätet på grund av luftkonditionering är påtaglig under den varmaste säsongen med frekventa strömavbrott till följd.   Denna rapport undersöker via laboratorieexperiment vilka termiska och mekaniska egenskaper man kan erhålla genom att vibrera lerjord och blanda med vatten, organiska fibrer samt kalk och/eller cement. Litteraturstudier och fältbesök i Burkina Faso har gjorts för att undersöka och förstå vilka svårigheter som kan uppkomma genom att bygga med lera. Rapporten tar även upp konkreta exempel på byggnader i Burkina Faso gjorda av lokala material, historiska såväl som moderna projekt.   Lerjord behöver extremt lite energitillförsel för att bilda ett byggmaterial och den negativa miljöpåverkan är försumbar jämfört med betong och stål. Det kan användas för att bygga energisnåla hus men det är känsligt mot vatten, vilket måste beaktas noga under projekteringen. Värmeledningsförmågan är för hög för att vara tillräcklig som isolering för att erhålla ett inneklimat enligt dagens standard, utan tillförsel av energi, så någon form av extra isolering krävs.   Experimenten som gjordes gav inte tillräckligt exakta resultat för att visa om vibrering är en bra metod att göra byggmaterial eller inte. Den höga vattenhalten som krävs för vibrering är ett stort problem. Krympningen var ungefär 20 % och sprickor var svåra att undvika. Vidare studier på området rekommenderas.
10

Nízkoenergetická výstavba / Low-energy building

Lattenberg, Marek January 2013 (has links)
Diploma thesis "Low-energy building" presents low-energy construction trends and their price comparision with conventional contruction. This thesis defines basic low-energy building terms, both building and construction work evaluation concepts and specifics of low-energy construction. Practical outcome is comparision between passive and conventional buildings, including economic appraisal.

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