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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.
101

Energetická politika Európskej únie - jadrová energia v Európe / Energy policy of the EU - Nuclear power in Europe

Kovácsik, Miroslav January 2009 (has links)
The events of the recent past in the energy department in Europe have shown how big is it's dependency on import of the primary energy resources. In the long run it is obvious that a high dependency on import of resources with the increasing demand of the population will not be able to provide Europe with so much needed easy accessible and reasonably priced energy. The integration process in Europe lasts more than fifty years now but energy policy is even after the ratification of the Lisbon treaty in controll of the national parlaments of member countries. Even though the options and posibilitie of the countries differ in the long run a closer cooperation is mandatory. The thesis is about the united energy policy in Europe and the development it went through since the beginning of the integration process in the fifties of last century. I will describe the main events that formed it as well as the main resources of energy production in the EU. I will explain the term energy security and in the end I will write about nuclear power that is today a vary efficient but after the events of Fukushima also controversial alternative of energy independence.
102

Modelo de caracterização sistêmica das opções de oferta energética para o PIR. / Model of global characterization of energy resources options for IRP.

Fujii, Ricardo Junqueira 01 December 2006 (has links)
O Planejamento Energético tradicional geralmente privilegia os custos econômicos dos recursos energéticos, relegando ao segundo plano questões políticas, sociais e ambientais. Este trabalho pretende estimular a mudança desta abordagem através da proposição de um modelo de caracterização de recursos energéticos integrando todas essas quatro dimensões. São dois seus objetivos: o fornecimento de uma metodologia para avaliar o custo global dos recursos energéticos e de outra para estimar o potencial de tais recursos. Para facilitar o processo de avaliação, o modelo sugere o uso da ACC - Avaliação de Custos Completos, a qual permite a análise qualitativa e quantitativa de custos, reduzindo a necessidade de dados quantitativos, limitados em certos casos. Ilustra-se a aplicação do modelo com um exemplo de caracterização dos recursos na região de Araçatuba, localizada no Oeste Paulista. Os resultados revelam que, quando considerados os custos globais, a adoção de recursos renováveis apresenta grande competitividade, ao contrário de outros que, apesar de serem economicamente atraentes, não apresentam custos globais aceitáveis. / The Traditional Energy Planning usually favors technical-economic costs, relegating political, social and environmental issues to a less important level of analyses. This work tries to encourage a change in such approach by elaborating a model of energy resources characterization integrating all four dimensions - environmental, political, social and economic. The model aims at two objectives: providing a method of assessing the global cost of energy resources and estimating its potential considering the limitations provided by these dimensions. The integration of distinct elements constitutes a complex and tricky activity that can result in inaccurate results if not taken carefully. To minimize this complexity, the Model suggests the use of the Full Cost Accounting - FCA - method, which allows the consideration of quantitative and qualitative costs, reducing the demand for quantitative data, limited in some cases. The Model has been applied in the characterization of the region of Araçatuba, located in the western part of the state of São Paulo, the most populated state in Brazil. The results reveal that the adoption of renewable sources is quite attractive, especially when global costs are taken into account. On the other hand, other resources don\'t present acceptable global costs despite being economically attractive.
103

Development and Implementation of Control Strategies for Effective Management of Distributed Energy Resources

Kini, Roshan Laxman January 2019 (has links)
No description available.
104

Overcoming Voltage Issues Associated with Integration of Photovoltaic Resources in the Electric Grid

Rahimi, Kaveh 15 March 2018 (has links)
Power generation from solar energy has significantly increased, and the growth is projected to continue in the foreseeable future. The main challenge of dealing with solar energy is its intermittent nature. The received irradiation energy of the sun on the earth's surface can fluctuate in a matter of seconds and cause voltage issues to power systems. Considering the high growth rate of solar photovoltaic (PV) resources, it is essential to be prepared to encounter and manage their high penetration levels. Currently, simplified approaches are used to model the impacts of cloud shadows on power systems. Using outdated standards also limits the penetration levels more than required. Approximately 40% of the new PV installations are residential, or installed at a low voltage level. Currently, all components between utility distribution transformers and customers/loads are either ignored or modeled with oversimplification. Furthermore, large PV systems require a considerable amount of land. However, point sensor models are currently used to simulate those systems. With a point model, the irradiance values measured at a point sensor are used to represent the output of a large PV system. However, in reality, clouds cover photovoltaic resources gradually and if the solar arrays are widespread over a large geospatial area, it takes some time for clouds to pass over the solar arrays. Finally, before 2014, participation of small-scale renewable resources was not allowed in controlling voltage. However, they can contribute significantly in voltage regulation. The main objective of this dissertation is to address the abovementioned issues in order to increase the penetration levels as well as precisely identify and locate voltage problems. A time-series analysis approach is used in modeling cloud motion. Using the time-series approach, changes of the received irradiation energy of the sun due to cloud shadows are simulated realistically with a Cloud Motion Simulator. Moreover, the use of the time-series approach allows implementation of new grid codes and standards, which is not possible using the old step change methods of simulating cloud impacts. Furthermore, all electrical components between utility transformers and customers are modeled to eliminate the inaccuracy due to using oversimplified models. Distributed PV models are also developed and used to represent large photovoltaic systems. In addition, the effectiveness of more distributed voltage control schemes compared to the traditional voltage control configurations is investigated. Inverters connect renewable energy resources to the power grid and they may use different control strategies to control voltage. Different control strategies are also compared with the current practice to investigate voltage control performance under irradiation variations. This dissertation presents a comprehensive approach to study impacts of solar PV resources. Moreover, simulation results show that by using time-series analysis and new grid codes, as well as employing distributed PV models, penetration of solar PV resources can increase significantly with no unacceptable voltage effects. It is also demonstrated that detailed secondary models are required to accurately identify locations with voltage problems. / PHD
105

Ocean energy assessment : an integrated methodology

Banerjee, S. January 2011 (has links)
The huge natural energy resources available in the world’s oceans are attracting increasing commercial and political interest. In order to evaluate the status and the degree of acceptability of future Ocean Energy (OE) schemes, it was considered important to develop an Integrated Assessment Methodology (IAM) for ascertaining the relative merits of the competing OE devices being proposed. Initial studies included the gathering of information on the present status of development of the ocean energy systems on wave, OTEC and tidal schemes with the challenges faced for their commercial application. In order to develop the IAM, studies were undertaken for the development and standardization of the assessment tools focussing on: • Life Cycle Assessment (LCA) on emission characteristics. • Energy Accounting (EA) studies. • Environmental Impact Assessment (EIA) over different environmental issues. • Resource captures aspects. • Defining economy evaluation indices. The IAM developed from such studies comprised of four interrelated well defined tasks and six assessment tools. The tasks included the identification of the modus operandi on data collection to be followed (from industry) for assessing respective OE devices, and also advancing relevant guidelines as to the safety standards to be followed, for their deployment at suitable sites. The IAM as developed and validated from case studies in ascertaining relative merits of competing OE devices included: suitable site selection aspects with scope for resource utilisation capability, safety factors for survivability, scope for addressing global warming & energy accounting, the environmental impact assessment both qualitatively and quantitatively on different environmental issues, and the economic benefits achievable. Some of the new ideas and concepts which were also discovered during the development of the IAM, and considered useful to both industry and researchers are given below: • Relative Product Cost (RPC) ratio concept- introduced in making an economic evaluation. This is considered helpful in sensitivity analysis and making design improvements (hybridising etc) for the cost reduction of OE devices. This index thus helps in making feasibility studies on R&D efforts, where the capital cost requirement data and life span of the device is not well defined in the primary stages of development. • Determination of the threshold limit value of the barrage constant - considered useful in determining the efficacy of the planning process. The concept ascertained the relative efficiency achieved for various barrage proposals globally. It could also be applied to suggest the revisions required for certain barrage proposals and also found useful in predicting the basin area of undefined barrage proposal for achieving economic viability. • Estimations made on the future possibility of revenue earnings from the by-products of various OTEC types, including the scope of chemical hubs from grazing type OTEC plants. • Determination of breakeven point- on cost versus life span of wave and OTEC devices studied, which is useful in designing optimum life of the concerned devices. The above stated multi-criterion assessment methodology, IAM, was extended leading to the development of a single criterion model for ascertaining sustainability percent achievable from an OE device and termed IAMs. The IAMs was developed identifying 7 Sustainability Development Indices (SDI) using some the tools of the IAM. A sustainability scale of 0-100 was also developed, attributing a Sustainability Development Load Score (SDLS) percentage distribution pattern over each SDIs, depending on their relative importance in achieving sustainability. The total sum of sustainability development (SD) gained from each SDI gave the IAMs (for the concerned device), indicating the total sustainable percentage achieved. The above IAMs developed, could be applied in ranking OE devices alongside the unsustainable coal power station. A mathematical model of estimating the IAMs was formulated, in order to ascertain the viability to the sustainable development of any energy device. The instruments of IAM and IAMs which have been developed would be helpful to the OE industry in ascertaining the degree of acceptability of their product. In addition it would also provide guidelines for their safe deployment by assessing the relative merits of competing devices. Furthermore, IAM and IAMs would be helpful to researchers undertaking feasibility studies on R&D efforts for material development research, ‘hybridization studies’ (as also new innovations), cost reduction, the performance improvement of respective devices, and any economic gains. With future advancements in OE systems and the availability of field data from large scale commercial applications, the specific values/data of the IAM & IAMs may be refined, but the logic of the models developed in this research would remain the same.
106

An analysis of the solar service provider industry in the Western Cape

Votteler, Roman Gunter 12 1900 (has links)
Thesis (MComm)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Scientists agree that the rising electricity usage of the rapidly growing human race to improve its standard of living is negatively affecting the environment. To create a sustainable environment for future generations, renewable and environmentally friendly resources have to be exchanged for the present finite resources. In South Africa, coal plants are responsible for more than 90% of the electricity production. This means that action has to be taken now to start a process of change to sustainable electricity resources. This study focused on the South African solar industry. Due to the high sun radiation levels, solar technology is one of the renewable energy sources with the greatest potential. The industry is in its infancy, characterised by accelerated growth expectancy and fuelled by factors such as government subsidies, the fluctuations of fossil fuel prices and the increasing focus on economical long-term sustainability. The expected growth necessitates a focus on the market positioning of solar service providers in the Western Cape with the aim of taking full advantage of the opportunities associated with this industry. The main objective of this study was to determine the current structure of the solar service provider value chain and subsequently areas of improvement to increase growth, stakeholder satisfaction and sustainability. A literature review was conducted to address the research objective, relevant approaches and the broader electricity industry. Porter’s Value Chain approach was used as a foundation for the adaptation to the solar service provider value chain. Porter’s Five Forces model was also used as a secondary approach, which analysed the competitive environment of the solar service provider industry in the Western Cape. The methodology entailed a qualitative research approach in the form of semi-structured interviews. All respondents were general managers or owners of a solar service provider, who were interviewed face to face. The study focused on the entire population of solar service providers in the Western Cape. Seventy-seven different service providers were targeted, of which 18 were interviewed. The interviews were transcribed and analysed using content and frequency analysis. To guarantee reliability, a pilot study was conducted to ensure that the questionnaire was understood by the respondents. The validity of this study is gauged as high as the entire population was targeted and the results can be broadly generalised. The findings show that customer service is the foremost value driver for solar service providers. This entails the actual installation of the product as well as the people skills of the installation team. As most customers only have to be served once due to the long life span of the products, marketing also plays an obvious role in attracting new customers. The most important outcome of this study is the determination and a better understanding of the solar service provider value chain in South Africa. The recommendations, especially with regard to marketing and service elements, could improve the performance of solar service providers. The consequence could be an increase in stakeholder satisfaction and an enhanced usage of solar energy in South Africa. Future research should focus on customers to reveal preferences and opportunities for marketing approaches. / AFRIKAANSE OPSOMMING: Wetenskaplikes is dit eens dat die snelgroeiende mensdom se stygende elektrisiteitsverbruik ten einde hul lewenstandaard te verhoog, die omgewing benadeel. Om ’n volhoubare omgewing vir toekomstige geslagte te skep, sal die huidige beperkte hulpbronne met hernubare en omgewingsvriendelike hulpbronne vervang moet word. In Suid-Afrika is steenkoolaanlegte verantwoordelik vir meer as 90% van die land se elektrisiteitsproduksie. Dít beteken dat daar nóú opgetree moet word om ’n proses van oorskakeling na volhoubare elektrisiteitshulpbronne aan die gang te sit. Hierdie studie konsentreer op die Suid-Afrikaanse sonenergiebedryf. Weens die hoë sonstralingsvlakke wat die land ervaar, is sonenergietegnologie een van die hernubare energiebronne met die grootste potensiaal. Die bedryf staan nog in sy kinderskoene en word gekenmerk deur ’n verwagting van al hoe vinniger groei, wat aangedryf word deur faktore soos staatsubsidies, skommelinge in fossielbrandstofpryse en ’n toenemende klem op ekonomiese langtermynvolhoubaarheid. Die verwagte groei noodsaak ’n ondersoek na die markplasing van sonenergiediensverskaffers in die Wes-Kaap ten einde die geleenthede verbonde aan hierdie bedryf ten volle te benut. Die hoofdoel van hierdie studie was om die huidige struktuur van die waardeketting van sonenergiediensverskaffers, en gevolglik ook moontlike verbeteringe vir groter groei, belanghebbende-tevredenheid en volhoubaarheid, te bepaal. ’n Literatuuroorsig is onderneem om die navorsingsoogmerk, tersaaklike benaderinge en die groter elektrisiteitsbedryf in konteks te beskou. Porter se waardekettingbenadering het as grondslag gedien vir aanpassing by die waardeketting van sonenergiediensverskaffers. Daarbenewens is Porter se model van vyf kragte as sekondêre benadering ingespan om die mededingende omgewing in die sonenergiediensverskaffersbedryf in die Wes-Kaap te ontleed. Die studiemetodologie het ’n kwalitatiewe navorsingsbenadering in die vorm van semigestruktureerde onderhoude behels. Alle respondente is algemene bestuurders of eienaars van ’n sonenergiediensverskaffer en het aan persoonlike onderhoude deelgeneem. Die studie het op die algehele populasie van sonenergiediensverskaffers in die Wes-Kaap gekonsentreer. Die teikengroep was 77 verskillende diensverskaffers, van wie 18 aan onderhoude deelgeneem het. Die onderhoude is getranskribeer en met behulp van inhouds- en frekwensie-analise ontleed. Betroubaarheid is gewaarborg deur middel van ’n loodsstudie om te verseker dat die respondente die vraelys sou verstaan. Aangesien die hele populasie as teikengroep gedien het en die resultate dus in die breë veralgemeen kan word, word hierdie studie as uiters geldig beskou. Die bevindinge toon dat kliëntediens die grootste waarde-aandrywer vir sonenergiediensverskaffers is. Dít behels die praktiese installering van die produk sowel as die mensevaardighede van die installasiespan. Aangesien die meeste kliënte weens die lang gebruiksduur van die produkte slegs een maal bedien hoef te word, speel bemarking ook ’n voor die hand liggende rol om nuwe kliënte te lok. Die belangrikste uitkoms van hierdie studie is die bepaling en beter begrip van die waardeketting van sonenergiediensverskaffers in Suid-Afrika. Die aanbevelings, veral met betrekking tot bemarkings- en dienselemente, kan sodanige verskaffers se prestasie verbeter. Dít kan weer tot groter belanghebbende-tevredenheid sowel as meer sonenergie-aanwending in Suid-Afrika lei. Toekomstige navorsing behoort op kliënte te konsentreer om hulle voorkeure, en dus ook moontlike bemarkingsgeleenthede, te bepaal.
107

Overcoming energy constraints on future development in Stellenbosch through energy efficiency : retrofitting of solar hot water heaters and gas stoves in middle and high income households in the residential sector

Nyabadza, Munyaradzi Christine 03 1900 (has links)
Thesis (MPhil)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: South Africa faces an energy crisis which presents itself in two forms; electricity generation dominated by coal fired power stations and current electricity supply capacity being unable to meet growth in demand. South Africa urgently requires new generation capacity: however, power stations take time to plan, construct and commission, meaning that South Africa has to consider other options to meet electricity demand. This necessitates quick and innovative ways of meeting future demand. Energy efficiency has been identified as “a low hanging fruit” on the energy tree to address supply constraints and reduce energy related greenhouse gas emissions. There are various energy efficiency programmes aimed at raising awareness of measures that households can take to reduce energy consumption. Some of South Africa’s key objectives of energy efficiency in the residential sector are to mitigate the effect of peak demand on power capacity and to introduce state of the art technologies. In terms of these technologies, there is an overlap between energy efficiency and renewable energy. The widespread installation of renewable energy technologies such as SWHs has the potential to delay the need to construct new power stations. SWHs are a viable renewable energy option for South Africa. It is a mature and proven technology with the potential to address South Africa’s electricity capacity problems. Not only does a SWH provide financial savings to the customer in the long run but it offers the additional benefit of a reduction in greenhouse gas emissions to society. Although awareness of the benefits of solar water heaters is increasing, SWH uptake remains low. However the uptake is increasing due to; a SWH rebate offered through Eskom, electricity price increases which are forcing consumers to seek alternatives and a national building code requiring energy efficient water heating in new buildings which is expected to come into effect in 2012. Liquid Petroleum Gas is a low carbon emitting source of fuel for cooking. In South Africa, middle–high income households rely on the electric stove for cooking. Cooking contributes to electricity peak demand. Reducing electricity demand by replacing the electric stove would help in reducing electricity peak demand from the grid. LPG use has been increasing due to the following reasons; electricity supply shortages, shifting government policy on LPG and increasing electricity tariffs forcing lifestyle changes. This case study sought to investigate the opportunities, as well as the barriers for a Stellenbosch municipality - initiated energy efficiency programme. In terms of energy supply and demand management, the municipality has identified energy efficiency and the introduction of renewable energy sources as options for achieving sustainability. One of the barriers facing energy efficient technologies is up-front costs in the case of SWHs and the cost of appropriate equipment such as gas stoves in the case LPG. The study sought to investigate financial mechanisms that the municipality could use to overcome these barriers and promote the use of SWH and gas stove in the residential sector. Data was collected through a combination of a mini Delphi – expert opinion technique, questionnaires, secondary data analysis, telephone and personal interviews with solar water heater industry stakeholders, LPG industry stakeholders and municipal officials. The conclusion drawn from this research is that Stellenbosch Municipality can initiate its own energy efficiency programme instead of waiting for national government. Although the municipality can initiate an energy efficiency programme, it needs to find another institution to fund the programme. Funding mechanisms however do overcome the barrier of high up -front costs and high gas equipment costs making energy efficient technologies affordable. / AFRIKAANSE OPSOMMING: Suid-Afrika staan voor ʼn energiekrisis wat op twee maniere gestalte kry: elektrisiteitsopwekking wat oorheers word deur steenkoolkragstasies en huidige elektrisiteitsvoorsieningsvermoë wat nie in die groeiende aanvraag kan voorsien nie. Suid-Afrika benodig dringend nuwe kragontwikkelingsvermoë. Dit neem egter tyd om kragstasies te beplan, op te rig en in diens te stel, wat beteken dat Suid-Afrika ander opsies moet oorweeg om in elektrisiteitsaanvraag te voorsien. Dit noodsaak vinnige en innoverende maniere om in toekomstige aanvraag te voorsien. Energierendement is as “ʼn laaghangende vrug” op die energieboom geïdentifiseer ten einde beperkings in kragvoorsiening die hoof te bied en kweekhuisgasuitlatings wat met energie verband hou te verminder. Daar is verskeie energiebesparingsprogramme wat ten doel het om die bewustheid te versterk van maatreëls wat huishoudings kan volg om energieverbruik te verminder. Van Suid-Afrika se vernaamste doelstellings ten opsigte van energierendement in die residensiële sektor is om die uitwerking van spitsaanvraag op kragvermoë te verlig en om die jongste tegnologie in te voer. Ingevolge hierdie tegnologieë is daar ʼn oorvleueling tussen energierendement en hernubare energie. Die algemene installering van hernubare energietegnologieë, soos sonkragwaterverwarming (SWV), het die potensiaal om die noodsaaklikheid van die oprigting van nuwe kragstasies uit te stel. SWV is ʼn lewensvatbare nuwe energieopsie vir Suid-Afrika. Dit is ʼn ontwikkelde en bewese tegnologie met die potensiaal om Suid-Afrika se probleme ten opsigte van elektrisiteitsvermoë die hoof te bied. SWV sorg nie slegs vir die kliënt vir finansiële besparing op die lang duur nie, maar dit bied ook vir die samelewing die bykomende voordeel van ʼn afname in kweekhuisgasuitlatings. Alhoewel die bewustheid van die voordele van sonkragwaterverwarming toeneem, bly die gebruik van SWV laag. Die gebruik is egter besig om toe te neem vanweë ʼn SWV-korting wat deur Eskom aangebied word, elektrisiteitsprysverhogings wat verbruikers dwing om alternatiewe te soek, en ʼn nasionale boureglement wat energiedoeltreffende waterverwarming in nuwe geboue vereis en wat na verwagting in 2012 in werking sal tree. Vloeibare petroleumgas is ʼn brandstofbron wat vir kook gebruik word en wat ʼn lae koolstofvrystelling het. In Suid-Afrika gebruik huishoudings met ʼn middelhoë inkomste die elektriese stoof om te kook. Kook dra by tot elektrisiteitspitsaanvraag. Die vermindering in elektrisiteitsaanvraag deur die vervanging van die elektriese stoof kan help om die elektrisiteitspitsaanvraag op die netwerk te verlaag. Die gebruik van VPG het toegeneem weens die volgende redes: elektrisiteitsvoorsieningstekorte, veranderende regeringsbeleid ten opsigte van VPG en die verhoging in elektrisiteitstariewe wat veranderinge in lewenstyl afdwing. Hierdie gevallestudie het gepoog om die geleenthede, sowel as die hindernisse vir ʼn energierendementprogram wat deur Stellenbosch Munisipaliteit geïnisieer is, te ondersoek. Ten opsigte van energievoorsiening en -aanvraagbestuur het die munisipaliteit energierendement geïdentifiseer en die ingebruikneming van hernubare-energiebronne as opsies om volhoubaarheid te bereik. Een van die hindernisse waarvoor energierenderende tegnologieë te staan kom, is voorkostes in die geval van SWV en die koste van toepaslike toerusting soos gasstowe in die geval VPG. Die studie het ondersoek ingestel na die finansiële meganismes wat die munisipaliteit sou kon gebruik om hierdie hindernisse te bowe te kom en die gebruik van SWV en gasstowe in die residensiële sektor te bevorder. Data is ingevorder deur middel van ʼn kombinasie van ʼn mini-Delphi – kennermeningtegniek, vraelyste, sekondêre data-ontleding, telefoon- en persoonlike onderhoude met belanghebbendes in die sonkragwaterverwarmingsbedryf, belanghebbendes in die VPG-bedryf en munisipale amptenare. Die gevolgtrekking wat uit hierdie navorsing gemaak word, is dat Stellenbosch Munisipaliteit sy eie energierendementprogram kan inisieer in plaas daarvan om vir nasionale regering te wag. Alhoewel die munisipaliteit ʼn energierendementprogram kan inisieer, moet dit ʼn ander instelling kry om die program te befonds. Befondsingsmeganismes oorkom egter die struikelblok van hoë voorkostes en hoë kostes van gastoerusting wat energierenderende tegnologieë bekostigbaar maak.
108

Economic feasibility study for the wave energy technology of Gaia Power Group Pty Ltd

Schneider, Bettina 12 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2011. / Gaia Power is a South African start-up in the renewable energy industry. Among other products, they developed a wave energy converter, which is a device used to extract energy from ocean waves. This research deals with the economic feasibility study of the wave energy converter. Wave energy is a young field of research, especially in the South African context. Therefore sources for multiple angles of the project had to be found, analysed and brought into the Gaia Power context. Understanding the cost drivers of a wave energy plant was the foundation of the research itself. The Gaia Power specific levelised cost of electricity generation was calculated based on actual supplier quotes, reference costs found in the literature as well as assumptions. Still, such a calculation is actually more an estimation due to a high uncertainty level in all cost components. Especially the construction cost as well as the discount rate used have therefore been tested for sensitivity. Gaia Power‟s target production cost was R0.54 kWh, which equalled the Eskom tariff at the time of this research. Taking into account a R0.10/kWh fee payable to Eskom, the target cost sank to R0.44, which is about 25 percent lower than the minimum value for electricity generation cost found in the literature. This target was therefore expected to be and proved to be difficult to reach. The calculated levelised electricity cost was R0.99/kWh, with a possible range of R0.54/kWh to R1.60/kWh observed in the sensitivity analysis. These results show that the Gaia Power wave energy converter in the given specifications was not economically feasible. It was therefore recommended to rethink the specifications in order to reduce construction cost, which proved to be the largest cost driver. Besides the quantitative findings, this research also has a strong qualitative side. During the whole research it became obvious that there was an overall high risk level in the project due to the lack of experience with wave energy in general and in South Africa specifically, as well as the high impact of weather on the construction. Those risks were identified, analysed and recommended mitigation actions were derived.
109

Risk management strategies and portfolio analysis for electricity generation planning and integration of renewable portfolio standards

Ritter, Stephanie Michelle 27 October 2010 (has links)
Renewable Portfolio Standards (RPS) require electricity providers to supply a minimum fixed percentage or total quantity of customer load from designated renewable energy resources by a given date. These policies have become increasingly prevalent in the past decade as state governments seek to increase the use of renewable energy sources. As a policy tool, RPS provide a cost-effective, market-based approach for meeting targets which promote greater use of renewable energy in both regulated and deregulated markets. To facilitate the obtainment of Renewable Portfolio Standards, most states allow the trading of Renewable Energy Credits (RECs). RECs represent the environmental attributes of renewable energy generation which are decoupled from the generated power. These credits are created along with the generation of renewable energy, decoupled from energy generation, tracked by regional systems, and eventually purchased by retail suppliers to fulfill their RPS obligations. As of April 2010, RPS have been passed into law in 29 states and Washington D.C. and an additional 6 states have non-mandatory renewable portfolio goals however the U.S. government has yet to enact a Federal Renewable Portfolio Standard. Although the final requirements and details of a Federal RPS are undecided, federal standards would be unlikely to preempt or override state programs which are already in place. A key concern regarding the passage of a federal RPS is that a national REC market would result in a shift of wealth from states with few renewable energy resources and limited resource potential to regions richer in renewable resources. Because of the implications that a federal renewable portfolio standard would have on the economy, the environment, and the equitable treatment of all the states, many issues and concerns must be resolved before federal standards will be passed into law. A theoretical case study for an electric utility generation planning decision that includes obligations to meet Renewable Portfolio Standard is presented here. A framework is provided that allows decision makers and strategic planning teams to: assess their business situation, identify objectives of generation planning, determine the relative weights of the objectives, recognize tradeoffs, and create an efficient portfolio using Portfolio Theory. The case study follows the business situation for Austin Energy as it seeks to meet Texas State RPS and mandates set by Austin City Council and prepares for potential National RPS legislation. / text
110

復合互賴下的合作:中國與東協在資源上的合作開發 / Cooperation under Complex Interdependence: China - ASEAN Relations in the Joint Development of Resources

李儒思, Linus Scherrer Unknown Date (has links)
The traditional explanation of the rapprochement between China and ASEAN has two elements: China is securing a peaceful environment to implement its strategy of ‘develop first’, and/or China is engaging in courtship for the ASEAN countries out of strategic considerations, i.e. increasing control of its periphery. In contrary to these traditional perspectives, this study argues that the intensifying of cooperation between China and ASEAN is much more an expression of the recognition of asymmetrical dependencies than of calculated foreign policy decisions. This perspective not only enriches the understanding of current regional political processes but also leads to different expectations regarding the stability and future direction of ASEAN – China relations. Two issue areas have been selected to illustrate the asymmetrical dependencies and the resulting political processes between ASEAN and China. It has been found that both the ASEAN countries and China have accommodated to asymmetrical interdependence by engaging in pay-offs in areas of relative power. China has not been able to use its relative power in the economic and military area to impose its will in other areas of ASEAN-China relations. The bargaining has taken place within the existing ASEAN institutions. In their concrete rules and conventions lies considerable power. This explains the intensive bargaining regarding the importance of competing international organizations, not only in the Mekong River Basin, but also in broader regional politics. The ASEAN countries are in a favorable position, being in the center of these institutions, but China as a latecomer to many of the regional institutions is trying to renegotiate them. Further research is therefore indicated to better understand how the ASEAN countries and China are going to trade off potential gains from international cooperation and the loss of sovereign policy making power.

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