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Determining anchoring systems for marine renewable energy devices moored in a western boundary currentUnknown Date (has links)
In this thesis anchoring systems for marine renewable energy devices are examined for an area of interest off the coast of Southeast Florida that contains both ocean current and thermal resources for future energy extraction. Bottom types observed during previous regional benthic surveys are compiled and anchor performance of each potential anchor type for the observed bottom types is compared. A baseline range of environmental conditions is created by combining local current measurements and offshore industry standards. Numerical simulations of single point moored marine hydrokinetic devices are created and used to extract anchor loading for two potential deployment locations, multiple mooring scopes, and turbine rotor diameters up to 50 m. This anchor loading data is used for preliminary anchor sizing of deadweight and driven plate anchors on both cohesionless and cohesive soils. Finally, the capabilities of drag embedment and pile anchors relevant to marine renewable energy devices are discussed. / by Michael Grant Seibert. / Thesis (M.S.C.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
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Design of a power management model for a solar/fuel cell hybrid energy systemUnknown Date (has links)
This thesis proposes a Power Management Model (PMM) for optimization of several green power generation systems. A Photovoltaic/Fuel cell Hybrid Energy System (PFHES) consisting of solar cells, electrolyzer and fuel cell stack is utilized to meet a specific DC load bank for various applications. The Photovoltaic system is the primary power source to take advantage of renewable energy. The electrolyzer-fuel cell integration is used as a backup and as a hydrogen storage system with the different energy sources integrated through a DC link bus. An overall power management strategy is designed for the optimization of the power flows among the different energy sources. Extensive simulation experiments have been carried out to verify the system performance under PMM governing strategy. The simulation results indeed demonstrate the effectiveness of the proposed approach. / by Rosana Melendez. / Thesis (M.S.C.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.
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Design of hydrodynamic test facility and scaling procedure for ocean current renewable energy devicesUnknown Date (has links)
Simulations have been carried out to validate a hydrokinetic energy system non-dimensional scaling procedure. The requirements for a testing facility intended to test such devices will be determined from the results of the simulations. There are 6 simulations containing 3 prototype systems and 2 possible model facility depths to give a range of results. The first 4 tests are conducted using a varying current profile, while the last 2 tests use a constant current profile of 1.6 m/s. The 3 prototype systems include a: 6 m spherical buoy, a 12 m spherical buoy and a turbine component system. The mooring line used for the simulations is a 6x19 Wire Rope Wire Core of diameter 100 mm and length 1000 m. The simulations are implemented using Orcaflex to obtain the dynamic behavior of the prototype and scaled system. / by William Valentine. / Thesis (M.S.C.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
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Análise da intensidade energética: um estudo de caso para o Estado de São Paulo / Energy Intensity Analysis: A Case Study for the Sao Paulo StateOshiro, André Hideki Furukawa 20 March 2015 (has links)
O sistema energético pode ser visto não apenas como uma restrição, mas também como uma oportunidade para o desenvolvimento produtivo de uma sociedade. Pela segunda ótica, o objetivo principal a ser perseguido é a da garantia do suprimento energético e da adequação das formas e fontes de energia aos usos finais demandados. Ao mesmo tempo, dentro do contexto global de preocupação com as mudanças climáticas, faz-se necessário conceber uma nova trajetória de desenvolvimento para o estado de São Paulo, mais moderna, com maior participação de fontes renováveis de energia, focada na diminuição da ntensidade energética, e mais voltada ao desenvolvimento tecnológico. Este trabalho procurou, então, mostrar que o estado de São Paulo já promoveu uma verdadeira transformação de sua matriz energética em termos da participação de energias renováveis, no entanto, que os paulistas ainda devem encarar outros desafios maiores como saber lidar com a tendência não declinante de sua intensidade energética nos últimos anos. Enfim, ao decompor o indicador de intensidade energética para o estado de São Paulo, buscou-se explicitar as possíveis causas de forma a observar se há um tradeoff aparente entre o uso de fontes energéticas renováveis e a estagnação dos valores da intensidade energética estadual. / The energy system can be understood not only as a constraint, but also as an opportunity for a society productive development. Taking the second approach, the main objective to be pursued is that of securing energy supply and adequacy of forms and sources of energy to the demanded end uses. At the same time, within the context of global concern about climate change, it is necessary to devise a new development path for the state of São Paulo, more modern, with a higher share of renewable energy sources, focused on reduction of energy intensity and more focused on technological development. This study sought to show, therefore, that the state of São Paulo has promoted a true transformation of its energy matrix in terms of the share of renewable energies. However, the state must still face other major challenges such as how to deal with its non-downward energy intensity trend in recent years. Finally, by decomposing the energy intensity indicator for the state of São Paulo, we sought to clarify the possible causes in order to observe whether there is an apparent tradeoff between the use of renewable energy sources and the stagnation of the state energy intensity values.
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Matching renewal energy sources to rural development needs : a prototype design for a rural community development center for Jamaica, W.I.Jackson, Michael Onaje January 1982 (has links)
Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH. / Includes bibliographical references (leaf 112). / The opportunities for utilizing Jamaica/s rich supply of renewable energy resources as a base for stead, environmentally sound rural development is tremendous. This thesis explores as way of tapping this potential. Jamaica's current plans for both energy and rural community development are reviewed and general suggestions offered as to how the necessary integration of the two plans can be achieved for short and long term energy conscious planning and program implementation. The focus of the proposal is on the development of Rural Community Development Centers that would be designed to build a renewable energy infrastructural base for the specific communities and generally respond to the energy, educational and productive needs as they change over time. / by Michael Onaje Jackson. / M.Arch.
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Parametric and Mechanistic Studies of Biomass Conversion to High-Purity Hydrogen with Integrated Carbon FixationFerguson, Thomas Edward January 2014 (has links)
Due to the increasingly detrimental impacts of the global fossil fuel-driven energy economy, technological solutions that can mitigate the deleterious emissions from fossil fuel conversion or that can lessen societal dependence on fossil fuels are urgently required. The conversion of biomass, a renewable energy feedstock, into energy and fuels that are fungible with those derived from fossil fuels would help supplant some of the global fossil fuel consumption with sustainable energy generation. However, one of the main disadvantages of biomass as an energy feedstock when compared to fossil fuels is its low energy density. The majority of thermochemical biomass conversion technologies therefore focus on converting a low energy density feedstock in biomass to a higher energy density end product. Due to the operating parameters involved in these processes, they are typically accomplished on larger and more centralized scales by skilled operators. Few technologies exist that utilize biomass in a sustainable manner under a distributed energy framework, which would allow energy consumers to use locally available resources and waste material to generate energy.
The alkaline thermal treatment of biomass has recently been proposed as a novel method for producing high purity H₂ with suppressed COₓ formation under moderate reaction conditions (i.e., 573 K and ambient pressure). Essentially, biomass, which in this study were the model compounds of glucose and cellulose, is reacted with an alkali metal hydroxide, such as NaOH, in such a molar proportion that all of the carbon and oxygen embodied in the reactants is fixed as an alkali metal carbonate, while all of the elemental hydrogen is released as pure H₂ gas. Thus, fuel cell ready H₂ can be produced from biomass in a single reactor. This technology has great potential for sustainable bioenergy production since it can handle a wide range of feedstocks including biomass and biogenic wastes with high water content. In addition to having the potential to be a distributed energy generation technology, the alkaline thermal treatment of biomass could help meet increasing industrial demand for H₂ in a more sustainable manner, as 96% of current H₂ generation is derived from fossil fuels.
The alkaline thermal treatment technology is also relatively unexplored; thus, the effects of parameters such as feedstock type, reaction temperature, heating rate, NaOH:Biomass ratio, method of reactant mixing, flow of steam, and concentration of steam flow, on the gaseous and solid products formed are not fully understood. This study was undertaken to quantify the effects of these non-catalytic variables on the alkaline thermal treatment reaction and to elucidate potential reaction pathways in order to better evaluate the potential of the alkaline thermal treatment technology as a viable biomass conversion technology.
In the study of the alkaline thermal treatment of glucose, NaOH did play an important role in suppressing COₓ formation while facilitating H₂ production and promoting CH₄ formation. The non-catalytic alkaline thermal treatment of glucose in the absence of steam flow resulted in a maximum H₂ conversion of about 27% at 523 K with a stoichiometric mixture of NaOH and glucose. The solids analysis confirmed the presence of Na₂CO₃ in the solid product, indicating the inherent carbon management potential of the alkaline thermal treatment process. The addition of steam flow increased conversion to H₂ from 25% to 33%, while decreasing total CH₄ formation 5 fold.
After the investigation of the alkaline thermal treatment applied to glucose, cellulose was studied as a feedstock because it is the predominant component of lignocellulosic biomass, the target feedstock source for second generation biofuels. Like in the glucose study, it was found that H₂ and hydrocarbon formation occurred with the addition of NaOH to cellulose under thermal treatment, while the further addition of steam enhanced H₂ production and suppressed hydrocarbon formation. Both the enhancement of H₂ conversion and the suppression of hydrocarbon formation with the addition of steam flow was found to be more significant for cellulose than it was for glucose, with in the cellulose case H₂ conversion doubling from 25% to 48%, and CH₄ formation falling 35 times from the no steam flow case. Also like the glucose study, much of the carbon and oxygen present in the reactants were converted to Na₂CO₃.
With the knowledge gained about the effects various reaction parameters had on the alkaline thermal treatment reaction, a study of the reaction pathways of the alkaline thermal treatment of cellulose reaction was undertaken. Compounds formed at intermediate temperatures were identified, tested for gaseous production when reacted with NaOH, and the gas product formation rate trends of these reactions were compared with those trends observed from the alkaline thermal treatment of cellulose reaction. The intermediates identified included sodium carboxylate salts, namely sodium formate, sodium glycolate, and sodium acetate, among others. The reactions of these compounds with NaOH were found to yield H₂ and CH₄, with the gaseous formation rate trends being similar to trends observed for the alkaline thermal treatment reaction for cellulose in certain temperature regions. Particular focus was placed on sodium glycolate, which was an intermediate found in high concentration and that reacted with NaOH to produce both H₂ and CH₄. The formation of Na₂CO₃ at intermediate temperatures was also studied, and the comparison of Na₂CO₃ conversion to H₂ conversion at intermediate temperatures revealed that H₂ and Na₂CO₃ formation do not always occur at the 2:1 H₂:Na₂CO₃ molar ratio implied by the proposed stoichiometry of the alkaline thermal treatment reaction for cellulose. The aforementioned studies were conducted both in the presence and absence of steam flow to study its influence on the reaction.
Finally H₂ formation kinetic studies were performed on the alkaline thermal treatment of cellulose system as well as the H₂-producing sodium carboxylate salt reaction systems. Sodium formate and sodium oxalate were found to have better selectivity toward H₂ formation and their reactions were more kinetically favored than sodium glycolate with NaOH. A comparison of the isothermal H₂ kinetics between the cellulose and sodium glycolate systems at higher temperatures, however, revealed that H₂ conversion in the alkaline thermal treatment of cellulose appeared to be limited by the rate of conversion of sodium glycolate. From the results of these studies, recommendations are made for future research directions aimed at improving the alkaline thermal treatment of cellulose reaction.
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Electricity Market Reforms and Renewable Energy: The Case of Wind and Solar in BrazilBradshaw, Amanda January 2018 (has links)
This dissertation investigates the relationship between electricity market reforms and the development of renewable energy through interviews with policymakers, energy experts, and industry representatives in Brazil. Within the context of market-oriented power reforms initiated in the 1990s, policymakers have attempted to diversify the energy supply and reduce the country’s reliance on hydroelectric power. However, Brazil’s pre-existing hydropower infrastructure has hindered the diffusion of alternative options. By looking at energy auctions and net-metering regulations for wind and solar energy, this research explores the role of independent regulators in facilitating the development of non-hydro renewable sources of energy. While academic and policy debates center on designing public support schemes for renewable energy, this research argues that adaptive regulation can provide opportunities for new technologies that policy instruments alone are unable to achieve. In particular, the governance characteristics of regulatory agencies are critical to the effective articulation of renewable energy policies. Three subnational case studies further demonstrate how states and regions contribute to developing and deploying wind and solar energy technologies.
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Residential demand-side response in the UK : maximising consumer uptake and responseGross, Matthew John January 2018 (has links)
Residential demand-side response (DSR) is a key strategy for meeting the challenges facing the UK electricity system. Leveraging residential flexibility should help to enhance system reliability, reduce carbon emissions, support the integration of renewables into the energy mix and deliver a lower-cost electricity system. However, the viability of residential DSR hinges on two critical factors: consumers will first need to switch to DSR programmes in sufficient numbers and then successfully respond by adjusting their consumption patterns accordingly. This thesis explores how to optimise the impact of residential DSR by examining the enablers and constraints of uptake and response. While participation is primarily encouraged through financial incentives, studies suggest that some consumers may be willing to participate for nonfinancial reasons. As such, this thesis also explores how environmental and pro-social motivations could be leveraged to help promote uptake and response. The thesis contributes to the knowledge on DSR by testing UK consumer preferences for different programme models through a large-scale online survey and identifying measures which could help to maximise uptake. It also explores the potential afforded by dynamic information-only programmes through a trial based on available wind generation. The thesis further makes a theoretical contribution by exploring how the Fogg Behaviour Model (FBM) can be used to conceptualise the enablers and constraints of uptake and response. By mapping these factors to the FBM's core components of ability, motivation and trigger, the model is refined as a tool for understanding how to optimise the impact of residential DSR. The research reveals that information-only DSR programmes may represent a significant untapped resource. Approximately 8% of a representative sample of UK consumers indicated a preference for this model over more conventional price-based programmes; while trial households succeeded in reducing electricity consumption by 9.9% on average when asked to consume less and increasing consumption by 4.4% on average when asked to consume more. These promising findings may help to inform policy and programme design as the UK energy system evolves towards a renewables-based future.
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A fuzzy logic material selection methodology for renewable ocean energy applicationsUnknown Date (has links)
The purpose of this thesis is to develop a renewable ocean energy material selection methodology for use in FAU's Ocean Energy Projects. A detailed and comprehensive literature review has been performed concerning all relevant material publications and forms the basis of the developed method. A database of candidate alloys has been organized and is used to perform case study material selections to validate the developed fuzzy logic approach. The ultimate goal of this thesis is to aid in the selection of materials that will ensure the successful performance of renewable ocean energy projects so that clean and renewable energy becomes a reality for all. / by Donald Anthony Welling. / Thesis (M.S.C.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
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Sustainable energy transitions in Austria : a participatory multi-criteria appraisal of scenariosKowalski, Katharina January 2012 (has links)
In the light of advancing climate change and the anticipated scarcity of affordable fossil fuels, a transition towards more sustainable energy systems is vital to allow for the long-term sustainability of human wellbeing. Energy is a key sustainability issue, at the heart of the complex interactions of socioeconomic and biophysical systems. The overall aim of this study is to contribute to furthering the understanding of these systems interactions. It intends to deliver methodological insights on how to identify and appraise favourable energy futures in a changing and uncertain world. In order to cope with the complexity and uncertainty of future developments and with the plethora of partly contradictory social preferences, a participatory approach was combined with scenario development and the application of an appraisal tool that takes account of the multidimensionality of system interlinkages. In a case study for Austria, favourable renewable energy scenarios were developed in a participatory setting, involving key Austrian energy stakeholders. The scenario development consisted of two stages: first an exploratory stage with stakeholder engagement and second a modelling stage generating forecasting-type scenarios. Accordingly, the scenarios consist of a narrative part, the storyline, and a modelled, quantitative part. The application of Multi-Criteria Analysis (MCA) allowed the integration of multi-dimensional sustainability information (social, environmental, economic, and technological criteria) and the social preferences of the stakeholders into the appraisal of the energy scenarios. In the case study presented, five renewable energy scenarios for Austria for 2020 were compared against 17 sustainability criteria. The study illustrates how the combined use of participatory scenario building techniques and MCA acknowledges and integrates inherent complexity, irreducible uncertainty, multi-dimensionality, and, a multiplicity of legitimate perspectives in the appraisal. The main empirical result of the sustainability appraisal undertaken shows that, contrary to the current energy policy in Austria, a profoundly decentralised energy system (scenario E) and an innovative long-term investment strategy (scenario C) rank highest, whereas the renewable strategy based on biomass (scenario D), which represents the dominant political trajectory in Austria's renewable energy policy, ranks very low. The research demonstrates the integration of biophysical, social, economic, and, technological appraisal criteria, presents and discusses best practice criteria, and, illustrates the challenges and opportunities to incorporate bio-physical aspects into the concept of sociotechnical systems and their transitions in the light of a more sustainable development.
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