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Access to electricity in sub Saharan Africa : modelling the importance and adoption of off-grid renewablesAbdul-Salam, Yakubu January 2014 (has links)
Many settlements in Sub Saharan Africa (SSA) lack access to electricity which is a necessary resource for development. Given the geography and population patterns in the region, extending national grids is economically unviable for many of the un-electrified settlements. Meanwhile the region is endowed with renewable resources which can be exploited in off-grid mode for electricity generation. This thesis examines the importance of off-grid technologies for onward electrification in the SSA region. The exercise inspires an electricity planning problem that can be analytically specified but is computationally intensive and impractical for real sized problems. Heuristic methods must therefore be used. We develop two new heuristic solution methods which draw on standard algorithms i.e. lexicographic algorithm and genetic algorithm to solve the problem. The new solution methods together with two existing heuristic algorithms in the literature are applied to a case study of Ghana. We find that the electrification schemes yielded by all four solution methods/algorithms suggest off-grid technologies, especially solar, are important for onward electrification in SSA. Locations that were assigned off-grid technologies in the algorithms mentioned above are typically rural where livelihoods are based on small scale farming. Currently, adoption of renewable resource technologies is low in these locations. We therefore develop a dynamic stochastic farm household model to examine the extent to which market failures impact self-funded investment in solar panels by farmers in rural SSA. We find that credit restrictions and risk affect solar panel investment to varying degrees. Using simulations of the policy functions, we find that the expected investment cycle for a credit constrained household in a stochastic farm income environment is 30 years if investment in solar panels is irreversible. In a reversible investment scenario, the expected investment cycle is 5 years only. Reversibility is therefore a major determinant of solar panel adoption among poor farmers.
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A comparative analysis of renewable energy financing models in Brazil, China, India and South AfricaKamara, Rivhatshinyi Nicole January 2016 (has links)
Thesis submitted in fulfilment of the requirements for the degree of Master of Management in Finance & Investment in the Faculty of Commerce Law and Management Wits Business School, Johannesburg 2016 / This thesis reviewed research papers, reports, conference documents and policy documents that looked at financial models used to finance RE projects in Brazil, China, India and South Africa.The comparison between the financing models revealed the following; Both Brazil and China’s financing model is a centralised government led model which might not necessarily work in the South African context. The India decentralised model is similar to the South African model, with the exception that corporate finance is widely used in India and Project Finance in South Africa. Thus there are lessons to be learnt from each country, however no single country financing model was found to be suitable for South Africa.
Accordingly, this paper therefore recommends that South Africa’s model be altered to incorporate project bonds. The use of these bonds in the current financial model will ensure that banks are able to lend to projects on short term basis; thus, managing their liquidity and their asset--liability effectively. Further, some institutional investors have shown an interest in funding projects at the construction stage, and the inclusion of project bonds would ensure that more of these investors play a role in financing projects.
Key Words GDP-Gross Domestic Product; GW- Gigawatts; DoE-Department of Energy; REIPPPP- Renewable Energy Independent Power Producer Procurement Programme; BEE-Black Economic Empowerment; RE-Renewable Energy; SSA-Sub Saharan Africa; PPA-Power Purchase Agreement; FIT-Feed In Tariff; DFIDevelopment Finance Institution; MDB-Multilateral Development Bank / GR2018
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Desenvolvimento de um método para a determinação de acilgliceróis em biodiesel utilizando cromatografia líquida de alta eficiência com detecção eletroquímica /Ballottin, Daniela Pott Marinho. January 2011 (has links)
Orientador: Nelson Ramos Stradiotto / Banca: Marcelo Firmino de Oliveira / Banca: André Luiz dos Santos / Resumo: A alta demanda de energia no mundo atual, bem como o grande número de problemas ambientais existentes, resultam em uma crescente necessidade por novas fontes de energia, estimulando assim o interesse por fontes alternativas para os combustíveis de origem fóssil. Surge então o Biodiesel, combustível biodegradável derivado de fontes renováveis. No entanto, este biocombustível apresenta certos contaminantes que podem causar sérios danos ao motor e ao ambiente dependente de seus teores. Dentre estes, estão os acilgliceróis, remanescentes da matéria prima para a produção do biodiesel. Por exemplo, a alta concentração destes compostos aumenta a viscosidade do biocombustível, provocando depósitos nos cilindros e nas válvulas diminuindo assim a vida útil do motor. Assim, foi avaliado neste trabalho o comportamento voltamétrico do mono, di e trilinoleato de glicerina através da técnica de Redissolução Adsortiva com Voltametria AC. As curvas analíticas para o mono e trilinoleato de glicerina apresentaram linearidade de 4,0 x 10-8 a 1,6 x 10-6 mol L-1, com limites de detecção da ordem de 10-8 mol L-1. A curva analítica do dilinoleato de glicerina mostrou-se linear de 4,0 x 10-9 a 4,0 x 10-7 mol L-1, com limite de detecção da ordem de 10-9 mol L-1. Os limites de quantificação foram da ordem de 10-8 mol L-1 para o mono e o dilinoleato de glicerina e 10-7 mol L-1 para o trilinoleato de glicerina. Porém, estes não puderam ser determinados simultaneamente e, por isso, utilizou-se um método cromatográfico com detecção eletroquímica para a separação e posterior detecção destes compostos. Os acilgliceróis foram separados em coluna de fase reversa (C-18) operando em modo isocrático com fase móvel tampão fosfato pH 3,0/MeOH 60:40 (v/v) com adição de ácido ascórbico / Abstract: Currently, the high energy demand in today's world, as well as the environmental problems result in an increased need for developing renewable energy sources, thereby stimulating interest in alternative sources to fossil fuels. Then, Biodiesel comes as a biodegradable fuel derived from renewable sources. However, this biofuel has certain contaminants that can cause serious damage to the engine and the environment if they are present in inadequate amounts. Among these contaminants are the glycerides, remnants of the raw material for biodiesel production. For example, the high concentration of these compounds increases the viscosity of the biofuel causing deposits in the cylinders and valves reducing the engine lifetime. Thus, it was evaluated in this study the voltammetric behavior of glyceryl mono, di and trilinoleate by Adsorptive Stripping technique with AC voltammetry. The analytical curves for mono and tri showed linearity from 4.0 x 10-8 to 1.6 x 10-6 mol L-1, with detection limits of about 10-8 mol L-1. The analytical curve of glyceryl dilinoleate was linear from 4.0 x 10-9 to 4.0 x 10-7 mol L-1, with a detection limit of about 10-9 mol L-1. The quantification limits were in the order of 10-8 mol L-1 for mono and dilinoleate and 10-7 mol L-1 for trilinoleate. However, these could not be determined simultaneously and therefore it was developed a chromatographic method with electrochemical detection for separation and detection of these compounds. The glycerides were separated on a reversed phase column (C-18) operating in isocratic mode with mobile phase pH 3.0 phosphate buffer / MeOH 60:40 (v/v) with addition of ascorbic acid / Mestre
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Sustainable agriculture, renewable energy and rural development an analysis of bio-energy systems used by small farms in China /Zhou, Aiming. January 2006 (has links)
Thesis (Ph.D.)--University of Delaware, 2006. / Principal faculty advisor: John Byrne, School of Urban Affairs & Public Policy. Includes bibliographical references.
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Integration of renewable energy sources: reliability-constrained power system planning and operations using computational intelligenceWang, Lingfeng 15 May 2009 (has links)
Renewable sources of energy such as wind turbine generators and solar panels
have attracted much attention because they are environmentally friendly, do not
consume fossil fuels, and can enhance a nation’s energy security. As a result, recently
more significant amounts of renewable energy are being integrated into conventional
power grids. The research reported in this dissertation primarily investigates the
reliability-constrained planning and operations of electric power systems including
renewable sources of energy by accounting for uncertainty. The major sources of
uncertainty in these systems include equipment failures and stochastic variations in
time-dependent power sources.
Different energy sources have different characteristics in terms of cost, power
dispatchability, and environmental impact. For instance, the intermittency of some
renewable energy sources may compromise the system reliability when they are integrated into the traditional power grids. Thus, multiple issues should be considered in
grid interconnection, including system cost, reliability, and pollutant emissions. Furthermore, due to the high complexity and high nonlinearity of such non-traditional
power systems with multiple energy sources, computational intelligence based optimization methods are used to resolve several important and challenging problems in
their operations and planning. Meanwhile, probabilistic methods are used for reliability evaluation in these reliability-constrained planning and design.
The major problems studied in the dissertation include reliability evaluation of
power systems with time-dependent energy sources, multi-objective design of hybrid
generation systems, risk and cost tradeoff in economic dispatch with wind power penetration, optimal placement of distributed generators and protective devices in power
distribution systems, and reliability-based estimation of wind power capacity credit.
These case studies have demonstrated the viability and effectiveness of computational
intelligence based methods in dealing with a set of important problems in this research
arena.
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Venezuela : a petro-state using renewable energies : a contribution to the global debate about new renewable energies for electricity generation /Massabié, Germán. January 2008 (has links)
Zugl.: Berlin, Freie Univ., Diss., 2003. / With a German abstract. Includes bibliographical references.
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Design of a laboratory rig to determine slagging of biomass fuels /Gilfillan, William N. January 2001 (has links) (PDF)
Thesis (M. Eng. Sc.)--University of Queensland, 2002. / Includes bibliographical references (p. 141).
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An education and research centre on renewable energy /Mok, Hei-lun, Allen. January 2001 (has links)
Thesis (M. Arch.)--University of Hong Kong, 2001. / Includes special report study entitled: An education and research centre on renewable energy. Includes bibliographical references.
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Electrochemical conversion of aluminum energy: energy efficiency, co-production concept and systemcharacteristicsWang, Huizhi, 王慧至 January 2011 (has links)
published_or_final_version / Mechanical Engineering / Doctoral / Doctor of Philosophy
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Μελέτη και κατασκευή συστήματος υβριδικού Α.Π.Ε. μικρής ισχύος αιολικής και φωτοβολταϊκής διάταξηςΓιακουμής, Ιάκωβος 25 May 2009 (has links)
Σκοπός της παρούσας εργασίας είναι η πειραματική μελέτη διατάξεων μετατροπής αιολικής και ηλιακής ενέργειας σε ηλεκτρική.
Αρχικά, στην εργασία αναλύονται οι κυριότερες ανανεώσιμες πηγές ενέργειας (Α.Π.Ε.), με μικρές αναφορές στο κάθε σύστημα ξεχωριστά.
Στη συνέχεια της εργασία, εξηγείται το φαινόμενο της δημιουργίας ανέμων στην ατμόσφαιρα, τονίζεται ο σημαντικός ρόλος που έπαιζε ο άνεμος από τα αρχαία χρόνια, παρατίθεται μια σύντομη ιστορική αναδρομή, αναλύονται τα μέρη της ανεμογεννήτριας, επισημαίνονται τα πλεονεκτήματα και τα μειονεκτήματα της ενέργειας που παράγεται από τον άνεμο. Τέλος αναφέρονται κάποιες αποθηκευτικές διατάξεις και στη συνέχεια αναλύονται περιληπτικά οι συσσωρευτές, αφού στο σύστημα μας υπάρχει χρήση συσσωρευτών.
Επιπλέον, αναφέρουμε τα βασικά στοιχειά για ένα μετεωρολογικό σταθμό, τον οποίο και δημιουργήσαμε για το σκοπό της παρούσας διπλωματικής εργασίας.
Στη συνέχεια έχουμε την επεξήγηση του τρόπου εγκατάστασης της ανεμογεννήτριας την οποία απέκτησε το εργαστήριο για σκοπούς μελέτης. Επιπλέον επεξηγείται η κατασκευή ορισμένων κυκλωματικών διατάξεων, μέσω των οποίων γίνεται δυνατός ο έλεγχος της ανεμογεννήτριας όπως επίσης και η μέτρηση, καταγραφή, αποθήκευση τεσσάρων βασικών στοιχειών (ταχύτητα ανέμου, διεύθυνση ανέμου, τάση και ρεύμα στο φορτίο) τα οποία θα μας βοηθήσουν στη συνέχεια της διπλωματικής ώστε να δημιουργήσουμε ανεμολογικά δεδομένα για την περιοχή του Πανεπιστημίου Πατρών, όπως επίσης και για την κατασκευή της καμπύλης φόρτισης της ανεμογεννήτριας του Εργαστηρίου Η.Μ.Ε. Ταυτοχρόνως με τις ίδιες κυκλωματικές διατάξεις έχουμε τη δυνατότητα να λαμβάνουμε δεδομένα από τα οποία μετά από επεξεργασία μπορούμε να λάβουμε την παραγόμενη ενέργεια από το κάθε σύστημα, ενώ παρουσιάζονται οι πειραματικές καμπύλες οι οποίες έχουν εξαχθεί από τα πειραματικά δεδομένα της διπλωματικής.
Το επόμενο μέρος της διπλωματικής μου εργασίας αναφέρετε στα ηλιακά ΦΒ-συστήματα, αναφέροντας τα βασικότερα μεγέθη τα οποία επηρεάζουν την απόδοση τους. Επίσης αναφέρονται οι βασικότεροι τύποι υλικών κατασκευές ΦΒ-στοιχειών για τα οποία αναφέρουμε τις βασικότερες παραμέτρους τους. Αναφέρουμε επίσης κάποια πειραματικά συστήματα τα οποία προσπαθούν να αυξήσουν την παραγωγή ενέργειας από τα ΦΒ. Μετά ακολουθούν οι γραφικές παραστάσεις των πειραματικών αποτελεσμάτων τα οποία έχουμε πάρει από τις πειραματικές μας διατάξεις.
Τέλος, γίνεται μια προσπάθεια να αναπτύξουμε ένα μαθηματικό μοντέλο με τα οποίο προσπαθούμε να δώσουν απάντηση στο ερώτημα, αν συμφέρει η όχι από οικονομικής άποψης, το θέμα της επένδυσης χρημάτων σε ΦΒ-σταθμούς. / -
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