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Feasibility Investigation of Floating PV in Hydro reservoirs : A case study on tropical and mediterranean climatic regionsPrasannalal Sheena, Adithi January 2021 (has links)
To secure the growing energy demand due to the rise in population and technological advancements, countries worldwide are looking for alternatives or complementary generation sources to support the existing grid infrastructure and power generating system. The increase in global temperature and climate change forces each country to switch to clean energy production. Among the renewable energy sources, the Floating Photovoltaic (FPV) market is flourishing in various countries. It is a good source of power generation avoiding land constraint issues and adding extra benefits like cooling of panels and reducing evaporation and algal bloom problems of water sources where it is installed. In fact, as a part of a complementary generation, the idea of using unused reservoir water surface of reservoir for the deployment of photovoltaic (PV) is a considerable solution for meeting energy demand. As hydropower and PV are dispatchable and non-dispatchable sources of energy, they can complement each other well. The floating PV and hydropower basics and factors that complement their mutual operation are discussed in this research work with a literature review. Case studies of tropical and mediterranean climatic countries like Myanmar and Albania are analyzed using HOMER Pro. The various challenges associated with this hybrid hydro-floating PV project are evaluated using risk analysis, and the highest risk elements are identified.
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Techno-economic assessment of off-grid PV systems in Eritrean buildings : A case study about apartment buildings in AsmaraYosief, Adonay January 2023 (has links)
Eritrea is experiencing difficulties as a result of its low rate of electricity, together with its expanding population and the significance of green energy in today's world. Due to poor infrastructure and capacity, Asmara's electricity grid is well known for being unreliable, with frequent power outages and load shedding. Due to its location in an area with high solar irradiance, Asmara has a lot of potential for PV. Using a reference hotel building that is based on a case study of a current construction project in the capital Asmara, this thesis has chosen to analyze if implementing PV systems with storage can produce sustainable electricity for residential homes in Asmara. Through a study visit to the current construction project, a load profile is designed. The reference hotel building's 96 apartments had an average daily energy consumption of 1828 kWh and a peak power demand of 207 kW based on the designed load profile. The PV system results showed that none of the PV systems was feasible or economical to implement on the reference hotel building. The PV-hydrogen system required less inverter capacity than the PV-battery system, however the PV-battery system was less expensive and needed less installed PV capacity. The COE for the PV-battery and PV-hydrogen systems was 580 respectively 226 times bigger than Eritrea's existing COE, which is not feasible from an economic standpoint. Additionally, both systems' installed PV capacities were greater than the maximum possible capacity on the reference hotel building.
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Hybrid Renewable Energy Analysis via Homer Pro and ETAP: A case study in VenezuelaTeran Rivero, Carlos Eduardo 01 December 2020 (has links)
AN ABSTRACT OF THE THESIS OFCarlos Eduardo Teran Rivero, for the Master of Science degree in Electrical Engineering, presented on October 15, 2020, at Southern Illinois University Carbondale. TITLE: HYBRID RENEWABLE ENERGY SYSTEMS ANALYSIS VIA HOMER PRO AND ETAP: A CASE STUDY IN VENEZUELA MAJOR PROFESSOR: Dr. Arash Asrari The main objective of this project is to design a realistic hybrid renewable energy system as a micro-grid in order to supply required power to the villages of Coche Island located in Venezuela. Due to the deterioration of Venezuela’s power system, the native people inhabiting in the island frequently find themselves without electricity when there exists a shortage in supply. Considering “Margarita” as an example, the priority of the supply is always considered for the larger communities where there is any relevant issue which will leave the small communities of the Coche Island without any power. The motivation of this thesis is to propose a hybrid micro-grid located in some of the larger villages in the Coche Island using renewable energy resources (RERs) such as photovoltaic and wind turbines such that the community of the corresponding villages can locally generate power in order to cover their basic needs in normal and emergency situations. Toward this end, this thesis presents a hybrid configuration integrated with RERs to address the aforementioned challenges. The suggested frameworks are developed via two different software including ETAP (electrical transient analyzer program) and HOMER (hybrid optimization model for electric renewables), and a comprehensive comparison between the obtained results is provided to validate the effectiveness of the both software in the field of designing hybrid energy systems.
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HYBRID RENEWABLE ENERGY SYSTEM DESIGN - A CASE STUDY IN NEPALDevkota, Menuka 01 December 2021 (has links)
Hybrid energy systems are receiving more popularity in remote areas to provide low-cost electricity by taking advantage of existing electric generation systems and new generations of renewable energy resources. Such hybrid systems will increase reliability and decrease the cost of electricity. Renewable energy sources are gaining more attention due to their flexibility in utilization of locally available resources and their contribution in cleaner energy production. To this end, this thesis scrutinizes the viability of a hybrid renewable energy system (HRES) incorporating wind turbine and photovoltaic (PV) for Kagbeni village located in Nepal. The proposed framework covers both economic and technical aspects. For economic feasibility analysis, the Hybrid Optimization Model for Electric Renewables (HOMER) software is utilized to recognize the optimal size of required assets (i.e., PV module and wind turbine) to be incorporated into the current system. For the technical analysis, Electrical Transient Analyzer Program (ETAP) software is used to virtually model the projected HRES to assess the feasibility of the optimized HRES in operation modality (e.g., power flow, short circuit analysis, and protection coordination). The obtained results confirm that the integration of PV and wind units into the current Kagbeni power grid can lead to an economically feasible and reliable microgrid enhancing the social well-being of Kagbeni’s residents.
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Planejamento de microrredes em sistemas de distribuição de energia elétricaRocha, Kamila Peres 29 August 2018 (has links)
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Previous issue date: 2018-08-29 / O presente trabalho apresenta uma metodologia para o planejamento ótimo de microrredes em redes de distribuição de energia elétrica. Para tanto, é apresentada a formulação dos elementos propostos incluindo sua modelagem técnico-econômica. O objetivo principal é a abordagem das vantagens do sistema de compensação de energia elétrica estipulado pela resolução normativa n◦ 482/2012 da ANEEL, na busca por redução dos custos de energia em um horizonte de planejamento de longo prazo. Para isso, faz-se a utilização da meta-heurística denominada SIA com propósito de obter o dimensionamento otimizado dos elementos da microrrede. A determinação dessa técnica se deve a quantidade de combinações possíveis devido a complexidade do problema apresentado. É traçado, ainda, um comparativo com o método de busca exaustiva para análise das soluções geradas e do tempo computacional requerido para as duas metodologias propostas. O projeto aborda a implantação de fontes de energia renovável eólica e solar e gerador a diesel para análise de estudos de caso para consumidores comercial e residencial. Por último, é realizado um comparativo com resultados provenientes de um software de dimensionamento de microrredes, denominado HOMER Pro R
. / The present work presents a methodology for the optimal planning of microgrids in electricitydistributionnetworks. Forthatreason, theformulationoftheproposedelements includingtheirtechnical-economicmodelingispresented. Themainobjectiveistoapproach the advantages of the net metering stipulated by ANEEL normative resolution 482/2012, in the search for reduction of energy costs in a long-term planning horizon. Therefore, the meta-heuristic called SIA is implemented with the purpose of obtaining the optimized sizing of the elements of the microgrid. The determination of this technique come from the amount of possible combinations due to the complexity of the presented problem. A comparison with the exhaustive search method for the analysis of the generated solutions and the computational time required for the two proposed methodologies is also drawn. The project addresses the deployment of wind and solar renewable energy sources and diesel generator for analysis of case studies for commercial and residential consumers. Finally, a comparison is made with results from HOMER Pro R, a microgrid software.
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Optimization of an energy system in rural ThailandLund, Axel, Malmberg, Mattias January 2023 (has links)
By 2020, Thailand ensured 100% electricity access to its 72 million inhabitants. This was partly done by promoting off-grid energy systems in rural areas instead of using costly grid extensions. Although electricity is ensured for all, future challenges and objectives include- increasing the share of renewable energy and decreasing energy dependence while simultaneously meeting the increasing demand. Off-grid energy solutions for rural areas have been studied in many previous projects. The most optimal energy system concerning cost, resilience, and emissions can be found by quantifying natural resources, estimating electricity consumption, and comparing technologies. This project aims to evaluate how an existing off-grid system can be complemented in the future. This was done by using the optimization program HOMER. The village Ban Wangwon, located in Prachuap Khiri Khan, was for a long time without electricity access due to a law obstructing them from connecting to the grid. This changed when in 2018, households were mounted with PV and BESS. Energy demand in the village was determined in three scenarios based on the World Banks tier system for rural energy and the previous population growth. In addition, the availability of meteorological and natural resources, energy load profile, and price of technology were determined based on the literature review and a field study. According to the results, the most optimal energy system for today's electricity use, Scenario 1, regarding both cost and emissions, was a PV/BESS system. In scenarios 2 and 3, a PV/BESS/Bio configuration proved the most cost-effective, although not optimal regarding emission rates for future energy demand. However, this system sees much lower emissions compared to when diesel generators were included, which makes this suitable for reaching Ban Wangwons requirements. Using a bio generator optimally requires a centralized energy system, requiring settlements with landowners. The biomass fuel considered in this work was pineapple crowns due to the abundance of pineapple factories and farms in the area. After a sensitivity analysis, the most impactful variables proved to be fuel prices, bio generator efficiency, and discount rate. Only one type of solar panel and battery was considered, and the load was assumed to be constant, which hindered the credibility of the results. Future projects could investigate more thoroughly how pineapple waste can be utilized in energy production, how price changes in renewable energy affect the outcome, and how a microgrid would be constructed. The results were considered beneficial in achieving SDGs 1 No poverty, 7 Affordable and clean energy, 11 Sustainable cities and communities, and 13 Climate action. / År 2020 säkerställde Thailand tillgång till el för 100% av sina 72 miljoner invånare. Detta gjordes delvis genom att främja fristående energisystem på landsbygden istället för att använda dyra elnätsförlängningar. Även om el finns tillgängligt för alla, inkluderar framtida utmaningar och mål att öka andelen förnybar energi samt minska energiberoendet samtidigt som efterfrågan på energi ökar. Fristående energilösningar för landsbygden har studerats i många tidigare projekt. Det mest optimala energisystemet gällande kostnader, resilliens och utsläpp kan bestämmas genom att kvantifiera naturliga resurser, uppskatta elförbrukning och jämföra teknologier. I detta projekt utvärderas hur ett redan befintligt fristående system kan kompletteras i framtiden. Detta gjordes med hjälp av optimeringsprogrammet HOMER. Byn Ban Wangwon, belägen i Prachuap Khiri Khan, var länge utan elektricitet på grund av en lag som hindrade dem från att ansluta till nätet. Detta ändrades när hushåll utrustades med PV och BESS år 2018. Energibehovet i byn bestämdes i tre scenarier baserat på the World Banks tier-system för energi på landsbygden samt den tidigare befolkningsökningen. Meteorologiska och naturliga resurser, energianvändningsprofil och teknikpris bestämdes baserat på en litteratur- och fältstudie. Enligt resultaten var det mest optimala energisystemet för dagens elanvädning, Scenario 1, ett PV/BESS system, avseende både kostnader och utsläpp. För de två övriga framtidsscenariorna, Scenario 2 och 3, visade sig en PV/BESS/Bio-konfiguration vara mest kostnadseffektiv, trots att den medför utsläpp. Detta system har dock mycket lägre utsläpp jämfört med dieselelgeneratorer, vilket gör det bra för att nå Ban Wangwons krav. Tillämpning av en biogenerator skulle kräva ett centraliserat energisystem, vilket skulle kräva överenskommelser med markägare. Biomassan som användes i detta arbete var ananasrester på grund av den stora mängden ananasfabriker och plantager i området. Efter en känslighetsanalys visade sig de mest påverkande variablerna vara bränslepris, bio-generatorns effektivitet och diskonteringsräntan. Endast en typ av solpanel och batteri togs i åtanke och elbehovet antogs vara konstant, vilket hindrar trovärdigheten i resultaten. Hur ananasavfall kan användas i energiproduktionen, hur prisförändringar inom förnybarenergi påverkar resultatet och hur ett microgrid skulle kunna konstrueras är alla relevanta frågor för framtida projekt. Resultaten ansågs vara fördelaktiga för att uppnå FN:s hållbarhetsmål 1 Ingen fattigdom, 7 Hållbar energi för alla, 11 Hållbara städer och samhällen och 13 Bekämpa klimatförändringarna.
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Alternative Energy Storage Solutions and Future Scenarios of the Austerland Energy SystemLindblom, 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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Exploring off-grid electricity production in Sweden: Benefits vs costs / Undersöker off-grid elproduktion i Sverige: Fördelar mot kostnaderBjörkman, Jesper, Lundqvist, Simon January 2020 (has links)
Over the past decade, technologies that facilitate household electricity production and storage have seen a rapid development along with a significant cost reduction. Research points to an increased share of household-produced electricity within the existing national grids across the globe. In some cases, self-sufficiency is possible where households are able to decouple from the grid and become independent on their electricity, in other words, go off-grid. Furthermore, this change puts additional pressure on how the electricity system is set up, which, challenges prevailing incumbents to adapt. Depending on the geographical location, circumstances for selfsufficiency varies. Sweden is a country with high seasonal variations with its Northern position, which raises the question of how off-grid households are feasible and, how they can receive traction. To investigate possible changes within large technical systems such as the electricity system, which is a vital part of the society, theories within socio-technical systems have shown much promise. However, these theories often lack the more techno-economic aspect of concrete and future investment costs from a consumer perspective, suggesting an existing research gap. Hence, the purpose of this study is to provide further knowledge regarding off-grid applications in the Swedish Context. This is done by investigating what circumstances could trigger existing electricity consumers to go off-grid. The research process and structure of the report can be interpreted as indiscriminate, however, the study has focused on combining theories surrounding socio-technical changes whilst applying techno-economic modelling to strengthen the work, similar to a dual paper study. Data was collected in the form of a literature review and interviews to provide a holistic representation of off-grid and its nexus to the electricity system. In addition to this, complementing modelling of grid-connected-, prosumer-, and off-grid households were performed. Results point towards a scene where off-grid reaches grid parity within the coming two decades, which, will increase the economic rationale of investing in an off-grid. Opposingly, there is currently no economic rationale in off-grid applications considering the relatively low electricity costs in Sweden as of today. Moreover, conditions show promise if the adopters see beyond economics and, possesses a strong will towards independence. However, implications suggest that the high reliability and low costs of the Swedish electricity grid impedes the ability of new radical innovations to receive traction. Furthermore, this study has contributed by filling the research gap between socio-technical changes and techno-economic projects in regards to electricity systems. Consequently, contributing to the academic field of socio-technical change, it has been shown that the combination of socio-technical change and techno-economic projections is applicable and beneficial. Additionally, it can be argued that the results of this study highlight that the consumer have a greater role in the development of off-grid applications than what the theories suggest. Lastly, the electricity system is a complex mechanism and, to further strengthen the perception of how a relatively new application, as in the case of off-grid, will impact the system, appurtenant suggestions for possible future research within the area are proposed. / Under det senaste decenniet har teknik som underlättar hushållens elproduktion och lagring haft en hastig utveckling tillsammans med en betydande kostnadsminskning. Forskning pekar på en ökad andel hushållsproducerad el inom de befintliga nationella elnäten över hela världen. I vissa fall är självförsörjning möjligt där hushållen kan koppla bort sig från nätet och bli oberoende av sin elförsörjning, med andra ord gå off-grid. Vidare leder en potentiell förändring mot offgrid till ytterligare påtryckningar på hur elsystemet är uppbyggt, vilket utmanar många aktörers sätt att agera. Beroende på geografisk plats så varierar förutsättningarna för självförsörjning. Sverige är ett land med stora säsongsvariationer i och med sin nordliga position, vilket väcker frågan om off-grid hushåll är genomförbara i Sverige och hur de kan skulle kunna etableras. För att undersöka möjliga förändringar inom stora tekniska system som elsystemet, som är en viktig del av samhället, har teorier inom socio-tekniska system visat vara till stor nytta. Däremot saknar dessa teorier emellertid den mer tekno-ekonomiska aspekten av konkreta och framtida investeringskostnader ur ett konsumentperspektiv, vilket antyder ett befintligt forskningsgap. Följaktligen är syftet med den här studien att ge ytterligare inblick om off-grid-applikationer i svenska sammanhang. Vilket har gjorts genom att undersöka vilka omständigheter som kan leda till att befintliga elkonsumenter går off-grid. Forskningsprocessen och strukturen i rapporten kan vara svårtolkat, men studien har fokuserat på att kombinera teorier kring socio-tekniska förändringar samtidigt som man använder teknoekonomisk modellering för att stärka arbetet. Data samlades in i form av en litteraturstudie och intervjuer för att ge en holistisk representation av off-grid och dess koppling till elsystemet. Utöver litteraturstudie utfördes kompletterande modellering av hushållsanslutna, prosumeroch off-gridhushåll. Resultaten pekar mot scenarion där off-grid når nätparitet under de kommande två decennierna, vilket kommer att öka den ekonomiska rationaliteten för att investera i ett off-grid. Det finns det för närvarande inga ekonomiska skäl till att investera off-grid-applikationer med tanke på de relativt låga elkostnaderna i Sverige idag. Förhållandena visar dessutom löfte om att potentiella användare ser förbi ekonomin och har istället en stark vilja mot självständighet. Implikationer tyder emellertid på att det svenska elnätets höga tillförlitlighet och låga pris hindrar nya radikala innovationers förmåga att ta få fäste. Det är argumenterbart att den här studien har bidragit med att fylla forskningsgapet mellan socio-tekniska förändringar och tekno-ekonomiska projektioner inom elsystem. Samtidigt har studien bidragit till det vetenskapliga området kring socio-tekniska visat på möjligheten och fördelen i att kombinera teorier kring socio-teknisk förändring och tekno-ekonomiska förändringar. Dessutom kan det hävdas att resultaten av den här studie visar att konsumenten har en större roll i utvecklingen av applikationer utanför nätet än vad teorierna föreslår. Slutligen är elsystemet en komplex mekanism, och för att ytterligare stärka uppfattningen om hur en relativt ny applikation, som i fallet utanför nätet, kommer att påverka systemet föreslås lämpliga förslag för eventuell framtida forskning inom området.
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