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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.
341

Essays in energy economics and industrial organization

Wang, Xueting January 2021 (has links)
In chapter 1, I study long term contracts in retail electricity markets. Deregulation of retail electricity markets gives consumer choices over contracts of different lengths. Long term contracts allow consumers to hedge against future price increase, but they can be more expensive than spot contracts. There is little empirical evidence on how consumers value long term contracts. Using a dataset from an incumbent retailer containing 10-year panel of consumer contract choice data, this paper analyzes consumers' valuations of long term contracts. I first document that a significant percentage of consumers actively choose long term contracts when they are more expensive than shorter contracts. To quantify the value of long term contracts and welfare implication of product innovation after retail deregulation, I build and estimate a dynamic model that incorporates risk preference, price expectations and consumer inertia. Counterfactual calculation shows that on average consumers gain about 6% per month from long term contracts. In chapter 2, I quantify the effect of introducing large-scale renewable energy on the wholesale electricity market. Renewable energy capacity has increased in many markets as renewable is crucial to reduce emission in the energy sector. More than 8GWh of wind capacity has been added in Texas between 2014 and 2017. Using hourly data from Texas, I find increasing daily wind energy production results in statistically significant reduction of wholesale electricity price for all hours of the day except 10pm, and the effect is larger during peak hours. Increasing wind production reduces output from both coal and natural gas power plants. Using hours when no transmission limit is binding and load is above 50th percentile in the load distribution, I find increasing hourly wind production reduces offer prices submitted by owners of fossil fuel power plants. In chapter 3, I study the effect of transmission limit on market outcomes. Wholesale electricity markets are often subject to transmission constraints that prevent efficient dispatch of power. Increasing renewable capacity demands transmission infrastructure investment. In 2011 to 2013, Electricity Reliability Council of Texas (ERCOT) constructed several high voltage transmission lines from the wind-rich west Texas to demand centers. Using data on electricity production, demand, price and information on grid congestion, this paper shows that an increase of 100MW in the transmission limit from the West to the North reduces the hourly output of fossil fuel generators in the North by 71.1MWh and decreases the price in the North by 0.17$/MWh when the transmission constraint from the West to the North is binding. Meanwhile, the increase of the transmission limit reduces dispatch of coal and combined cycle gas power plants in the North, but increases production of simple cycle and steam gas power plants in the North.
342

Stochastic Modelling of Daily Peak Electricity Demand Using Value Theory

Boano - Danquah, Jerry 21 September 2018 (has links)
MSc (Statistics) / Department of Statistics / Daily peak electricity data from ESKOM, South African power utility company for the period, January 1997 to December 2013 consisting of 6209 observations were used in this dissertation. Since 1994, the increased electricity demand has led to sustainability issues in South Africa. In addition, the electricity demand continues to rise everyday due to a variety of driving factors. Considering this, if the electricity generating capacity in South Africa does not show potential signs of meeting the country’s demands in the subsequent years, this may have a significant impact on the national grid causing it to operate in a risky and vulnerable state, leading to disturbances, such as load shedding as experienced during the past few years. In particular, it is of greater interest to have sufficient information about the extreme value of the stochastic load process in time for proper planning, designing the generation and distribution system, and the storage devices as these would ensure efficiency in the electrical energy in order to maintain discipline in the grid systems. More importantly, electricity is an important commodity used mainly as a source of energy in industrial, residential and commercial sectors. Effective monitoring of electricity demand is of great importance because demand that exceeds maximum power generated will lead to power outage and load shedding. It is in the light of this that the study seeks to assess the frequency of occurrence of extreme peak electricity demand in order to come up with a full electricity demand distribution capable of managing uncertainties in the grid system. In order to achieve stationarity in the daily peak electricity demand (DPED), we apply a penalized regression cubic smoothing spline to ensure the data is non-linearly detrended. The R package “evmix” is used to estimate the thresholds using the bounded corrected kernel density plot. The non-linear detrended datasets were divided into summer, spring, winter and autumn according to the calender dates in the Southern Hemisphere for frequency analysis. The data is declustered using Ferro and Segers automatic declustering method. The cluster maxima is extracted using the R package “evd”. We fit Poisson GPD and stationary point process to the cluster maxima and the intensity function of the point process which measures the frequency of occurrence of the daily peak electricity demand per year is calculated for each dataset. The formal goodness-of-fit test based on Cramer-Von Mises statistics and Anderson-Darling statistics supported the null hypothesis that each dataset follow Poisson GPD (σ, ξ) at 5 percent level of significance. The modelling framework, which is easily extensible to other peak load parameters, is based on the assumption that peak power follows a Poisson process. The parameters of the developed i models were estimated using the Maximum Likelihood. The usual asymptotic properties underlying the Poisson GPD were satisfied by the model. / NRF
343

Die Rolle kommunaler Elektrizitätsversorgungsunternehmen im Zentrum einer kooperativen Aufgabenerledigung zwischen Staat und Privatwirtschaft im Bereich der örtlichen Elektrizitätsversorgung / The Role of Municipal Electric Utilities in Cooperative Execution Agreements between the Government and Private Sector within the Context of Local Electricity Supply

Nönnig, Constanze 24 August 2012 (has links) (PDF)
Gegenstand der Dissertation ist die Verantwortung der Kommunen für die Versorgung der örtlichen Bevölkerung mit Elektrizität: Woraus kann sie hergeleitet werden, welche Konsequenzen ergeben sich aus ihr für die Kommunen und welche Bedeutung kommt hierbei der Kooperation mit der Privatwirtschaft zu? Die in drei Teile gegliederte Arbeit befasst sich in ihrem ersten Teil mit den allgemeinen Grundlagen und der Entwicklung kommunaler Elektrizitätsversorgungsunternehmen. Im zweiten Teil geht es um die gesetzlichen Zielvorgaben in der Elektrizitätswirtschaft und die kommunale Verantwortung für ihr Erreichen. Der dritte Teil schließlich befasst sich mit den Voraussetzungen kooperativer Staatstätigkeit und dem Potenzial der Anwendung von Kooperationsmodellen im Bereich der örtlichen Elektrizitätsversorgung. / The dissertation ist focused on the responsibility of municipalities to supply local populations with electricity: Where can it be derived from, what consequences for municipalities arise from it and what role does the cooperation with private sector have in this context? The thesis is divided into three parts; the first part deals with the basic principles and the development of municipal electric utilities. The second part focuses on both statutory normative targets in the electricity supply industry and the municipality's responsibility to achieve them. Finally, the third part discusses the preconditions of cooperative government activity and the potential of cooperation models for application to local power supply.
344

Electrical energy efficiency awareness by poor communities in South Africa and its impact on their energy needs

Mthiyane, Frederick Sandile 03 1900 (has links)
Thesis (MBA (Business Management))--University of Stellenbosch, 2008. / AFRIKAANSE OPSOMMING: Die Suid-Afrikaanse Heropbouings Program (HOP) asook die Groei Indiensnemings- en Herverdelingsprogram(GEAR) het ‘n geweldige hoë standaard gestel vir die verskaffing van basiese dienste soos behuising en elektrifisëring vir almal. Die meer effektiewe gebruik van elektriese energie het die sosiale en politieke potensiaal om by te dra tot die sukses van GEAR ten opsigte van die geteikende lae inkomste gemeenskappe waar daar nie tans voldoende elektriese energie beskikbaar is nie. Hierdie studie dek ook die inisiatiewe ten opsigte van effektiewe elektriese energie waaroor die Suid-Afrikaanse regering in vennootskap met Eskom tans navorsing doen om te bepaal of daar enige ekonomiese waarde is, en/of die lae inkomste gemeenskappe deur die sogenoemde inisiatiewe bevoordeel kan word. Die studie sluit ook navorsing in om die bewustheid van die lae inkomste gemeenskappe ten opsigte van effektiewe elektriese energie te bepaal. Die studie kyk verder na verskeie ander voltooide studies ten opsigte van effektiewe energie in lae inkomste gemeenskappe. Alhoewel verskeie ander effektiewe energie programme wel hoë ekonomiese en omgewings voordele uit 'n sosiale oogpunt inhou, is dieselfde programme glad nie aantreklik vir die verbruikers nie. Vir hierdie feit is die regering se bemiddeling wel belangrik. Die uitslag van die studie ondersoek ook die verskillende beleidsopsies (nie in diepte nie) om die struikelblokke van effektiewe energie te oorkom, asook moontlike oplossings vir die regering om die verskille tussen wat goed is vir die gemeenskap, en wat goed is vir die elektriese industrie te oorbrug. Die studie toets ook die bewustheid van effektiewe energie onder die lae inkomste gemeenskappe en hul huidige deelname aan effektiewe energie programme. / ENGLISH ABSTRACT: South Africa’s Reconstruction and Development Programme (RDP) as well as Growth Employment and Redistribution (GEAR) set ambitious goals for providing basic services to all, including housing and electrification. More efficient use of electrical energy has the potential to socially and politically support the goals of GEAR, particularly when it is targeted at low-income communities lacking adequate energy services. This study looks at electrical energy efficiency initiatives that the South African government has under taken on its own as well as in partnership with Eskom and to check if there is any economic value that the poor communities may benefit from these initiatives. The study will also check the awareness of poor communities of electrical energy efficiency. Various studies in the subject of energy efficiency in relation to the poor communities that have been done in the past will also be looked at in this study. While many energy efficiency programmes may have significant economic and environmental benefits from a social perspective, they may not be as attractive to utilities and consumers. That is why government intervention is important. As a result this study also examine (not in great depth) the policy options for overcoming the significant barriers to energy efficiency, and ways government can bridge the gap between what is good for society and what is good for the electricity industry. This study extends further on checking the awareness of energy efficiency by the poor communities and their current participation in the energy efficiency programmes.
345

An analysis of the residential user electricity market and the marketing of green electricity product solutions in the City of Cape Town

Kritzinger, Brian 12 1900 (has links)
Thesis (MBA (Business Management)) -- University of Stellenbosch, 2009. / AFRIKAANSE OPSOMMING: Hierdie navorsingstudie het ’n telefoniese vraelys behels wat aan die einde van 2007 deur 405 respondente voltooi is. Die doel van die vraelys was om die opinies van ’n verteenwoordigende steekproef Kaapstadse residensiële elektrisiteitsverbruikers te bepaal ten opsigte van kwessies wat verband hou met die opwekking, verkoop en gebruik van hernubare of groen elektrisiteit. Dit is gedoen ten einde ’n ingeligte formulering te kan doen van toepaslike groen elektrisiteitsprodukte vir verkoop aan die residensiële elektrisiteitsmark. Response is op Likert-skale aangedui en is geanaliseer deur middel van nie-parametriese statistiese metodologie. Daar is bevind dat ’n groot proporsie (90.6 persent) van die Kaapstadse verbruikers bewus is van en besorg is oor die huidige klimaats- en omgewingsuitdagings en dat ’n soortgelyke proporsie (86.9 persent) bekommerd is oor die gevaar van aardse verwarming. Daar is ook bevind dat 85.0 persent van respondente gebruik maak van energiebesparende gloeilampies. Daar kon egter geen beduidende verwantskappe gevind word tussen die algemeen-aanvaarbare groener tegnologieë en die verbruikers se bereidheid om meer te betaal vir groen elektrisiteit nie. Daar is bevind dat 61.7 persent van die respondente bereid sou wees om tot 15.4 persent as ’n premie te betaal ten einde groen elektrisiteit te koop. Daar is verder bevind dat van die drie voorgestelde aankoopmetodes, groen notas (green tags) of groen kwitansies vir voorafbetaalde elektrisiteit die mees praktiese is en waarskynlik die mees algemeen aanvaar sal word. Verbruikers verkies om elke keer wat hulle elektrisiteit koop die keuse te kan uitoefen tussen groen elektrisiteit en konvensionele krag en dan is die voorafbetaalde manier van koop die mees geskikte opsie om die aankoop van groen elektrisiteit te bestuur. ENGLISH ABSTRACT: This study comprised of a telephonic questionnaire conducted in late 2007 with 405 respondents. The aim of the questionnaire was to derive the opinions of a representative sample of Cape Town’s residential electricity consumers on matters relating to the generation, sale and use of renewable or green electricity. This was done in order to inform the formulation of appropriate green electricity products for sale into the residential electricity market. Responses were noted on Likert scales and were analysed using nonparametric statistical methodology. It was found that a high proportion (90.6 per cent) of the Capetonian consumers were concerned about the environment and a similarly highly number (86.9 per cent) are concerned about the environmental challenges that are currently faced as a result of global warming. It was found that 85.0 per cent of households in the respondent population currently make use of energy-saving light bulbs. However no significant links could be found between the use of generally-accepted greener technologies and the consumers’ willingness to pay more for green electricity. It was found that 61.7 per cent of the respondents were willing to spend an average of 15.4 per cent more as a premium in order to buy green electricity. It was further found that of the three purchasing methods suggested that green tags, or green receipts for pre-paid electricity were the most practical and the most likely to be widely accepted. Consumers preferred the option of choosing at every purchase whether they opt for green electricity or conventional power and this would be most easily managed via a pre-paid receipt system.
346

Strategies Utility Managers Used to Implement Renewable Energy Technologies in the Caribbean

Archer, Nneka Cori-anne 01 January 2015 (has links)
Government officials in the Caribbean are encouraging the production of electricity from renewable energy sources to reduce the impact of high electricity rates to customers due to region's dependency on imported fossil fuel. The purpose of this single-case study was to explore the strategies electric utility managers in the Caribbean used to implement renewable energy technologies. The diffusion of innovation theory served as the conceptual framework for the study. Three managers of an electric utility in the Caribbean, who had created strategies to implement renewable energy technologies, participated in face-to-face semistructured interviews. These managers provided in-depth information on approaches used to implement these technologies. Three themes emerged from the thematic analysis of data that were collected from the semistructured interviews and document reviews: development and integration of renewable energy technologies into utility operations, avoidance of future investments in fossil fuels, and inclusion of key stakeholders in the transition to implementing renewable energy technologies. The implications for social change to the Caribbean region from a successful implementation of the technologies may include employment opportunities through the creation of new industries, eradication of energy poverty, and a healthier and cleaner environment. Also, government officials can save significant foreign exchange by not having to import fossil fuel for electricity generation and use these savings to invest in other sectors that can provide further economic and social growth for the people of the region.
347

Integrated Modeling of Electric Power System Operations and Electricity Market Risks with Applications

Sun, Haibin 14 November 2006 (has links)
Through integrated modeling of power system operations and market risks, this thesis addresses a variety of important issues on market signals modeling, generation capacity scheduling, and electricity forward trading. The first part of the thesis addresses a central problem of transmission investment which is to model market signals for transmission adequacy. The proposed system simulation framework, combined with the stochastic price model, provides a powerful tool for capturing the characteristics of market prices dynamics and evaluating transmission investment. We advocate the use of an AC power flow formulations instead since it allocates transmission losses correctly and reveals the economic incentives of voltage requirements. By incorporating reliability constraints in the market dispatch, the resulting market prices yield incentives for market participants to invest in additional transmission capacity. The second part of the thesis presents a co-optimization modeling framework that incorporates market participation and market price uncertainties into the capacity allocation decision-making problem through a stochastic programming formulation. Optimal scenario-dependent generation scheduling strategies are obtained. The third part of the thesis is devoted to analyzing the risk premium present in the electricity day-ahead forward price over the real-time spot price. This study establishes a quantitative model for incorporating transmission congestion into the analysis of electricity day-ahead forward risk premium. Evidences from empirical studies confirm the significant statistical relationship between the day-ahead forward risk premium and the shadow price premiums on transmission flowgates.
348

Design and implementation of a software tool for day-ahead and real-time electricity grid optimal management at the residential level from a customer's perspective

Hubert, Tanguy Fitzgerald 07 July 2010 (has links)
This thesis focuses on the design and implementation of a software tool able to achieve electricity grid optimal management in a dynamic pricing environment, at the residential level, and from a customer's perspective. The main drivers encouraging a development of energy management at the home level are analyzed, and a system architecture modeling power, thermodynamic and economic subsystems is proposed. The user behavior is also considered. A mathematical formulation of the related energy management optimization problem is proposed based on the linear programming theory. Several cases involving controllable and non-controllable domestic loads as well as renewable energy sources are presented and simulation scenarios illustrate the proposed optimization strategy in each case. The performance of the controller and the changes in energy use are analyzed, and ideas for possible future work are discussed.
349

Financial and computational models in electricity markets

Xu, Li 22 May 2014 (has links)
This dissertation is dedicated to study the design and utilization of financial contracts and pricing mechanisms for managing the demand/price risks in electricity markets and the price risks in carbon emission markets from different perspectives. We address the issues pertaining to the efficient computational algorithms for pricing complex financial options which include many structured energy financial contracts and the design of economic mechanisms for managing the risks associated with increasing penetration of renewable energy resources and with trading emission allowance permits in the restructured electric power industry. To address the computational challenges arising from pricing exotic energy derivatives designed for various hedging purposes in electricity markets, we develop a generic computational framework based on a fast transform method, which attains asymptotically optimal computational complexity and exponential convergence. For the purpose of absorbing the variability and uncertainties of renewable energy resources in a smart grid, we propose an incentive-based contract design for thermostatically controlled loads (TCLs) to encourage end users' participation as a source of DR. Finally, we propose a market-based approach to mitigate the emission permit price risks faced by generation companies in a cap-and-trade system. Through a stylized economic model, we illustrate that the trading of properly designed financial options on emission permits reduces permit price volatility and the total emission reduction cost.
350

Environmental impact assessment and organisational change in Transport SA & ETSA Corporation / Megan Emma McCarthy.

McCarthy, Megan Emma January 2000 (has links)
Includes bibliographical references (leaves 379-409) / 2 v. : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Develops a framework for evaluating environmental impact assessment (EIA) and organisational change, and examines the influence of the EIA system on two government organisations within South Australia, Transport SA and ETSA . Finally analyses patterns of organisational change process in South Australia in comparision with experience in the United States. / Thesis (Ph.D.(Arts))--Adelaide University, Dept. of Geographical and Environmental Studies, 2001

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