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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.
81

An Integrated Approach to Climate Change, Income Distribution, Employment, and Economic Growth*

Taylor, Lance, Rezai, Armon, Foley, Duncan K. 03 1900 (has links) (PDF)
A demand-driven growth model involving capital accumulation and the dynamics of greenhouse gas (GHG) concentration is set up to examine macroeconomic issues raised by global warming, e.g. effects on output and employment of rising levels of GHG; offsets by mitigation; relationships among energy use and labor productivity, income distribution, and growth; the economic significance of the Jevons and other paradoxes; sustainable consumption and possible reductions in employment; and sources of instability and cyclicality implicit in the twodimensional dynamical system. The emphasis is on the combination of biophysical limits and Post- Keynesian growth theory and the qualitative patterns of system adjustment and the dynamics that emerge. / Series: Ecological Economic Papers
82

Avaliação e otimização de pré-tratamentos e hidrólise enzimática do bagaço de cana-de-açúcar para a produção de etanol de segunda geração / Evaluation and optimization of pretreatments and enzymatic hydrolysis of the sugarcane bagasse for second generation ethanol production

Rabelo, Sarita Cândida 16 August 2018 (has links)
Orientadores: Aline Carvalho da Costa, Rubens Maciel Filho / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-16T02:15:39Z (GMT). No. of bitstreams: 1 Rabelo_SaritaCandida_D.pdf: 8964196 bytes, checksum: 4597e91fb6bb8979fe59578161b88ac3 (MD5) Previous issue date: 2010 / Resumo: O grande desafio para a produção de etanol de segunda geração consiste em determinar a melhor opção de disponibilizar a glicose a partir da hidrólise da celulose em termos de custo global, rendimento glicosídico e fermentabilidade do hidrolisado. Neste trabalho o objetivo foi estudar a produção de etanol de segunda geração a partir do bagaço de cana-de-açúcar. Foram abordadas a otimização e comparação de dois pré-tratamentos (hidróxido de cálcio e peróxido de hidrogênio alcalino), a otimização da carga enzimática na etapa de hidrólise e a fermentação do hidrolisado para a obtenção do etanol. Foram ainda feitas propostas para utilização dos resíduos do processo, principalmente o licor de pré-tratamento, o resíduo de hidrólise e a lignina residual precipitada. Os resultados mostram que os pré-tratamentos são efetivos para melhorar o ataque enzimático durante a etapa de hidrólise. Após otimização desta etapa foi possível obter rendimentos de globais de 51,78% e 83,41% para os pré-tratamentos com hidróxido de cálcio e peróxido de hidrogênio alcalino, respectivamente. Em relação à etapa de otimização enzimática, foi possível converter 90,8% e 100,0% da celulose presente no material pré-tratado com hidróxido de cálcio e peróxido de hidrogênio alcalino, com carga enzimática de 50,0 FPU/g biomassa seca pré-tratada e 25,0 CBU/g biomassa seca pré-tratada e 3,5 FPU/g biomassa seca pré-tratada e 25,0 CBU/g biomassa seca pré-tratada, respectivamente. Os hidrolisados obtidos para cada pré-tratamento não apresentaram qualquer problema em relação à fermentabilidade, obtendo-se rendimentos em etanol próximos ao estequiométrico. Estudos avaliando a produção de biogás a partir dos licores de pré-tratamento e resíduos de hidrólise mostraram que é possível conseguir bons rendimentos para os dois pré-tratamentos, sendo produzidos, na melhor condição, 180,09 ± 6,08 Nem3 de metano/g DQO para o licor de pré-tratamento com hidróxido de cálcio e 126,58 ± 8,78 Nem3 de metano/g DQO para o licor de pré-tratamento com peróxido de hidrogênio alcalino. Em relação ao resíduo de hidrólise, foram produzidos 171,51 ± 8,72 Nem3 de metano/g DQO para o resíduo do bagaço pré-tratado com hidróxido de cálcio e 165,52 ± 6,14 Nem3 de metano/g DQO para o resíduo do bagaço pré-tratado com peróxido de hidrogênio alcalino. A lignina obtida após precipitação ácida nos licores de pré-tratamento apresentou, após análise térmica, uma entalpia superior para o bagaço pré-tratado com hidróxido de cálcio em comparação ao bagaço pré-tratado com peróxido, sendo de 67,9 J/g e 52,5 J/g, respectivamente. Desta forma, além da lignina, a utilização do biogás se toma uma complementação energética importante para o processo produtivo do etanol de segunda geração / Abstract: The great challenge for second generation ethanol production is the determination of the best option to render glucose available through hydrolysis of cellulose in terms of overall cost, glucose yield and fermentability of the hydrolysate. In this work the objective was to study the production of second generation ethanol from sugarcane bagasse. The topics considered included the optimization and comparison of two pretreatments (calcium hydroxide and alkaline hydrogen peroxide), the optimization of the enzymatic load in the hydrolysis step and at the fermentation of the hydrolysate for ethanol production. Also, proposals were made for the use of the process residues, especially the pretreatment liquor, the hydrolysis residue and the precipitated residual lignin. The results show that the pretreatments are effective in improving enzymatic attack during the hydrolysis step. After optimization, it was possible to obtain cellulose yields of 51.78% and 83.41% for the pretreatments with calcium hydroxide and alkaline hydrogen peroxide, respectively. After optimization of the enzymatic load it was possible to convert 90.8% and 100.0% of cellulose in the pretreated material with calcium hydroxide and alkaline hydrogen peroxide, using enzymes loading of 50.0 FPU/g dry pretreated biomass and 25.0 CBU/g dry pretreated biomass and 3.5 FPU/g dry pretreated biomass and 25.0 CBU/g dry pretreated biomass, respectively. The hydrolysates obtained in each pretreatment did not have any fermentability difficulties, leading to ethanol yields close to the stoichiometric. Studies evaluating biogas production from the pretreatment liquor and hydrolysis residues have shown that it is possible to achieve good yields for the two pretreatments, with 180.09 ± 6.08 Ncm3 of methane/g COD for the pretreatment liquor with calcium hydroxide and 126.58 ± 8.78 Ncm3 of methane/g COD for the pretreatment liquor with alkaline hydrogen peroxide being produced in the best conditions. When the hydrolysis residue was considered 171.51 ± 8.72 Ncm3 of methane/g COD for the bagasse pretreated residue with calcium hydroxide and 165.52 ± 6.14 Ncm of methane/g COD for the bagasse pretreated residue with alkaline hydrogen peroxide were produced. The lignin obtained after acid precipitation in the pretreatments liquor showed, after thermal analysis, a higher enthalpy for bagasse pretreated with calcium hydroxide compared to bagasse pretreated with peroxide, of 67.9 J/g and 52.5 J/g, respectively. Thus, in addition to the lignin, the use of biogas energy can become an important complement to the second generation ethanol production / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química
83

Aplicação de um sistema de refrigeração com fluido secundário e termoacumulação em câmara de congelados / Application of a cooling system with secondary fluid and cool storage for a cold chamber

Freitas, Samuel Scarassatti 03 February 2012 (has links)
Orientador: Vivaldo Silveira Júnior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-19T16:38:58Z (GMT). No. of bitstreams: 1 Freitas_SamuelScarassatti_M.pdf: 3413897 bytes, checksum: 5e01dabc6101fefebe4dd9a0e9e103c1 (MD5) Previous issue date: 2012 / Resumo: Dentro da indústria, os equipamentos de refrigeração ocupam um destacado papel no que se refere ao consumo de energia elétrica. A tarifação deste insumo vem sofrendo freqüentes reajustes, na medida em que sua demanda cresce e atende as necessidades econômicas do país. Os sistemas de termoacumulação representam uma alternativa para a economia do consumo energético nos períodos de maior tarifação, o que tende a atenuar os gastos com a energia elétrica. Neste trabalho, foi proposta a construção de um sistema de termoacumulação, com o objetivo de comparar esta técnica com um sistema tradicional de expansão seca em termos de consumo e demanda energética. O estudo envolveu a montagem da derivação da linha de refrigeração, a partir de um chiller, até o evaporador de uma câmara frigorífica, onde foram instalados sensores de temperatura, pressão e vazão, permitindo a avaliação das condições do processo por expansão seca. Em paralelo, foi montada uma linha de escoamento para o fluido refrigerante secundário que interligou um circuito onde o fluido é resfriado pelo sistema de refrigeração, termoacumulado em um tanque e bombeado ate um trocador de calor instalado dentro da câmara, onde é utilizado para resfriar o ambiente. A aplicação da termoacumulação objetivou alcançar as mesmas condições da câmara, mantidas pela expansão seca, com a posterior avaliação do consumo energético apresentado pelos dois sistemas. Foram instalados sensores de temperatura na linha de refrigerante secundário e também dentro da câmara. O consumo de potência da bomba e do compressor foram registrados e utilizados na comparação energética dos sistemas. A avaliação qualitativa englobou o cálculo da carga térmica empírica da câmara, bem como o registro das condições de funcionamento dos sistemas durante a expansão seca e a refrigeração do circuito secundário. A comparação dos sistemas frente ao consumo energético indicou uma economia superior a 42% na utilização da termoacumulação durante o período de ponta em comparação com o sistema de expansão seca. A aplicação da termoacumulação manteve a temperatura do interior da câmara estável durante as três horas em que o compressor permaneceu desligado, mostrando ser uma técnica de grande economia energética quando comparada com o sistema secundário sem termoacumulação, apresentando uma economia de 26% nos gastos em função deste período / Abstract: In the industry, refrigeration equipments possess a detached function in electric energy consumption. The price of this input has been frequently adjusted. In the same way that the demand grows and fills the economic needs of the country. the cool storage systems represent an alternative for save power consumption during periods of peak pricing, tending to decrease spending on energy consumption. In this paper, it was proposed the construction of a system for cool storage, in order to compare that technique with a traditional dry-expansion system, in terms of consumption and energy. The study involved the derivation of the assembly line cooling from a chiller evaporator until a cold chamber, on the line, temperature, pressure and flow sensors, were installed allowing the evaluation of process conditions for dry expansion . In parallel, a line was built, through which the refrigerant is pumped through a secondary circuit where it is cooled by the cooling system, stored in a tank at low temperature, and pumped to a heat exchanger installed inside the chamber where it is used to cool the environment. . The cool storage application had as an objective maintains the room conditions as the same in dry expansion, With the subsequent evaluation of the energy consumption of each system. Temperature sensors were installed in the secondary coolant line and also inside the chamber. The power consumption of the pump and compressor were recorded and used to comparing the two systems. The evaluation, has included the empirical calculation of the heat load for the cold chamber and the recording data of the system operating conditions during the dry-expansion and the cooling by the secondary circuit The comparison between the systems has indicated energy savings of more than 42% in the use of the cool stored system during the peak period. The application of cool storage kept the temperature inside the camera steady during the three hours when the compressor was off, proving to be a technique of great energy savings when compared to the secondary system without termoacumulação, showing a 26% saving in costs due this period / Mestrado / Engenharia de Alimentos / Mestre em Engenharia de Alimentos
84

Práticas de gestão do uso da energia e sua relação com o desempenho sustentável no setor mineral brasileiro / Energy management practices and it's relation with the sustainable performance in the brasilian mineral sector

Perlin, Ana Paula 07 March 2016 (has links)
Fundação de Amparo a Pesquisa no Estado do Rio Grande do Sul / Energy is an essential commodity for the existence of industrial activities, however the lack of management of energy use can lead to numerous environmental, economic and social. Thus industries as energy-intensive play an essential role in the search of the preservation of the energy system. This study aimed to analyze the energy use management practices and its relationship to sustainable performance in the industries of the Brazilian mineral sector. Energy use management practices were measured by the model proposed by Liu et al. (2012). Next, the sustainable performance was identified from the performance indicators developed by the Global Reporting Initiative - GRI (2006, 2010b, 2014). The study is characterized as quantitative and was conducted from conducting a survey research with industries linked to the Brazilian Mining Institute. It was found that the practices regarding the use of existing energy management in companies are related to periodic verification of the impacts of their activities on the environment and encouraging daily energy-saving practices. By contrast the energy use management practices still not widespread in companies are adopting the ISO 50001 and the existence of an Internal Commission for Energy Conservation (CICE). Overall, from the analyzes performed it can be seen that there are positive associations between factors related to energy use management practices and sustainable performance. Thus, it was identified that management practices of energy use involving the integration of energy efficiency in organizations and monitoring of energy use management relate directly to the performance of enterprises, in social, economic and environmental terms. / A energia é um bem essencial para a existência das atividades industriais, no entanto a ausência de uma gestão do uso da energia pode levar a inúmeros impactos ambientais, econômicos e sociais. Assim, as indústrias, como grandes consumidoras de energia, exercem um papel essencial na busca da preservação do sistema energético. Este estudo teve como objetivo analisar as práticas de gestão do uso da energia e sua relação com o desempenho sustentável nas indústrias do setor mineral brasileiro. As práticas de gestão do uso da energia foram mensuradas por meio do modelo proposto por Liu et al. (2012). A seguir, o desempenho sustentável foi identificado a partir dos indicadores de desempenho desenvolvidos pelo Global Reporting Initiative - GRI (2006, 2010b, 2014). O estudo caracteriza-se como quantitativo e foi conduzido a partir da realização de uma pesquisa survey com as indústrias vinculadas ao Instituto Brasileiro de Mineração. Verificou-se que as práticas relacionadas à gestão do uso da energia existentes nas empresas estão relacionadas à verificação periódica dos impactos causados por suas atividades no meio ambiente e o incentivo às práticas diárias de economia de energia. Em contrapartida, as práticas de gestão do uso da energia, ainda pouco disseminadas nas empresas, são a adoção da ISO 50001 e a existência de uma Comissão Interna de Conservação de Energia (CICE). De forma geral, a partir das análises efetuadas, pode-se constatar a existência de associações positivas entre os fatores relacionados às práticas de gestão do uso da energia e o desempenho sustentável. Desse modo, identificou-se que práticas de gestão do uso da energia envolvendo a integração da eficiência energética nas organizações e o monitoramento da gestão do uso da energia relacionam-se diretamente ao desempenho das empresas, em termos sociais, econômicos e ambientais.
85

En byggnads energiprestanda : En utredande och jämförande studie av Boverkets författningssamling BEN1

Arnfelt, Emma January 2017 (has links)
This report is an exploratory and comparative study of Boverkets constitution BEN1. In this study the constitution BEN1 is examined, why the constitution was established, when is it applicable and what advantages and disadvantages will come with it. Today the housing and service sector is using a major part of Europe’s final energy use, in addition to this, these sectors also represents a major part of the total carbon dioxide emissions. The EU-commission aims to reduce the housing and service sectors energy use and emissions. In 2002 the European parliament established directives and demands for buildings energy performance. These directives were changed in 2009-2010, which led to an inspection of the already existing Swedish constitution, this was found to be inadequate by the EU-commission. Sweden decided to create a new constitution in order to satisfy EU’s new directives and demands. The focus is on a normal usage of the building in a normal year in the new constitution, BEN1.  The reader should receive an idea and understanding about BEN1 and why it was established in this report. Beyond this, the study will show the changes that happen to a buildings energy performance after the constitution is applied and what advantages and disadvantages this could bring.  This study was performed by simulating the buildings energy use with the input from BEN1 in a simulation tool, IDA Indoor Climate and Energy.  The study shows that the energy performance will change but it also shows that further studies should be made in order to obtain a more carefully drawn and common conclusion. / Detta är ett examensarbete på grundnivå (kandidatexamen), 15 högskolepoäng. Examensarbetet är en utredande och jämförande studie av Boverkets senaste författningssamling BEN1. I denna studie utreds BEN1, varför det upprättades, när det ska tillämpas och vad det medför i fråga om för- och nackdelar.   Idag utgör tjänste- och bostadssektorn en stor del av Europas slutliga energianvändning och totala koldioxidutsläpp, något som EU-kommissionen har som mål att minska. Minskningen skulle ske med tillämpning av Europaparlamentets direktiv och krav gällande energideklarationer som kom år 2002. Direktivet omarbetades under 2009-2010 vilket ledde till en granskning av det befintliga svenska regelverket, EU-kommissionen fann detta bristfälligt och beslutade därför om ett överträdelseförfarande. Sverige svarade på överträdelseförfarandet med den nya författningssamlingen BEN1 som handlar om fastställande av byggnaders energianvändning vid normalt brukande och ett normalår.  I denna rapport ska läsaren få en uppfattning om och förståelse kring Boverkets författningssamling BEN1 och varför den upprättats. Utöver det ska studien påvisa förändringarna som sker hos en byggnads energiprestanda vid tillämpning av BEN1 samt upplysa läsaren om vilka för- och nackdelar tillämpningen av BEN1 kan ge. Studien har utförts genom att simulera byggnadernas energianvändning, enligt BEN1s föreskrifter och allmänna råd, i IDA Indoor Climate and Energy, ett simuleringsverktyg. Studien visar att en byggnads energiprestanda kommer att förändras men att vidare studier bör göras för att en mer noggrann och allmän slutsats ska kunna erhållas. De största förändringarna gällande energiprestandan har skett i byggnadens behov av värme och varmvattenberedning, detta efter tillämpande av de schablonvärden BEN1 erhåller. Resultaten som erhålls i denna studie är enligt BEN1 validerade värden för byggnadernas energiprestanda.
86

Demolish or Refurbish an Existing Building? : A bachelor thesis on the climate impact of different methods of renewing a building

Lennermark, Desirée, Bjellerup, Victoria, Bäckström, Lisa, Wedman, Lisen January 2020 (has links)
The purpose of this bachelor thesis is to evaluate different alternatives of renewal regarding an already existing building. The case study building is located in the Ulleråker area in Uppsala, Sweden and is an old mental hospital building from the 1950’s which Uppsala Municipality wishes to restore as part of a bigger investment in the neighborhood. The different alternatives that will be investigated are refurbishment, with different insulation thickness, and a complete demolition and reconstruction of a new building with either wood or concrete. Carbon dioxide emissions connected to buildings will be calculated and analyzed as two elements, one being embodied carbon dioxide, and one being energy usage. Other aspects of interest, the economy and cultural values of the area, will be discussed. To estimate the amount of CO2 emissions, several life cycle assessments will be executed through the software One Click LCA (2015). Calculations will be done by hand in order to estimate the energy usage. Information and data are partly obtained from Uppsala Municipality, partly from literature and available resources. The results show that each option has a different advantage, the refurbishment resulting in considerably lower embodied carbon (114 kg CO2e/m2) but higher energy usage (95 kWh/m2 per year) as compared to the new concrete construction with larger amount of embodied carbon (279 kg CO2e/m2) but lower energy usage (44 kWh/m2 per year). This leads to a conclusion showing that a deep refurbishment is the best option regarding both embodied carbon and energy usage.
87

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.
88

Návrh energetických systémů využívajících vodík jako palivo / Design of Energy Systems Using Hydrogen as Fuel

Slováček, Adam January 2013 (has links)
Purpose of this thesis is wisdom accumulation from current area of energetic use of hydrogen and future systems. In overview is presented possible processes where dominate steam methane reforming. In main part of thesis, steam methane reforming will be analyzed and electrolysis also. Actual results will be discussed. Next part is about energetic use of hydrogen based on thermochemical properties and safety. Used of hydrogen will be divided to areas thermal generation as burner‘s section, electric generation as fuel cell‘s section, mechanical energy as combustion engine’s section and finally chemical transportation of energy. At the end will be made a promising energy systems using hydrogen as fuel which can be applied in a large scale.
89

Ansätze zur Betriebsdauerverlängerung von Suzlon Windkraftanlagen

Brökel, Jan January 2016 (has links)
Hintergrund "Die ersten in Serie produzierten und kommerziell relevanten Windkraftanlagen (WKA) wurden in den frühen 1990er Jahren aufgestellt. In Deutschland, wie auch in anderen Ländern, wurden in dieser Zeit Förderprogramme wie das Stromeinspeisegesetz aufgelegt und ein zügiger Ausbau der Windenergienutzung setzte ein. So wurden zu Beginn der 1990er Jahre ca. 200 Anlagen mit je bis zu 300 kW pro Jahr installiert und Ende der 1990er Jahre waren es schon bis zu 1500 Anlagen pro Jahr mit je mehr als 1500 kW Leistung. In den 2000ern stieg die Durchschnittsleitung der jährlich installierten Anlagen auf über 2 MW auch wenn sich die Anzahl der Installationen verringerte, siehe Abbildung 1 bei Ender (Ender 2015). Insgesamt sind ca. 3000 Altanlagen entweder schon ca. 20 Jahre im Betrieb und haben damit ihre Konstruktionslebenszeit erreicht oder sind kurz davor. Wie in Abbildung 1 bei Ender (Ender 2015) deutlich zu sehen, steht damit ein rapider Anstieg der von Abriss oder Weiterbetrieb betroffenen Anlagen in den nächsten 5 Jahren bevor. ..."
90

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 %).

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