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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.
81

What are the outcomes and who benefits from the restructuring of the Australian electricity sector?

Chester, Lynne, Social Sciences & International Studies, Faculty of Arts & Social Sciences, UNSW January 2007 (has links)
The last decade has delivered rapid structural change to the Australian electricity sector. The common conceptualisation of the sector's restructuring has been narrowly based around sector-specific regulatory change and the creation of a national electricity market. This thesis argues that such a focus provides an incomplete and inaccurate explanation of the transformation. Three closely interrelated layers of policies and actions embodying the precepts of neoliberalism, and implemented by the state, have driven the sector's transformation. These policies and actions transcend 'electricity-centric' policies and encompass policies which have become systemic to the Australian public sector as well as a third layer which has transformed the prevailing industrial paradigm across all industry sectors. The drivers of the electricity sector's restructuring -- and the outcomes and beneficiaries arising -- form the core research focus of this thesis. The research task is addressed by using the analytical framework of the French theory of r??gulation. The analysis reveals that the electricity sector has been Australia's second largest contributor of privatisation proceeds, remains dominated by government ownership and has falling levels of foreign ownership. Higher relative wage levels and union membership are also evident as have been job losses and substantial real price increases for households whereas those for business have generally fallen. The purported 'reform' centrepiece, the national electricity market, was found to be increasingly uncompetitive due to its own regulatory regime and market manipulation by government-owned companies. In addition, the sector exhibits a heightened precariousness: an unprecedented financial vulnerability arising from a strong appetite for debt and derivatives and exacerbated by payments to government owners not by new investment in generation capacity; increasing tensions between the nation-state and local-state concerning the national electricity market and compromises with labour; and an exposure to political and financial risks from the sector's global integration. The clear winners from the sector's restructuring are the owners of capital and the state, particularly the local-state, although the sustainability of this situation is questionable. The analysis also generates a number of propositions about the application of r??gulation theory to sector-based research.
82

Electrodeposition of platinum-based catalysts for polymer electrolyte membrane fuel cells

Thompson, Scott Damon, 1976- January 2003 (has links)
Abstract not available
83

Sustainability of electricity generation using Australian fossil fuels

May, John R. (John Robert), 1978- January 2003 (has links)
Abstract not available
84

Småskalig elproduktion i Arvika

Pettersson, Niklas, Eriksson, Nils January 2006 (has links)
<p>Arvika Fjärrvärme AB, a district heating company from Arvika, today cover 74 % of their total energy production with biofuel wich runs a 16 MW bioler giving process water at saturated liquid state.</p><p>In recent years Vaporel AB has introduced a new tecnique that gives an external generation of steam after boilers. The concept is built on an adiabatic pressure drop of the saturated liquid in a so called Flashbox which makes a small part of the liquid to evaporate. The generated steam is lead into a turbine where electricity is in a conventional manner.</p><p>The purpose with this rapport was to do a basic study for the specific system at Arvika where it’s possible to see the potential production of electricity that follows an installation of a flasbox.</p><p>The final goal was to introduce an economic analysis of a flashox installation at given conditions.</p><p>To reach our goals we have created a model in Excel where we used the given conditions at Arvika Fjärrvärme to do our calculations. The model has been tested at three different states, of process water returning to potboiler, to be able to decide the optimal operation for the system at present.</p><p>The studies have resulted in a pressure of the processwater at 14,5 bar (at) and a pressuredrop to 9,5 bar (at) in the flashbox. The condenser pressure is set to 0,5 bar (at) what is equal to 81 ˚C. Energy to the district heating net is produced in the condenser and heat exchanger.</p><p>The result of our calculations clearly shows that to reach the highest turbine-efficiency as possible and gain the largest profit the highest process-waterflow possible should be used.</p><p>That means 70 kg/s after present conditions.</p><p>At the highest boiler efficiency the turbine will produce 694 kW. At this state the water that returns to the boiler will be at temperature 148 ˚C (14, 5 bar).</p><p>Totally during a year the production of electric energy could reach 2, 47 GWh/year. The energy used by the pumps will increase with 0,21 GWh over the year at that state.</p><p>Included all economic factors this will generate a profit of 0, 97 million (SEK)/year.</p><p>To make an installation of a flashbox system more profitable an increased generation of electricity have to be made. This could be done by an installation of new pumps to be able to run the process-water at a larger flow to increase the amount of steam made in the flashbox.</p> / <p>Arvika fjärrvärme producerar idag 74% av sitt värmeunderlag via en hetvattenpanna som drivs med biobränsle och har en maxeffekt på 16 MW.</p><p>På senare år har företaget Vaporel AB introducerat en ny teknik på marknaden som ger en extern ångproduktion efter hetvattenpannor.</p><p>Konceptet är byggt på en trycksänkning som medför att delar av det mättade vattnet förångas efter att ha letts in i en så kallad flashbox. Efter flashboxen äntrar ångan en turbin där el produceras på konventionellt vis.</p><p>Syftet med denna rapport har varit att ta fram en grundläggande studie för Arvikas specifika system där det är möjligt att se den potentiella elproduktionen vid en flashboxinstallation.</p><p>Det slutgiltiga målet med rapporten har varit att kunna presentera en lönsamhetsbedömning för en flashboxinstallation vid givna driftfall.</p><p>För att kunna uppfylla uppsatta mål har en Excelmodell konstruerats där beräkningar utförts efter givna förutsättningar, detta utefter tre olika driftfall för att kunna fastställa den mest optimala driften för systemet i dagsläget.</p><p>Studierna har lett fram till att vi har kunnat fastställa ett maximalt tryck efter pannan på 14,5 bar (at) samt en trycksänkning över flashboxen till 9,5 bar. Kondensortryck efter turbinen har satts till 0,5 bar(a) vilket ger en kondensations temperatur motsvarande 81 ˚C. Energi till att värma fjärrvärmevattnet tas via kondensorn samt en värmeväxlare.</p><p>Resultatet av våra beräkningar visar tydligt att vi för att nå en så hög turbineffekt som möjligt och därmed en större lönsamhet skall ha ett så högt processvattenflöde som tillåts, enligt dagens förutsättningar 70 l/s.</p><p>Vid högsta panneffekten kommer turbinen att ge 694 kW, enligt Excelmodellen, vid en returtemperatur till pannan satt till 148 ˚C.</p><p>Sammanlagt under året, med Arvikas varaktighetsdiagram som grund, kommer vi att kunna producera 2,47 GWh el/år varav pumparna kommer att kräva 0,21 GWh el extra per år.</p><p>Med alla ekonomiska faktorer inräknade så kommer detta att ge en vinstkalkyl på 0,97 miljoner /år.</p><p>För att kunna göra dessa installationer lönsamma krävs att vi ökar elproduktionen och därmed den årliga vinsten, detta skulle kunna göras i och med installation av nya pumpar för att uppnå ett större flöde i pannkretsen.</p><p>Vidare bör en studie göras för att bedöma lönsamheten gällande en ombyggnad av rökgaskondenseringen för att kunna klara en större effekt och därmed kunna använda högre returtemperaturer till biopannan. Detta skulle generera ett högre genomsnittligt flöde över året.</p>
85

Power quality study in Macau and virtual power analyzer

Tai, Sio Un January 2012 (has links)
University of Macau / Faculty of Science and Technology / Department of Electrical and Computer Engineering
86

Småskalig elproduktion i Arvika

Pettersson, Niklas, Eriksson, Nils January 2006 (has links)
Arvika Fjärrvärme AB, a district heating company from Arvika, today cover 74 % of their total energy production with biofuel wich runs a 16 MW bioler giving process water at saturated liquid state. In recent years Vaporel AB has introduced a new tecnique that gives an external generation of steam after boilers. The concept is built on an adiabatic pressure drop of the saturated liquid in a so called Flashbox which makes a small part of the liquid to evaporate. The generated steam is lead into a turbine where electricity is in a conventional manner. The purpose with this rapport was to do a basic study for the specific system at Arvika where it’s possible to see the potential production of electricity that follows an installation of a flasbox. The final goal was to introduce an economic analysis of a flashox installation at given conditions. To reach our goals we have created a model in Excel where we used the given conditions at Arvika Fjärrvärme to do our calculations. The model has been tested at three different states, of process water returning to potboiler, to be able to decide the optimal operation for the system at present. The studies have resulted in a pressure of the processwater at 14,5 bar (at) and a pressuredrop to 9,5 bar (at) in the flashbox. The condenser pressure is set to 0,5 bar (at) what is equal to 81 ˚C. Energy to the district heating net is produced in the condenser and heat exchanger. The result of our calculations clearly shows that to reach the highest turbine-efficiency as possible and gain the largest profit the highest process-waterflow possible should be used. That means 70 kg/s after present conditions. At the highest boiler efficiency the turbine will produce 694 kW. At this state the water that returns to the boiler will be at temperature 148 ˚C (14, 5 bar). Totally during a year the production of electric energy could reach 2, 47 GWh/year. The energy used by the pumps will increase with 0,21 GWh over the year at that state. Included all economic factors this will generate a profit of 0, 97 million (SEK)/year. To make an installation of a flashbox system more profitable an increased generation of electricity have to be made. This could be done by an installation of new pumps to be able to run the process-water at a larger flow to increase the amount of steam made in the flashbox. / Arvika fjärrvärme producerar idag 74% av sitt värmeunderlag via en hetvattenpanna som drivs med biobränsle och har en maxeffekt på 16 MW. På senare år har företaget Vaporel AB introducerat en ny teknik på marknaden som ger en extern ångproduktion efter hetvattenpannor. Konceptet är byggt på en trycksänkning som medför att delar av det mättade vattnet förångas efter att ha letts in i en så kallad flashbox. Efter flashboxen äntrar ångan en turbin där el produceras på konventionellt vis. Syftet med denna rapport har varit att ta fram en grundläggande studie för Arvikas specifika system där det är möjligt att se den potentiella elproduktionen vid en flashboxinstallation. Det slutgiltiga målet med rapporten har varit att kunna presentera en lönsamhetsbedömning för en flashboxinstallation vid givna driftfall. För att kunna uppfylla uppsatta mål har en Excelmodell konstruerats där beräkningar utförts efter givna förutsättningar, detta utefter tre olika driftfall för att kunna fastställa den mest optimala driften för systemet i dagsläget. Studierna har lett fram till att vi har kunnat fastställa ett maximalt tryck efter pannan på 14,5 bar (at) samt en trycksänkning över flashboxen till 9,5 bar. Kondensortryck efter turbinen har satts till 0,5 bar(a) vilket ger en kondensations temperatur motsvarande 81 ˚C. Energi till att värma fjärrvärmevattnet tas via kondensorn samt en värmeväxlare. Resultatet av våra beräkningar visar tydligt att vi för att nå en så hög turbineffekt som möjligt och därmed en större lönsamhet skall ha ett så högt processvattenflöde som tillåts, enligt dagens förutsättningar 70 l/s. Vid högsta panneffekten kommer turbinen att ge 694 kW, enligt Excelmodellen, vid en returtemperatur till pannan satt till 148 ˚C. Sammanlagt under året, med Arvikas varaktighetsdiagram som grund, kommer vi att kunna producera 2,47 GWh el/år varav pumparna kommer att kräva 0,21 GWh el extra per år. Med alla ekonomiska faktorer inräknade så kommer detta att ge en vinstkalkyl på 0,97 miljoner /år. För att kunna göra dessa installationer lönsamma krävs att vi ökar elproduktionen och därmed den årliga vinsten, detta skulle kunna göras i och med installation av nya pumpar för att uppnå ett större flöde i pannkretsen. Vidare bör en studie göras för att bedöma lönsamheten gällande en ombyggnad av rökgaskondenseringen för att kunna klara en större effekt och därmed kunna använda högre returtemperaturer till biopannan. Detta skulle generera ett högre genomsnittligt flöde över året.
87

Challenges in low-temperature fuel cells

Gallagher, Kevin Gregory 14 August 2009 (has links)
Low-temperature fuel cells (LTFC) such as phosphoric acid fuel cells (PAFC) and proton exchange membrane fuel cells (PEMFC) are a promising electrochemical energy system for the conversion of hydrogen to electricity. Many challenges must be overcome before commercialization is possible. This dissertation focuses on the degradation of carbon catalyst supports and PEMFC water management. Kinetic studies are presented on the structure-reactivity relationship including an in-depth study of commercially available and model carbons. A mechanism and numerical model of the electrochemical oxidation of graphene-based carbon is proposed to explain longstanding questions. Three mechanisms are concluded to contribute to the current decay commonly observed during electrochemical oxidation: mass loss, reversible passive oxide formation, and irreversible oxide formation. Water uptake and electro-osmosis are investigated to improve the understanding and aid modeling of water transport in PEMFCs below 0 °C. The implication of an electro-osmotic drag coefficient less than unity is discussed in terms of proton transport mechanisms. Capillary pressure saturation relations are presented for carbon fiber paper which can both be used as gas-diffusion layers in PEMFCs. Boundary and scanning curves for imbibition and drainage are measured to further understanding of the hysteresis observed during PEMFC operation.
88

Energetische, exergetische und ökonomische Evaluierung der thermochemischen Vergasung zur Stromerzeugung aus Biomasse /

Wiese, Lars. January 1900 (has links)
Originally presented as the author's Thesis--Technische Universität Hamburg, 2007. / Includes bibliographical references.
89

Solution-based chemical synthesis of electrode materials for electrochemical power sources /

Jeong, Yeon Uk, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 178-184). Available also in a digital version from Dissertation Abstracts.
90

The adaptation-mitigation dilemma is nuclear power a practical solution for climate change? /

Kopytko, Natalie. January 1900 (has links) (PDF)
Thesis (M.E.S.)--Evergreen State College, 2009. / "June, 2009." Title from title screen (viewed 3/16/2010). Includes bibliographical references (p. 150-171).

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