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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.
1

Estimating emissions impacts to the bulk power system of increased electric vehicle and renewable energy usage

Meehan, Colin Markey 24 March 2014 (has links)
The research presented in this thesis examines the use of electric vehicles and renewable energy to reduce emissions of CO₂, SO₂ and NO[subscript x], and within the state of Texas. The analysis examines the impact of increased renewable energy output and electric vehicle charging on the emissions of fossil fuel electric generators used to serve the bulk power system within Texas. The analysis then compares those impacts to alternative scenarios in which fossil fuel generation replaces some renewable energy generation, and Internal Combustion Engine (ICE) vehicles of varying efficiency are used instead of electric vehicles. This research uses temporally-resolved regression analysis combined with a unit commitment and dispatch model that incorporates several different scenarios for EV charging and fuel mixes to evaluate emissions outcomes based on a variety of conditions. Hourly historical generation and emission data for each fossil fuel generator, combined with hourly output data for non-fossil fuel units aggregated by fuel type (i.e. nuclear, wind, hydro-electric) within the Electric Reliability Council of Texas (ERCOT) footprint is regressed to assess the impact of wind generation output on fossil-fuel generation emissions. The regression analysis is used to assess potential increases in emissions resulting from the ramping of fossil-fuel Electric Generation Units (EGUs) to compensate for variability in wind generation output due to changing weather conditions. The unit commitment dispatch model is used to evaluate the impact of changes in customer demand due to increased usage and charging of electric vehicles on the ERCOT system and any resulting increase in emissions from generation used to meet this new demand. The model uses detailed cost, performance and emissions data for EGUs in the ERCOT footprint to simulate the impact of a variety of charging scenarios and fuel mixes on EGU dispatch patterns and any resulting change in system-wide emissions. The results of this model are combined with the results of the regression analysis to present a more complete analysis of the combined impacts of increase EV and renewable energy usage on the emissions of CO₂, SO₂ and NO[subscript x] within the ERCOT footprint. Based on these analyses the increases in renewable energy generation demonstrate clear benefits in terms of emission reductions when the impacts of increased emissions due to more frequent ramping of fossil-fuel units are taken into account. This analysis also finds that EV charging generally has emissions benefits across a range of charging patterns and bulk power system fuel mixes, although in certain circumstances EV charging might result in higher emissions than the use of ICE vehicles. This research finds when future ICE vehicles with reduced emissions are taken into account, approximately half of the modeled scenarios show net emissions benefits from EV charging, while half show net emissions costs when emissions impacts across pollutants are taken into account. / text
2

Simulating the Swedish Electric Energy Production : An optimization perspective

Swahn Azavedo, Michael January 2014 (has links)
Production of electric energy is continuously affected by many factors. Therefore, tools for predicting the future production are needed. In turn, the production affects the electric energy price, which is set on electric energy exchanges. This thesis is intended to find out if the software SDDP can be used for hydrothermal power production simulations in the Nord pool area. By building a simplified model of the electric energy production in Sweden with a focus on hydro, thermal and wind power, the intention is to see how the model is affected by different conditions. The investigated conditions are several; higher and lower water inflows to the hydro power reservoirs; different amounts of installed wind power production; different price levels of emission allowances for CO2. By using the simulation software SDDP, more wind power was seen to lower the electric energy prices, as well as reduce the need of transmission of power from the northern to the southern parts of Sweden. In the simulation, Sweden was divided into four areas, connected where the main bottlenecks in the power grid are located. Water inflows to the reservoirs are crucial in the model. Actual inflow data can be bought from SMHI. However, due to the limited thesis budget, estimations were constructed instead. The estimations were difficult to make and turned out to be too high. Consequently, no reliable evaluation of the SDDP software could be done using this data.
3

[pt] EQUILÍBRIOS DE NASH EM MERCADOS ELÉTRICOS COM FUNÇÕES DE OFERTA QUADRÁTICAS COTADAS / [en] NASH EQUILIBRIA IN POOL-BASED ELECTRICITY MARKETS WITH BOUNDED QUADRATIC SUPPLY FUNCTIONS

MARCELO MORAES RESENDE 20 June 2023 (has links)
[pt] Este trabalho analisa um mercado de eletricidade em que os geradores declaram funções de custo quadráticas para o operador da rede e também suas disponibilidades máximas de produção. O operador, então, determina as quantidades a serem produzidas por cada gerador de modo a atender a uma demanda inelástica, ao menor custo possível. Estabelecem-se alguns resultados que permitem computar os equilíbrios de Nash deste modelo e descrevem-se algumas de suas propriedades, tais como condições de existência. / [en] This work analyzes an electricity market in which generators declare quadratic cost functions for the grid operator and also the maximum capacity available. The operator then determines the quantities that each generator must produce to meet an inelastic demand at the lowest possible cost. Some results are established that allow computing the Nash equilibria of this model and some of their properties are described, such as existence conditions.
4

Cannibalization of Renewable Energy in Spain: Market Implications and Mitigation Strategies through CArbon Pricing and Gurarantess of Origin

Lannhard, Fredrik January 2023 (has links)
Renewable cannibalization refers to the phenomenon where the increasing penetration of zeromarginal cost renewable energy sources, such as solar and wind power, leads to a decline in their market value. By extension, this threatens to reduce investment incentives in wind and solar. Based on theory of supply and demand, the extent to which cannibalization is experienced should increase as the penetration of wind and solar increases. Since electricity prices, and therefore cannibalization, are set with considerations to domestic system dynamics, regulations and policies, cannibalization research are typically limited to investigate it for a specific country or region. For this thesis, Spain has been chosen for the case study. Coupling an already high penetration of both wind and solar with ambitious goals for wind and solar capacity expansion, Spain constitutes an interesting case study for cannibalization research. The investigation is centered around two factors, the market capturing price (MCP) and the cannibalization factor (CF). The MCP is the generation weighted electricity price and measures absolute cannibalization, while the CF is the ratio between the MCP and the average electricity price, thus constituting a relative cannibalization measurement. These will be calculated using hourly day-ahead wind and solar forecasts, and day-ahead electricity prices. A time series econometric study is then conducted to quantify the cannibalization effect together with potentially influential factor that, in theory, should be the driving factors behind the cannibalization phenomenon. To investigate dynamic affects across these factors, temporal regressions are conducted. In these regressions, data is isolated in different groups based on their characteristics. Furthermore, carbon pricing and granular guarantees of origin (GOs) are investigated and assessed based on their potential for alleviating the effect of cannibalization.  The study finds that both wind and solar cannibalizes their own market values, and that cannibalization occurs across technologies. The results indicate that there is a negative marginal relation between wind and solar infeed, suggesting the presence of both self-cannibalization and cross-cannibalization effects on their respective MCPs. The same can be said for the CF of solar, for which there is a negative marginal effect with the infeed of wind and solar. These statements hold true across all ranges of wind and solar penetration investigated in the temporal regression analysis. Moreover, the negative relations increase as the penetration range increases, indicating that cannibalization effects are stronger at high renewable penetration. For wind power, this is not entirely the case. Although the regression results yielded a low coefficient of determination (R2), indicating weak explanatory power in the regressions, it is possible to interpret whether the marginal effects are positive or negative. The temporal regression results indicate that there is a positive marginal effect between solar infeed and the CF of wind when the penetration of solar is lower than 10%. Thus, considering the ambitious wind and solar capacity targets of Spain, the economic viability of wind and solar could be threatened. Furthermore, the results from the study indicate that although carbon pricing helps increasing the MCP for both wind and solar by adding an increment to the day-ahead price, it reduces the CF. Furthermore, carbon pricing is a limited tool for alleviating cannibalization, considering that it requires. Thus, once the system is fully decarbonized, carbon pricing is rendered obsolete. On the contrary, the implementation of granular (hourly) GOs provide extra revenue in addition to the revenue from sold electricity. Furthermore, its immediate effect is that it increases the revenue while not impacting the price of electricity. Thus, it helps counteracting both absolute and relative cannibalization effects. / Förnybar kannibalisering hänvisar till fenomenet där en ökande markandspenetration av förnybar energi med noll marginalkostnad, så som vind- och solkraft, leder till en minskning i deras marknadsvärde. Detta hotar i förlängningen att minska incitament för fortsatta investeringar inom vind- och solkraft. Baserat på teorier om utbud och efterfrågan bör graden av kannibalisering öka i takt med att marknadspenetrationen av vind- och solenergi ökar inom ett givet system. Eftersom elpriser, och därmed graden av kannibalisering, beror på nationella dynamiker inom kraftsystemet, föreskrifter och riktlinjer, utförs ofta studier om kannibaliserade effekter inom förnybar energi från fallstudier inom ett land eller en regions system. I denna avhandling har Spanien valt som fallstudie. Med en redan hög grad av förnybart inom elsystemet, samt ambitiösa mål för fortsatt utbyggnad av vind- och solkraft, utgör Spanien en intressant fallstudie för forskning om förnybar kannibalisering.  Undersökningen utgår från två faktorer; det produktionsviktade elpriset (MCP) och kannibaliseringsfaktorn (CF). MCP utgör en absolut faktor och är det produktionsviktade elpriset för en viss teknologi, medan CF utgör ett mått på relativ kannibalisering och beräknas genom att dividera MCP med det genomsnittliga elpriset. Dessa två faktorer beräknas genom att använda timvisa prognoser från dagen-före marknaden för produktion av vind- och solkraft, samt priser från spotmarknaden. Därefter utförs en ekonometrisk studie baserad på tidseriedata för att kvantifiera de kannibaliserande effekterna med avseende på utomstående faktorer som bör kunna ses som drivkrafter bakom kannibaliseringsfenomenet. Dessutom undersöks och bedöms koldioxidprissättning och timvisa ursprungsgarantier baserat på deras förmåga att lindra effekterna av kannibalisering i Spanien. Studien visar att både vind- och solenergi kannibaliserar sina egna marknadsvärden, samt att kannibalisering sker mellan kraftslag. Resultaten indikerar att det finns en negativ marginaleffekt mellan produktion av vind- och solel, vilket tyder på förekomsten av både självkannibaliserande och korskannibaliserande effekter på deras respektive produktionsviktade elpriser (MCP). Samma kan sägas gälla för solkraftens kannibaliseringsfaktor (CF), där det finns en tydlig negativ marginaleffekt gentemot produktion av vind- och solel. Dessa påståenden stämmer över alla intervall av vind- och solpenetration som undersökts i den temporala regressionsanalysen. Dessutom ökar de negativa relationerna desto högre intervall som avses, vilket tyder på att kannibaliseringseffekten är starkare vid hög penetration av förnybar energi. För vindkraft stämmer inte detta helt. Även om regressionsresultaten gav en låg determinationskoefficient (R2), vilket indikerar svag förklarande kraft i regressionerna, är det möjligt att tolka om marginaleffekterna är positiva eller negativa. De temporala regressionsresultaten visar att det finns en positiv marginal- effekt mellan produktionen av solel och CF för vindkraft när solkraft utgör mindre än 10% av den dagliga produktionen. Med tanke på Spaniens ambitiösa mål för vind- och solkapacitet kan den ekonomiska livskraften för vind- och solenergi hotas. Vidare visar resultaten från studien att även om koldioxidprissättning hjälper till att öka MCP för både vind- och solenergi genom att skapa ett tillägg på spotmarknadspriset, minskar det CF. Dessutom är koldioxidprissättning ett begränsat verktyg för att lindra kannibalisering, med tanke på att det kräver. När systemet är fullständigt avkarboniserat blir koldioxidprissättning överflödig. Å andra sidan ger implementeringen av granulära (timvisa) ursprungsgarantier (GOs) extra intäkter utöver intäkterna från såld el. Dessutom ökar det omedelbart intäkterna utan att påverka elpriset. På så sätt hjälper det till att motverka både absoluta och relativa kannibaliseringseffekter.

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