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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

Eine Methode zur Modellierung prinzipieller Lösungen mechatronischer Systeme /

Kallmeyer, Ferdinand. January 1998 (has links)
Zugl.: Paderborn, Univ., Diss., 1998.
62

Sensitivity analysis of the Brookhaven energy system optimization model

Shapiro, Jeremy F., White, David Edwin, Wood, David O. January 1976 (has links)
Supported in part by the U.S. Army Research Office (Durham) under Contract no. DAAG29-76-C-0064
63

Low prices or self-sufficiency : the conflicting goals of national energy policy

Hall, Robert Ernest, Pindyck, Robert S. January 1976 (has links)
No description available.
64

A Clean Electricity Future: Assessing the Role of Wide-Area Power System Operations in Supporting Weather-Driven Renewable Energy in the U.S.

Picciano, Paul D 01 January 2016 (has links)
Over the coming decades, renewable energy sources, namely wind and solar, will need to play a larger role in our nation’s energy mix as we seek to lower greenhouse emissions and respond to renewable energy policies and the EPA’s Clean Power Plan. This thesis assesses the role of wider-area power system operations in the U.S. as a powerful solution in supporting the integration of these weather-driven, variable energy resources that pose substantial challenges to grid reliability. The expansion and integration of organized electricity markets and transmission networks over wider geographic areas can (1) help reduce net-variability in wind and solar power generation while improving reliability; (2) provide an outlet for over-generation while reducing curtailment; (3) improve resource utilization while enabling resource sharing and lowering electricity costs; and (4) enable low-cost pollution reduction by providing a cheap alternative to fossil-fuel generation. Through power industry assessment, case-study analyses, and modeling research using NOAA’s National Energy with Weather System Simulator to compare scenarios of regional expansion versus a nation power system, this paper evaluates the feasibility and role of wide-area expansion and integration in achieving higher levels of variable renewable energy than our current system is capable of supporting.
65

Die relatiewe ekonomie van sekere direkte en indirekte prosesse vir die vervaardiging van sintetiese olieprodukte.

Niemandt, Mathys Johannes 10 February 2014 (has links)
M.Phil. (Energy Studies) / South Africa has no commercially proven indigenous crude oil deposits. The country therefore follows a well formulated longterm energy policy to ensure a continuous and uninterrupted supply of transport fuels. The development of a very successful synfuel industry contributes to the national desire of maintaining a minimum level of self sufficiency in transport fuels. The Government also plays a supportive role in financing synthetic fuel projects from the Central Energy Fund. South Africa has abundant coal resources at a reasonable cost, as well as the offshore gas field near the coast of Mosselbay. The objective of this study is therefore to evaluate and compare the re1athe economics of certain direct and indirect coal liquefaction process routes, as well as the conversion of natural gas to transport fuels. The methanol option as a transport fuel is also addressed. Information for this study was collected mainly from the literature on this subject as well as Government institutions and private companies that are actively involved in the production of synthetic transport fuels. The primary conclusions of this study are: Synthetic fuel projects are capital intensive. The number of commercially proven options for the production of synfuels are limited to the well proven technology of the Sasol process, conventional methanol synthesis technology and to a lessor extent the Mobil methanol-to-gasoline technology. Accurate costs comparisons will therefore only be possible when more of the direct liquefaction options have been commercially demonstrated. Commercial realisat ion of the unproven technologies also involve enormous financial resources and a high risk. The Sasol synfuel option with the lowest thermal efficiency of approximately 42% requires the highest capital investment per ton or barrel of final product. The high severity direct processes (H-coal, Exxon-Donor-Solvent or EDS and the German Technology) as well as the Mobil-MTG capital investment follows, with the low severity and high thermal efficiency SRC-1 and SRC-2 process capital requirements the lowest, except for the very low,capital investment for a methanol synthesis plant...
66

The statist impulse : the case of Petro-Canada

Lawson, Brian J. (Brian John) January 1981 (has links)
The Statist Impulse: The Case of Petro-Canada seeks to find cause for the establishment and phenomenal growth of Canada's National Petroleum Corporation. The study argues that Petro-Canada is part and parcel of an historically constituted statist dynamic common to all advanced capitalist countries. Utilizing Marxist theory, the thesis contends that statism serves to resolve the problems or failures of capitalist economies, and is an essential prerequisite for the growth of capital. Such was the case with Petro-Canada. The international oil crisis of the early seventies, which resulted in so much economic disorder and concern about future energy security, caused governments to increasingly turn to state enterprise, in the hope of filling their national petroleum needs. The statist impulse was furthered by the fact that the private oil companies, particularly in the eyes of .the majority of governments, failed to respond to the crisis adequately or satisfactorily. After an examination of the western industrialized nations growing reliance on state capitalist forms for obtaining energy security, the thesis investigates Petro-Canada in more detail. The study develops the point that Canada's vigorous public enterprise tradition played no small role in the crown corporation's creation and success. It is then argued that although the NDP and nationalist wave of the late 1960's spawned the concept of a Petro-Canada, the Liberals and Federal state singlehandedly implemented the proposal. The Government wholeheartedly embraced Petro-Canada, not for the sake of the NDP, but for reasons having to do with state capitalism. Through Petro-Canada's subsequent participation in numerous joint ventures, the state has socialized part of the private oil industry's exploration and development risk so as to prod the petroleum corporations into greater activity. But the crown corporation has also acted as a substitute for the petroleum giants in certain areas, such as crude importation, so as to protect energy dependent general capital. The study contends that from a position of outright hostility toward Petro-Canada, the private sector gradually accepted state intervention into petroleum because of the lucrative joint ventures. Accordingly, it is argued that the state acted autonomously in setting-up Petro-Canada, without the support of the Canadian bourgeoisie. Finally, the study looks at the Tory effort to dismantle Petro-Canada and concludes that statism, in the form of the National Petroleum Corporation, proved too potent a force for the Conservatives to tackle. The issue of 'privatization' politically isolated the Tories from the majority of Canadians and became such a contentious internal issue that it divided and paralyzed the Conservative Government. In the end, Petro-Canada helped defeat the Tories and symbolizes the victory of state-capitalism over anti-statism. / Arts, Faculty of / Political Science, Department of / Graduate
67

Performance benchmarking: Creating measurable energy and monetary savings in the real estate industry

January 2013 (has links)
0 / SPK / specialcollections@tulane.edu
68

Integration of renewable energy into Nigerian power systems

Awodiji, Olurotimi Olakunle January 2017 (has links)
Many countries are advancing down the road of electricity privatization, deregulation, and competition as a solution to their growing electricity demand and other challenges posed by the monopolistic nature of the existing structure. Presently, Nigeria has a supply deficit of electricity as a result of the growing demand. This imbalance has negatively affected the economy of the country and the social-economic well-being of the population. Hence, there is an urgent need to reform the power sector for greater efficiency and better performance. The objectives of the reform are to meet the growing power demand by increasing the electric power generation and also by increasing competitiveness through the participation of more private sector entities. The renewable energy integration is one way of increasing the electricity generation in the country in order to cater for the growing demand adequately. Examples of the renewable energy that is available in the country include wind, geothermal, solar and hydro. They are considered to be environmentally friendly, replenishable and do not contribute to the climate change phenomena. The country presently generates the bulk of its electricity from both thermal (85%) and hydroelectric (15%) power plants. While electricity generation from the thermal power stations constitutes the largest share of greenhouse emission, this is mostly from burning coal and natural gas. The effect of this high proportion of greenhouse emission causes climate change which is referred to as a variation in the climate system statistical properties over a long period of time. It has been observed that many of the activities of human beings are contributory factors to the release of these greenhouse gases (GHG). But, as the traditional sources of energy continue to threaten the present and future existence on the planet earth, it is, therefore, imperative to increase the integration of the variable renewable energy sources in a sustainable and eco-friendly manner over a long period of time. The variability and the uncertainties of the renewable energy source's output, present a major challenge in the design of an efficient electricity market in a deregulated environment. The system deregulation and the use of renewable sources for the generation of electricity are major changes presently being experienced in power system. In a deregulated power system, the integration of renewable generation and its penetration affects both the physical and the economic operations. The main focus of this research is on the integration of wind energy into Nigerian power systems. Up till now, research on the availability of the wind energy and its economic impacts has been limited in Nigeria. Generally, the previous study of wind energy availability in Nigeria has been limited in scope. The wind energy assessment study has not been detailed enough to be able to ascertain the wind energy potential of the country. To cope with this shortcoming, a detailed statistical wind modeling and forecasting methodology have been used in this thesis to determine the amount of extractable wind energy in six selected locations in Nigeria using historical wind speed data for 30 years. The accuracy test of the statistical models was also carried using the Mean Absolute Error (MAE), Root Mean Square Error (RMSE), and Chi-Square methods to determine the inherent error margin in the modeling and analysis. It is found that the error margin of the evaluations falls within the expected permissible tolerance range. For a more detailed wind assessment study of the Nigeria weather, the seasonal variation of the weather conditions as it affects the wind speed and availability during the two major seasons of dry and rainy was considered. A Self-Adaptive Differential Evolution (SADE) was used to solve the economic load dispatch problem that considers the valve-point effects and the transmission losses subject to many constraints. The results obtained were compared with those obtained using the "standard" Differential Evolution (DE), Genetic Algorithm (GA), and traditional Gradient Descent method. The results of the SADE obtained when compared with the GA, DE, and Gradient descent show the superiority of SADE over all the other methods. The research work shows that the wind energy is available in commercial quantity for generation of electricity in Nigeria. And, if tapped would help reduce the gap between the demand and supply of electricity in the country. It was also demonstrated that the wind energy integration into the power systems affects the generators total production cost.
69

Achieving Equitable Offshore Wind Development: Lessons from European Stakeholders

Hirshfeld, Kacey 01 January 2023 (has links) (PDF)
The Biden Administration has set aggressive offshore wind energy goals, aiming to have 30 gigawatts of offshore energy in place by 2030. This amount of energy has the potential to power 10 million homes (White House, 2022), helping the administration to reach larger clean energy goals. In Virginia, Dominion Energy aims to have 2.6 gigawatts of offshore wind energy by 2026, enough to power up to 660,000 homes (Dominion Energy). While the upcoming offshore wind energy development will create clean energy and green jobs, the ocean is no longer an open field for development and already supports a complex matrix of industries (Schupp et al., 2019). The number of competing uses for space is continually expanding, causing increases in conflicts between sectors (de Groot et al., 2014). From fisheries and offshore aquaculture to shipping channels and military use, the need for sustainably managed offshore development is greater now than ever before (Gill et al., 2020). This research uses European stakeholder knowledge and experiences to highlight opportunities for conflict mitigation in the United States. Europe is about 20 years ahead of the United States in offshore wind development (Gill et al., 2020), and due to the diversity in regulatory statuses across countries (Schupp et al., 2019), a multitude of case studies exist for examining strategies to deal with competing ocean uses.
70

Russian Energy Policy: Exploring the Efficacy of a Resource‐Dependent Economy and Foreign Policy

Hendrix, Leigh E. January 2008 (has links)
No description available.

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