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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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OPTIMAL ENERGY DESIGN FOR A SYSTEM OF PUMPED HYDRO-WIND POWER PLANTSYANAMANDRA, LAKSHMI NAGA SWETHA January 2018 (has links)
SAMMANFATTNING Medvetenhet och oro kring miljöeffekter från utsläpp av växthusgaser och de minskande resurserna av icke förnybara energikällor har ökat de senaste årtiondena. Utvecklingen av ny teknologi för förnybar energi har drivits fram globalt som ett svar på denna oro. Det har skett stora framsteg i produktion av el och värme från sol, vind, hav, vattenkraft, biomassa, geotermiska resurser, biobränslen och väte. Följaktligen har utvecklingen av energi-lager blivit en viktig del för integration av förnybar energi i systemen. Det är gynnsamt för hela försörjningskedjan, för pålitlighet och bättre stabilitet i leveranser och distribution, och för ökad el-kvalitet. I uppsatsen undersöks en optimal energidesign för ett kombinerat system med vattenkraft och vindkraft inklusive ett lager i form av en damm. Vatten som pumpas upp till lagret har en stor och balanserande potential för att få in en högre grad förnybar energi i energisystemen. Detta är nödvändigt då dessa energikällor är intermittenta och variabla till sin natur. Ett av de studerade objekten är ett vattenkraftverk med pumpad damm, Tehri i Uttarakhand, Indien. Systemets totala verkningsgrad om 93 % diskuteras utifrån förluster såväl som potentialen för vind och dess inverkan. Vind-data är hämta från National Institute of Wind Energy (NIWE) och har analyserats med programmen MATLAB och WindPro. Det slutligen valda området för exploatering av vindkraft blev Ramakkalmedu, Idukki district, Kerala, Indien. Efter valet av plats valdes tre olika vindturbiner ut för analys; Siemens SWT-3.2-113 3.2 MW, Enercon E-126 4.2MW, och Enercon E-126 7.58MW. Analysen består av flera delar; vindparks-modellering, beräkning av buller-generering från vindkraften, beräkning av årlig energi-generering - Annual Energy Production (AEP), kapacitetsfaktor, vindparkens effektivitet med hänsyn tagen till lagret/dammens variation av bas-last. Resultat har erhållits från alla tre turbinerna och den övergripande slutsatsen är att kombinationen med vatten- och vindkraft med lagring av vatten som pumpas upp vid behov är en tillfredsställande metod för att möta belastningstoppar, vilket valideras av denna uppsats. Nyckelord: pumpade vattenkraftdammar, vindkraftparker, energi lager, förnybar energi. / ABSTRACT Awareness and concern regarding the environmental effects of greenhouse gas emissions and depletion of non-renewable energy sources has increased over the last decades. A considerable development of new technology for renewable energy has occurred globally as an answer to this concern. There has been a major progress in production of electricity and heat generated from solar, wind, ocean, hydropower, biomass, geothermal resources, and biofuels and hydrogen. Consequently, the development of energy storages has become an imperative part, for integration of renewable energy. It is beneficial for the entire supply chain, for dependability and better stability, and for enhanced quality of electrical power. This thesis is exploring an optimal energy design for a system of pumped hydro-wind power plants including storage. Solutions with Pumped Hydro Storages have a great potential for their balancing role necessary for a higher degree of renewable energy sources, RES, in the energy systems because of the intermittent and variable nature of these sources. Tehri pumped hydro storage plant, in Uttarakhand, India is one of the objects studied in this thesis. The systems total efficiency of 93%, calculated from head losses, is discussed as well as wind potential and its impact. Wind data is obtained from National Institute of Wind Energy (NIWE) and analysed using the software tools MATLAB and WindPro. The finally chosen area explored for wind potential is Ramakkalmedu, Idukki district, Kerala, India. After selection of site within the area, three different turbines; Siemens SWT-3.2-113 3.2 MW, Enercon E-126 4.2MW, and Enercon E-126 7.58MW were considered for analysis. The analysis consists of several parts; Wind farm modelling, Noise estimation of Wind Park, estimation of Annual Energy Production (AEP), Capacity factor, Wind park efficiency with respect to the storage/reservoir´s base load variation. Results are achieved for all three turbines. The overall conclusion is that combined hydro and wind power with a pumped storage, is a satisfactory method for bulk energy store to address peak loads, which is validated by this thesis. Keywords: Pumped Hydro, Wind farm, Energy Storage, Renewable Energy.
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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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Resilience-enhancement through Renewable Energy Microgrid Systems in rural El SalvadorAlarcón, Mathias, Landau, Robin January 2019 (has links)
This Master thesis investigates how Renewable Energy Microgrid Systems (REMS) can enhance resilience for a rural grid-connected community in El Salvador. The study examines the optimally resilient design of a grid-connected PV-Wind-Battery hybrid energy system. The optimally resilient system configuration was determined based on energy affordability, defined as minimum net present cost (NPC) and energy reliability, which was defined as a 1% maximum annual capacity shortage. The system modelling and optimisation was performed in the HOMER (Hybrid Optimisation of Multiple Energy Resources) software, where the system was optimised for different scenarios. The results of this study show that REMS can enhance resilience by lowering electricity costs for the community and thus increasing energy affordability. However, the REMS did not manage to make an equally substantial impact on energy reliability, due to the grid performance that proved to be high with few annual power outages. Besides the grid connection, the optimally resilient system was driven entirely by PV energy since it proved to be highly profitable. Wind power and battery storage were excluded from the optimally resilient system since they did not contribute to affordability and the capacity shortage limit was met already from the PV unit and the grid. Furthermore, the results show that self-sufficiency can be provided with REMS from the local energy resources, but that it is unrealistic with current costs due to the high battery prices. The study concludes that REMS should be considered as a legitimate resilience measure in rural El Salvador.
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A Sustainable Future for Wind Energy in SwedenØvereng, Aurora January 2018 (has links)
The 2040 governmental goal of 100 % renewable electricity in Sweden means that there will be a shift in electricity production and a phasing out of nuclear power. This nuclear power has to be replaced by some other source. Wind power is a viable alternative, thanks to its reliability and the abundance of wind in Sweden. However, wind power production requires a large amount of land and carries the risk of disrupting the landscape. Wind energy is therefore often difficult to develop, and when developed it is often in rural areas where it disturbs as few people as possible. This study presents an alternative to rural exploitation, it investigates whether it is possible to produce sufficient wind power to satisfy urban demand within 20 000 meters of the 20 largest cities in Sweden. Firstly, the criteria for areas where wind power can be developed were synthesised. Secondly a numerical model was used to simulate energy demand in TWh considering the future growth in demand and the phasing out of nuclear power. The demand for wind power was then translated into correlating area in km2. Finally, a GIS analysis was conducted to estimate the extent of area suitable for wind power development based on the criteria above and within a 20 000m perimeter from the 20 largest cities in Sweden. The analysis showed that only 35 % of the required area for wind power development fulfilled the criteria within the given perimeter. From the GIS analysis only 940.73 km2 was found to be suitable. From the numerical model, the results showed that for it to be sufficient, there would have to be at least 2687.1 km2 suitable land. The conclusion from this study is that in order to phase out the nuclear power, the majority of the wind power has to be located in the rural areas.
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Improving the performance of hybrid wind-diesel-battery systemsGan, Leong Kit January 2017 (has links)
Off-grid hybrid renewable energy systems are known as an attractive and sustainable solution for supplying clean electricity to autonomous consumers. Typically, this applies to the communities that are located in remote or islanded areas where it is not cost-effective to extend the grid facilities to these regions. In addition, the use of diesel generators for electricity supply in these remote locations are proven to be uneconomical due to the difficult terrain which translates into high fuel transportation costs. The use of renewable energy sources, coupling with the diesel generator allows for the diesel fuel to be offset. However, to date, a common design standard for the off-grid system has yet to be found and some challenges still exist while attempting to design a reliable system. These include the sizing of hybrid systems, coordination between the operation of dissimilar power generators and the fluctuating load demands, optimal utilisation of the renewable energy resources and identifying the underlying principles which reduce the reliability of the off-grid systems. In order to address these challenges, this research has first endeavoured into developing a sizing algorithm which particularly seeks the optimal size of the batteries and the diesel generator usage. The batteries and diesel generator function in filling the gap between the power generated from the renewable energy resources and the load demand. Thus, the load requirement is also an important factor in determining the cost-effectiveness of the overall system in the long run. A sensitivity analysis is carried out to provide a better understanding of the relationship between the assessed renewable energy resources, the load demand, the storage capacity and the diesel generator fuel usage. The thesis also presents the modelling, simulation and experimental work on the proposed hybrid wind-diesel-battery system. These are being implemented with a full-scale system and they are based on the off-the-shelf components. A novel algorithm to optimise the operation of a diesel generator is also proposed. The steady-state and dynamic analysis of the proposed system are presented, from both simulation and an experimental perspective. Three single-phase grid-forming inverters and a fixed speed wind turbine are used as a platform for case studies. The grid-forming inverters adopt droop control method which allows parallel operation of several grid-forming sources. Droop control-based inverters are known as independent and autonomous due to the elimination of intercommunication links among distributed converters. Moreover, the adopted fixed speed wind turbine employs a squirrel cage induction generator which is well known for its robustness, high reliability, simple operation and low maintenance. The results show a good correlation between the modelling, the experimental measurements, and the field tested results. The final stage of this research explores the effect of tower shadow on off-grid systems. Common tower designs for small wind turbine applications, which are the tubular and the lattice configurations, are considered in this work. They generate dissimilar tower shadow profiles due to the difference in structure. In this research, they are analytically modelled for a wind turbine which is being constructed as a downwind configuration. It is proven that tower shadow indeed brings negative consequence to the system, particularly its influence on battery lifetime within an off-grid system. This detrimental effect occurs when power generation closely matches the load demand. In this situation, small frequent charging and discharging cycles or the so called microcycles, take place. The battery lifetime reduction due to these microcycles has been quantified and it is proven that they are not negligible and should be taken into consideration while designing an off-grid hybrid system.
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Anaerobic co-digestion of food and algal waste resourcesCogan, Miriam Lucy January 2018 (has links)
Anaerobic digestion is a key energy and resource recovery technology. This work investigated potential organic waste resources to co-digest with household food waste (HFW) to stabilise the process and future-proof feedstock availability. This included novel feedstock macroalgae (seaweed) waste (SW). Hydrothermal (autoclave) pretreatment was also investigated to optimise energy recovery from HFW and SW. Preliminary experiments investigated the behaviour of HFW co-digested with either a green waste (GW) or paper waste (PW), using a batch-test laboratory scale and systematic approach with a revised waste mixture preparation method. Following preliminary trials, the co-digestion of HFW/SW was investigated using an air-dried SW mixture. Batch experiments to determine the biomethane potential (BMP) at different ratios of HFW to SW were set up. Co-digesting HFW and SW at ratio 90:10 (d.w.) achieved a BMP similar to HFW alone (252±13 and 251±1 cm3 g-1 VS, respectively), and a peak methane yield for HFW:SW (90:10) at day 12 of 69±3% compared to a peak methane yield for HFW at day 19 of 70±3%. Addition of SW optimised the C/N ratio, increased concentrations of essential micronutrients and produced an overall increase in reaction kinetics. Concentrations of SW ≥25%, associated with high sulphur levels, reduced final methane productivity. Analysis of the macroalgae strains L. digitata, U. lactuca and F. serratus from the SW mixture was carried out to compare mono-digestion and co-digestion with HFW at a 90:10 ratio and the effect of autoclave pretreatment at 136°C. Co-digestion had a positive impact on methane yields for U. lactuca and F. serratus, whilst autoclave pretreatment had no significant impact on the SW strains When results were modelled for a 320 m3 anaerobic digester treating 8m3 feed per day the theoretical energy balance showed that optimal energy production from pretreated HFW at 8.09 GJ/day respectively could be achieved. To verify the suitability of using macroalgae, known to readily uptake polycyclic aromatic hydrocarbons (PAH), toxicity tests were used to determine the impact of phenanthrene sorbed by U. lactuca on the AD process. Despite U. lactuca’s ability to biosorb phenanthrene in under 2 hours, no impact on the AD process was observed. Overall, results of this study demonstrated that co-digestion of HFW and SW, at batch laboratory scale, provide a viable and sustainable waste revalorisation solution. In addition, low temperature autoclave pretreatment increased methane production (p=0.002) from the AD of HFW.
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Impact of hybrid distributed generation allocation on short circuit currents in distribution systemsAfifi, Sara Nader January 2017 (has links)
The rapid development in renewable generation technologies and flexible distribution networks requires current infrastructure to be modified and developed to adapt high penetration levels of distributed generation. Existing distribution networks were not initially designed and anticipated to accommodate generators on large scale. Short circuit studies ensure the effectiveness of protection equipment settings and coordination is maintained in case of short circuit, despite any additional distributed generation is connected to the distribution network. This research aims to study and compare the different network fault situations for wind energy systems with induction generators, photovoltaic energy systems, and diesel generators connected to distribution networks. The simulation study will be conducted on the existing IEEE case study systems including 13 bus and 30 bus distribution test systems, using ETAP software. Short circuit analysis will be performed twice to include the ANSI/IEEE and the IEC methods for short circuit currents calculation. Simulated results showed that the wind energy systems have significant impact on the short circuit currents, whereas the photovoltaic energy systems are found to have inconsequential effect. The most moderate solution is found to be a distributed generation mix.
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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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Building capacity for green, just and sustainable futures – a new knowledge field requiring transformative research methodologyRosenberg, Eureta, Ramsarup, Presha, Gumede, Sibusisiwe, Lotz-Sisitka, Heila 1965- January 2016 (has links)
Education has contributed to a society-wide awareness of environmental issues, and we are increasingly confronted with the need for new ways to generate energy, save water and reduce pollution. Thus new forms of work are emerging and government, employers and educators need to know what ‘green’ skills South Africa needs and has. This creates a new demand for ‘green skills’ research. We propose that this new knowledge field – like some other educational fields – requires a transformative approach to research methodology. In conducting reviews of existing research, we found that a transformative approach requires a reframing of key concepts commonly used in researching work and learning; multi-layered, mixed method studies; researching within and across diverse knowledge fields including non-traditional fields; and both newly configured national platforms and new conceptual frameworks to help us integrate coherently across these. Critical realism is presented as a helpful underpinning for such conceptual frameworks, and implications for how universities prepare educational researchers are flagged.
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