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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.
61

Monetär värdering av effekter från transportprojekt : En fallstudie med fokus på Trafikverkets väginvesteringar

Bengtsson, Anna January 2015 (has links)
Ett företag som ska välja mellan olika investeringsalternativ kan använda sig av nettonuvärdesmetoden för att beräkna vilken investering som anses mest lönsam. För att genomföra uträkningen prognostiseras framtida positiva kassaflöden som investeringen förväntas generera. Nettonuvärdesmetoden kan även användas vid bedömningar av infrastrukturinvesteringar men för den offentliga sektorn är de positiva kassaflödena inte lika frekventa i investeringsprocessen. För den offentliga sektorn är det istället befolkningens nytta av en investering som värderas. Nyttan är från början kvalitativ och värderas monetärt med hjälp av kalkylvärden, kalkylprinciper, trafikprognoser och andra verktyg. En monetär värdering av nytta gör att en nettonuvärdesuträkning blir möjlig. För att genomföra omformuleringen används en metod som kallas Cost-Benefit Analysis. Genom metoden identifieras de kvalitativa effekterna av en investering för att de sedan ska kunna kvantifieras. Studiens undersökningsenhet är Trafikverket som utvecklar och underhåller det Svenska transportsystemet. Studien har identifierat vilka värden Trafikverket kvantifierar i sin nettonuvärdesuträkning, vilka faktorer som ligger bakom värderingen och hur kvantifieringen går till. Det är nyttan i form av sparad tid, trafiksäkerhet och konsekvenser för miljö som kvantifieras. Undersökningen har skett genom insamling av teori i form av vetenskapliga artiklar samt rapporter och den empiriska utgångspunkten har varit de rekommendationer och den beräkningsmetodik som Trafikverket använder sig av vid den monetära värderingen. Värderingen av nytta som genereras av en investering är beroende av befolkningens betalningsvilja för ökad nytta. Det är den betalningsviljan som är grunden för de rekommendationer som Trafikverket följer. Resultatet har visat de faktorer som är grunden för värderingen, vilka värden som kvantifieras och hur kvantifieringen är möjlig, för att Trafikverket ska kunna använda nettonuvärdesmetoden för att göra en bedömning angående ett investeringsalternativ. / When a company decides which project to invest in among different alternatives they can use the net present value method. The method uses the expected generation of cash flow from the different investments in order to determine which investment would generate the most profit for the company. The net present value method can also be used by the public sector to decide between different projects. The public sector does not consider the same aspects with regards to cash flows as companies. The public sector calculates future cash flows in terms of benefits and costs for the countries population. The benefits from an investment are qualitative from the start and need to be monetized in order to be used in the net present value calculation. The quantification of the qualitative effects is accomplished though calculation values, calculation principles, traffic forecasts and other applications. To be able to facilitate the transformation the public sector can use a method called Cost-Benefit Analysis. The method makes it possible to identify the qualitative effects of an investment and then translate the effects to quantity values. A case study has been made with the Swedish Transport Administration as investigation unit, which is the organization that develops and maintains the Swedish transportation system. The case study has resulted in an identification of which values the Swedish Transport Administration decides to monetize, which aspects the values depends on and how the monetization is made. It is the benefits of saved travel time, value of a statistical life and environmental effects that are monetized. The theoretical part of the study is composed of scientific journals and reports. The empirical part of the study has been founded in the different recommendations and calculation methods which the Swedish Transport Administration uses to perform the monetization. The valuation of the benefits generated from a project is dependent on the populations’ willingness to pay for it. It is the willingness to pay which is the foundation of the recommendations which the Swedish Transport Administration adhere to. The results have shown the different aspects which are the foundation for the valuation. The results have also shown which values are quantified and how the quantification is possible to enable the Swedish Transport Administration to use the net present value method in order to judge different investment alternatives.
62

Studies of economic viability of photovoltaic micro and minigeneration considering ANEELâs regulatory resolution number 482 / Estudos da viabilidade econÃmica da micro e minigeraÃÃo fotovoltaica à luz da resoluÃÃo normativa n 482 da ANEEL

Paulo Marcos Carneiro Teles Filho 27 October 2015 (has links)
This work consists in performing an economic study regarding the implementation of photovoltaic micro and minigeneration in the Northeast region of Brazil, considering the Compensation System for Electric Energy. A thorough literature review is presented focused on concept of solar energy, as well as potential applications and inherent advantages and disadvantages. In order do understand the current market scenario comprising photovoltaic generation in Brazil, the costs associated to several system components and involved taxes are evaluated. In order to assess solar resources in a given study region and evaluate the amount of energy that generated during one year, three examples regarding systems rated at 1.5 kW, 100 kW and 1 MW are presented and discussed. Based on key parameters such as initial investments, generation rate, operation and maintenance costs, and energy generated, the Net Present Value (NPV) and the Internal Rate of Return are calculated of each aforementioned case. It can be seen that a negative NPV is obtained for the 1.5-kW systems, while the positive values exist for the 100-kW and 1-MW ones. Besides, the Internal Rate of Return (IRR) is lower than the financial ends for the 1.5-kW system and higher for the remaining others. / O presente trabalho trata de realizar um estudo econÃmico de sistemas fotovoltaicos de micro e minigeraÃÃo para a regiÃo Nordeste do Brasil, considerando o Sistema de CompensaÃÃo de Energia ElÃtrica. Uma revisÃo literÃria aprofundada à apresentada e focada no conceito de energia solar, bem como suas potenciais aplicaÃÃes e as vantagens e desvantagens inerentes. Para entender a situaÃÃo atual do mercado com relaÃÃo à energia fotovoltaica no cenÃrio brasileiro, sÃo apresentados preÃos de aquisiÃÃo das componentes que compÃem o sistema solar e exemplificados os impostos envolvidos. A fim de mensurar o recurso solar da regiÃo de anÃlise e avaliar a quantidade de energia elÃtrica gerada em um ano, sÃo apresentados e discutidos trÃs exemplos de sistemas com as potÃncias de 1,5 kW, 100 kW e 1 MW. A partir dos dados de investimentos iniciais adotados, taxa de geraÃÃo, custos de operaÃÃo e manutenÃÃo, energia gerada sÃo calculados o Valor Presente LÃquido e a Taxa Interna de Retorno para cada sistema escolhido, tendo como resultados o VPL negativo para o sistema fotovoltaico de 1,5 kW e positivo para os sistemas de 100 kW e 1 MW, e a TIR inferior a taxa de atratividade financeira para o sistema de 1,5 kW e superior para os demais sistemas fotovoltaicos analisados.
63

Vliv kogenerace na energetiku a trh s elektrickou energií v ČR / Cogeneration influence on power industry and power market in Czech Republic

Dudáš, Michal January 2014 (has links)
The main goal of this master’s thesis is to find out the impact of future development in combined heat and power technologies, especially the impact on power market in Czech Republic regarding to historical development of photovoltaics and subsidy policy. There are three scenarios of installed power growth designed including calculations of renewable energy source financial fee as well as overall evaluation. The paper also deals with current status of combined heat and power technologies in Czech Republic, European Union and USA as well as legislature framework of CHP in Czech Republic and EU. There are also kinds of state grants described. In economical part of the paper there are NPV’s of particular cogeneration units calculated. The calculations were made both with current investment costs and reduced investment costs.
64

Optimalizace životního cyklu transformátoru 110/22 kV / Optimization of the lifecycle transformer 110/22 kV

Suk, Jiří January 2017 (has links)
The aim of the thesis is to describe the situation in transformation 110/22 kV in distribution area E.ON East. Next to describe the current practice in the replacement of 110/22 kV transformers and mention the possibilities of replacing the machines at the end of their lifecycle with respect to the development of the load of the individual transformer stations in the distribution area. An integral part of the thesis is also the economic evaluation of premature replacement of transformers from two different perspectives. The next point is to look at the current possibilities in the lifecycle lengthening of these devices and to suggest a method for monitoring the state of paper insulation to estimate the remaining lifetime of the transformer. The last point is the evaluation of the transition of a significant customer from a voltage level of 22 kV to a voltage level of 110 kV, including related technical and economic issues.
65

Påverkande faktorer vid initiativ till nya investeringar och valet av kalkylmetod : En komparativ flerfallstudie av sexton svenska elnätsföretag

Mohamed Ibrahim, Munira, Värnlund, Matilda, Zetterström, Susanna January 2020 (has links)
Titel: Påverkande faktorer vid initiativ till nya investeringar och valet av kalkylmetod - En komparativ flerfallstudie av sexton svenska elnätsföretag Bakgrund och problemdiskussion: Tillväxten i samhället och förändrade behov har lett till högre krav på svenska elnätsföretag och elnätet. Det befintliga elnätet är en stor del av Sveriges infrastruktur och kräver underhåll och reparation, samtidigt som det behöver anpassas till nya tekniska lösningar för att ställa om till helt förnybar energi. Det finns därmed ett investeringsbehov i branschen samtidigt som företagen står inför stram intäktsreglering. Detta skapar en osäkerhet eftersom företagen inte alltid kan erhålla skäliga intäkter för de långsiktiga investeringar de genomför. Elnätsföretagens investeringar tenderar dock att påverkas av både finansiella och icke-finansiella faktorer, något som tidigare studier visat kan påverka både initiering av investeringar och valet av kalkylmetod. Syfte: Syftet med denna studie ämnar till att förstå och förklara de faktorer som påverkar och initierar investeringar i elnätet hos elnätsföretag. Utifrån de påverkande faktorerna kommer kartläggning göras av vilka kalkylmetoder som används vid utvärdering av investeringsalternativ. På så sätt kan studien kartlägga huruvida det finns ett samband mellan de påverkande faktorerna och valet av kalkylmetod. Metod: Uppsatsen har sin utgångspunkt i en flermetodsforskning där både en kvantitativ och kvalitativ forskningsstrategi har använts med en flerfallsstudie som forskningsdesign. Det empiriska materialet har samlats in med hjälp av enkäter och strukturerade intervjuer. Slutsats: De slutsatser som kan erhållas utifrån studiens syfte är framförallt att politiska och legala faktorer har störst påverkan på initiering av investeringar i elnätsföretag genom framförallt intäktsreglering. Samtidigt har också en illustration kring relationen mellan olika faktorer som ekonomiska, sociala, teknologiska och miljömässiga konstaterats, eftersom de många gånger tenderar att påverka varandra. Ett vagt samband kan också betraktas mellan faktorernas påverkan på företagens val av kalkylmetoder. Vår bedömning är därför, att utifrån den omgivning företagen verkar i med osäkerhet och risk i beaktning, att företagen kritiskt bör granska valet av kalkylmetod och varför den skapar värde för företaget.
66

Combining Smart Energy Storage with a Nordic PV Park : An explorative study of revenue-improving and cost-reducing battery services

Bränström, Amanda, Söderberg, Jonna January 2021 (has links)
With global climate change as the main driver, there is an increase towards including more variable renewable energy (VRE) sources in the electricity mix. Energy production from utilizing the photovoltaic effect, or PV power, is increasing rapidly and is visioned to cover 5 – 10 % of Sweden’s electricity demand in 2040. In addition to rooftop PV production, large- scale PV production in the form of ground-mounted PV parks is gaining ground. A higher share of VRE in the power system creates new challenges as to uphold the power system stability. For a PV park owner, achieving a preferable economic outcome is also a challenge, as the variable electricity output may not match electricity demand. Therefore, combining a PV park with an energy storage, which can store the PV production energy, is seen as a favorable solution. This way, the variability of the electricity production can be reduced and the stored energy in the battery can be used for services benefitting both the PV park owner and the power grid. This study aims to explore the economic potential of combining a PV park with an energy storage. This is achieved by simulating a lithium-ion (Li-ion) battery storage combined with PV production modeled after a 3.5 MW PV park located in Fyrislund, Uppsala. Five cases with individually differing approaches are simulated, exploring how so-called service stacking can be applied with a battery. The investigated services included in the cases are 1) lowering the cost of connecting the PV park to the power grid, 2) lowering the cost of feeding in energy to the power grid, 3) increasing the revenue of selling electricity on the Nord Pool spot market, 4) increasing the revenue by performing energy arbitrage, 5) increasing the revenue by participating in the primary frequency regulating markets to help stabilize the 50 Hz grid frequency. The cases are evaluated by calculating the net present value (NPV) of the system over 10 years with an annual discount rate of 5 %. Battery capacities ranging from 0.1 MWh/0.1 MW to 8 MWh/2 MW are tested. The system configuration achieving the highest NPV occurs when all services are performed, and a 0.13 MWh/0.1 MW battery is used. This NPV is also higher than the NPV when not including a battery in the system. Conclusions include that the spot price impacts the choice of battery capacity to a high extent and that the battery investment cost motivates using a smaller-sized battery.
67

Using Expired Air Carbon Monoxide to Determine Smoking Status During Pregnancy: Preliminary Identification of an Appropriately Sensitive and Specific Cut-Point

Bailey, Beth A. 01 October 2013 (has links)
Background: Measurement of carbon monoxide in expired air samples (ECO) is a non-invasive, cost-effective biochemical marker for smoking. Cut points of 6. ppm-10. ppm have been established, though appropriate cut-points for pregnant woman have been debated due to metabolic changes. This study assessed whether an ECO cut-point identifying at least 90% of pregnant smokers, and misidentifying fewer than 10% of non-smokers, could be established. Methods: Pregnant women (N=167) completed a validated self-report smoking assessment, a urine drug screen for cotinine (UDS), and provided an expired air sample twice during pregnancy. Results: Half of women reported non-smoking status early (51%) and late (53%) in pregnancy, confirmed by UDS. Using a traditional 8. ppm. +. cut-point for the early pregnancy reading, only 1% of non-smokers were incorrectly identified as smokers, but only 56% of all smokers, and 67% who smoked 5. + cigarettes in the previous 24. h, were identified. However, at 4. ppm. +, only 8% of non-smokers were misclassified as smokers, and 90% of all smokers and 96% who smoked 5. + cigarettes in the previous 24. h were identified. False positives were explained by heavy second hand smoke exposure and marijuana use. Results were similar for late pregnancy ECO, with ROC analysis revealing an area under the curve of 95 for early pregnancy, and 94 for late pregnancy readings. Conclusions: A lower 4. ppm ECO cut-point may be necessary to identify pregnant smokers using expired air samples, and this cut-point appears valid throughout pregnancy. Work is ongoing to validate findings in larger samples, but it appears if an appropriate cut-point is used, ECO is a valid method for determining smoking status in pregnancy.
68

Using Expired Air Carbon Monoxide to Determine Smoking Status During Pregnancy: Preliminary Identification of an Appropriately Sensitive and Specific Cut-Point

Bailey, Beth A. 01 October 2013 (has links)
Background: Measurement of carbon monoxide in expired air samples (ECO) is a non-invasive, cost-effective biochemical marker for smoking. Cut points of 6. ppm-10. ppm have been established, though appropriate cut-points for pregnant woman have been debated due to metabolic changes. This study assessed whether an ECO cut-point identifying at least 90% of pregnant smokers, and misidentifying fewer than 10% of non-smokers, could be established. Methods: Pregnant women (N=167) completed a validated self-report smoking assessment, a urine drug screen for cotinine (UDS), and provided an expired air sample twice during pregnancy. Results: Half of women reported non-smoking status early (51%) and late (53%) in pregnancy, confirmed by UDS. Using a traditional 8. ppm. +. cut-point for the early pregnancy reading, only 1% of non-smokers were incorrectly identified as smokers, but only 56% of all smokers, and 67% who smoked 5. + cigarettes in the previous 24. h, were identified. However, at 4. ppm. +, only 8% of non-smokers were misclassified as smokers, and 90% of all smokers and 96% who smoked 5. + cigarettes in the previous 24. h were identified. False positives were explained by heavy second hand smoke exposure and marijuana use. Results were similar for late pregnancy ECO, with ROC analysis revealing an area under the curve of 95 for early pregnancy, and 94 for late pregnancy readings. Conclusions: A lower 4. ppm ECO cut-point may be necessary to identify pregnant smokers using expired air samples, and this cut-point appears valid throughout pregnancy. Work is ongoing to validate findings in larger samples, but it appears if an appropriate cut-point is used, ECO is a valid method for determining smoking status in pregnancy.
69

Hodnocení ekonomické efektivnosti projektů dopravní infrastruktury / Economic Efficiency Evaluation of Transport Infrastructure Projects

Vojdášová, Ivona Unknown Date (has links)
The diploma thesis is focused on evaluation of the economic efficiency of investment projects of transport infrastructure in the Czech Republic. These projekcts are evaluated according to the methodological documents of the Ministry of Transport of the Czech Republic, the State Fund for Transport Infrastructure and thr Directorate of Roads and Motorways of the Czech Republic. The diploma thesis also deals with the comparison od individual methodological procedures and their influence on the resulting indicators of economic efficiency of transport infrastructure condtructions.
70

Dimensioning and Life Cycle Costing of Battery Storage System in residential housing- A case study of Local System Operator Concept

Mehdijev, Shamil January 2017 (has links)
growing concern on achieving environmental sustainability and at the same time making economical savings has become a necessity in our society. The prices of different battery energy storage technologies together with PV cells are declining all around the globe which has led to the fact that there is an increased interest in investing and using these technologies to be able to reach environmental sustainability. The combined system however, must be accurately calculated both when it comes to the sizing and the different costs related to the combined system to be able to make an economical saving. This thesis addresses both of those aspects in Sweden where a residential building with roof-top installed PV system is assessed with a battery energy storage system. An investigation is necessary to be able to assess the different battery storage technologies available in the market today with their specific technical and economical specifications. The electricity market in Sweden, the role of the Distribution System Operator on the electricity pricing with different time tariffs and fuse size subscription, PV generation and battery specifications are investigated and modeled in this study. Sizing of the different battery technologies for the given system is accomplished through a methodology that is developed in this project for the Swedish system. The calculated size of the battery is then used in the Life Cycle Cost analysis, using Monte Carlo simulations for a chosen period of 25 years.Calculations shows that the most appropriate size for the battery system with the given parameters is 6 kWh for all the battery types investigated in this study. The size of the batteries is also shown to be mainly dependent on the charging/discharging time together with the set fuse size margin. Profitability of the Battery Energy Storage system is proven to be mainly dependent on the fuse size downgrade. Sulphur-Sodium battery result in the greatest savings while Vanadium Redox batteries in the least when sizing the batteries. Lithium-Ion battery technology however is most likely to result in the lowest Levelized Cost of Electricity, total- and cycle costs while the highest Net Present Value with 90 % probability in the Monte Carlo simulations. Lithium-Ion battery technology is also found to have the highest probability of having a positive NPV compared to the lowest probability for Sulphur-Sodium battery technology. Lead-Acid battery technology is however shown to have the least uncertainties compared to other Battery Energy Storage technologies due to its maturity. It is additionally shown that government subsidy plays a crucial role when investing in the battery storage system. However, even with the case of removed government subsidy, Lithium-Ion battery technology still results in the largest probability of having a positive NPV while Sulphur-Sodium battery technology results in the lowest probability of having a positive NPV. / Den växande oron för att uppnå miljömässig hållbarhet och samtidigt göra ekonomiska besparingar har blivit en nödvändighet i vårt samhälle. Priserna på olika energilagrings teknologier så som batterier tillsammans med PV-celler minskar runt om i världen vilket har lett till att det finns ett ökat intresse när det gäller att investera och använda dessa teknologier för att kunna nå miljömässig hållbarhet. Det kombinerade systemet måste dock noggrant beräknas både när det gäller storleken och de olika kostnaderna för det kombinerade systemet för att kunna göra en ekonomisk besparing. Denna avhandling behandlar båda dessa aspekter i Sverige där en bostadsbyggnad med takmonterat PV system utvärderas med ett batteri system. En undersökning är nödvändig för att kunna bedöma de olika batteri teknologier som finns tillgängliga på marknaden idag med sina specifika tekniska och ekonomiska specifikationer. Elmarknaden i Sverige, Distribution System Operatörs roll för elprissättning med olika tidstariffer och säkringsabonnemang, PV-generation och batterispecifikationer undersöks och modelleras i denna studie. Dimensionering av olika batteri teknologier för det givna systemet uppnås genom en metod som utvecklats i detta projekt för det svenska systemet. Den beräknade storleken på batteriet används sedan i livscykelkostnadsanalysen, med Monte Carlo-simuleringar under en vald period på 25 år. Beräkningar visar att den optimala storleken för batterisystemet med de angivna parametrarna är 6 kWh för alla batterityper som undersöktes i denna studie. Batteriets storlek visar sig också vara huvudsakligen beroende av laddning / urladdningstiden tillsammans med den inställda säkrings storleken. Lönsamheten hos batterilagringssystemet visar sig vara huvudsakligen beroende av säkringens nedgradering. Svavel-Natriumbatteriet resulterar i de största besparingarna medan Vanadium Redox batteriet i de minsta när dimensionering av batteriet äger rum. Litium-Ion batteriet är emellertid sannolikt att leda till den lägsta nivån av elkostnader, total- och cykelkostnader, medan det högsta nettoförsäljningsvärdet med 90% sannolikhet i Monte Carlo-simuleringarna. Litium-Ion batteriet befanns också ha den högsta sannolikheten att ha en positiv NPV jämfört med Svavel-Natriumbatteriet som resulterar i den lägsta sannolikheten. Lead-Acid batteriet visar sig ha den minsta osäkerheten i jämförelse med andra batterilagrings teknologier på grund av dess mognad. Det framgår dessutom att statlig subvention spelar en avgörande roll när man investerar i ett batteri lagrings system. Dock även med borttagna statliga subventioner, resulterar Litium-Ion batteriet fortfarande största sannolikheten för att ha en positiv NPV, medan Svavel-Natriumbatteriet resulterar den lägsta sannolikheten för att ha en positiv NPV.

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