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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.
151

Techno-economic analysis of energy storage integration for solar PV in Burkina Faso

Abid, Hamza January 2019 (has links)
Electrification in rural areas of West African countries remain to be a challenge for the growth of the region. The Economic Community of West African States (ECOWAS) has set a target of 2030 to achieve 100% electrification in all member countries. Burkina Faso is one of the least electrified countries in the world, where only 9 % of the rural population has access to electricity. This study presents a conceptualization of techno-economic feasibility of pumped hydro storage (PHS) and electric batteries with solar photovoltaics (PV) in the context of Burkina Faso. The results are explored for an off grid standalone PV plus storage system for a rural setting and a grid connected PV system for an urban setup. The least cost configurations for both the cases are determined using HOMER (Hybrid Optimization Model for Electric Renewables). The results indicate the need of extended solar penetration in Burkina Faso in response to the challenges of low electrification rates in the country. Adding more PV to the present electricity mix of Burkina Faso could drive down the cost of energy by 50 % compared to the present grid electricity prices by making cheap electricity available to the local population. Adding PHS to grid connected PV leads to a cost reduction of 8% over a lifetime of 25 years which does not provide enough motivation for the high investments in storage at present. Policy interventions that allow stacking up of revenues and benefits of storage are needed to make it more competitive. PV plus pumped hydro storage remains the optimal system architecture as compared to PV plus electric batteries for off grid standalone systems provided the geographic availability of lower and upper reservoirs. The capital cost of PV remains to be the most dominating factor in the cost of optimal system for both the urban and the rural cases, and driving down the costs of PV would have the most positive effect for increased electricity access in the country. / Elektrifiering i landsbygdsområden i västafrikanska länder är fortfarande en utmaning för tillväxten i regionen. Ekonomiska gemenskapen i Västafrikanska stater (ECOWAS) har satt upp ett mål 2030 att uppnå 100% elektrifiering i alla medlemsländer. Burkina Faso är ett av de minst elektrifierade länderna i världen där bara 9% av landsbygdsbefolkningen har tillgång till el. Denna studie presenterar en konceptualisering av teknisk ekonomisk genomförbarhet för pumpad vattenkraftlagring (PHS) och elektriska batterier med PV (photovoltaics) paneler i samband med Burkina Faso. Resultaten undersöks med avseende på ett fristående fristående PV plus lagringssystem för landsbygden och ett nätanslutet PV-system för en stadsinstallation. De lägsta kostnadskonfigurationerna för båda fallen bestäms med hjälp av HOMER (Hybrid Optimization Model for Electric Renewables). Resultaten visar på behovet av utökad solpenetrering i Burkina Faso som svar på utmaningarna med låga elektrifieringshastigheter i landet. Att lägga till mer PV till den nuvarande elmixen av Burkina Faso skulle kunna sänka energikostnaderna med 50% jämfört med de nuvarande elpriserna för nätet genom att göra billig el tillgänglig för lokalbefolkningen. Att lägga till PHS till nätansluten PV leder till en kostnadsminskning på 8% under en livslängd på 25 år som inte ger tillräcklig motivation för de stora investeringarna i lagring för närvarande. Politikåtgärder som möjliggör stapling av intäkter och fördelar med lagring behövs för att göra det mer konkurrenskraftigt. PV plus pumpad hydro förblir den optimala systemarkitekturen jämfört med PV plus elektriska batterier för fristående nät utanför nätet förutsatt geografisk tillgänglighet av nedre och övre reservoarer. Kapitalkostnaden för PV är fortfarande den mest dominerande faktorn i det lägsta kostnadssystemet för både stads- och landsbygdsfall och att köra ner PV-kostnaderna skulle ha den mest positiva effekten för ökad elåtkomst i landet.
152

[en] PROPOSAL OF PUBLIC POLICIES FOR INSERTING PUMPED STORAGE HYDROELECTRIC PLANTS IN BRAZIL: A MULTICRITERIA APPROACH / [pt] PROPOSIÇÃO DE POLÍTICAS PÚBLICAS PARA INSERÇÃO DE USINAS HIDRELÉTRICAS REVERSÍVEIS NO BRASIL: UMA ABORDAGEM MULTICRITÉRIO

GUILHERME VIEIRA COSENTINO 21 November 2022 (has links)
[pt] A inserção de sistemas de armazenamento de energia é uma tendência global observada no cenário de diversificação energética de vários países no mundo. Considerando a predominância da geração hídrica centralizada na matriz elétrica brasileira, as Usinas Hidrelétricas Reversíveis possuem uma tendência à utilização dentro do Sistema Interligado Nacional (SIN). Entretanto, tal processo de inserção deve considerar as possíveis alterações no marco regulatório advindas de novas políticas regulatórias para o setor elétrico brasileiro. A seleção destas políticas deve considerar diversos critérios e várias dimensões. Além disso, a política escolhida deve considerar uma Análise de Impacto Regulatório para sua efetividade. O objetivo principal desta dissertação é propor um modelo de seleção e avaliação dessas políticas, utilizando um processo de análise de impacto regulatório (AIR), com o auxílio de métodos multicritério de apoio à decisão (MCDM). O modelo definido foi proposto em seis etapas: definição do problema regulatório; determinação do framework regulatório; mapeamento das alternativas de ação; análise benefício-custo conduzida com o método AHP; seleção da política preferida com o método fuzzy-TOPSIS e monitoramento e avaliação desta política. A modelagem foi aplicada para as seguintes cinco políticas definidas: criação de um mercado de capacidade; criação de um mercado de flexibilidade; implementação de um leilão multiatributos; implementação de um leilão de capacidade; e adoção de uma política de incentivos. Os resultados foram comparados com algumas referências, confirmando a aplicabilidade da metodologia e indicando que o desenvolvimento do modelo proposto preencheu lacunas na literatura referente às aplicações de abordagem multicritério para políticas energéticas. / [en] The insertion of the energy storage systems is a global trend observed in the energy diversification scenario of several countries in the world. Considering the predominance of centralized hydroelectric generation in the brazilian electric matrix, Pumped Storage Hydroelectric Plans tend to be used within the National Interconnected System (SIN). However, such insertion process must consider the new changes in the regulatory framework arising from Brazilian regulatory policies for the sector. The selection of these policies must consider several and several dimensions. In addition, the chosen policy must consider a Regulatory Impact Analysis for its own. The main objective of this dissertation is to propose a model for the selection and evaluation of these policies, using a Regulatory Impact Analysis (RIA) process, with the aid of multicriteria decision making methods (MCDM). The defined model was proposed in six stages: definition of the regulatory problem; determination of the regulatory framework; mapping of action alternatives; benefit-cost analysis with the AHP method; selection of preferred policy with the fuzzyTOPSIS method and monitoring and evaluation of this policy. The modeling was applied to the following five policies: creating a capacity market; creation of a flexibility market; implementation of a multi-attribute auction; implementation of a capacity auction; and adoption of an incentive policy. The policies were compared with some references, confirming the applicability of the methodology and indicating the development of the proposed model, gaps in the literature regarding the applications of multicriteria for energy.
153

Pulse Compression in a Mid-infrared Synchronously Pumped Optical Parametric Oscillator

Kurti, R. Steven, Jr. 20 January 2005 (has links)
No description available.
154

Evaluation of available electricity storage technologies and the possible economic gain for Växjö Energi / Analys av tillgängliga energilagringsteknologier och lönsamhetsmöjligheten för Växjö Energi genom ellagring

Sheibeh, Rasam January 2021 (has links)
As the renewable energy sources are finding more place in the energy generation technologies,the Swedish energy market is also undergoing transformations. Renewable energy sources inthe energy generation system brings more volatility and price fluctuations which can mean challenges and opportunities. Svenska Kraftnät, as the authority responsible for safety and stability of Swedish transmission system, addresses the challenges with higher shares of renewable energy sources to some extent with more frequency stabilizing solutions but the electricity prices are controlled by free market which is led by NordPool. Växjö Energi is a state-owned company with energy generation facility of combined heat and power, operating in SE4 area of electricity market. As SE4 is the region affected the most with the price fluctuations, Växjö Energi is interested in analyzing the possibility of increasing their profit by utilizing the available energy storage technologies in the market in long term energy storage applications. The available energy storage solutions and the ones under development have each, their own pros and cons that this project attempts to go through from economical, technical, and sustainability perspective. Technologies such as compressed air energy storage and pumped hydro are more mature and there are more data available about them with less uncertainty. However, technologies such as gravity power module are new and there is not much information so the uncertainty of data is higher. A model has been developed in this project from earlier work of other researchers, to measure the highest possible profit for each energy storage technology in a specific price time series through electricity storage. The result suggests the compressed air energy storage, gravity power module, and pumped thermal electricity storage are the interesting technologies for further study. We show through this work that their costs and possible revenues are comparable. The future work on this subject is to include the suggested technologies with more details and adaptation to Växjö Energi conditions for more detailed and reliable results. / Förnybara energikällor får en större andel av energiproduktionsteknikerna samtidigt som den svenska energimarknaden genomgår förändringar. Förnybara energikällor i energiproduktionssystemet ger mer volatilitet och prisfluktuationer som kan innebära både utmaningar och möjligheter. Svenska Kraftnät, den ansvariga myndigheten för säkerhet och stabilitet i det svenska överföringssystemet, hanterar utmaningarna relaterade till högre andel förnybara energikällor med mer frekvensstabiliserande lösningar men samtidigt styrs elpriserna av den fria marknaden som leds av NordPool. Växjö Energi är ett statligt företag med energiproduktionsanläggning för kraftvärme som verkar inom SE4-området på elmarknaden. Eftersom SE4 är den region som drabbas mest av prisfluktuationerna, är Växjö Energi intresserad av att analysera möjligheten att öka deras vinst genom att använda tillgängliga energilagringsteknologier på marknaden för energibitrageapplikationer. De tillgängliga energilagringslösningarna och de som är under utveckling har alla sina egna fördelar och nackdelar som detta projekt analyserar ur ett ekonomiskt-, tekniskt- och hållbarhetsperspektiv. Teknik som tryckluft, energilagring och vattenkraft är mer mogna och det finns mer information om dem samt mindre osäkerhet. Däremot, energilagringsystem såsom gravitationskraftmodul är ny vilket gör att den tillgängliga informationen är begränsad och följaktligen mer osäker. Detta projekt har utvecklat en modell utifrån tidigare forskning i området, för att mäta högsta möjliga vinst för varje energilagringsteknik under en specifik tid genom ellagring. Resultatet antyder att lagring av tryckluft, tyngdkraftsmodul och pumpad termisk ellagring är de intressanta teknikerna för vidare studier. Genom detta arbete visar vi att deras kostnader och eventuella intäkter är jämförbara. Vidare studier utifrån detta projekt är att studera de föreslagna teknikerna djupare med hänsyn till Växjö Energis förhållanden för mer detaljerade och tillförlitliga resultat.
155

Management of Artificial Recharge Wells for Groundwater Quality Control

Wilson, L. G. 23 April 1971 (has links)
From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / Recharge wells may be used in various problems relating to chemical water quality because of the phenomenon of in-aquifer mixing. This paper reviews specific recharge well-mixing techniques of possible utility in underground mixing operations for nitrate control. Illustrative data from field studies at a recharge site near Tucson, Arizona are presented. Both single- and 2-well types of mixing were investigated. In single-well operations, effluent recharge and pumping of the subsequent mixture occur at the same well. Differences in chlorine ion levels were used to distinguish between recharge effluent and native groundwater. Undiluted effluent was discharged in single-well operations until a pumped volume ratio of about 0.4 was attained. Dilution increased steadily with increased pumping and the relative concentration versus pumped volume curve was s-shaped. Seven-day pauses after effluent recharge resulted in immediate pumping of almost completely diluted water, probably because groundwater movement swept the effluent beyond the pumping unit during the pause. With 2-well pumping, the chlorine breakthrough curve reached a constant level at about 13 days and was close to that of the pause-type, single-well regime.
156

The Compartmented Reservoir: Efficient Water Storage in Flat Terrain Areas of Arizona

Cluff, C. B. 15 April 1978 (has links)
From the Proceedings of the 1978 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 14-15, 1978, Flagstaff, Arizona / The compartmented reservoir is presented as an efficient method of storing water in areas of Arizona having a relatively flat terrain where there is a significant water loss through evaporation. The flat terrain makes it difficult to avoid large surface- area-to-water-volume ratios when using a conventional reservoir. Large water losses through evaporation can be reduced by compartmentalizing shallow impervious reservoirs and in flat terrain concentrating water by pumping it from one compartment to another. Concentrating the water reduces the surface-area-to-water-volume ratio to a minimum, thus decreasing evaporation losses by reducing both the temperature and exposure of the water to the atmosphere. Portable, high-capacity pumps make the method economical for small reservoirs as well as for relatively large reservoirs. Further, the amount of water available for beneficial consumption is usually more than the amount of water pumped for concentration. A Compartmented Reservoir Optimization Program (CROP-76) has been developed for selecting the optimal design configuration. The program has been utilized in designing several systems including several in Arizona. Through the use of the model, the interrelationship of the parameters have been determined. These parameters are volume, area, depth, and slope of the embankment around each compartment. These parameters interface with the parameters describing rainfall and hydrologic characteristics of the watershed. The water -yield model used in CROP-76 requires inputs of watershed area, daily precipitation and daily and maximum depletion. In addition, three sets of seasonal modifying coefficients are required either through calibration or estimated by an experienced hydrologist. The model can determine runoff from two types of watersheds, a natural and /or treated catchment. Additional inputs of CROP-76 are the surface water evaporation rate and the amount and type of consumptive use.
157

Specifika nastavení řešiče v systému Ansys Fluent pro nízké tlaky v EREM / Specifications of the Ansys Fluent Solution Solver for low pressures in EREM

Šimík, Marcel January 2017 (has links)
This thesis is focused on electron microscopy which issue is discussed at the beginning of work. The main attention is dedicated to the Environmental electron microscope, especially the differentially pumped chamber, which the thesis deals with. There is a production of an experimental chamber for analysis of shock waves on going therefore main goal of this thesis was to analyze the flow pattern in this chamber. Using the Ansys Fluent program, simulations of the characteristic flow that arises from the pumping of the vacuum chambers namely the ultrasonic flow at low pressures on which the most suitable turbulent module was applied as well as the degree of discretization was performed. The final analysis of this flow pattern is primarily focused on the localization of the shock wave which experimental evidence is to be lodged by shadow optical method as a part of the new concept of the chamber. The basis for the simulation of the chamber was taken over by Dr. Danilatos, with which the results were compared.
158

Posouzení výhodnosti výstavby přečerpávací vodní elektrárny velkého výkonu v lokalitě Cukrová bouda, okres Šumperk / The assessment of advantages of construction of large hydroelectric power plants in the area of Cukrova bouda, district Sumperk

Knápek, Michal January 2012 (has links)
The subject matter of the master´s thesis is, in particular, an evaluation of the advantageousness of the construction of a pumped-storage hydroelectric power station in the vicinity of Cukrová Bouda. In the master´s thesis introduction the utilisation of pumped-storage hydroelectric power stations in providing reserve power generation to the operator of a power transmission system is discussed. The thesis then focuses on a technical design solution where two alternatives are drawn up for which the nominal parameters of individual designs for a pumped-storage hydroelectric power station are specified. The following part deals with the impact of the structure and the plant’s subsequent operation on the environment. A further key part is the determination of investment and subsequent operating costs and an evaluation of the plant according to economic pointers. The final part of the master´s thesis contains a SWOT analysis and an assumed programme of works for the plant’s preparation and actual construction. The conclusion contains an overall evaluation.
159

Alternative Energy Storage Solutions and Future Scenarios of the Austerland Energy System

Lindblom, Jennie January 2022 (has links)
The project Austerland Energi at the eastern tip of the island of Gotland called Östergarnslandet was started as a response to the larger project Omställning Gotland funded by the Swedish government as an effort for a pilot project to convert to renewable energy to reach zero CO2-emissions for the country in 2045. The current plan for the Austerland energy system is a solar PV and wind production base with energy storage in the form of batteries and hydrogen which also can be used as vehicle fuel. The system will also continue to be connected to the grid and the annual electricity consumption for the area is 3.4 GWh, including both households and agricultural activities. The energy system has been modeled by Energenious, a company based in Berlin, Germany, who recommended a battery storage and electrically driven vehicles. The total investment cost of which was 30.099 MSEK and the operation and maintenance cost was 2,780 kSEK/year and the emission rate was 138 ton/year.  The yearly global horizontal irradiance is approximately 1,060 kWh/m2 at the location, the average wind speed is 7.5-8.5 m/s at 100 m hub height, but the wind turbine would have to be lower because of the Östergarnslandet being a protected area for the beautiful scenery. The heat production is mostly individual for each household or farm with either heat pumps or biomass boilers. There are no options for hydropower at the location and there is a desalination plant and a water treatment facility which provides the households and farms with drinking and irrigation water. The alternative energy storage solutions investigated in this thesis includes Flywheel, Redox flow battery, Pumped hydro, Deep Sea pumped hydro, Supercapacitors, Compressed air energy storage and Thermal energy storage. The first three of which were included in the models of the system. For the Future scenario changes of the energy consumption, the patterns of change for the households were based on national and regional trends the last 25 years.  The Austerland energy system was modeled using the software Homer Pro, where the base case of using batteries and batteries together with hydrogen storage was analyzed. The batteries were then switched to flywheels, a redox flow battery and a pumped hydro system respectively and analyzed with and without the hydrogen storage. The results showed that the recommended storage solution was still the batteries since the flywheel storage has too short storage duration, the flow battery storage is more expensive, and the pumped hydro storage has a complicated installation process. However, the recommended size of the batteries was half that of the recommended size provided by the Energenious models and the results also showed that the system would be suitable for a future change of the consumption patterns.  Lastly, the sustainability analysis showed that all the alternative energy storage devices have a slightly less CO2-emission rate, but none of the systems had a emission rate as low as that calculated by Energenious. However, when considering any of the components in an energy system, a more thorough investigation of environmental and social issues of the production process should be made. The investigation should include studying working conditions, wages, suspicions about child labour, process waste streams and other emissions streams and ethical values at the production company. / Projektet Austerland Energi är lokaliserat på ön Gotlands östra spets kallat Östergarnslandet. Projektet startades som ett efterfrågat initiativ genom det större projektet Omställning Gotland vilket är finansierat av den svenska regeringen. Omställning Gotland är för ett pilotprojekt för att ställa om till förnybar energi i landet och för att nå netto noll CO2-utsläpp i landet år 2045. Den nuvarande planen för Östergarns energisystem är en solcells- och vind produktions bas med energilagring i form av batterier och vätgas vilket också kan användas som fordonsbränsle. Systemet kommer även fortsättningsvis att vara anslutet till det lokala elnätet och den årliga elförbrukningen för området är 3.4 GWh inklusive både hushåll och lantbruksverksamhet. Energisystemet har modellerats av Energenious, ett företag baserat i Berlin, Tyskland, som rekommenderade batterilagring och elfordon snarare än att använda vätgas. Den totala investeringskostnaden var beräknad till 30,099 MSEK och drift- och underhållskostnaden var 2,780 kSEK/år och CO2-utsläppen var 138 ton/år.  Den årliga solinstrålningen på Östergarn är cirka 1,060 kWh/m2, medelvindhastigheten är 7.5-8.5 m/s vid 100 m navhöjd, men vindkraftverket måste vara lägre än så eftersom Östergarnslandet är ett skyddat område på grund av det vackra landskapet. Värme förses mestadels individuellt för varje hushåll eller gård med hjälp av antingen värmepumpar eller värmepannor som använder biomassa. Det finns ingen möjlighet för vattenkraft på denna del av Gotland men det finns en avsaltningsanläggning och en vattenreningsanläggning som förser hushållen och gårdarna med dricksvatten och vatten för bevattnings. De alternativa energilagrings lösningar som undersöks i denna avhandling inkluderar svänghjul, redox flödesbatteri, ett pumpkraftverk antingen på land eller till havs, superkondensatorer, trycklufts lagring och lagring av termisk energi. De tre förstnämnda alternativen ingick i modelleringen utförd i detta arbete. För undersökningen av framtida energiförbruknings förändringar, undersöktes utvecklingen för hushållen på nationella och regional nivå under de senaste 25 åren. Austerlands energisystem modellerades med hjälp av programvaran Homer Pro, där originalmodellen med endast eller batterier tillsammans med vätgaslagring analyserades. Batterierna byttes sedan till svänghjul, ett redox flödesbatteri respektive ett pumpkraftverk och analyserades med och utan vätgaslagringen. Resultaten visade att den rekommenderade lagringslösningen fortfarande var batterierna eftersom svänghjulet har för kort lagringstid, flödesbatteriet är för dyrt och pumpkraftverket har en mycket mer komplicerad installationsprocess. Den rekommenderade storleken på batterierna visade sig dock vara hälften av den rekommenderade storleken från Energenious-modellerna och resultaten visade också att systemet kommer vara lämpligt för den beräknade framtida konsumtionen. Slutligen visade hållbarhetsanalysen att alla alternativa energi lagringstyper har en något lägre koldioxidutsläpp, men inget av systemen hade en så lågt utsläpp som beräknat av Energenious. När någon av komponenterna i ett energisystem övervägs bör dock en mer grundlig undersökning av miljömässiga och sociala frågor i produktionsprocessen göras. Undersökningen bör omfatta arbetsvillkor, löner, misstankar om barnarbete, avfallshantering och andra utsläpp under produktionsprocessen och etiska värderingar hos produktionsföretaget.

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