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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.
21

Power system impacts of plug-in hybrid electric vehicles

Roe, Curtis Aaron 08 July 2009 (has links)
Two studies are presented quantifying the impact of plug-in hybrid vehicles (PHEVs) on power systems. The first study quantifies this impact in terms of (a) primary fuel utilization shifts, (b) pollution shifts, and (c) total cost for consumers. The second study quantifies this impact on distribution transformers. In the first study vehicle and power system simulations are used to compute the expected power system fuels utilized to meet a projected level of power demand. The projected electric power demand includes business as usual electric load and random PHEV charging electric load. In the second study the impact on distribution transformers is quantified through a loss of life calculation. The loss of life calculation is based on distribution transformer hot-spot temperature. The hot-spot temperature is estimated using an electro-thermal distribution transformer model and is a function of the transformer currents. The transformer currents are computed using a center-tapped single phase transformer model. Random business as usual and PHEV charging electric loading is assumed.
22

Avaliação da inserção do gás natural no setor industrial brasileiro: uma análise de indicadores de impactos energético, ambiental e econômico. / Evaluation of the Natural Gas Insertion in the Brazilian Industrial Sector An Assessment of Energy, Environmental and Economic Impact Indicators.

Alexandre de Barros Gallo 31 January 2018 (has links)
O paradigma atual do uso da energia no setor industrial brasileiro é fruto da conjuntura histórica do setor energético no país e permite explicar algumas de suas características particulares, a utilização intensiva de eletricidade em processos térmicos, a eletrotermia, algo que perdura até hoje. O cenário nacional de produção de gás natural é promissor, no contexto do Pré-Sal, o que sinaliza uma oportunidade para aplicar esse recurso natural para usos energéticos com maior valor agregado, como por exemplo como energia final para a indústria. É neste contexto que se insere esta dissertação onde foi desenvolvida e aplicada uma técnica de análise de dados com objetivo de avaliar a inserção do gás natural no setor industrial brasileiro e seus impactos. A técnica de análise de dados desenvolvida constitui-se na avaliação de quatro indicadores: Demanda Adicional (DA); Impacto em Energia Primária (IEP); Impacto em Emissões de Carbono (IEC) e Impacto em Custo Energético (ICE). Nos resultados obtidos, o Setor de Metais Não-Ferrosos teve maior destaque ao apresentar a maior demanda adicional por gás natural e as maiores reduções em demanda de energia primária, emissões de CO2 e custo energético. Outros setores que se destacaram foram o Setor de Ferro e Aço e Setor de Alimentos e Bebidas. Tomando 2013 como ano-base, a demanda adicional por gás natural resultante da substituição de óleo combustível e eletricidade em processos térmicos representaria um aumento entre 37% a 42% na demanda de gás natural no setor industrial brasileiro, equivalente a 12% a 14% da oferta interna de gás natural no Brasil, ou ainda 35% a 40% da capacidade máxima do Gasbol. O impacto em energia primária representaria uma redução de 1% a 2% da demanda de energia primária do setor industrial brasileiro. O impacto em emissões de CO2 representaria uma redução de 4% a 5% das emissões de CO2 associadas ao uso de energia do setor industrial brasileiro. O impacto em custo energético representaria uma redução de 2% a 4% dos custos energéticos associados a eletricidade e óleo combustível do setor industrial brasileiro. Assim, considera-se que existe uma oportunidade de inserção do gás natural no setor industrial brasileiro resultante da substituição de óleo combustível e eletricidade por gás natural em processos térmicos. De forma geral, seus impactos reduzem a demanda de energia primária, as emissões de CO2 e o custo energético. Entretanto, trata-se de uma iniciativa de economia de energia via substituição energética, desse modo, ressalta-se necessidade de se fomentar a eficiência energética, para todos os usos finais e tipos de energia final em uso, de modo a se obter um maior impacto em termos de redução no consumo de energia e mitigação de emissões, dois elementos importantes no debate atual sobre combate a mudanças climáticas. / The present energy use structure in the Brazilian industrial sector is a consequence of its historical context within the Brazilian energy sector. This historical background helps to explain some characteristics, like the intensive use of electricity in heating processes, the electrothermia, that lasts until today. The current natural gas production scenario in Brazil is promising, considering the Pre-Salt production, which signals an opportunity to apply this natural resource to final energy uses with higher value, such as final energy for industry. In this context was structured this dissertation, comprising a data analysis technique development and its application to evaluate the insertion of natural gas in the Brazilian industrial sector and its impacts. The developed data analysis technique is constituted by the assessment of four indicators: Additional Demand (DA); Impact on Primary Energy (IEP); Impact on Carbon Emissions (IEC) and Impact on Energy Cost (ICE). In the results obtained, the Non-Ferrous Metals Sector was more prominent as it presented the greater additional demand for natural gas and the largest reductions in primary energy demand, CO2 emissions and energy costs. Other sectors that stood out were the Iron and Steel Sector and the Food and Beverages Sector. Considering 2013 as the base year, the additional demand for natural gas resulting from the substitution of fuel oil and electricity in heating processes would represent a 37% to 42% increase in the demand for natural gas in the Brazilian industrial sector, equivalent to 12% to 14% of Brazil\'s domestic natural gas supply, or 35% to 40% of Gasbol\'s maximum capacity. The impact on primary energy would represent a reduction of 1% to 2% of the primary energy demand of the Brazilian industrial sector. The impact on CO2 emissions would represent a reduction of 4% to 5% of the CO2 emissions associated to energy use of the Brazilian industrial sector. The impact on energy cost would represent a reduction of 2% to 4% of the energy costs associated with electricity and fuel oil of the Brazilian industrial sector. Thus, it is considered that there is an opportunity for the insertion of natural gas in the Brazilian industrial sector resulting from the substitution of fuel oil and electricity by natural gas in thermal processes. Overall, the substitution impacts reduce primary energy demand, CO2 emissions and energy costs. However, this is an energy-saving initiative through energy substitution, being necessary to further promote energy efficiency, for all end uses and types of final energy in use, to multiply the impacts in terms of reducing energy consumption and mitigating emissions, two important elements in the current debate on combating climate change.
23

The phenotypic expansion and its boundaries / L'expansion phénotypique et ses limites

Berthelot, Geoffroy 12 November 2013 (has links)
Le développement futur des performances sportives est un sujet de mythe et de désaccord entre les experts. Un article, publié en 2004, a donné lieu à un vif débat dans le domaine universitaire [1]. Il suggère que les modèles linéaires peuvent être utilisés pour prédire -sur le long terme- la performance humaine dans les courses de sprint. Des arguments en faveur et en défaveur de cette méthodologie ont été avancés par différent scientifiques et d’autres travaux ont montré que le développement des performances est non linéaire au cours du siècle passé [2, 3]. Une autre étude a également souligné que la performance est liée au contexte économique et géopolitique [4]. Dans ce travail, nous avons étudié les frontières suivantes : le développement temporel des performances dans des disciplines Olympiques et non Olympiques, avec le vieillissement chez les humains et d’autres espèces (lévriers, pur sangs, souris). Nous avons également étudié le développement des performances d’un point de vue plus large en analysant la relation entre performance, durée devie et consommation d’énergie primaire. Nous montrons que tous ces dévelopments sont limitées dans le temps [5, 6, 7] et que les modèles linéaires introduits précédemment sont de mauvais prédicteurs des phénomènes biologiques et physiologiques étudiés. Trois facteurs principaux et directs de la performance sportive sont l’âge [8, 9], la technologie [10, 11] et les conditions climatiques (température) [12]. Cependant, toutes les évolutions observées sont liées au contexte international et à l’utilisation des énergies primaires, ce dernier étant un paramètre indirect du développement de la performance. Nous montrons que lorsque les indicateurs des performances physiologiques et sociétales -tels que la durée de vie et la densité de population- dépendent des énergies primaires, la source d’énergie, la compétitioninter-individuelle et la mobilité sont des paramètres favorisant la réalisation de trajectoires durables sur le long terme. Dans le cas contraire, la grande majorité (98,7%) des trajectoires étudiées atteint une densité de population égale à 0 avant 15 générations, en raison de la dégradation des conditions environnementales et un faible taux de mobilité. Ceci nous a conduit à considérer que, dans le contexte économique turbulent actuel et compte tenu de la crise énergétique à venir, les performances sociétales et physiques ne devraient pas croître continuellement. / The development of sport performances in the future is a subject of myth and disagreement among experts. In particular, an article in 2004 [1] gave rise to a lively debate in the academic field. It stated that linear models can be used to predict human performance in sprint races in a far future. As arguments favoring and opposing such methodology were discussed, other publications empirically showed that the past development of performances followed a non linear trend [2, 3]. Other works, while deeply exploring the conditions leading to world records, highlighted that performance is tied to the economical and geopolitical context [4]. Here we investigated the following human boundaries : development of performances withtime in Olympic and non-Olympic events, development of sport performances with aging among humans and others species (greyhounds, thoroughbreds, mice). Development of performances from a broader point of view (demography & lifespan) in a specific sub-system centered on primary energy were also investigated. We show that all these developments are limited with time [5, 6, 7] and that previously introduced linear models are poor predictors of biological and physiological phenomena. Three major and direct determinants of sport performance are age [8, 9], technology [10, 11] and climatic conditions (temperature) [12]. However, all observed developments are related to the international context including the efficient use of primary energies. This last parameter is a major indirect propeller of performance development. We show that when physiological and societal performance indicators such as lifespan and population density depend on primary energies, the energy source, competition and mobility are key parameters for achieving longterm sustainable trajectories. Otherwise, the vast majority (98.7%) of the studied trajectories reaches 0 before 15 generations, due to the consumption of fossil energy and a low mobility rate. This led us to consider that in the present turbulent economical context and given the upcoming energy crisis, societal and physical performances are not expected to grow continuously.
24

Influences from Building Energy Efficiency Refurbishment on a Regional District Heating System

Lidberg, Tina January 2018 (has links)
Improving energy performance of existing buildings is an important part in decreasing energy use and in turn reduce the greenhouse gas emissions caused by human activity and the primary energy use. To be able to evaluate how energy refurbishment influences the greenhouse gas emissions and the primary energy use a wider system perspective is needed that puts the building in its context. This thesis deals with energy refurbishment packages performed on multi-family buildings within district heated areas and how they influence greenhouse gas emissions and primary energy use when the district heating use is altered. A simulated building is used to evaluate several energy refurbishment packages. The results are used as input data for models of district heating systems to cost optimize the district heating production. The results from the cost optimization are used to evaluate the impact on greenhouse gas emissions and primary energy use. The results show a difference between measures that saves district heating without increasing the use of electricity and measures that increases the use of electricity while district heating is saved. For example, a building refurbishment package including only building envelope improvements saves the same amount of district heating as a package including only mechanical ventilation with heat recovery. Despite this, the emissions of greenhouse gases and the use of primary energy is to a greater extent reduced in the first package because the use of electricity remains unchanged. Comparing energy refurbishment packages performed on the same building, but within different district heating systems, show the importance of the design of the district heating system. Depending on the fuel types used and to which extent electricity is co-produced in the district heating system, the results of implementing the energy refurbishment packages vary. The largest reduction of greenhouse gases and primary energy use occurs when a refurbishment package is performed on a building in a district heating system with high share of biofuel and no electricity production. / Att förbättra energiprestanda hos befintliga byggnader är en viktig del i arbetet med att minska energianvändningen och i sin tur minska utsläpp av växthusgaser orsakade av mänsklig aktivitet samt att minska användningen av primärenergi. För att kunna utvärdera hur energieffektivisering av byggnader påverkar växthusgasutsläpp och primärenergianvändning behövs ett brett systemperspektiv som sätter byggnaden i sitt sammanhang. Denna avhandling handlar om hur paket av energieffektiviseringsåtgärder som utförs på flerfamiljshus inom fjärrvärmeuppvärmda områden påverkar växthusgasutsläpp och primärenergianvändning när fjärrvärmeanvändningen förändras. Resultaten visar på skillnader mellan åtgärder som sparar fjärrvärme utan att öka användningen av el och åtgärder som ökar användningen av el medan fjärrvärme sparas. Till exempel sparar ett energieffektiviseringspaket som endast omfattar byggnadsskalsförbättringar samma mängd fjärrvärme som ett paket som endast omfattar installation av mekanisk ventilation med värmeåtervinning. Trots detta minskar utsläppen av växthusgaser och användningen av primärenergi i större utsträckning i det första paketet på grund av att elanvändningen förblir oförändrad. Vikten av fjärrvärmesystemets utformning visas då en byggnad där olika energieffektiviseringspaket testats, flyttas runt till olika fjärrvärmesystem. Beroende på vilka bränsletyper som används och i vilken utsträckning som el produceras i fjärrvärmesystemet så varierar resultaten. Den största minskningen av växthusgaser uppstår när ett renoveringspaket utförs på en byggnad i ett fjärrvärmesystem med hög andel biobränsle och ingen elproduktion.
25

Energieffektiviseringsåtgärder på ett äldre flerbostadshus : En fallstudie av Allfarvägen 37–43, Borlänge / Energy efficiency measures on an older apartment building

Dhicisow, Mohamed Muse, Abdullahi Hasan, Mohamed January 2021 (has links)
Syftet med det här examenarbetet har varit att analysera ett flerbostadshus som redan har energieffektiviserats med vanliga energieffektiviseringsåtgärder för att ytterligare installera andra energiåtgärder som är lönsamma och kan minska den inköpta energin.Bygg- och fastighetssektorns står för ungefär 40% av energianvändningen i Sverige. En stor del av denna energianvändning går det att minska genom att utföra energieffektiviseringsåtgärder på befintliga byggnader. Sverige har ett miljömål som är att nå ett nettoutsläpp år 2045 och bostadssektorn har en stor potential för att underlätta att Sverige når sitt energimål. Vanliga energieffektiviseringsåtgärder i flerbostadshus är bland annat fasad- och vindisolering, fönsterbyte och att installera mer energieffektiva ventilationssystem och belysningar. Exempelhuset har redan fått vindisolering, fasadputsning, treglasfönster, energieffektiva LED-lampor och en ny undercentral. Detta har resulterat i en specifik energianvändning som låg på ca 108 kWh/m2 år 2020. I Sverige ligger den genomsnittliga specifika energianvändningen på flerbostadshus ca 134 kWh/m2. För att få ner den specifika energianvändningen ännu mer har fyra andra energieffektiviseringsåtgärder undersökts och analyserats med avseende på sina energibesparingspotentialer och lönsamheter. De valda åtgärderna är en solvärmeanläggning, en solcellanläggning, snålspolande armaturer och en spillvattenvärmeväxlare (Ekoflow). Den specifika energianvändningen har gått ner till 90 kWh/m2 efter dessa energibesparingsåtgärder har utförts. Det visade sig att de snålspolande armaturerna, solcellanläggningen och solvärmeanläggningen är lönsamma. Däremot visade resultatet att spillvärmeväxlaren (Ekoflow) inte är lönsam. Men genom att paketera alla åtgärder har det lyckats att uppfylla lönsamhetskravet och att få en gemensam internränta som är högre än kalkylräntan. Kalkylräntan antas vara 5 % och internräntan har beräknats 6,45 %.Lönsamheten är förstås beroende på framtida energipriser såsom fjärrvärme-och elpriser. På energimarknaden kostar en kWh el ca 1,82 kr och en kWh värme ca 0,847 kr för konsumenter. Med hjälp av annuitetskalkyl har kostnaden för en kWh som alstras genom solvärmeanläggning och solcellanläggningen beräknats. För solvärme kostar 0,75 kr/kWh och för solel kostar 1 kr/kWh. Detta är fast pris under 30 år, alltså under kalkyltiden och denna energi är billigare jämfört med energin på marknaden. / The purpose of this thesis was to analyse an apartment building that has already been implemented with standard energy efficiency measures to further install other energy efficiency measures that are profitable and can reduce the purchased energy.The building sector is responsible for about 40 percent of energy use in Sweden. A large part of this energy use can be reduced by installing energy efficiency measures on existing buildings. Sweden has an environmental goal which is to reach a net emission by 2045 and the building sector has great potential to facilitate for Sweden to reach its energy goal.Common energy efficiency measures for multi-family buildings include insulation of external walls and attic insulation, window replacement, installing more energy-efficient ventilation systems and upgrading the lighting system. The example house has already received an attic insulation, facade plastering, triple-glazed windows, energy-efficient LED lamps and a district heating substation. This has resulted in a specific energy use that was 108 kWh / m2 in 2020 and in Sweden the average specific energy use is 134 kWh / m2 in apartment buildings.To reduce more the specific energy use, 4 energy efficiency measures have been investigated to be able to assess their potential of energy use reduction and profitability. These measures are a solar heating system, a photovoltaic system, Energy-efficient taps, and a wastewater heat exchanger (Ekoflow). The specific energy consumption has decreased to 90 kWh / m2 after these energy saving measures have been implemented. It turned out that the Energy-efficient taps, the photovoltaic system, and the solar heating system are profitable and Ekoflow is not profitable. But by collecting all measures in a package, it has been succeeded to fulfil the profitability requirement and to obtain a common internal rate of return which is higher than the discount rate. The discount rate is assumed to be 5% and the internal rate of return has been calculated at 6.45%.Profitability is dependent on future energy prices such as district heating and electricity prices. The market price is one kWh of electricity about 1.82 SEK and one kWh of heat costs about 0.847 SEK. Using an annuity calculation, the cost for a kWh obtained through a solar heating system and the solar cell system has been calculated. For the solar collector is calculated 0.75 SEK / kWh, and for the photo voltaic become 1 SEK / kWh. It will be a fixed price during the calculation period which is 30 years, and that means that this energy is cheaper than the energy on the market.
26

Influences from Building Energy Efficiency Refurbishment on a Regional District Heating System

Lidberg, Tina January 2018 (has links)
Improving energy performance of existing buildings is an important part in decreasing energy use and in turn reduce the greenhouse gas emissions caused by human activity and the primary energy use. To be able to evaluate how energy refurbishment influences the greenhouse gas emissions and the primary energy use a wider system perspective is needed that puts the building in its context. This thesis deals with energy refurbishment packages performed on multi-family buildings within district heated areas and how they influence greenhouse gas emissions and primary energy use when the district heating use is altered. A simulated building is used to evaluate several energy refurbishment packages. The results are used as input data for models of district heating systems to cost optimize the district heating production. The results from the cost optimization are used to evaluate the impact on greenhouse gas emissions and primary energy use. The results show a difference between measures that saves district heating without increasing the use of electricity and measures that increases the use of electricity while district heating is saved. For example, a building refurbishment package including only building envelope improvements saves the same amount of district heating as a package including only mechanical ventilation with heat recovery. Despite this, the emissions of greenhouse gases and the use of primary energy is to a greater extent reduced in the first package because the use of electricity remains unchanged. Comparing energy refurbishment packages performed on the same building, but within different district heating systems, show the importance of the design of the district heating system. Depending on the fuel types used and to which extent electricity is co-produced in the district heating system, the results of implementing the energy refurbishment packages vary. The largest reduction of greenhouse gases and primary energy use occurs when a refurbishment package is performed on a building in a district heating system with high share of biofuel and no electricity production. / Att förbättra energiprestanda hos befintliga byggnader är en viktig del i arbetet med att minska energianvändningen och i sin tur minska utsläpp av växthusgaser orsakade av mänsklig aktivitet samt att minska användningen av primärenergi. För att kunna utvärdera hur energieffektivisering av byggnader påverkar växthusgasutsläpp och primärenergianvändning behövs ett brett systemperspektiv som sätter byggnaden i sitt sammanhang. Denna avhandling handlar om hur paket av energieffektiviseringsåtgärder som utförs på flerfamiljshus inom fjärrvärmeuppvärmda områden påverkar växthusgasutsläpp och primärenergianvändning när fjärrvärmeanvändningen förändras. Resultaten visar på skillnader mellan åtgärder som sparar fjärrvärme utan att öka användningen av el och åtgärder som ökar användningen av el medan fjärrvärme sparas. Till exempel sparar ett energieffektiviseringspaket som endast omfattar byggnadsskalsförbättringar samma mängd fjärrvärme som ett paket som endast omfattar installation av mekanisk ventilation med värmeåtervinning. Trots detta minskar utsläppen av växthusgaser och användningen av primärenergi i större utsträckning i det första paketet på grund av att elanvändningen förblir oförändrad. Vikten av fjärrvärmesystemets utformning visas då en byggnad där olika energieffektiviseringspaket testats, flyttas runt till olika fjärrvärmesystem. Beroende på vilka bränsletyper som används och i vilken utsträckning som el produceras i fjärrvärmesystemet så varierar resultaten. Den största minskningen av växthusgaser uppstår när ett renoveringspaket utförs på en byggnad i ett fjärrvärmesystem med hög andel biobränsle och ingen elproduktion.
27

Energy sector analysis and modeling – From primary to final energy

Praz, Bastien January 2012 (has links)
Climate change and energy supply limitation are growing concerns. Solving them requires strong implication from our societies and more and more stakeholders and scientists are therefore interested in energy scenarios publication. They indeed provide options to be investigated in order to set the future strategies to tackle these issues. It is within this context that The Shift Project has launched the Scenario project which main purposes are to clarify this specific prospective field and develop a pedagogical energy scenario modeling tool. The Master Thesis work presented in this report is the result of a six months internship in the company within the Scenario project team, and more particularly within the energy scenario modeling tool development team. Beside the energy demand and supply side of a scenario design stands the energy sector. The work focused on this aspect, which corresponds to all the industry and the energy flows standing in between primary energy resources and our final energy consumption. It can therefore be considered as the global conversion process of the energy, which encompasses conversion efficiencies, energy allocation and the different losses. This energy sector is of main concern when one is dealing with energy scenarios since it can contain many possibilities to be investigated in order to set up different variants. Getting a strong knowledge about the energy sector is then crucial. Nevertheless, the global conversion process between primary and final energy still remains a big black box for many of us and therefore prevents us to realize its role and the means that can be applied to explore even further the possible energy scenarios possibilities.    To counteract this observation, this thesis work was dedicated to analyze the energy sector at world scale by revealing its components and the main levers that could be used to shape the future energy system. This analysis was conducted via the system approach and lead to the development of a methodology to model the energy sector and develop a module in which cursors enable an end-user to generate a wide range of scenarios and explore different resources allocation options etc. This module is part of TSP’s energy scenario modeling tool together with a demand and a supply side modules. This work is intended to provide a clear vision of the energy sector and the key parameters that might be of main importance to initiate variants study for energy scenarios prospects, such as power efficiencies, energy mix or distribution losses.
28

Comparative life cycle assessment of organic building materials

Yossef, Delav, Hot, Dino January 2021 (has links)
The ever-increasing awareness of global warming has made the building industry startlooking for alternative building solutions in order to meet the changing demands. Thesechallenges have given rise to organization which aim to go further and construct moresustainable alternatives in the form of Ecovillages. This thesis is conducted in collaborationwith Bysjöstrans Ekoby and aims to investigate what type of organic alternatives exist andhow they perform in building elements.The study was carried out through a comparative LCA where a base case construction forboth roof and wall was established. Followed by comparing different organic materials toeach other and the base case materials in order to determine low-impact materials. The goalwas to replaces as many layers within the structure such as insulation, structure, roofcladding, façade, wind and vapor barrier.This was later followed by combing the materials together in order to identify whichalternative construction options would perform the best in regard to greenhouse gasemissions (CO2 eq kg) and primary energy use (MJ).The results of the study show that the performance or organic materials vary significantly.Whit a lot of materials being better but also worse than traditional materials. It showed thatfor internal wall and roof surface adding clay plater can reduce the GHG emission with 68%, timber frame with 98 %, façade with 43 %, roof cladding with 93 %, vapor barrier with76 % and insulation with 79 %. The best preforming construction option could reduce thebase case emission with 68 %.
29

Effects of Energy Performance Improving Measures on a 1990's Brick House in Southern Czech Republic : Computer Simulations using IDA-ICE

Panek, Vaclav January 2023 (has links)
The residential sector was responsible for 25% of the Final Energy Demand (FED) in the European Union in 2015. Countries in Central and Eastern Europe such as the Czech Republic are particularly concerned with ensuring security of supply at the lowest possible cost in recent years. FED for space heating still corresponds to the largest fraction of the total FED in the residential sector in the Czech Republic. The vast majority of buildings constructed in 1990- 2000 do not comply with current standards for thermal protection and owners often rely on their own financial means when attempting to improve the overall Energy Performance (EP) of buildings. The goal(s) associated with renovation- or refurbishment measures must be defined to clarify the extent of work and consequently minimize investments. The aim of this thesis, a case study, was to use a whole building energy simulation program (IDA-ICE) to get insight into the potential of different retrofitting measures (represented by scenarios) to improve EP of a single-family summer house located in the South Bohemian Region of the Czech Republic. One of the simulated scenarios was the owner ́s suggestion to replace windows and entrance doors. The goal was to reduce FED for space heating to ≤50 kWh.m-2 floor area and year and by doing so attaining the status of a low-energy building. Simultaneously, reduced FED for space heating was supposed to be achieved without compromising air quality and should involve only the most efficient refurbishment measures to minimize the overall work. The scope was strictly limited to EP improving measures without consideration of mechanical ventilation or modification of the currently used space heating system. It was concluded that the owner's suggestion to merely replace windows and entrance doors would be an insufficient solution. SC-4 (i.e. the combined effect of windows and entrance doors replacement and the ground-floor insulation) and SC-5 (i.e. the combined effect of ground-floor insulation and the insulation of external walls and the roof) were deemed to represent the most optimal solutions from the simulated EP improving measures. The goal was achieved in both, i.e. 46.8 kWh.m-2 floor area and year in SC-4 and 44.3 kWh.m- 2 floor area and year in SC-5. Averages of zone air temperatures in selected zones were found to be more stable in SC-4, however, SC-5 performed better when comparing averages of CO2 concentration-values in selected zones on the first floor. Nevertheless, averages of relative humidity and CO2 concentration-values in all simulated scenarios were within the acceptable range of 35-60% and about 520 to 1000 ppm respectively (except for Bedroom 2 zone).
30

Entwicklung eines Doppelkolbenmotors – Konzept, Simulation und Prüfstandversuche

Diwisch, Pascal, Billenstein, Daniel, Rieg, Frank, Alber-Laukant, Bettina 10 December 2016 (has links) (PDF)
Aus der Einleitung: "Durch die Verwendung von Kraft-Wärme-Kopplung (KWK) kann sowohl die erzeugte elektrische als auch die anfallende thermische Energie genutzt und somit der Nutzungsgrad der eingesetzten Primärenergie deutlich gesteigert werden. Dieses Konzept wird sowohl in Blockheizkraftwerken (BHKW) wie auch in Range Extendern (RE) verwendet (Ferrari et al. 2012). Die bisher geringe Reichweite von Elektrofahrzeugen wird durch die zusätzlich vom RE bereitgestellte elektrische Energie erweitert. ..."

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