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Bawaneh, Khaled. "Industrial facility nonprocess energy life cycle information." Diss., Wichita State University, 2011. http://hdl.handle.net/10057/5131.
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In this study, published information on nonprocess energy use, which includes lighting, heating, cooling, ventilation, humidity control, and particulate control, for industrial buildings has been analyzed and compiled and then represented in power intensity (W/ft2). More than thirty different sources of data related to industrial building energy use (covering about 82 buildings) were identified and analyzed. The overall objective of this research is to establish benchmark representative ranges (minimum, mean, medium, maximum) of nonprocess energy consumed by an industrial facility. That information will be used in life cycles of industrial products. The industrial manufacturing buildings were classified into six categories according to nonprocess energy use.
This research also investigated the climate zones influence on nonprocess energy use in industrial buildings. The hypothesis tested in this research is: if an industrial building has a characteristic nonprocess energy related to physical dimensions and desired comfort level, then using cooling degrees day (CDD) and heating degrees day (HDD) factors can normalize the measured nonprocess temperature control data for the climate zone differences. The mean, median, standard deviation and total nonprocess energies for current and zone-adjusted nonprocess energy for each facility in this study were calculated.
Finally, five industrial facilities were visited and the energy data for these facilities were collected. The nonprocess power intensity for the various nonprocess energy uses was calculated for each facility, based on the actual facility energy bills and measurements. Four separate analysis techniques were used to estimate the nonprocess energy for these facilities as a means to critically understand this information.Thesis (Ph.D.)--Wichita State University, College of Engineering, Dept. of Industrial and Manufacturing Engineering
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Huang, Shu-Wei Ph D. Massachusetts Institute of Technology. "High-energy sub-cycle optical waveform synthesizer." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/75634.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 147-157).
Over the last decade, the control of atomic-scale electronic motion by optical fields strong enough to mitigate the atomic Coulomb potential, has broken tremendous new ground with the advent of phase controlled high-energy few-cycle pulse sources. In particular, broadband optical parametric chirped pulse amplifier (OPCPA) has been investigated intensively in recent years to enable studies of novel strong-field physics phenomena such as high-harmonic generation (HHG) and strong-field ionization. Further investigation and control of these physical processes ask for the capability of waveform shaping on sub-cycle time scales, which requires a fully phase-controlled multiple-octave-spanning spectrum. To date, no single laser source can support a bandwidth of more than an octave. Coherent synthesis of pulses with different spectra, or wavelength multiplexing, presents a route towards obtaining a multi-octave spanning laser spectrum. The benefit of this approach lies in its modular design and scalability in both bandwidth and pulse energy. However, it was only recently laser scientists were able to successfully demonstrate coherent synthesis of two lasers albeit at low energy and high repetition rate. Achieving high pulse energy requires synthesis of low repetition rate pulses, which is a challenge because of the environmental perturbations typifying high-energy amplifiers. The technological advancements towards the ideal source for study and control of such strong-field physics are the focus of this thesis. The background reviews on femtosecond Ti:sapphire oscillators, carrier-envelope phase stabilization, chirped pulse amplifier, broadband OPCPAs, and HHG are given in Chapter 1. Chapter 2 starts with a discussion on the various properties of OPCPA which lends itself to the ideal building module for high-energy pulse synthesis. Then it is followed by a comprehensive optimization study and experimental results of broadband OPCPAs at different spectral ranges. In chapter 3, the first high-energy sub-cycle waveform synthesizer is presented. It is the prototype of a class of novel optical tools for atto-second control of strong-field physics experiments. Novel technologies that enable such a waveform synthesizer are described in details. At the end of the chapter, work towards the construction of a large-scale waveform synthesizer is included. Finally, the thesis is concluded by introducing some possible future directions.
by Shu-Wei Huang.
Ph.D.
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Bouchouireb, Hamza. "Advancing the life cycle energy optimisation methodology." Licentiate thesis, KTH, VinnExcellence Center for ECO2 Vehicle design, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-265556.
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The Life Cycle Energy Optimisation (LCEO) methodology aims at finding a design solution that uses a minimum amount of cumulative energy demand over the different phases of the vehicle's life cycle, while complying with a set of functional constraints. This effectively balances trade-offs, and therewith avoids sub-optimal shifting between the energy demand for the cradle-to-production of materials, operation of the vehicle, and end-of-life phases. This work further develops the LCEO methodology and expands its scope through three main methodological contributions which, for illustrative purposes, were applied to a vehicle sub-system design case study. An End-Of-Life (EOL) model, based on the substitution with a correction factor method, is included to estimate the energy credits and burdens that originate from EOL vehicle processing. Multiple recycling scenarios with different levels of assumed induced recyclate material property degradation were built, and their impact on the LCEO methodology's outcomes was compared to that of scenarios based on landfilling and incineration with energy recovery. The results show that the inclusion of EOL modelling in the LCEO methodology can alter material use patterns and significantly effect the life cycle energy of the optimal designs. Furthermore, the previous model is expanded to enable holistic vehicle product system design with the LCEO methodology. The constrained optimisation of a vehicle sub-system, and the design of a subset of the processes which are applied to it during its life cycle, are simultaneously optimised for a minimal product system life cycle energy. In particular, a subset of the EOL processes' parameters are considered as continuous design variables with associated barrier functions that control their feasibility. The results show that the LCEO methodology can be used to find an optimal design along with its associated ideal synthetic EOL scenario. Moreover, the ability of the method to identify the underlying mechanisms enabling the optimal solution's trade-offs is further demonstrated. Finally, the functional scope of the methodology is expanded through the inclusion of shape-related variables and aerodynamic drag estimations. Here, vehicle curvature is taken into account in the LCEO methodology through its impact on the aerodynamic drag and therewith its related operational energy demand. In turn, aerodynamic drag is considered through the estimation of the drag coefficient of a vehicle body shape using computational fluid dynamics simulations. The aforementioned coefficient is further used to estimate the energy required by the vehicle to overcome aerodynamic drag. The results demonstrate the ability of the LCEO methodology to capitalise on the underlying functional alignment of the structural and aerodynamic requirements, as well as the need for an allocation strategy for the aerodynamic drag energy within the context of vehicle sub-system redesign. Overall, these methodological developments contributed to the exploration of the ability of the LCEO methodology to handle life cycle and functional trade-offs to achieve life cycle energy optimal vehicle designs.Livscykelenergioptimerings-metodologin (LCEO) syftar till att hitta en designlösning som använder en minimal mängd av energi ackumulerat över de olika faserna av en produkts (i detta arbete i formen av ett fordon) livscykel, samtidigt som den uppfyller en förutbestämd uppsättning funktionella begränsningar. Genom detta kan avvägningar balanseras effektivt, och därmed undviks suboptimala förskjutningar mellan energibehovet för vagga-till-produktion av material, fordonets användningsfas samt hantering av det uttjänta fordonet, på engelska kallad End-Of-Life (EOL). Detta arbete vidareutvecklar LCEO-metodologin och utvidgar dess omfattning genom tre huvudsakliga metodologiska bidrag, som, för illustrativa syften, har applicerats på en fallstudie av ett fordons sub-systemdesign. En EOL-modell baserad på substitution med korrigeringsfaktorer, är inkluderad för att uppskatta energikrediter och bördor som härrör från hanteringen av det uttjänta fordonet. Flera olika scenarier som beskriver återvinning med olika nivåer av antagen degradering av egenskaper hos de återvunna materialen har definierats, och deras respektive LCEO utfall har jämförts med motsvarande resultat för scenarier baserade på deponering och förbränning med energiåtervinning. Resultaten visar att införandet av en EOL-modell i LCEO-metodologin kan ändra flöden och mönster kring materialanvändning och har en signifikant påverkan på den totala livscykelenergin i de optimala fordonsdesignen Då valet av EOL-modell har signifikans för LCEO utfallet, har de föregående, statiska modellerna kompletterats med en utvidgning mot en mer holistisk systemstudie utifrån LCEO. I denna utvidgning studeras frågor kring optimerade produktsystem, framförallt avseende en delmängd av EOL processernas parametrar som har inkluderats i form av kontinuerliga designvariabler med antagna barriärfunktioner som modellerar deras genomförbarhet. Resultaten visar att LCEO kan användas för att finna den optimala designen av en fordonskomponent tillsammans med dess associerade, ideala, syntetiska EOL-scenario. Dessutom demonstreras metodens förmåga att identifiera de underliggande mekanismer som möjliggör den optimala lösningens avvägningar. För att utöka komplexiteten i de ansatta funktionella begränsningarna har även form-relaterade variabler och aerodynamiska motståndsberäkningar tagits med. I det här fallet används krökningen på den studerade fordonskomponenten som ytterligare en variabel i LCEO analyser, med dess inverkan på det aerodynamiska motståndet och i och med detta variationer i användningsfasens energibehov. I detta fallet har det aerodynamiska motståndet tagits med i analysen genom uppskattning av motståndskoefficienten av en fordonskomponent framtagen genom strömningsmekaniska beräkningar. Denna uppskattning används sedan för att modellera den energi som krävs av fordonet för att övervinna det aerodynamiska luftmotståndet. I detta sammanhang visas också på behovet av en strategi för allokering av den aerodynamiska motståndsenergin hos en sub-komponent i relation till helheten, när fokus ligger på design av ett sub-system hos ett fordon. Resultaten visar att LCEO beskriver den underliggande funktionella synergin mellan de ansatta strukturella och de aerodynamiska kraven. Detta arbete bidrar till att LCEO utvecklas i flera olika avseenden som utgör väsentliga steg mot en pro-aktiv metod som kan hantera livscykel- och funktionella avvägningar i en optimal fordonsdesign ur ett livscykelenergiperspektiv.
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Lohse, Tim. "Life cycle assessment of a plus-energy house." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-266478.
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Purpose: This study analyses the environmental impacts of a plus-energy house. Such buildings produce more energy in their use-phase than they consume, by generating energy with photovoltaic cells and saving energy via extensive insulation. The entire life cycle of the building is investigated form cradle to grave. The research focuses on the identification of environmental hotspots and the break-even time, after which the avoided burdens from the energy surplus even out the environmental impacts. Method: To answer the research questions, an ISO 14040 compliant environmental impact assessment (LCA) was conducted. It covers the raw material extraction, production and manufacturing of the building, the energy consumption by the inhabitants, the demolition and subsequent waste processing as well as the energy generation from the photovoltaic cells during 50 years lifetime. The life cycle impact assessment method was based on EN 15804 with seven impact categories: global warming potential, depletion potential of the stratospheric ozone, acidification potential of soil and water, eutrophication potential, formation potential of tropospheric ozone, abiotic depletion potential for non-fossil resources, and abiotic depletion potential for fossil resources. Results: The use-phase with energy generation and consumption dominates in all the impact categories except for the stratospheric ozone depletion potential. Photovoltaic cell production has the largest impact in terms of resource and ozone depletion. The building does not set off its impacts with its avoided burdens during its lifetime. The break-even time is calculated for each impact category and starts at 654 years for global warming potential. The geometric standard deviation is calculated for every process, so that a Monte-Carlo simulation can be run. This makes it possible to calculate the standard deviation of the results. Discussion: It is possible to enhance the environmental performance of the building by focusing on the hotspots. A sensitivity analysis shows that enhancing the energy surplus during the use-phase would be the most effective measure. This could be achieved by increasing the photovoltaic cell area or decreasing the energy consumption.
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Hau, Jorge Luis. "Integrating life cycle assessment, energy and emergy analysis." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1407139681.
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Gastelum, Zepeda Leonardo. "Life Cycle Assessment of a Wave Energy Converter." Thesis, KTH, Industriell ekologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-206486.
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Renewable energies had accomplish to become part of a new era in the energy development area, making people able to stop relying on fossil fuels. Nevertheless the environmental impacts of these new energy sources also require to be quantified in order to review how many benefits these new technologies have for the environment. In this project the use of a Life Cycle Assessment (LCA) will be implemented in order to quantify the environmental impact of wave energy, an LCA is a technique for assessing various aspects with the development of a product and its potential impact throughout a product’s life (ISO 14040, 1997). Several renewables have been assessed for their environmental impact using this tool (wind power, biofuels, photovoltaic panels, among others). This project will be focused on the study of wave power, specifically devices called point absorbers.At the beginning this thesis offers a description of the Life Cycle Assessment methodology with a brief explanation of each steps and requirements according to the ISO 14000 Standard. Later a description of different wave energy technologies is explained, along with the classification of different devices depending on its location and its form of harvesting energy. After explaining the different types available at the moment, the thesis will focus on the point absorber device and explain an approach that can be taken in order to simplify the complexity of the whole system.Once the device is fully explained the thesis approaches the methodology pursued in order to evaluate the system in terms of environmental impact in the selected category, for this case global warming. After, an evaluation of the different modules from the wave energy converter in terms of its environmental impact and choosing the best conditions in order to reduce it has being done.At the end of the thesis an economical overview of building wave energy converters is considered among its monetized cost to the environment and a comparison of this new technologies among other renewables in the market is done, in order to have an overview of the potential this type of energy can have.The main research question to be answered by this master thesis is how competitive is wave energy among other renewable technologies available at the moment. Since at the moment wave energy is in its early stages a representation of how other renewables had advanced from its early stages until today is presented, and the potential of this type of energy is evaluated in environmental and economic figures showing competitive results that can further be improved.
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Jones, Craig I. "Life cycle energy consumption and environmental burdens associated with energy technologies and buildings." Thesis, University of Bath, 2011. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.532723.
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This portfolio of published research contains nine papers and assesses the life cycle environmental burdens of energy technologies and buildings. Several analytical tools were used but these all fall under the umbrella of environmental life cycle assessment (LCA), and include energy analysis, carbon appraisal and the consideration of other environmental issues. The life cycle of all products starts with an assessment of embodied impacts. The current author has completed significant research on the embodied carbon of materials. This includes the creation of a leading embodied carbon database (the ICE database) for materials which has been downloaded by over 10,000 professionals and has made a significant contribution to knowledge. This portfolio of work includes analysis on methods for recycling in embodied impact assessment and LCA. This is an influential topic and therefore appears in two of the publications. The ICE database was applied by the current author to over 40 domestic building case studies and an embodied carbon model for buildings was created from these. The latter was used to provide benchmark values for six types of new houses in the UK.The portfolio of work then progresses to full LCA of energy systems. LCA is used to assess the embodied impacts versus operational impacts of 11 kV electrical cables. In this case embodied impacts were not significant and preference should be given to reducing electrical losses in the cables. The tool of LCA was then applied to a national electricity network. It revealed that Lebanon had a particularly poor centralised electricity network that was both unreliable and unsustainable with high impacts in all environmental categories. The final paper in this portfolio is on Building Integrated PV (BIPV) and brings together all aspects of the current author’s work and knowledge. It considers embodied burdens, electricity generation and BIPV can replace roofing materials.
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Colpan, Can Ozgur. "Exergy Analysis Of Combined Cycle Cogeneration Systems." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12605993/index.pdf.
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In this thesis, several configurations of combined cycle cogeneration systems proposed by the author and an existing system, the Bilkent Combined Cycle Cogeneration Plant, are investigated by energy, exergy and thermoeconomic analyses. In each of these configurations, varying steam demand is considered rather than fixed steam demand. Basic thermodynamic properties of the systems are determined by energy analysis utilizing main operation conditions. Exergy destructions within the system and exergy losses to environment are investigated to determine thermodynamic inefficiencies in the system and to assist in guiding future improvements in the plant. Among the different approaches for thermoeconomic analysis in literature, SPECO method is applied. Since the systems have more than one product (process steam and electrical power), systems are divided into several subsystems and cost balances are applied together with the auxiliary equations. Hence, cost of each product is calculated. Comparison of the configurations in terms of performance assessment parameters and costs per unit of exergy are also given in this thesis.
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Davidsson, Simon. "Life Cycle Exergy Analysis of Wind Energy Systems : Assessing and improving life cycle analysis methodology." Thesis, Uppsala universitet, Globala energisystem, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-157185.
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Wind power capacity is currently growing fast around the world. At the same time different forms of life cycle analysis are becoming common for measuring the environmental impact of wind energy systems. This thesis identifies several problems with current methods for assessing the environmental impact of wind energy and suggests improvements that will make these assessments more robust. The use of the exergy concept combined with life cycle analysis has been proposed by several researchers over the years. One method that has been described theoretically is life cycle exergy analysis (LCEA). In this thesis, the method of LCEA is evaluated and further developed from earlier theoretical definitions. Both benefits and drawbacks with using exergy based life cycle analysis are found. For some applications the use of exergy can solve many of the issues with current life cycle analysis methods, while other problems still remain. The method of life cycle exergy analysis is used to evaluate the sustainability of an existing wind turbine. The wind turbine assessed appears to be sustainable in the way that it gives back many times more exergy than it uses during the life cycle.
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Roux, Charlotte. "The life cycle performance of energy using household products." Thesis, Norwegian University of Science and Technology, Department of Energy and Process Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11012.
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The number of household gadgets that use energy, usually electricity, has multiplied in recent decades and energy use in a category that was long called other has risen significantly. In the mean time, another concern has arisen: the carbon cost related to the production and disposal of the gadgets. Investigating household electric and electronic equipment (EEE) as a specific household consumption category, the objective of this project is to get more understanding of their consumption and of their carbon footprint over there life-cycle. Space and water heating as well as lighting are excluded. The focus is on Norwegian household carbon footprint considering its specificities both in terms of consumption patterns, external trade and energy mix. First, an economic and statistical analysis of product ownership is conducted. It uses several data sources, such as the recent REMODECE campaign, sales data, lifetime estimation, EE-register data (registration of input and output of Electric and electronic equipment on the Norwegian market) and data from statistical office of Norway. Second, the project aims to record, analyze and compare different sources of information considering production and end-of-life. Both bottom up and top down approaches are investigated, even if a stress is put on bottom-up studies, such as ongoing European EuP study with its Ecoreport tool and EcoInvent database. Third it gives a best estimate of EEEs share in household carbon footprint, found to be 8,1% at 1,5 tons of CO2equivalent per household with production phase as a main contributor. A discussion on uncertainties assessing precision and identifying information gaps is also conducted. In addition to facilitate further research by setting up a framework grouping information sources critically analyzed, this project highlights the increasing importance of EEE products regarding sustainable consumption by putting numbers on the table.
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Trujillo, Iliana Cardenes. "Quantifying the energy consumption of the water use cycle." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:df481801-cce1-4824-986c-612f4673b8eb.
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The management and delivery of water and wastewater consume significant amounts of energy, mostly in the form of electricity. With increasing populations, climate change, water quality issues and increasing energy prices, it is more important than ever to understand energy consumption patterns. Energy usually represents the largest operational cost in water utilities around the world, yet there is limited work aiming to quantify the specific relationship between water and its associated energy, and understand its implications for future decision-making. This thesis presents variousmethodological approachesto quantify and understand energy use in water infrastructure systems, as well as how to incorporate them in decision-making processes. The main hypotheses are as follows: firstly, a detailed understanding of the use of energy in water infrastructure systems can facilitate more efficient and sustainable water infrastructure systems and, secondly, that incorporating energy into planning for water and wastewater resources can help understand the impacts of decisions and establish trade-offs between actions. To test these hypotheses, the thesis presents an analytical approach to various areas. Firstly, it identifies, maps and quantifies the energy consumption patterns within a water infrastructure system. This is then used to identify inefficiencies and areas of potential energy saving. Secondly, it incorporates detailed energy costs into short and long-term water resources management and planning. Thirdly, it evaluates trade-offs between energy costs and changing effluent quality regulations in wastewater resources. The Thames River basin, in the south-east of England, is used as a case study to illustrate the approach. The results demonstrate that a systematic approach to the quantification of energy use in a water infrastructure system can identify areas of inefficiencies that can be used to make decisions with regards to infrastructure planning. For example, water systems have significant geo-spatial variations in energy consumption patterns that can be addressed specifically to reduce negative trade-offs. The results also show that incorporating detailed energy information into long-term water resources planning can alter the choices made in water supply options, by providing more complete information. Furthermore, methodologically, they show how several methodological approaches can be used to support more complete decision-making in water utilities to reduce short and long-term costs. In this particular case study, the results show that there are important differences in energy consumption by region, and significant differences in the seasonal and energy patterns of water infrastructure systems. For example, water treatment was shown to be the largest consumer of energy within the whole system, compared with pumping or wastewater treatment; but wastewater treatment energy consumption was shown to be the fastest growing over time due to changes in water quality regulatory frameworks. The results show that more stringent effluent standards could result in at least a doubling of electricity consumption and an increase of between 1.29 and 2.30 additional million tonnes of CO2 a year from treating wastewater in large works in the UK. These are projected to continue to increase if the decarbonisation of the electricity grid does not occur fast enough. Finally, the thesis also shows that daily energy consumption can be reduced by up to 18% by optimally routing water through a water network. optimization of water networks, and that a change in discount rates could change the daily operating costs by 19%, that in turn leads to a resulting different set of optimal investment options in a water supply network.
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Cox, Jennifer Marie. "Analysis of a tubular solid oxide fuel cell topping cycle with a modified rankine bottoming cycle." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/17531.
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Gormez, Mehmet A. "DRIVING CYCLE OPTIMIZATION OF AN ELECTRIC CITY BUS NETWORK." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron153357330257683.
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Huang, Ran. "Exact Thermodynamic Calculation of a Monatomic System and Its Ideal Glass Transition on a New Recursive Lattice Formed by Cubic Units." University of Akron / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=akron1239653703.
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Fay, Mark Roger. "Comparative life cycle energy studies of typical Australian suburban dwellings /." Connect to thesis, 1999. http://eprints.unimelb.edu.au/archive/00000382.
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HERRERIA, ERNESTO JAVIER RUANO. "SIMULATION OF AN ORGANIC RANKINE CYCLE POWERED BY SOLAR ENERGY." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2012. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=21796@1.
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FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIROEsta simulação considera um ciclo Rankine que utiliza um fluido de trabalho orgânico, com a particularidade que a fonte de energia de entrada ao sistema será solar. Esta energia renovável que provem do potencial do Sol é aproveitada com a utilização de coletores concentradores lineares parabólicos. Estes dois circuitos: do ciclo Rankine orgânico e do conjunto de coletores interatuam termicamente mediante um trocador de calor chamado de gerador de vapor. Adicionalmente, existe um sistema de armazenamento térmico que permite acumular parte da energia solar coletada para ser utilizada em períodos sem radiação solar ou com níveis baixos da mesma. A primeira parte deste trabalho mostra os aspectos teóricos introdutórios e as considerações para trabalhar com um ciclo Rankine de tipo orgânico, o tipo de coletores escolhido e a utilização de armazenamento térmico. O segundo capítulo mostra o modelo matemático apropriado para simular um sistema de geração de potência de baixa capacidade (50 kW) e os componentes de cada circuito: ciclo (bomba, expansor, condensador, recuperador, gerador de vapor), coletores (cobertura, refletor, absorvedor, etc.) e armazenamento (tanques, etc.). A simulação foi desenvolvida no software EES. O terceiro analisa os parâmetros do modelo, seus possíveis valores físicos, a sensibilidade da sua variação e sua seleção adequada com o objetivo de efetuar uma simulação bastante similar à realidade e as incertezas presentes. No capítulo final se apresentam os resultados em base as condições de desenho consideradas.
This simulation considers a Rankine cycle that works with an organic fluid, but has the particularity of using solar power as the font of input energy. This renewable energy that comes from the sun’s potential is taken with the use of parabolic trough collectors. These two circuits: that of the organic Rankine cycle (ORC) and the other of collector’s ensemble interact termically in a heat exchanger called as vapor generator. Adicionally there’s a thermal storage system that allows accumulating part of the collected solar energy to be used for periods of time when there’s no solar radiation or with very low levels of it. The first part of this work shows the introductory theoretical aspects and the considerations to work with an organic Rankine cycle (ORC), the type of chosen collector and the use of heat storage. The second chapter shows the appropriate mathematic model to simulate a system of power generation of low capacity (50 kW) and the components of each circuit: ORC (pump, expander, condenser, recuperator, vapor generator), collectors (glass cover, reflector mirror, absorber tube, etc.) and thermal storage (storage tanks, etc.). The simulation was developed using EES software. The third chapter analyzes the parameters of the model, specially its values and possible variations to approach the simulation to the reality. In the final chapter, some results are presented based on some considered design conditions.
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Vinberg, Erik Magni. "Energy use in the operational cycle of passenger rail vehicles." Thesis, KTH, Spårfordon, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-234853.
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This master thesis investigates and analyzes the energy use for traction and auxiliary equipment in passenger rail vehicles. It covers both the train service with passengers and when the trains are going through other stages in the everyday operation. The operational cycle and associated operational situations are introduced as a way of describing the varying use of a train over time. The descriptions focus on the most common activities and situations, such as stabling and parking, regular cleaning, inspections and maintenance. Also how these situations affect energy use by their need for different auxiliary systems to be active. An energy model is developed based on the operational cycle as a primary input, together with relevant vehicle parameters and climate conditions. The latter proving to be a major influence on the energy used by the auxiliary equipment. The model is applied in two case studies, on SJ's X55 and Västtrafik's X61 trains. Both are modern electric multiple units equipped with energy meters. Model input is gathered from available technical documentation, previous studies and by measurements and parameter estimations. Operational cycle input is collected through different planning systems and rolling stock rosters. Climate input is finally compiled from open meteorological data banks. The results of the case studies show that the method and models are useful for studying the energy used by the trains in their operational cycles. With the possibility to distinguish the energy used by the auxiliary equipment, both during and outside the time the trains are in service with passengers. With this it's also possible to further investigate and study potential energy saving measures for the auxiliary equipment. Simulations of new ventilation control functions and improved use of existing operating modes on the trains show that considerable energy savings could be achieved with potentially very small investments or changes to the trains. The results generally show the importance of a continued investigation of the auxiliary equipment's energy use, as well as how the different operational situations other than the train service affect the total energy use.Detta examensarbete utreder och analyserar energianvändningen för passagerarjärnvägsfordons traktion- och hjälpkraftssystem, både under tågdriften med passagerare och andra delmoment som tågen genomgår under den normala dagliga driften. För detta introduceras driftcykeln och tillhörande driftsituationer som ett sätt att beskriva användningen av ett tåg över tiden. Syftet är att beskriva de vanligast förekommande aktiviteterna och situationerna, såsom uppställning och parkering, regelbundna inspektioner, klargörningar och underhåll. Även hur dessa situationer påverkar energianvändningen genom ett varierande behov av hjälpkraft och aktiva funktioner i tågen. En energimodell baserad på driftcykeln som huvudsaklig indata, tillsammans med tågets egenskaper samt det omgivande klimatet, tas fram. Klimatet visar sig vara en avgörande faktor i hjälpkraftens energianvändning. Modellen utvärderas i typstudier på SJs X55 och Västtrafiks X61. Båda är elektriska motorvagnståg utrustade med energimätare. Indata till modellen samlas in genom tillgänglig teknisk dokumentation, tidigare studier och genom mätningar samt parameterestimering. Driftcyklerna för tågtyperna sammanställs med hjälp av olika planeringssystem och omloppsplaner. Väder- och klimatdata samlas slutligen in från öppna databaser för metrologiska data. Resultaten från typstudierna visar att metoden och modellerna är användbara verktyg för att kunna beskriva tågens energianvändning i deras driftcykler. Med möjligheten att särskilja hjälpkraftssystemens energianvändning vid tågdriften med passagerare men även i de övriga situationerna. Med detta blir det också möjligt att undersöka potentiella energibesparingsåtgärder för hjälpkraftssystemen. Simulering av förbättrade styrfunktioner för ventilationen och förbättrat utnyttjade av redan inbygga energibesparande driftlägen på tågen visar att betydande energibesparingar kan fås med relativt små medel och få förändringar på fordonen. De sammantagna resultaten av arbetet visar på vikten av att fortsätta undersöka och utreda hjälpkraftens energianvändning samt hur driftsituationerna utanför tågdriften med passagerare påverkar den totala energianvändningen.
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Webber, Gordon Andrew. "A prototype energy management system for a solar powered cycle." Master's thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/5086.
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Shetye, Nitish. "Life-Cycle Energy Analysis of a High Strength Steel Application." Thesis, KTH, Lättkonstruktioner, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-290157.
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Steel is one of the most important engineering and construction material. It is used everywhere around us from making tiny nuts and bolts to massive cargo ships. It is a basic component in building societies and the development of mankind. The demand of steel is influenced by the population of the world and the per-capita consumption.
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Stephan, André. "Towards a comprehensive energy assessment of residential buildings: a multi-scale life cycle energy analysis framework." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209465.
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Buildings are directly responsible for 40% of the final energy use in most developed economies and for much more if indirect requirements are considered. This results in huge impacts which affect the environmental balance of our planet.However, most current building energy assessments focus solely on operational energy overlooking other energy uses such as embodied and transport energy. Embodied energy comprises the energy requirements for building materials production, construction and replacement. Transport energy represents the amount of energy required for the mobility of building users.
Decisions based on partial assessments might result in an increased energy demand during other life cycle stages or at different scales of the built environment. Recent studies have shown that embodied and transport energy demands often account for more than half of the total lifecycle energy demand of residential buildings. Current assessment tools and policies therefore overlook more than 50% of the life cycle energy use.
This thesis presents a comprehensive life cycle energy analysis framework for residential buildings. This framework takes into account energy requirements at the building scale, i.e. the embodied and operational energy demands, and at the city scale, i.e. the embodied energy of nearby infrastructures and the transport energy of its users. This framework is implemented through the development, verification and validation of an advanced software tool which allows the rapid analysis of the life cycle energy demand of residential buildings and districts. Two case studies, located in Brussels, Belgium and Melbourne, Australia, are used to investigate the potential of the developed framework.
Results show that each of the embodied, operational and transport energy requirements represent a significant share of the total energy requirements and associated greenhouse gas emissions of a residential building, over its useful life. The use of the developed tool will allow building designers, town planners and policy makers to reduce the energy demand and greenhouse gas emissions of residential buildings by selecting measures that result in overall savings. This will ultimately contribute to reducing the environmental impact of the built environment.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
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Petrovic, Bojana. "Life cycle assessment and life cycle cost analysis of a single-family house." Licentiate thesis, Högskolan i Gävle, Energisystem och byggnadsteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-36901.
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The building industry is responsible for 35% of final energy use and 38% of CO2 emissions at a global level. The European Union aims to reduce CO2 emissions in the building industry by up to 90% by the year 2050. Therefore, it is important to consider the environmental impacts buildings have. The purpose of this thesis was to investigate the environmental impacts and costs of a single-family house in Sweden. In the study, the life cycle assessment (LCA) and the life cycle cost (LCC) methods have been used by following the “cradle to grave” life cycle perspective. This study shows a significant reduction of global warming potential (GWP), primary energy (PE) use and costs when the lifespan of the house is shifted from 50 to 100 years. The findings illustrate a total decrease in LCA outcome, of GWP to 27% and PE to 18%. Considering the total LCC outcome, when the discount rate increases from 3% to 5% and then 7%, the total costs decrease significantly (60%, 85% to 95%). The embodied carbon, PE use and costs from the production stage/construction stage are significantly reduced, while the maintenance/replacement stage displays the opposite trend. Operational energy use, water consumption and end-of-life, however, remain largely unchanged. Furthermore, the findings emphasize the importance of using wood-based building materials due to its lower carbon-intensive manufacturing process compared to non-wood choices. The results of the LCA and LCC were systematically studied and are presented visually. Low carbon and cost-effective materials and installations have to be identified in the early stage of a building design so that the appropriate investment choices can be made that will reduce a building’s total environmental and economic impact in the long run. Findings from this thesis provide a greater understanding of the environmental and economic impacts that are relevant for decision-makers when building single-family houses.Byggbranschen svarar för 35% av den slutliga energianvändningen och 38 % av koldioxidutsläppen på global nivå. Europeiska unionen strävar efter att minska koldioxidutsläppen i byggnadsindustrin med upp till 90% fram till 2050. Därför är det viktigt att beakta byggnaders miljöpåverkan. Syftet med denna avhandling var att undersöka miljöpåverkan och kostnader för ett enfamiljshus i Sverige. I studien har livscykelbedömningen (LCA) och livscykelkostnadsmetoderna (LCC) använts genom att tillämpa livscykelperspektivet ”vagga till grav”. Studien visar en stor minskning av global uppvärmningspotential (GWP), användning av primärenergi (PE) och kostnader vid växling från 50 till 100 års husets livslängd. Resultaten visar en årlig minskning med 27% för utsläpp av växthusgaser och med 18% för användningen av primärenergi. Med tanke på det totala LCC-utfallet, när diskonteringsräntan ökar från 3%, 5% till 7%, minskar de totala kostnaderna avsevärt (60%, 85% till 95%). Det noteras att klimatavtrycket, primärenergianvändningen och kostnaderna från produktionssteget/konstruktionssteget minskar avsevärt, medan underhålls- / utbytessteget visar den motsatta trenden när man byter från 50 till 100 års livslängd. Den operativa energianvändningen, vattenförbrukningen och avfallshanteringen är fortfarande nästan samma när man ändrar livslängden. Vidare betonar resultaten vikten av att använda träbaserade byggmaterial på grund av lägre klimatpåverkan från tillverkningsprocessen jämfört med alternativen. LCA- och LCC-resultaten studerades systematiskt och redovisades visuellt. De koldioxidsnåla och kostnadseffektiva materialen och installationerna måste identifieras i ett tidigt skede av en byggnadskonstruktion genom att välja lämpliga investeringsval som kommer att minska de totala miljö och ekonomiska effekterna på lång sikt. Resultaten från denna avhandling ger ökad förståelse för miljömässiga och ekonomiska konsekvenser som är relevanta för beslutsfattare vid byggnation av ett enfamiljshus.
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Benelmir, Riad. "Second analysis of a cogeneration cycle." Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/20000.
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Jaconelli, Palm Kim. "An evaluation of sustainable designs for trucks : A life cycle analysis." Thesis, KTH, Kraft- och värmeteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-291115.
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The largest carbon footprint in the life cycle of a truck comes from the use phase. However, with new fuels and larger renewable energy share in the electricity mix, both the manufacture and the disposal phase show increasing weight in carbon emission. A truck consists in large part of steel, which in production generates carbon dioxide. Hydrogen Breakthrough Ironmaking Technology (HYBRIT), a joint project between SSAB, LKAB and Vattenfall is aimed at changing the Swedish steel production to become carbon neutral by switching from coke as the reducing agent to hydrogen in a direct reduction process. The aim of this project is to evaluate the environmental burden posed by a Scania truck. The thesis is on the metallic pathways in the manufacturing process, as well as different design technologies to determine the environmental impact in general and the specific carbon dioxide footprint for a truck. The main research question to be investigated is: How does the metallic pathways affect the environmental impact of a Scania truck? The objectives of this study are to determine: • how manufacturing with traditional steel affects the environmental impact and carbon footprint. • how manufacturing with carbon neutral steel (HYBRIT) affects the environmental impact and carbon footprint. • how the choice of drivetrain impacts on the sustainability aspects of the truck. The study encompasses a literature review and life cycle assessment (LCA) where four different truck manufacturing scenarios were modeled: the current situation, HYBRIT in Sweden with the energy carrier of today, HYBRIT in Sweden with renewable energy carriers and HYBRIT technology worldwide. Both cases with and without recycling are also studied. As results, the environmental impact from using traditional iron & steel making amounts to 15.6 ton CO2-eq per truck without recycling and 5.8 ton CO2-eq per truck with recycling. Implementing the HYBRIT technology in the Swedish pathway would reduce these numbers to 12.4 ± 0.4 ton CO2-eq and 2.7 ± 0.4 ton CO2-eq respectively. The use phase emissions are expected to continue to dominate the life cycle emissions and lightweight designs, although energy intensive in the manufacturing process, could have a positive contribution in reducing CO2 emission. The HYBRIT process could be a promising technology to mitigate some of the environmental burdens posed by trucks especially in combination with electrification of the drivetrain and an electric grid with a high renewable energy mix.De störta utsläppen under en lastbils livscykel kommer från användarfasen. Men med nya bränslen och en högre andel förnybar energi i elektricitetmixen så får tillverkningsfasen och återvinningsfasen en större betydelse gällande de totala utsläppen. En lastbil består till stor del av stål, vilket genererar koldioxid i dess tillverkning. Ett nytt projekt mellan SSAB, LKAB och Vattenfall kallat Hydrogen Breakthrough Ironmaking Technology (HYBRIT) har som mål att ställa om den svenska stålindustrin till att bli koldioxidneutral genom att ersätta koksen med vätgas i reduktionsprocessen. Målet med denna studie är att utvärdera den miljömässiga last som en Scanialastbil medför. Studien analyserar de metalliska tillverksbanor som finns tillgängliga och tittar på olika teknologiska designalternativ för att få en bild av miljöbelastningen och koldioxidavtrycket för en lastbil.Den huvudsakliga forskningsfrågan är: Hur påverkar de olika metalliska tillverksbanorna miljöbelastningen av en lastbil? Målen med denna studie är att fastställa: Hur tillverkningen med traditionellt stål påverkar miljöbelastningen och koldioxidavtrycket. • Hur tillverkningen med koldioxidneutralt stål (HYBRIT) påverkar miljöbelastningen och koldioxidavtrycket. • Hur påverkar drivlinan hållbarhetsaspekterna för en lastbil. Rapporten innehåller en litteraturanalys och en livscykelanalys där fyra olika lastbilstillverkningsscenarion modelleras: dagens situation, HYBRIT i Sverige med dagens energibärare, HYBRIT i Sverige med förnybara energibärare och HYBRIT teknologin i hela världen. Scenarierna analyseras med och utan återvinning. Studien fann att miljöbelastningen för dagens tillverkningsteknik var 15,6 ton CO2-eq per lastbil utan att ta hänsyn till återvinning och 5,8 ton CO2-eq per lastbil med återvinning. Implementering av HYBRIT teknologin i Sverige minskade utsläppen till 12.4 ± 0.4 ton CO2-eq utan återvinning och 2.7 ± 0.4 ton CO2-eq med återvinning. Användarfasen förväntas fortsätta dominera utsläppen och lättviktsdesigner kan ha en positiv inverkan på utsläppen. HYBRIT teknologin ses som lovande för att minska de totala utsläppen från en lastbil livscykel, särskilt i kombination med elektrifiering av drivlinan och en elektricitetmix med mycket förnybar energi.
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Molyneaux, Glenn Arthur. "Resorption cycle heat pump with ammonia-water working fluid." Thesis, University of Ulster, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326335.
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Dodoo, Ambrose. "Life cycle primary energy use and carbon emission of residential buildings." Doctoral thesis, Mittuniversitetet, Institutionen för teknik och hållbar utveckling, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-14942.
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In this thesis, the primary energy use and carbon emissions of residential buildings are studied using a system analysis methodology with a life cycle perspective. The analysis includes production, operation, retrofitting and end-of-life phases and encompasses the entire natural resource chain. The analysis focuses, in particular, on to the choice of building frame material; the energy savings potential of building thermal mass; the choice of energy supply systems and their interactions with different energy-efficiency measures, including ventilation heat recovery systems; and the effectiveness of current energy-efficiency standards to reduce energy use in buildings. The results show that a wood-frame building has a lower primary energy balance than a concrete-frame alternative. This result is primarily due to the lower production primary energy use and greater bioenergy recovery benefits of wood-frame buildings. Hour-by-hour dynamic modeling of building mass configuration shows that the energy savings due to the benefit of thermal mass are minimal within the Nordic climate but varies with climatic location and the energy efficiency of the building. A concrete-frame building has slightly lower space heating demand than a wood-frame alternative, because of the benefit of thermal mass. However, the production and end-of-life advantages of using wood framing materials outweigh the energy saving benefits of thermal mass with concrete framing materials. A system-wide analysis of the implications of different building energy-efficiency standards indicates that improved standards greatly reduce final energy use for heating. Nevertheless, a passive house standard building with electric heating may not perform better than a conventional building with district heating, from a primary energy perspective. Wood-frame passive house buildings with energy-efficient heat supply systems reduce life cycle primary energy use. An important complementary strategy to reduce primary energy use in the building sector is energy efficiency improvement of existing buildings, as the rate of addition of new buildings to the building stock is low. Different energy efficiency retrofit measures for buildings are studied, focusing on the energy demand and supply sides, as well as their interactions. The results show that significantly greater life cycle primary energy reduction is achieved when an electric resistance heated building is retrofitted than when a district heated building is retrofitted. For district heated buildings, the primary energy savings of energy efficiency measures depend on the characteristics of the heat production system and the type of energy efficiency measures. Ventilation heat recovery (VHR) systems provide low primary energy savings where district heating is based largely on combined heat and power (CHP) production. VHR systems can produce substantial final energy reduction, but the primary energy benefit largely depends on the type of heat supply system, the amount of electricity used for VHR and the airtightness of buildings. Wood-framed buildings have substantially lower life cycle carbon emissions than concrete-framed buildings, even if the carbon benefit of post-use concrete management is included. The carbon sequestered by crushed concrete leads to a significant decrease in CO2 emission. However, CO2 emissions from fossil fuels used to crush the concrete significantly reduce the carbon benefits obtained from the increased carbonation due to crushing. Overall, the effect of carbonation of post-use concrete is small. The post-use energy recovery of wood and the recycling of reinforcing steel both provide higher carbon benefits than post-use carbonation. In summary, wood buildings with CHP-based district heating are an effective means of reducing primary energy use and carbon emission in the built environment.
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Zhang, Siduo. "Life cycle analysis of an integrated biogas-based agriculture energy system." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/43993.
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Large quantity of manure is generated in the livestock industry in British Columbia (BC) and natural
gas is being consumed intensively in BC’s agriculture sector. We proposed to integrate the livestock
farms and the greenhouses to promote waste-to-energy and waste-to-material exchanges following
the principles of Industrial Ecology (IE). Natural gas consumptions on farms are replaced by
renewable biogas generated from anaerobic digestion (AD) of farm wastes (mainly livestock manure).
CO₂ for plant enrichment in greenhouses is supplied by biogas combustion flue gases and the
residues (digestate) from digesters are used as animal bedding materials, plant growing media, and
liquid fertilizers. An integrated dairy farm and greenhouse was first modeled. Co-digestion of manure
with a variety of organic farm wastes was further evaluated with an aim to enhance the biogas
production. To address the problems of too much digestate surplus and high CO₂ demand for
greenhouse CO2 enrichment, the mushroom farm was further introduced into the integrated system.
In this way, the digestate surplus can be used as a growing media for growing mushrooms and the
CO₂–rich ventilation air from the mushroom can be directed to the greenhouse for CO₂ enrichment.
A Life Cycle Analysis (LCA) was conducted to quantify the environmental impacts of each of the
proposed cases in comparison to the conventional agriculture practices.
The LCA results showed that the integrated dairy farm-greenhouse system reduces non-renewable
energy consumption, climate change, acidification, respiratory effects from organic emissions, and
human toxicity by more than 50% compared to conventional operations; among which the reductions
in non-renewable energy consumption, climate change, and human toxicity are the most significant.
If the digestate surplus is treated as a waste, the integrated system has a ~20% increase in
eutrophication and respiratory effects from inorganic emissions. When other organic wastes are codigested
with dairy manure, all the impacts can be further reduced in all cases. If a mushroom farm is
introduced to form an integrated dairy farm-greenhouse-mushroom farm system, a large greenhouse
can be facilitated and the digestate can be largely reused; thus all the analyzed impacts are
significantly reduced compared to the base scenario.
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Hung, Christine. "Environmental Impacts of Renewable Energy : An Overview of Life Cycle Results." Thesis, Norwegian University of Science and Technology, Department of Energy and Process Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11014.
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Selected non-renewable and renewable energy processes from the ecoinvent 2.2 life cycle inventory database were analysed using basic contribution analysis, geometric series expansion, and structural path analysis. The hierarchical perspective of the ReCiPe impact assessment method was applied. The sources studied included biomass, wind, solar photovoltaic, hydropower, natural gas combined cycle and hard coal. Several technologies within each energy source were studied for comparison purposes. The processes were compared based on material consumption, land use and emissions for the production of 1 EJ (278 TWh). Results indicate that all of the renewable energy sources studied had a significantly lower impact than the non-renewable sources chosen. With the exception of bioenergies and pumped reservoir hydropower, technologies for the same energy source showed similar behaviour in the analyses performed.The findings from this study confirm previous work stating the environmental and human health superiority of renewable energy technologies over fossil fuel energy.
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Kiani, Mohamad Reza. "Life cycle energy consumption associated with glass within commercial building envelopes." Thesis, University of Brighton, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.479077.
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Better thermal performance of glass and glazed units together with advances in modern construction technologies has enabled designers to consider the use of higher proportions of glass in commercial building envelopes. A higher glazing percentage is typically lighter in envelope and building structure, and provides more daylight and solar heat to the interior during winter seasons. On the other hand, there is a potential of excessive solar heat gain during summer. The percentage of glass in the envelope influences the structural loads and consequently the embodied energy for the structure, foundation and envelope. It will also affect the operational energy and the potential for recycling. Review of the literature showed that previous research projects have evaluated the energy implication of individual stages of the life cycle, however to date none have attempted to aggregate the total life cycle energy consumption. A tool has been developed in order to evaluate the whole life cycle energy consumption associated with glass within commercial building envelopes based on the results obtained from structural analysis programme, thermal modelling software as well as gathered data. The tool enabled the analysis of the energy consumption related to manufacturing of envelope components, building structure and foundation, transp011ation, building operation (heating, cooling and lighting), and recycling associated with typical minimum and maximum envelope glazing areas representing a partially glazed (PG) and fully glazed (FG) envelopes with 35% and 90% double glazed units (DGUs). The overall results of life cycle energy analyses, with 25 years life expectancy for the envelope, showed that the life cycle energy consumption associated with glass within FG building can be up to 20% less compared with PG building. Manufacturing energy consumption associated with FG building showed to be up to 17% less compared to PG building due to less use of materials in building structure and foundation, and envelope. Operational energy analysis, within the context of current air-conditioned commercial buildings, indicated that FG building can consume up to 22% more heating and cooling, but 27% less lighting energy compared to PG. This highlighted that lighting energy can be as significant as heating and cooling energy consumption during the building operational period. Furthermore it was shown that manufacturing energy can be as high as 20% of the total heating and cooling energy consumption. Recycling energy analysis revealed there may not be energy saving by recycling glass into window glass especially for long transportation distances. In conclusion, it was shown that the current perception of fully glazed buildings consuming more operational energy than partially glazed buildings is dependent upon the properties of DGUs. In addition this research developed a methodology and a life cycle energy evaluation tool (with certain limitations) to address the key parameters affecting the associated energy consumption related to building envelopes. The tool can be used by building envelope designers to prioritise their designs and selection of materials to reduce the associated life cycle energy impacts. Furthermore suggestions are made for future development of design guidance to aid building envelope designers to easily choose a DGU at the early stages of design which results in the least building heating and cooling energy consumption.
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Johansson, Elin, and Filip Norrman. "Life cycle analysis on phase change materials for thermal energy storage." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264526.
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Sustainable energy sources and utilization is a large area of interest and the developments are moving fast. Recently, thermal energy storage in the form of phase change materials other than water have caught more interest and a need of analysis for the entire life cycle of the materials have appeared. Previous work in the area shows that health and safety aspects of the products’ life cycle have been neglected and comparisons between different phase change materials other than water are sparsely researched. The objectives for this report are to compare three different phase change material intended for thermal energy storage in a life cycle analysis point of view with both environmental and health and safety aspects. A screening process of materials was subsequently performed in order to find suited materials given the objective (Octadecane, Xylitol and Manganese Nitrate Hexahydrate), taking into consideration the relevance in the scientific community amongst other criteria. The life cycle is in this work bounded from cradle to grave without recycling and for a thermal energy storage heating system operating in Scandinavian climates assuming 52 cycles per year. The results indicate that Octadecane are preferable in terms of global warming potential over 100 years (ca 4.5 kg CO2/kg Octadecane produced) and Xylitol more preferable in terms of cumulative energy demand (ca 21.5 MJ per kg Xylitol produced) and energy payback time (1.17 years). The health and safety aspects are difficult to evaluate in terms of working conditions and ecotoxicity but a simple scale have been put to use to give an overview of the health risk associated with each material. In the health and safety aspects Xylitol also show the most promise but further development of a methodology for evaluating these terms are recommended.Hållbar energiteknik är ett omtalat och snabbt utvecklande område där fasomvandlandematerial för termisk energiförvaring har dragit till sig uppmärksamhet. På grund av denna uppmärksamhet har behovet för en fullständig livscykelanalys för de relevanta materialen uppkommit. Föregående rapporter och journaler om ämnet har visat brister i fokus på hälso- och säkerhetsaspekter och i jämförelse med andra fasomvandlandematerial än paraffiner och vatten. Målet med denna rapport är att utföra och jämföra livscykelanalyser för tre olika fasomvandlandematerial med både miljöaspekter och hälso- och säkerhetsaspekter. En urvalsprocess av intressanta material har därmed genomförts för att hitta lämpliga kandidater att undersöka (Oktadekan, Xylitol och Mangan nitrat hexahydrat), med avseende på bl.a. hur mycket materialen studerats inom termisk energiförvaring. Livscykeln inom denna rapport är bunden från Cradle-to-grave utan återvinning av material och opererar under skandinaviska förhållanden med 52 värmecykler per år. Resultaten indikerar att Oktadekan är mest lämpad för globaluppvärmnings potential över 100 år (ca 4,5 kg CO2/kg Oktadekan producerad) och Xylitol mest lämpad för kumulativt energikrav (ca 21,5 MJ per kg Xylitol producerad) samt återbetalningstid för energi (1,17 år). De hälso- och säkerhetsaspekterna är svåra att definiera inom arbetsförhållanden och ekotoxicitet men en enkel skala baserad på ’GHS hazard statements’ har etablerats för att få en överblick över materialens hälsorisk. Även här visade Xylitol vara mest lämpad men fortsatt utveckling av en metodik för att analysera dessa aspekter rekommenderas.
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Dong, Jun. "MSWs gasification with emphasis on energy, environment and life cycle assessment." Thesis, Ecole nationale des Mines d'Albi-Carmaux, 2016. http://www.theses.fr/2016EMAC0017/document.
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Récemment, la pyro-gazéification de déchets ménagers solides (DMS) a suscité une plus grande attention, en raison de ses bénéfices potentiels en matière d’émissions polluantes et d’efficacité énergique. Afin de développer un système de traitement de ces déchets, durable et intégré, ce manuscrit s’intéresse plus spécifiquement au développement de la technique de pyro-gazéification des DMS, à la fois sur l’aspect technologique (expérimentations) et sur son évaluation globale (modélisation). Pour cette étude, quatre composants principaux représentatifs des DMS (déchet alimentaire, papier, bois et plastique) ont été pyro-gazéifiés dans un lit fluidisé sous atmosphère N2, CO2 ou vapeur d’eau. Les expériences ont été menées avec les composés seuls ou en mélanges afin de comprendre les interactions mises en jeu et leurs impacts sur la qualité du syngas produit. La présence de plastique améliore significativement la quantité et la qualité du syngas (concentration de H2). La qualité du syngas est améliorée plus particulièrement en présence de vapeur d’eau, ou, dans une moindre mesure, en présence de CO2. Les résultats obtenus ont été ensuite intégrés dans un modèle prédictif de pyro-gazéification basé sur un réseau de neurones artificiels (ANN). Ce modèle prédictif s’avère efficace pour prédire les performances de pyro-gazéification des DMS, quelle que soit leur composition (provenance géographique). Pour améliorer la qualité du syngas et abaisser la température du traitement, la gazéification catalytique in-situ, en présence de CaO, a été menée. L’impact du débit de vapeur d’eau, du ratio massique d’oxyde de calcium, ainsi que de la température de réaction a été étudié en regard de la production (quantité et pourcentage molaire dans le gaz) d’hydrogène. La présence de CaO a permis d’abaisser de 100 oC la température de gazéification, à qualité de syngas équivalente. Pour envisager une application industrielle, l’activité du catalyseur a aussi été évaluée du point de vue de sa désactivation et régénération. Ainsi, les températures de carbonatation et de calcination de 650 oC et 800 oC permettent de prévenir la désactivation du catalyseur, tandis que l’hydratation sous vapeur d’eau permet la régénération. Ensuite, une étude a été dédiée à l’évaluation et à l’optimisation de la technologie de pyro-gazéification par la méthode d’analyse de cycle de vie (ACV). Le système de gazéification permet d’améliorer les indicateurs de performances environnementales comparativement à l’incinération conventionnelle. De plus, des systèmes combinant à la fois la transformation des déchets en vecteur énergétique et la mise en œuvre de ce vecteur ont été modélisés. La pyro-gazéification combinée à une turbine à gaz permettrait de maximiser l’efficacité énergétique et de diminuer l’impact environnemental du traitement. Ainsi, les résultats permettent d’optimiser les voies actuelles de valorisation énergétique, et de d’optimiser les techniques de pyro-gazéificationDue to the potential benefits in achieving lower environmental emissions and higher energy efficiency, municipal solid waste (MSW) pyro-gasification has gained increasing attentions in the last years. To develop such an integrated and sustainable MSW treatment system, this dissertation mainly focuses on developing MSW pyro-gasification technique, including both experimental-based technological investigation and assessment modeling. Four of the most typical MSW components (wood, paper, food waste and plastic) are pyro-gasified in a fluidized bed reactor under N2, steam or CO2 atmosphere. Single-component and multi-components mixture have been investigated to characterize interactions regarding the high-quality syngas production. The presence of plastic in MSW positively impacts the volume of gas produced as well as its H2 content. Steam clearly increased the syngas quality rather than the CO2 atmosphere. The data acquired have been further applied to establish an artificial neural network (ANN)-based pyro-gasification prediction model. Although MSW composition varies significantly due to geographic differences, the model is robust enough to predict MSW pyro-gasification performance with different waste sources. To further enhance syngas properties and reduce gasification temperature as optimization of pyro-gasification process, MSW steam catalytic gasification is studied using calcium oxide (CaO) as an in-situ catalyst. The influence of CaO addition, steam flowrate and reaction temperature on H2-rich gas production is also investigated. The catalytic gasification using CaO allows a decrease of more than 100 oC in the reaction operating temperature in order to reach the same syngas properties, as compared with non-catalyst high-temperature gasification. Besides, the catalyst activity (de-activation and re-generation mechanisms) is also evaluated in order to facilitate an industrial application. 650 oC and 800 oC are proven to be the most suitable temperature for carbonation and calcination respectively, while steam hydration is shown to be an effective CaO re-generation method. Afterwards, a systematic and comprehensive life cycle assessment (LCA) study is conducted. Environmental benefits have been achieved by MSW gasification compared with conventional incineration technology. Besides, pyrolysis and gasification processes coupled with various energy utilization cycles are also modeled, with a gasification-gas turbine cycle system exhibits the highest energy conversion efficiency and lowest environmental burden. The results are applied to optimize the current waste-to-energy route, and to develop better pyro-gasification techniques
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Kleut, Petar. "Recuperation of the exhaust gases energy using a Brayton cycle machine." Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/76807.
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Lately, car manufacturers have been put to a big challenge to reduce the CO2 emission of their entire fleets. Norms of pollutant emissions limit the ways to achieve the desired CO2 emission goals, as some of the solutions that would lead to lower CO2 emission also lead to higher pollutant emission. Waste Heat Recovery (WHR) could be a good solution to lower the CO2 emission of the Internal Combustion Engine (ICE) without increasing the pollutant emission. In the present thesis different WHR strategies are analysed and the results suggested it would be interesting to further study the Brayton cycle machine.
Air Brayton Cycle (ABC) represents a way to recover a part of the heat energy of the ICE exhaust gases and transform it into mechanical energy. Recovered mechanical energy would then be returned to the crankshaft of the ICE, thereby reducing the amount of energy that has to be liberated by combustion of fuel which lowers the fuel consumption and CO2 emission.
The study of ABC started with an analysis of the ideal cycle in order to obtain the theoretical maximum of the system. The study continued with an analysis of the semi ideal cycle where all losses are taken into account only by two efficiency coefficients. This analysis showed that for the diesel engine efficiency of the ABC is very low because of the low exhaust gas temperature. For the gasoline engine the cycle could be viable when the ICE is working under steady condition and higher load. These conditions could be fulfilled when the vehicle is driven on the highway.
Detailed analysis was aimed at determining the cycle main losses. They were determined to be: pumping losses, losses caused by heat transfer and mechanical losses. Taking into account these main losses along with other direct and indirect losses it was concluded that the cycle is not viable for the types of the WHR machines that were considered in this study.
In order for the cycle to be viable some other either existing or new machine type should be tested, that would lower the main losses and offer good isentropic and mechanical efficiency for desired conditions.Últimamente los fabricantes de automóviles se han puesto el gran reto de reducir la emisión de CO2 en la totalidad de sus flotas. Las nuevas normativas para la reducción de las emisiones contaminantes limitan los medios para lograr los objetivos deseados en la emisión de CO2 porque algunas de las soluciones que llevan a la reducción en la emisión de CO2 también dan lugar a un incremento en la emisión de otros contaminantes. La recuperación de calor residual (WHR) podría ser una buena solución para reducir las emisiones de CO2 del motor de combustión interna (ICE) sin poner en peligro la emisión de contaminantes. En la presente Tesis se analizaron diferentes estrategias de WHR y se concluyó que sería interesante estudiar más a fondo la máquina de ciclo Brayton. El Ciclo Brayton de Aire (ABC) permite recuperar una parte del calor de los gases de escape del ICE y transformar este calor en energía mecánica. La energía mecánica recuperada se devuelve al cigüeñal del ICE, reduciendo de ese modo la cantidad de energía que tiene que ser liberada por la combustión del combustible, lo cual permite reducir el consumo de combustible y las emisiones de CO2. En esta Tesis se estudia el ABC mediante un análisis del ciclo ideal con el fin de obtener el máximo teórico del sistema. El modelo se mejora con un análisis del ciclo semi-ideal donde se tienen en cuenta todas las pérdidas mediante el uso de dos coeficientes generales. Este análisis muestra que para el motor diesel la eficiencia del ciclo ABC es muy baja debido a la baja temperatura del gas de escape. Para el motor de gasolina el ciclo podría ser viable cuando el ICE está trabajando bajo condiciones estacionarias y una carga mayor. Estas condiciones se podrían cumplir cuando el vehículo está circulando en autopista. El análisis detallado de este ciclo tiene como objetivo determinar las pérdidas principales de ciclo. Las pérdidas principales se identificaron como: las pérdidas de bombeo, las pérdidas causadas por la transferencia de calor y las pérdidas mecánicas. Teniendo en cuenta estas pérdidas principales junto con otras pérdidas directas e indirectas, se concluyó que el ciclo no es viable para los tipos de máquinas WHR que fueron considerados en este estudio. Para que el ciclo sea viable se tiene que buscar alguna otra máquina existente o un nuevo tipo de máquina que reduzca las principales pérdidas y ofrezca un buen rendimiento isentrópico y mecánico para las condiciones deseadas.
Últimament els fabricants d'automòbils s'han posat el gran repte de reduir l'emissió de CO2 de la totalitat de les seues flotes. Les noves normatives de reducció de les emissions contaminants limiten els mitjans per assolir els objectius desitjats d'emissió de CO2 perquè algunes de les solucions que porten a la reducció en l'emissió de CO2 també donen lloc a un increment a l'emissió de altres contaminants. La recuperació de calor residual (WHR) podria ser una bona solució per reduir les emissions de CO2 del motor de combustió interna (ICE) sense posar en perill l'emissió de contaminants. En la present Tesi s'han analitzat diferents estratègies WHR i es va concloure que seria interessant estudiar més a fons el cicle Brayton. El Cicle Brayton d'Aire (ABC) representa una manera de recuperar una part de la calor dels gasos d'escapament de l'ICE i transformar calor a l'energia mecànica. L'energia mecànica recuperada es retorna al cigonyal de l'ICE reduint d'aquesta manera la quantitat d'energia que ha de ser alliberada per la combustió del combustible permitint la reducció del consum de combustible i les emissions de CO2. En aquesta Tesi s'ha començat estudiant un ABC amb una anàlisi del cicle ideal per tal d'obtenir el màxim teòric del sistema. Este model es millora amb una anàlisi del cicle semiideal on es tenen en compte totes les pèrdues amb tan sols dos coeficients d'eficiència. Aquesta anàlisi va mostrar que per al motor dièsel l'eficiència del cicle ABC és molt baixa a causa de la baixa temperatura del gas d'escapament. Per al motor de gasolina el cicle podria ser viable quan l'ICE està treballant sota condicions estacionàries i una càrrega més gran. Aquestes condicions es podrien complir quan el vehicle està circulant en autopista. L'anàlisi detallada del cicle va tenir com a objectiu determinar les pèrdues principals de cicle. Les pèrdues principals es van identificar com: les pèrdues de bombament, les pèrdues causades per la transferència de calor i les pèrdues mecàniques. Tenint en compte aquestes pèrdues principals juntament amb altres pèrdues directes i indirectes, es va concloure que el cicle no és viable per als tipus de màquines WHR que van ser considerats en aquest estudi. Perquè el cicle puga ser viable s'ha de buscar alguna altra màquina existent o un nou tipus de màquina que puga reduir les principals pèrdues i puga oferir un bon rendiment isentròpic i mecànic per a les condicions desitjades.
Kleut, P. (2016). Recuperation of the exhaust gases energy using a Brayton cycle machine [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/76807
TESIS
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Doyle, Tygue Stuart. "Decentralized power and heat derived from an eco-innovative integrated gasification fuel cell combined cycle." Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/12929.
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This research investigates the energy, financial and environmental performance of an innovative integrated gasification fuel cell combined cycle fuelled by municipal solid waste that includes hydrogen storage and electrolysis. The suitability for fuel cells to run on synthesis gas coming from the gasification of waste is determined by the sensitivity of the fuel cell to run on contaminated fuel. Out of the available fuel cell technologies solid oxide fuel cells (SOFCs), because of their ceramic construction and high operating temperatures, are best suited for syngas operation. Their high operating temperature ( > 650°C) and the presence of nickel at the anode means that it is possible to reform hydrocarbons to provide further hydrogen. A major contaminant to be considered in gasification systems is tar which can foul pipework and cause substantial performance losses to the plant. Experimental research on the effects of tar on a SOFC at varying concentrations and operating conditions show; that some carbon deposition serves to improve the performance of the fuel cell by reducing the ohmic resistance, and there is a tendency for the tar to reform which improves overall performance. These improvements are seen at moderate tar concentrations but at higher concentrations carbon deposition causes substantial performance degradation. Numerical simulations representing all aspects of the proposed system have been developed to understand the energy performance of the system as a whole as well as the financial and environmental benefits. Taking into account variations in the waste composition, and the wholesale electricity price the proposed system, scaled to process 100,000 tonnes of waste per year (40,000 removed for recycling), has a simple payback period of 7.2 years whilst providing CO2 savings of 13%. Over the year the proposed system will provide enough electricity to supply more than 23,000 homes and enough heat for more than 5,800 homes (supplying 25% of the electrically supplied homes).
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Hoetman, Agus Rusyana. "A computational and experimental study of a solar powered Rankine cycle engine for use in Jakarta." Thesis, University of Salford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292902.
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Yossef, Delav, and Dino Hot. "Comparative life cycle assessment of organic building materials." Thesis, Högskolan Dalarna, Institutionen för information och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:du-37774.
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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 %.
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Box, Jeffrey 1969. "Physiological responses of superb fairy-wrens to energy challenges during their annual cycle." Monash University, Dept. of Biological Sciences, 2002. http://arrow.monash.edu.au/hdl/1959.1/7626.
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Sahu, Siddharth. "Optimizing methods and materials for maximizing energy recovery and energy generation in the Capacitive Double Layer Expansion cycle." Thesis, KTH, Tillämpad fysik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-266819.
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Sathre, Roger. "Life-Cycle Energy and Carbon Implications of Wood-Based Products and Construction." Doctoral thesis, Mittuniversitetet, Institutionen för teknik, fysik och matematik, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-50.
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Forests can be an important element of an overall strategy to limit the atmospheric concentration of carbon dioxide (CO2) that contributes to climate change. As an integral part of the global carbon cycle, forests remove CO2 from the atmosphere as they grow, and accumulate carbon in tree biomass. Using wood products made from sustainably managed forests can reduce net CO2 emission by substituting in place of fossil fuels and energy-intensive materials. In this thesis the mechanisms by which wood product substitution can affect energy and carbon balances are studied. These include: the energy needed to manufacture wood products compared with alternative materials; the avoidance of industrial process carbon emission from e.g. cement manufacture; the use of wood by-products as biofuel to replace fossil fuels; and the physical storage of carbon in forests and wood materials. A methodological framework is first developed by integrating knowledge from the fields of forestry, industry, construction, and energy. A life cycle perspective is employed encompassing the entire product chain from natural resource acquisition to material disposal or reuse. Analytical challenges that are addressed include the functional unit of comparison, the fossil reference system, land use issues of wood vs. non-wood materials, and the diverse phases of the product life cycle. The methodology is then applied to two multi-storey wood-framed buildings in Sweden and Finland, compared with two functionally equivalent buildings with reinforced concrete structural frames. The results show that less primary energy is needed to produce the wood-framed buildings than the concrete-frame buildings. CO2 emission is significantly lower for the wood-frame buildings, due to reductions in both fossil fuel use and cement calcination process emission. The most important single factor affecting the energy and carbon balances is the use of biomass by-products from the wood product chain as biofuel to replace fossil fuels. Over the life cycle of the wood-framed buildings, the energy of biomass residues from forest operations, wood processing, construction and demolition is greater than the energy inputs to produce the materials in the buildings. Realisation of this benefit is facilitated by integrating and optimising the biomass and energy flows within the forestry, industrial, construction, energy, and waste management sectors. Different forest management regimes are studied in an integrated carbon analysis to quantify the carbon flows and stocks associated with tree biomass, soils, and forest products. Intensified forest management that produces greater quantities of biomass leads to net CO2 emission benefits by augmenting the potential to substitute for fossil fuels and non-wood materials. The increased energy use and carbon emission required for the more intensive forest management, as well as the slight reduction in soil carbon accumulation due to greater removal of forest residues, are more than compensated for by the emission reduction due to product substitution. Carbon stock changes in forests and wood materials can be temporarily significant, but over the building life cycle and forest rotation period the stock change becomes insignificant. In the long term, the active and sustainable management of forests, including their use as a source for wood products and biofuels, allows the greatest potential for reducing net CO2 emission. Implementation issues related to the wider use of wood-based materials to reduce energy use and carbon emission are also explored. An analysis of the effects of energy and taxation costs on the economic competitiveness of materials shows that the cost of energy for material processing, as a percentage of the total cost of finished material, is lower for wood products than for other common non-wood building materials. Energy and carbon taxation affects the cost of wood products less than other materials. The economic benefit of using biomass residues to substitute for fossil fuels also increases as tax rates increase. In general, higher taxation of fossil fuels and carbon emission increases the economic competitiveness of wood construction. An analysis of added value in forest product industries shows that greater economic value is added in the production of structural building materials than in other uses of forest biomass. Co-production of multiple wood-based products increases the total value that is added to the biomass produced on an area of forest land. The results show that production of wood-based building material is favoured economically by climate change mitigation policies, and creates high added value within forest product industries.Skogsresurser kan utgöra en viktig del i en strategi för att begränsa koncentrationen av koldioxid (CO2) i atmosfären och därmed begränsa klimatförändringarna. Skog tar upp CO2 från atmosfären när den växer och kolet lagras i trädens biomassa. Trädprodukter från hållbart brukade skogar kan minska nettoutsläppen av CO2 genom att de kan ersätta fossilt bränsle och energiintensiva material. I denna avhandling studeras faktorer som påverkar energi- och kolbalanser när träprodukter ersätter alternativa produkter. Signifikanta faktorer är den energi som behövs för att framställa träprodukter jämfört med alternativa produkter, utsläpp av CO2 från industriella processer som vid cementproduktion, ersättning av fossilt bränsle med trärester samt lagring av kol i skog och träprodukter. En metodik har utvecklats för att studera dessa faktorer genom att integrera ämneskunskaper från byggkonstruktion, energi, industri och det skogliga området. Den bygger på ett livscykelperspektiv och innefattar hela material- och produktkedjor från naturresurs till avfall eller återanvändning av material eller produkter. De metodikfrågor som varit i fokus är den funktionella enheten för jämförelser, det fossila referenssystemet, utnyttjande av skogmark vid produktion av träprodukter samt produktens olika faser under en livscykel. Metodiken har sedan använts för att jämföra ett svenskt och ett finskt flervåningshus i trä med två funktionellt likvärdiga hus med betongstomme. Resultaten visade att det behövs mindre primärenergi för att tillverka trähuset än betonghuset. Energin som kan utvinnas från biprodukter under en träbyggnads livscykel – från skogsskötsel, förädling, konstruktion och rivning – är större än den energi som krävs för att tillverka byggnadsmaterialet i byggnaden. Nettoutsläppen av CO2 från både fossil primärenergi och cementkalcinering är också väsentligt lägre för trähuset, men användningen av biprodukter från skogsavverkning, träförädlingskedjan och rivningsvirke för att ersätta fossilt bränsle har störst påverkan på kolbalansen. För att fullt ut tillgodogöra sig biprodukters potentiella fördelar krävs att de olika sektorerna för skogsbruk, industri, konstruktion, energi och avfallshantering integreras och optimeras med avseende på energi- och materialflöden. Olika skogsskötselmetoder har analyserats för att kvantifiera de flöden och den lagring av kol som sker i biomassa, mark och träprodukter. Intensifierat skogsbruk gav mindre utsläpp av CO2 per ha skogsmark, eftersom potentialen ökade för att ersätta fossila bränslen och energiintensiva material. Denna substitutionseffekt kompenserade mer än väl för den ökning i energianvändning och de utsläpp av CO2 som den intensivare skogsskötseln medförde, inklusive för den minskning av lagrat kol i marken som uttaget av skogsrester medförde. Lagring av kol i skogar och träprodukter kan vara intressant i ett kort tidsperspektiv, men under en byggnads livscykel och ett skogsbestånds rotationsperiod har den liten betydelse. I längden uppnås den största minskningen av CO2-utsläpp genom en aktiv och hållbar skogsskötsel med uttag av skogsresurser för användning till träprodukter och energi. I denna avhandling studerades också hur användningen av träprodukter påverkas av energi- och miljöskatter. En analys av energi- och skattekostnadernas effekt på konkurrenskraften för trämaterial visade att energikostnaden är lägre för trämaterial än för andra vanliga byggmaterial. Energi- och koldioxidskatter påverkar träprodukter i mindre utsträckning än produkter i andra material. De ekonomiska fördelarna av att använda biomassa som ersättning för fossila bränslen ökar också med höjda skatter. Konkurrensfördelarna för träkonstruktioner ökar därför generellt i takt med högre skatt på fossila bränslen och CO2-utsläpp. En analys av förädlingsvärdet hos skogsprodukter visade på en större värdeökning vid produktion av byggnadsmaterial än för andra biomassebaserade produkter. Samproduktion av flera träprodukter ökade det totala värdet hos biomassan per skogsareal. Resultaten visade att produktion av träbaserade byggnadsmaterial får ekonomiska fördelar av klimatpolitiska åtgärder och att sådan produktion har ett högt förädlingsvärde för industrierna i träbranschen.
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Primard, Pierre. "Life-cycle studies on raw materials for renewable energy development in France." Thesis, KTH, Kraft- och värmeteknologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-167354.
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The present report is a reflection on the impact and costs of raw materials involved in renewable energy (RE) technology development. The study is performed in collaboration with ADEME in France and is based on a range of previous studies initiated by ADEME, which aimed to test the limits for the integration of renewables in the energy mix by considering their raw material consumption and identifying the possible impacts if this consumption steadily grows in the future. The Earth’s material resources are already under heavy pressure, especially the exotic metals used in advanced technologies including renewable energy components and equipment. A sharp rise in material consumption due to a wide deployment of renewable energy could harm the metal markets and endanger the industries that depend on them. Securing a sustainable development path for RE technologies would require avoiding any fast resource depletion. This thesis focuses on several modern RE technologies, identifies their specific raw material consumption and points out some important strategic and economic issues regarding their sustainability. The possible penetration in the energy mix of France of different RE technologies related to their life-cycle and cost implications of the involved raw materials is discussed. The study also compares the requirement of raw materials for a 100%-RE energy system to a more conventional mix where the larger part is allocated to nuclear power and fossil fuels. By identifying the weaknesses and strengths of the renewable energy technologies as far as materials are concerned, the author aims at promoting the idea that a detailed Life Cycle Assessment of a project during the planning phase is a useful tool for the decision process and an important first step towards a more sustainable energy mix.
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Hashemi, Farzad Tabassom. "Life Cycle Assessment (LCA) for a DC-microgrid energy system in Fjärås." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-263173.
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Application of Photovoltaic PV panels for electricity production has rapidly increased in recent years in Sweden after launching a capital subsidy for PV panel installations in 2009. Kungsbacka municipality’s housing company equipped two groups of buildings in Fjärås with PV systems to generate electricity. The newly built residential buildings are connected to a DC-microgrid, whereas the existing buildings have been equipped with a single PV system. This project conducts a cradle to gate life cycle assessment (LCA) for this DC-microgrid energy system. The main purpose of this project is to determine which parts and processes of the DC-microgrid contribute to highest environmental impact throughout their lifespan from cradle to gate stages. Moreover, this study explores the energy payback time (EPBT) and the cumulative energy demand (CED) for the DC-microgrid. Additionally, this study performs two comparative LCA. First the DC-microgrid is being compared with PV system to determine which system has higher environment impacts, and secondly, the DC-microgrid is being compared with the average electricity mix in Sweden in terms of contribution to environmental impacts. The LCA follows the ISO 14040 framework and the baseline method is applied in order to assess 11 environmental impact categories. Two different functional units are adopted in this study. One is based on installed kilowatt peak (kWp) capacity by which environmental impacts of the PV system are compared with the DC-microgrid system. The other functional unit for this study is 1 kWh of delivered electricity to residential buildings produced by the DC-microgrid system. This functional unit is used exclusively for a stand-alone analysis of the DC-microgrid system in order to make it comparable with other microgrid systems or other systems with different energy sources, such as hydro, wind or nuclear. The results of the stand-alone LCA analysis of the DC-microgrid show that the battery has high contribution in human toxicity and terrestrial ecotoxicity whereas the energy hub system (Ehub) is the main contributor to eutrophication, abiotic depletion, fresh water aquatic ecotoxicity and marineaquatic ecotoxicity. The monocrystalline PV panel has the highest impact on global warming and abiotic depletion (fossil fuel). In addition, the EPBT for the DC-microgrid system is approximately 3.7 years. This means that one can get energy free of cost for an estimated time of 26.5 years if the lifetime of the system is assumed to be 30 years. The CED results show that monocrystalline PV production is an intense energy process which requires more non-renewable energy than all remaining parts of the DC-microgrid. The comparison of the DC-microgrid with the PV system reveals that the DC-microgrid has a higher environmental impact almost in all impact categories. This is mainly due to batteries and inverters which have a clear effect on the result. The CED analysis results illustrate that the multicrystalline PV panel production from the PV system is the most energy demanding process in both categories of renewable and non-renewable energy source. Moreover, the analysis illustrates that the DC-microgrid has still higher environmental impacts in all impact categories compared to the average electricity mix in Sweden. This is due to the electricity production in Sweden relies on hydropower and nuclear power with around 83 % of the total electricity production in the year 2017 which causes a lower environmental burden. Although the DC microgrid system shows a higher environmental impact compared to PV system, it is still a proper option to generate electricity since DC-microgrid system allows to achieve some indirect advantages such as energy saving due to an increase in own usage rate and self-sufficiency rate compared to the PV system. It should be noted that the end-of-life procedures becomes very important especially when crediting back for the recycling of materials. The collection and recycling of the PV panels at their end-of-life should be considered for future work as soon as reliable data are available.Användningen av solpaneler har de senaste åren kommit att öka markant i Sverige. Ökningen beror på det statliga bidraget för installation av solceller som lanserades 2009. Kungsbacka kommun installerade solcellssystem i två olika typer av byggnader, ny och äldre befintlig byggnad. Den nya byggnaden anslöts till direkt mikronät (DC-mikcrogrid) och den äldre byggnaden utrustades med solcellssystem. Detta projekt utför en ’från vaggan till porten’ livscykelanalys (LCA) för energisystemet direkt mikronät. Syftet är i huvudsak att fastställa vilka delar och processer av det direkta mikronätet som bidrar till störst miljöpåverkan genom dess livslängd, det vill säga från vaggan till porten. Vidare undersöker studien återbetalningstiden (Energy PayBack Time, EPBT) och den ackumulerade energianvändningen (Cumulative Energy Demand, CED) för det direkta mikronätet. Studien utför två komparativa LCA varpå det direkta mikronätet först jämförs med solcellssystemet i syfte att fastställa vilket av systemen har större miljöpåverkan. Studien ämnar också jämföra det direkta mikronätet med den genomsnittliga energimixen i Sverige, också avseende miljöpåverkan. LCA metoden följer ISO 14040-ramverket. Studien är baserad på två funktionella enheter vilka består av installerad kilowatt peak (kWp) kapacitet vilken används för att jämföra solcellssystemet och det direkta mikromåttet. Den andra funktionella enheten är 1 kWh levererad elektricitet till bostäder som producerats genom det direkta mikronätet. Denna funktionella enhet används för en ’stand-alone’ analys av det direkta mikronätet i syfte att göra det jämförbart med andra mikrosystem eller system med olika energikällor så som vatten-, vind- och kärnkraft. Resultaten från ‘stand-alone’ livscykelanalysen av det direkta mikronätet visar på att batteriet har en större effekt på mänsklig toxicitet terrestrisk ekotoxicitet, varpå systemet för energihubb bidrar främst till övergödning, abiotisk utarmning, vattenlevande ekotoxicitet och havslevande ekotoxicitet. Monokristallin solpanel har större påverkan på global uppvärmning och övergödning (fossilabränslen). I övrigt är EPBT för det direkta mikronätet cirka 3,7 år vilket innebär att energin beräknas kostnadsfri i cirka 26,5 år, givet att det kan antas att systemets livslängd är 30 år. CED-resultat visar på att microkristallin solpanel är en intensiv energiprocess som kräver mer icke-förnybar energi jämfört med resterande delar av det direkta mikronätet. Jämförelsen mellan det direkta mikronätet och solcellssystemet visar på att det direkta mikronätet har större miljöpåverkan i de flesta kategorier. Detta beror i huvudsak på batterier och växelriktare som har tydlig effekt på resultatet. Av resultatet från CED-analysen framgår att produktion av multikristallin solpanel av solcellssystemet är det mest energikrävande processen i båda kategorierna för förnybar och icke-förnybar energikälla. Vidare framgår av analysen att det direkta mikronätet har en större miljöpåverkan i alla kategorier, jämfört med påverkan från genomsnittet av energimixen i Sverige. Detta beror på att elproduktionen i Sverige mestadels består av vatten- och kärnkraft som tillsammans 2017 utgjorde 83 procent av den totala energiproduktionen. Denna produktion orsakaren mindre miljöbelastning. Trots att det direkta mikronätet påvisar en högre miljöpåverkan än solcellssystemet, är det fortfarande ett alternativ till att generera elektricitet eftersom det direkta mikronätet bidrar till indirekta fördelar såsom energibesparing. Energibesparingen i det direkta mikronnätet sker således genom ökad användning av den egenproducerade energin samt självförsörjning. Det ska vidare tilläggas att ’end-of-life’ procedurerna blir viktiga i synnerhet när de återvunna materialet återanvänds. Vidare bör solpaneler återanvändas vid ’end-of-life’ vilket bör finnas i åtanke för vidarestudier och i samband med att data tillgängliggörs.
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El-khawas, Ihab N. "The optimal design of buildings : a life-cycle approach to energy efficiency /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487948158626783.
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Almsalati, Hussam. "Life cycle assessment of villas made by Fiskarhedenvillan, comparison between wood and brick facade." Thesis, Högskolan Dalarna, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:du-28672.
Full textAbstract:
Awareness of climate change has resulted in enormous challenges for developed and developing countries. The frightening truth about our environmental situation has led to investigations of the causes of these changes and to obstruct these sources gradually but quickly. The alarming increase of average temperature of the earth has caused much worry around the world. Gas emissions in the atmosphere greatly affect the environment, where CO 2 emissions is one of the most serious factors contributing to the global warming potential. As the building sector emits 40% of global energy use and one-third of global greenhouse gas emissions, engineers must be educated to choose the best materials that lead to reducing CO 2 emissions. This means selecting materials that have less negative impact on the environment and are more “environmentally friendly”. This study shows how much CO 2e emissions are released into the atmosphere from a wooden structure villa that consists of two stories, a storage and a garage, with a total area of 229.6m2. The results of this case will be compared to a second case, where the external wooden siding is replaced with brick veneer. This result of this comparison provides us with a guideline in for how the selected materials impact the environment, illuminating the importance in choosing the right materials according to their CO 2e emission levels. In this way, the building sector can actively work to reduce the environmental impact. To achieve these goals, this study performed via life cycle assessment LCA methodology by using the One-Click LCA program. LCA is identified as a technique to assess the environmental impact and resources used through a product’s life cycle. This study utilized the LCA methodology (cradle to grave), which means starting from the extraction of raw materials, to product production, manufacturing, product usage and its end of life. The study lifespan was estimated to be 50 years. The results of the study verify that the wooden villa is more environmentally friendly than the villa made of brick, where carbon dioxide equivalent emission can be reduced to more than half by utilizing wood. Implementing the life cycle assessment study to any building aids in making the decision to choose the right materials for building according to CO 2e emission. And in this way, the environmental impact caused by the building sector will be greatly reduced.
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Dahlsten, Hilda. "Life Cycle Assessment of Electricity from Wave Power." Thesis, Institutionen för energi och teknik, SLU, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-162582.
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The use of ocean wave energy for electricity production has considerable potential, though it has proven to be difficult. A technology utilizing the heaving (up-and-down) motions of the waves was conceived at Uppsala University in the early 2000´s, and is being further developed for commercial use by Seabased Industry AB. The purpose of this master´s degree project was to increase the knowledge of the environmental performance of Seabased´s wave energy conversion concept and identifying possible areas of improvement. This was done by conducting a life cycle assessment (LCA) of a hypothetical prototype wave power plant. All flows of materials, energy, emissions and waste were calculated for all stages of a wave power plant´s life cycle. The potential environmental impact of these flows was then assessed, using the following impact categories: • Emission of greenhouse gases • Emission of ozone depleting gases • Emission of acidifying gases • Emission of gases that contribute to the forming of ground-level ozone • Emission of substances to water contributing to oxygen depletion (eutrophication) • Energy use (renewable and non-renewable) • Water use The methodology used was that prescribed by the ISO standard for Environmental Product Declarations (EPD) and further defined by the International EPD Programme.The potential environmental impact was calculated per kWh of wave power electricity delivered to the grid. The main result of the study is that the potential environmental impact of a wave power plant mainly stems from the manufacturing phase. In particular, the production of steel parts makes a large contribution to the overall results. Future wave power plant designs are expected to be considerably more material efficient, meaning that there are large possibilities to improve the environmental performance of this technology.
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Connelly, Michael. "An Analysis of Innovation in Materials and Energy." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1273521462.
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Nyoni, Bothwell. "Simulation of the sulphur iodine thermochemical cycle / Bothwell Nyoni." Thesis, North-West University, 2011. http://hdl.handle.net/10394/6685.
Full textAbstract:
The demand for energy is increasing throughout the world, and fossil fuel resources are diminishing. At the same time, the use of fossil fuels is slowly being reduced because it pollutes
the environment. Research into alternative energy sources becomes necessary and important. An alternative fuel should not only replace fossil fuels but also address the environmental challenges
posed by the use of fossil fuels. Hydrogen is an environmentally friendly substance considering that its product of combustion is water. Hydrogen is perceived to be a major contender to replace
fossil fuels. Although hydrogen is not an energy source, it is an energy storage medium and a carrier which can be converted into electrical energy by an electrochemical process such as in fuel cell technology.
Current hydrogen production methods, such as steam reforming, derive hydrogen from fossil
fuels. As such, these methods still have a negative impact on the environment. Hydrogen can also be produced using thermochemical cycles which avoid the use of fossil fuels. The production of hydrogen through thermochemical cycles is expected to compete with the existing hydrogen production technologies. The sulphur iodine (SI) thermochemical cycle has been identified as a high-efficiency approach to produce hydrogen using either nuclear or solar power.
A sound foundation is required to enable future construction and operation of thermochemical cycles. The foundation should consist of laboratory to pilot scale evaluation of the process. The
activities involved are experimental verification of reactions, process modelling, conceptual design and pilot plant runs. Based on experimental and pilot plant data presented from previous research, this study presents the simulation of the sulphur iodine thermochemical cycle as applied to the South African context. A conceptual design is presented for the sulphur iodine
thermochemical cycle with the aid of a process simulator.
The low heating value (LHV) energy efficiency is 18% and an energy efficiency of 24% was achieved. The estimated hydrogen production cost was evaluated at $18/kg.Thesis (M.Ing. (Chemical Engineering))--North-West University, Potchefstroom Campus, 2012.
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Butt, Ali Azhar. "Life Cycle Assessment of Asphalt Pavements including the Feedstock Energy and Asphalt Additives." Licentiate thesis, KTH, Väg- och banteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-102763.
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Roads are assets to the society and an integral component in the development of a nation’s infrastructure. To build and maintain roads; considerable amounts of materials are required which consume quite an amount of electrical and thermal energy for production, processing and laying. The resources (materials and the sources of energy) should be utilized efficiently to avoid wastes and higher costs in terms of the currency and the environment. In order to enable quantification of the potential environmental impacts due to the construction, maintenance and disposal of roads, an open life cycle assessment (LCA) framework for asphalt pavements was developed. Emphasis was given on the calculation and allocation of energy used for the binder and the additives. Asphalt mixtures properties can be enhanced against rutting and cracking by modifying the binder with additives. Even though the immediate benefits of using additives such as polymers and waxes to modify the binder properties are rather well documented, the effects of such modification over the lifetime of a road are seldom considered. A method for calculating energy allocation in additives was suggested. The different choices regarding both the framework design and the case specific system boundaries were done in cooperation with the asphalt industry and the construction companies in order to increase the relevance and the quality of the assessment. Case-studies were performed to demonstrate the use of the LCA framework. The suggested LCA framework was demonstrated in a limited case study (A) of a typical Swedish asphalt pavement. Sensitivity analyses were also done to show the effect and the importance of the transport distances and the use of efficiently produced electricity mix. It was concluded that the asphalt production and materials transportation were the two most energy consuming processes that also emit the most GreenHouse Gases (GHG’s). The GHG’s, however, are largely depending on the fuel type and the electricity mix. It was also concluded that when progressing from LCA to its corresponding life cycle cost (LCC) the feedstock energy of the binder becomes highly relevant as the cost of the binder will be reflected in its alternative value as fuel. LCA studies can help to develop the long term perspective, linking performance to minimizing the overall energy consumption, use of resources and emissions. To demonstrate this, the newly developed open LCA framework was used for an unmodified and polymer modified asphalt pavement (Case study B). It was shown how polymer modification for improved performance affects the energy consumption and emissions during the life cycle of a road. From the case study (C) it was concluded that using bitumen with self-healing capacity can lead to a significant reduction in the GHG emissions and the energy usage. Furthermore, it was concluded that better understanding of the binder would lead to better optimized pavement design and thereby to reduced energy consumption and emissions. Production energy limits for the wax and polymer were determined which can assist the additives manufacturers to modify their production procedures and help road authorities in setting ‘green’ limits to get a real benefit from the additives over the lifetime of a road.QC 20120926
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McNeil, Jessica N. "The Effects of Menstrual Cycle Phases and Adiposity on Energy Balance in Women." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20336.
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Energy intake (EI) and energy expenditure (EE) across the menstrual cycle (MC), while considering body adiposity, have not been previously evaluated in the same individuals. This study mainly examined the variations in energy balance (EB) across MC. Seventeen women (Body fat-DXA:28.5%) participated in three identical sessions during distinct phases of the MC: Early-follicular, Late-follicular/ovulation and Mid-luteal (confirmed by basal temperature and sex-steroid hormones). EI, resting metabolic rate (RMR), physical-activity EE (PAEE), severity of PMS, leptin and relative-reinforcing value (RRV) of preferred foods were measured during each phase. No differences in body fat, EI, RMR, PAEE, leptin and RRV of food were noted across MC. Trends were noted in preferred snack (p=0.06) and combined snack/fruit (p=0.06) intakes, while differences were noted in severity of PMS (p<0.05) across phases. Changes in EB across the MC were not noted. PMS was more severe, and preferred snack and combined snack/fruit intakes were slightly higher during mid-luteal phase.
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Fisher, Neil R. "The cycle of turbulent energy dissipation and mixing in regions of freshwater influence." Thesis, Bangor University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401906.
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Vaupel, Andreas. "High Energy, High Average Power, Picosecond Laser Systems to Drive Few-Cycle OPCPA." Doctoral diss., University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5881.
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The invention of chirped-pulse amplification (CPA) in 1985 led to a tremendous increase in obtainable laser pulse peak intensities. Since then, several table-top, Ti:sapphire-based CPA systems exceeding the 100 TW-level with more than 10 W average power have been developed and several systems are now commercially available. Over the last decade, the complementary technology of optical parametric chirped-pulse amplification (OPCPA) has improved in its performance to a competitive level. OPCPA allows direct amplification of an almost-octave spanning bandwidth supporting few-cycle pulse durations at center wavelengths ranging from the visible to the mid-IR. The current record in peak power from a table-top OPCPA is 16 TW and the current record average power is 22 W. High energy, few-cycle pulses with stabilized carrier-envelope phase (CEP) are desired for applications such as high-harmonic generation (HHG) enabling attoscience and the generation keV-photon bursts. This dissertation conceptually, numerically and experimentally describes essential aspects of few-cycle OPCPA, and the associated pump beam generation. The main part of the conducted research was directed towards the few-cycle OPCPA facility developed in the Laser Plasma Laboratory at CREOL (University of Central Florida, USA) termed HERACLES. This facility was designed to generate few-cycle pulses in the visible with mJ-level pulse energy, W-level average power and more than 100 GW peak power. Major parts of the implementation of the HERACLES facility are presented. The pump generation beam of the HERACLES system has been improved in terms of pulse energy, average power and stability over the last years. It is based on diode-pumped, solid-state amplifiers with picosecond duration and experimental investigations are presented in detail. A robust system has been implemented producing mJ-level pulse energies with ~100 ps pulse duration at kHz repetition rates. Scaling of this system to high power (>30 W) and high peak power (50-MW-level) as well as ultra-high pulse energy (>160 mJ) is presented. The latter investigation resulted in the design of an ultra-high energy system for OPCPA pumping. Following this, a new OPCPA facility was designed termed PhaSTHEUS, which is anticipated to reach ultra-high intensities. Another research effort was conducted at CELIA (Univerist&"233; de Bordeaux 1, France) and aimed towards a previously unexplored operational regime of OPCPA with ultra-high repetition rates (10 MHz) and high average power. A supercontinuum seed beam generation has been established with an output ranging from 1.3 to 1.9 ?m and few ps duration. The pump beam generation has been implemented based on rod-type fiber amplifiers producing more than 37 W average power and 370 kW peak power. The utility of this system as an OPCPA pump laser is presented along with the OPA design. The discussed systems operate in radically different regimes in terms of peak power, average power, and repetition rate. The anticipated OPCPA systems with few-cycle duration enable a wide range of novel experimental studies in attoscience, ultrafast materials processing, filamentation, LIBS and coherent control.Ph.D.
Doctorate
Optics and Photonics
Optics and Photonics
Optics
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Shin, Hyun. "Life-Cycle Cost-Based Optimal Seismic Design of Structures with Energy Dissipation Devices." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/40399.
Full textAbstract:
Seismic designs of building structures are currently made based on the design criterion
of life-safety and this requires that the structures do not collapse to compromise safety
of people in the structure, but they can be designed to experience some damage.
However, this design approach has allowed large economic losses primarily due to the
damage to the nonstructural components at relatively moderate levels of seismic
intensities. This led to a new thinking about design approach called performance-based
design approach that satisfies the life-safety objective at the same time, reduces the
economic loss to an acceptable level. The performance-based design approaches are
multi-level design that addresses several different levels of structural performances
under different levels of seismic intensities. In this study, we have investigated the use
of energy dissipating damping devices to achieve the performance of a building
structure in a desirable manner over all levels of seismic intensity. Since the initial
motivation of performance-based design was reducing economic loss, the life-cycle
cost-based optimization is considered in this study to obtain the optimal designs with
different damping devices. For the optimal design, three types of devices are used in this
study: fluid viscous dampers, solid visco-elastic dampers, and yielding metallic
dampers. The combinations of two different types of dampers are also examined in this
study. The genetic algorithm (GA) approach is adopted as an optimizer that searches for
the optimal solution in an iterative manner. Numerical results from the application of
the optimal design to the selected model building are presented to demonstrate the
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applicability of the developed approach and to estimate the effectiveness of the obtained
optimal design with each device. It is shown in the results that the optimal design with
each individual damping devices or the combination of two different types of damping
devices are very effective in reducing the expected failure cost as well as the
displacement response quantities and fragilities. The results also show that the optimal
designs focus relatively more on reducing economic losses for the lower but more
frequent excitation intensities as these intensities contribute most to the failure costs.Ph. D.
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Nie, Zhenggang. "Life Cycle Modelling of Carbon Dioxide Capture and Geological Storage in Energy Production." Thesis, Imperial College London, 2009. http://hdl.handle.net/10044/1/9016.
Full textAbstract:
Carbon dioxide (CO2) capture and geological storage (CCS) is recognised as one of themain options in the portfolio of greenhouse gas (GHG) mitigation technologies beingdeveloped worldwide. The CO2 capture and storage technologies require significantamounts of energy during their implementation and also change the environmentalprofile of power generation. The holistic perspective offered by Life Cycle Assessment(LCA) enables decision makers to quantify the trade-offs inherent in any change to thepower production systems and helps to ensure that a reduction in GHG emissions doesnot result in significant increases in other environmental impacts. Early LCA studies ofpower generation with CCS report a wide range of results, as they focus on specific CO2capture cases only. Furthermore, previous work and commercial LCA software have arigid approach to system boundaries and do not recognise the importance of the level ofdetail that should be included in the Life Cycle Inventory (LCI) data. This research developed a complete LCA framework for the ?cradle-to-grave?assessment of alternative CCS technologies in carbon-containing fuel power generation. A comprehensive and quantitative Life Cycle Inventory (LCI) database, which modelsinputs/outputs of processes at high level of detail, accounts for technical and geographicdifferences, generates LCI data in a consistent and transparent manner was developedand arranged and flexible structure. The developed LCI models were successfully applied to power plants with alternativepost-combustion chemical absorption capture and oxy-fuel combustion capture. Theresults demonstrate that most environmental impacts come from power generation withCCS and the upstream process of coal production at a life-cycle perspective. LCAresults are sensitive to the type of coal used and the CO2 capture options chosen. Moreover, the models developed successfully trace the fate of elements (including tracemetals) of concern throughout the power generation, CO2 capture, transport andinjection chain. Monte Carlo simulation method combined with the LCI models wasapplied to quantify the uncertainty of emissions of concern. A novel analytical framework for the LCA of CO2 storage was also developed andapplied to a saline aquifer storage field case. The potential CO2 leakage rates werequantified and the operational and geological parameters that determine the ratio of CO2leakage total volume of CO2 injected were identified.