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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Developing a holistic framework to investigate the environmental, social, and economic suitability of tidal stream energy in British Columbia’s remote coastal diesel reliant First Nations Communities

Richardson, Riley L. 06 January 2021 (has links)
This thesis holistically examines the potential for tidal stream turbine (TST) integration to displace diesel generated electricity in remote coastal First Nations communities within the Marine Plan Partnership for the North Pacific Coast region of British Columbia. This thesis utilizes a combination of spatial analysis (GIS Multi-Criteria Decision Analysis) to identify sites; stakeholder engagement to assess TST suitability, bridge knowledge gaps, and understand desired characteristics of community energy systems; and Levelized Cost of Energy (LCOE) analyses for existing diesel and externality included scenarios along with potential TST costs in a candidate community. Results illustrate the need for information within these communities, from resource quantification to characteristics of renewable energy technologies and system feasibility; self-sufficiency as being the primary transition driver; and funding/human resource capacity as being substantial barriers. Within the study region ≈89.8 km2 of feasible resource was identified, with ≈22 km2 of potentially suitable tidal resource in proximity to nine communities. The COVID-19 pandemic resulted in difficulties contacting and arranging interviews with the most suitable communities. Driven by the holistic research mandate requiring community stakeholder engagement to occur in tandem with the economic analyses, Queen Charlotte Village and Skidegate Landing on Haida Gwaii were chosen as the candidate communities, despite not being the most suitable identified communities. The community interviews revealed TSTs as being an acceptable renewable energy technology. Furthermore, the identified site in Skidegate Inlet (SI) was found to have favourable Marine Spatial Planning (MSP) for TST development. Existing diesel generation carries a LCOE of $0.63/kWh, being $0.08-0.14 more per kWh than the literature cited LCOE range for TSTs. The LCOE for CO2 equivalent externalities at current carbon tax prices was found to be an additional $0.02/kWh. Despite having a technically viable peak spring current speed, the SI site was financially unviable for 284 kW of rated capacity across all diesel LCOE scenarios driven by capacity factor (1.62%), high cabling costs (approximately one third of capital costs), and outdated data/assumptions within the Natural Resources Canada Tidal Project Cost Estimation tool used in the tidal LCOE calculations. This work contributes to the progression of tidal energy development on BCs coast along with demonstrating the utility of holistic assessment frameworks for RETs across environmental, social, and economic considerations. The results of this thesis can inform existing MSP efforts in the Marine Plan Partnership for the North Pacific region and the framework developed can be built upon and altered for global use in pursuit of sustainable energy transitions. / Graduate
12

Design optimization of utility-scale PV power plant

Farzaneh Kaloorazi, Meisam, Ghaneei Yazdi, Marzieh January 2021 (has links)
Solar energy market has been rapidly growing in Sweden over the past few years. Älvdalen municipality in central Sweden is investigating the possibility of installing a utility-scale solar power plant. In the present work, we investigate technical design and economic viability of a utility-scale solar power plant in Älvdalen. Several photovoltaics (PV) designs on a 6.6-hectar land are modeled and analyzed. The installation capacity depends on design parameters, such as inter-row spacing distance and orientation.PVsyst simulation tool is used to model several PV system configurations, consisting of both mono- and bifacial PV modules. An extensive sensitivity analysis is performed to get a deep understanding of different design parameters and their effects on performance and production yield of the plant.For PV systems consisting of monofacial PV panels, a set of parameters is investigated, namely, tilt angle of PV arrays, space between rows of the plant. It is observed that an optimized design requires a careful consideration of the two parameters, since they considerably affect the amount of self-shading (shading of PV rows on each other).The optimum design generates more than 5000 MWh electricity annually.Bifacial configurations are designed in two forms: tilted (south or south-east facing) and vertical (east-west oriented). Tiled bifacial systems are basically similar to the monofacial ones. A comparison between the two systems shows that the bifacial gain is between 3 % to 10 %, depending on the tilt angle, inter-row spacing, and PV array height above the ground. Electricity generation per surface area of the vertical east-west bifacial configuration is significantly lower compared to the others and therefore, it is only economically viable together with other land applications, such as agricultural usage.Economical evaluation indicates that for the optimum design the levelized cost of energy (LCOE) is 0.67 SEK/MWh and 0.72 SEK/MWh for monofacial and bifacial system, respectively. Such financial figures are subject to change, depending on the design and financial parameters.
13

Electricity generation from hybrid PV-wind-bio-mass system for rural application in Brazil

SONG, CONGCONG January 2017 (has links)
Electrification of households in rural area and isolated regions plays a significant impact on the balanced economic development. Brazil grows with a high population growth rate, but still parts of rural area and isolated regions do not have the accessibility of electric power. This study focuses on the feasibility study of a hybrid PV-wind-biomass power system for rural electrification at Nazaré Paulista in southeast Brazil. This study was performed by using the hybrid renewable energy system software HOMER. The wind and solar data was collected from Surface meteorology and Solar Energy-NASA, and the biomass data was collected and estimated from other previous studies. The result shows, the hybrid PV-wind-biomass renewable system can meet 1,601 kWh daily demands and 360 kW peak load of the selected rural area. The power system composed of 200 kW PV panels, 200 kW biomass generator, 400 battery banks, and 200 kW converter. All the calculations were performed by Homer and the selection were based on the Net Present Cost (NPC) and Levelized cost of energy (COE). Because of the fossil fuels’ negative impacts on human health and environment, all the energy sources for this system are renewable energies which have less pollution.
14

Feasibility analysis of upgrading the cogeneration unit of George Washington sugar mill in Cuba / Genomförbarhetsanalys av uppgradering av kraftvärmeenheten i sockerbruket George Washington i Kuba

Ginste, Joakim, Partanen, Sascha January 2020 (has links)
Cuba’s government has set a goal to generate 24 percent of the country’s electricity from renewable sources by 2030. The country’s many sugar mills have been identified as key contributors to reach this goal as their cogeneration units have the potential to significantly increase Cuba’s electricity production from biomass by upgrading them to bioelectric plants. This study evaluates the feasibility of upgrading the cogeneration unit of George Washington sugar mill in the province of Villa Clara, Cuba. An energy balance of the proposed upgraded scheme is done to deduce its feasibility from an energy perspective. To deduce the project’s feasibility from a financial standpoint its net present value (NPV), internal rate of return (IRR), discounted payback period (DPP) and levelized cost of energy (LCOE) are calculated. The spared CO2 emissions by integrating more biopower in the Cuban electricity system are calculated from the avoided burning of diesel for electricity production. The impact on Cuba’s energy independence is quantified by calculating the avoided diesel imports. The NPV of the proposed scheme is 64.9 MUSD, the IRR is 25.6 percent which is significantly higher than the set discount rate of 6.5 percent, the DPP is 5.3 years and the LCOE is 0.0533 USD/kWh which is lower than the maximum LCOE set by AZCUBA to 0.14 USD/kWh. The avoided CO2 emissions and imported diesel are estimated to be 110,173 tonnes CO2 and 36,724 tonnes diesel each year, respectively. These indicators suggest that the upgrade of George Washington’s cogeneration unit is feasible.​ / Kubas regering har satt som mål att generera 24 procent av landets elektricitet från förnyelsebara källor till år 2030. Landets många sockerbruk har identifierats som nyckelaktörer för att nå detta mål då sockerbrukens kraftvärmeenhet har potential att öka Kubas elproduktion från biomassa genom att uppgradera dem till bioelektriska kraftverk. Denna studie utvärderar möjligheten att uppgradera kraftvärmeenheten på sockerbruket George Washington i provinsen Villa Clara, Kuba. Först görs en energibalans på det föreslagna uppgraderade systemet för att utläsa dess genomförbarhet ur ett energiperspektiv. För att utvärdera projektets genomförbarhet ur ett finansiellt perspektiv beräknas investeringens nettonuvärde (NPV), interna avkastningsgrad (IRR), diskonterade återbetalningstid (DPP) och energiproduktionskostnad (LCOE). De undvikta CO2 utsläppen genom integrering av mer biokraft i det kubanska elsystemet beräknas från den uteblivna förbränningen av diesel för elproduktion i landet. Effekterna på Kubas energioberoende kvantifieras genom att man beräknar den minskade dieselimporten. NPV i det föreslagna uppgraderade systemet är 64,9 MUSD, IRR är 25,6 procent vilket är betydligt högre än den fastställda diskonteringsräntan på 6,5 procent, DPP är 5,3 år och LCOE är 0,0533 USD/kWh vilket är lägre än det maximala LCOE som fastställts av AZCUBA till 0,14 USD/kWh. De uteblivna CO2-utsläppen och minskningen av importerad diesel beräknas uppgå till 110 173 ton CO2 respektive 36 724 ton diesel varje år. Dessa indikatorer tyder på att uppgraderingen av George Washingtons kraftvärmeenhet är genomförbar.​
15

Vätgasens roll i det regionala energisystemet : Tekno-ekonomiska förutsättningar för Power-to-Power / Hydrogen in a Regional Energy System Context : Techno-economic prerequisites for Power-to-Power

Mattsson, Helen, Lindberg, Jonatan January 2020 (has links)
Alltmer intermittent elkraft byggs idag i Sverige för att öka andelen förnybar el i energisystemet. Detta leder till mer ojämn elproduktion, vilket skapar problem i form av mer volatila och oförutsägbara elpriser. Ett sätt att dämpa effekten av den ökande intermittenta kraften är att använda förnybar vätgasproduktion som lastutjämning. På detta sätt kan vätgasen potentiellt bli en viktig del i den fossilfria energimixen. Att använda vätgas som energilager i en Power-to-Power-applikation (P2P) möjliggör även utnyttjandet av prisarbitrage på elmarknaden. Ett ökat klimatfokus har återuppväckt intresset för hur vätgasproduktion kan göras lönsamt. Några tecken på att satsningar sker är att flera länder satsar stora pengar på vätgastekniker och infrastruktur, där flertalet samarbeten över nationella gränser har etablerats.Denna studie syftar till att undersöka de tekno-ekonomiska förutsättningarna för produktion av förnybar vätgas där lönsamheten av arbitragehandel på elmarknaden Elspot bedöms. Detta innefattar en gedigen granskning av kommersiella tekniker lämpade för Linköpings energisystem, däribland elektrolys, ångreformering och bränslecell. Tre fall konstruerades med olika uppsättningar av ingående komponenter. Sedan utfördes en driftoptimering som tog fram övre och undre prisgränser för produktion respektive konvertering av vätgas mot spotpriset. Optimeringsverktyget Problemlösaren i Excel användes för att få fram dessa gränser. Visual Basic (VBA) användes sedan för att genomföra en lagersimulering som visualiserar lagersaldot för alla årets timmar. För att få fram kostnaden för varje kilogram producerad vätgas användes nuvärdesberäkningen Levelised Cost of Energy (LCOE), vilket även underlättade jämförelsen av de tre fallen. Vilka effekter i form av växthusgasutsläpp de olika anläggningarna medför utvärderades också genom beräkningssättet konsekvensanalys. Där jämfördes effekten i form av nettoutsläpp i koldioxidekvivalenter för integrering av respektive anläggning. Resultaten visar på att det finns kommersiella tekniker som kan integreras med det befintliga energisystemet på ett resurseffektivt sätt, däremot är de ekonomiska förutsättningarna inte lika bra och P2P-lösningarna är idag långt ifrån lönsamma. Anledningen tros vara en kombination av otillräckliga elprisfluktuationer samt låg total systemverkningsgrad (som högst 14%) för samtliga konstruerade fall. De årliga intäkterna från elförsäljningen motsvarar cirka 1 procent av de årliga kostnaderna för anläggningen, och LCOE landade på cirka 1500 kronor. Resultaten från investeringskalkyleringen visar på att en högre utnyttjandegrad leder till en lägre LCOE. Lagersimuleringen visar på att säsongslagring krävs för denna typ av anläggning då fluktuationerna inte är tillräcklig stora på en daglig, veckovis eller månatlig basis. Känslighetsanalys på LCOE och driftoptimeringen visar inte heller på lönsamhetsmöjligheter i P2P-fallen även vid gynnsamma justeringar på parametrarna investeringskostnad, elpris och verkningsgrad. Ur ett klimatperspektiv visar samtliga fall, med ett undantag, på en minskade växthusgasutsläpp i regionen.  Slutsatsen som dras av resultaten från fallstudien är att, trots goda tekniska förutsättningar och positiv inverkan på lokala växthusgasutsläpp, kan en P2P-applikation med vätgaslagring inte göras lönsam i en svensk kontext inom en nära framtid. Däremot visar ett Power-to-Gas-fall potential för lönsamhet, då dess investeringskostnad är mindre samt att systemverkningsgraden är högre. / More and more intermittent electric power is being built in Sweden today to increase the share of renewable electricity in the energy system. This leads to more uneven electricity generation, which creates problems in terms of more volatile and unpredictable electricity prices. One way to dampen the effect of the increasing intermittent power is to use renewable hydrogen production as load shedding. In this way, the hydrogen gas can potentially become an important part of the fossil-free energy mix. Using hydrogen as energy storage in a Power-to-Power application (P2P) also enables the use of price arbitrage in the electricity market. An increased climate focus has rekindled interest in how hydrogen production can be made profitable. Some signs that investments are taking place are that several countries are investing big money on hydrogen technologies and infrastructure, and collaborations across national borders have been established. This study aims to investigate the techno-economic prerequisites for renewable hydrogen production where the profitability of arbitrage on the Elspot market is explored. This comprises a thorough investigation of commercial technologies suited for Linköping’s energy system. Three cases where constructed with different component constellations. Then the operational strategy was optimised which generated a lower and upper price limit for production and conversion of hydrogen with input price data from Elspot. The optimisation tool in Excel was used in order to obtain these price limits. Visual Basic (VBA) was then used for storage simulation in order to get a perception of the storage development through all the hours of the year. The cost of every kilogram of hydrogen produced was then calculated through Levelized Cost of Energy (LCOE), which made the comparison of the three cases easier. The resulting greenhouse gas emissions when integrating the facilities in each case were also evaluated with a so-called impact analysis. The effect was compared in net emissions in carbon dioxide equivalents for an integration of each facility.     The results show that there are commercial technologies that can be integrated with the existing energy system in a resource efficient manner, whereas the economic prerequisites are not as good, where today’s Power-to-Power (P2P) solutions are not profitable. The reason seems to be the combination of insufficient spot price fluctuations and a low system efficiency (14% at best) for each case. The annual revenues correspond to 1 percent of the annual costs and that LCOE lands at about 1500 SEK. A higher utilization percentage of the plant shows a lower LCOE in the investment calculation. The storage simulation indicates that a seasonal storage is needed for this type of facility because of that the spot price fluctuations are not big enough on a daily, weekly or monthly basis. The sensitivity analysis made on the investment calculation and operational strategy also shows that there is no profitability in the P2P cases where parameters regarding investment cost, efficiency and electricity price were set optimistically. The Power-to-Gas case on the other hand shows potential for profitability, all because of lower total investment costs and higher efficiency. All cases except the case with steam methane reforming shows reductions in greenhouse gas emissions when integrated in the regional energy system.   The conclusion that can be drawn from the results in the case study is that, in spite of good technological prerequisites and a positive effect on local greenhouse gas emissions, a P2P-application with hydrogen storage cannot be made profitable in a Swedish context in the near future. However, a Power-to-Gas case shows potential for profitability because of its lesser investment cost and that the system efficiency is higher.
16

Are solar home systems a more financially viable method of electrifying Ghana households?

Radebe, Thandwefika 24 February 2021 (has links)
Africa still has the lowest electrification rates in the world with over 600 million people estimated to be living without access to electricity. What makes the challenge even greater for Africa is that the continent is so sparsely populated that building grid infrastructure is not viable in many cases. However, “pay-as-you-go” solar home systems have provided the continent with the opportunity to correct its electrification deficit. These innovations are not new and many of the costs of operating these systems have reached grid parity when one considers the Levelized Cost of Energy Model. However, these projects still fail to meet institutional investors' bankability criteria. The aim of this study is to try and understand whether solar home systems provide the investor with an opportunity to make a larger risk-adjusted return versus existing grid-based power station projects being considered on the continent. This study uses Ghana's recently built Kpone power station as a case study to complete this analysis. The study also seeks to assess what viability criteria is employed by a broad base of investors if they were to consider funding off-grid power. The study makes use of the Net Present Value model to compare the returns for Kpone and Zola Electric's Infinity solar home system. The study also conducts inductive qualitative analysis to try and ascertain what criteria is assessed for project viability and then builds a conceptual framework for assessing future projects. The study found that Kpone provided a better risk-adjusted return to that of Zola Electric's solar home system, largely because of Kpone's project finance structure reducing the risk of the investment. Our findings also show that investment ticket size, company track record and management track record are among the most highly considered criteria for investments into off-grid companies.
17

Effects of solar parabolic- trough collectors in small- scale district heating systems

Monterrubio, Alejandro January 2022 (has links)
Reducing carbon emissions in our societies requires a massive shift towards renewables. In Sweden, biomass is the dominant source for the district heat production, but growing demand for biomass in other sectors may cause pressure on it. In this context, this thesis explores the possibility to supply heat with solar parabolic thermal collectors to a district heating system in Kosta, a locality in Lessebo municipality, Kronoberg county. The simulations and calculations are based on the locally available hourly data of weather conditions, supply and return temperatures of district heat and heat demand profiles. The energy production as well as the profitability of the installation is evaluated through the calculation of carbon abatement costs, considering that heat supplied from solar collectors spares biomass which can be made available for decarbonating the power sector. Results have shown that a solar installation that cover most of the heat demand during the months of summer, thus 10% of the annual heat demand, can be profitable. This study also investigates different scenarios with increased costs for the biomass resource to simulate the growing pressure around this resource and concludes that with growing costs of the biomass resource, solar application will become more attractive, allowing to make larger solar district heating plants profitable.
18

Cost Comparison of Repowering Alternatives for Offshore Wind Farms

Bergvall, Daniel January 2019 (has links)
The aim of this thesis is to evaluate different repowering alternatives from the viewpoint of increasing power production from existing offshore wind farms (OWF), as some of the first commissioned OWFs are approaching the end of their expected lifetime. The thesis presents a literature review of components and financial aspects that are of importance for repowering of OWFs. In the literature review, risks and uncertainties regarding repowering are also lifted and analysed. The thesis contains a case study on Horns Rev 1 OWF, where three different repowering scenarios are evaluated by technical and financial performance, aiming to compare the cost of repowering alternatives. The design of the case study is based around previous studies of offshore repowering having focused mainly on achieving the lowest possible levelized cost of energy (LCoE) and highest possible capacity factor, often resulting in suggested repowering utilizing smaller wind turbines than the existing ones. In order to evaluate the financial viability of repowering alternatives, the software RETScreen Expert was used to estimate the annual energy production (AEP) after losses and calculate the net present value (NPV) and LCoE for lifetime extension and full repowering utilizing different capacity wind turbines. Input values from the literature as well as real wind resource measurements from the site was utilized to achieve as accurate results as possible. The result of the case study shows that repowering of OWFs have the possibility of providing a very strong business case with all scenarios resulting in a positive NPV as well as lower LCoE than the benchmarked electricity production price. Although the initial investment cost of the different repowering alternatives presented in this thesis still are uncertain to some extent, due to the lack of reliable costs for repowering alternatives, this thesis provides a base for further research regarding the repowering of OWFs.
19

Comparação dos custos de geração de energia elétrica entre tecnologias despacháveis e intermitentes no Brasil

Silva, Leonardo Ribeiro Madeira da 05 May 2017 (has links)
Submitted by Leonardo Madeira (leoribmad@hotmail.com) on 2017-05-24T20:49:04Z No. of bitstreams: 1 Dissertação_Leonardo_Madeira v4 - revEdson VF IMPRESSA.pdf: 497221 bytes, checksum: edd8c6618d1bbcf4135abc1f146a6980 (MD5) / Approved for entry into archive by GILSON ROCHA MIRANDA (gilson.miranda@fgv.br) on 2017-05-29T14:55:52Z (GMT) No. of bitstreams: 1 Dissertação_Leonardo_Madeira v4 - revEdson VF IMPRESSA.pdf: 497221 bytes, checksum: edd8c6618d1bbcf4135abc1f146a6980 (MD5) / Made available in DSpace on 2017-05-30T12:49:39Z (GMT). No. of bitstreams: 1 Dissertação_Leonardo_Madeira v4 - revEdson VF IMPRESSA.pdf: 497221 bytes, checksum: edd8c6618d1bbcf4135abc1f146a6980 (MD5) Previous issue date: 2017-05-05 / This study seeks to evaluate the financial differences of power generation between a huge array of technologies, splitting them in Dispatchable and Intermittent. Tacitly accepted all over the world as a financial tool to compare any kind of technology, the Levelized Cost of Energy, LCOE, might originate inappropriate conclusions assumptions once it considers the life cycle of some power generation source with a homogeneous generation profile. Containing a huge framework of data source and a simple metric, the study puts the Joskow (2011) study into Brazil electric sector context. / Este trabalho busca avaliar as diferenças financeiras de geração de energia entre uma grande gama de tecnologias, separando-as em Despacháveis e Intermitentes. Aceito na grande maioria dos países como instrumento de comparação financeira entre fontes de geração, o Custo Nivelado de Energia (LCOE) também é amplamente utilizado no Brasil. Com base em Joskow (2011) e em dados para empreendimentos brasileiros, mostra-se que esta métrica, o LCOE, pode gerar conclusões equivocadas devido ao fato de considerar, em um ciclo de vida dos projetos, um perfil de geração homogêneo, o que não é compatível com as características de despachabilidade das diversas fontes.
20

Economic Modelling of Floating Offshore Wind Power : Calculation of Levelized Cost of Energy

Heidari, Shayan January 2017 (has links)
Floating offshore wind power is a relatively new technology that enables wind turbines to float above the sea level, tied by anchors at the seabed. The purpose of this work is to develop an economic model for the technology in order to calculate the total cost of a planned wind farm. Cost data are retrieved from reports and academic journals available online. Based on these data, a model in Microsoft Excel is developed which calculates the Levelized cost of energy (LCOE) for floating wind power plants as a function of several input values. As an addition to this model, financing offshore projects are described using literature study and by doing interviews with three major companies, currently investing in offshore wind. As a result, the model allows the user to calculate Capital expenditures, Operating expenditures and LCOE for projects at any given size and at any given site. The current LCOE for a large floating offshore wind farm is indicated to be in the range of 138-147 £/MWh. The outline from interviews was that today there is no shortage of capital for funding wind projects. However, in order to attract capital, the governmental regulatory of that market has to be suitable since it has a crucial impact on price risks of a project.

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