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In 2010, the adoption of nuclear power was declared a national priority in Kenya. Thereafter, a target of obtaining 4000 MW of nuclear power by the year 2030 was documented in Kenya's Least Cost Power Development Plan (LCPDP) 2010-2031. The nuclear target has drawn a lot of opposition from some Kenyans whose concerns are centered on the cost and safety risks incurred by nuclear power. The government however states that nuclear power is necessary for the diversification of the electricity generation mix and satisfaction of future electricity demand. The aim of this thesis was therefore to determine whether electricity demand in Kenya could be met without nuclear power and whether it was more economical to utilize nuclear power in Kenya's electricity generation mix rather than increase the generation capacity of other sources of electricity available to Kenya. To answer these questions, two capacity expansion models were developed. These models like the LCPDP studied the period between 2010 and 2031. The aim of the first model was to replicate LCPDP, and in doing so verify the necessity of nuclear power for meeting Kenya's future electricity demand. As far as was possible, the validation model utilized the same assumptions, including the same demand forecast that was used to develop the LCPDP 2010-2031. The validation was done to verify the necessity of nuclear power from the LCPDP's set of assumptions. The second model was developed with the aim of obtaining an updated capacity expansion plan. This plan utilized recent assumptions including an updated demand forecast. The demand was forecasted using regression of historical electricity demand against GDP in the commercial and industrial category. In the domestic category historical demand was regressed against GDP per capita and population. Based on recent data and economic forecasts, a GDP growth rate of 6% was used to forecast the electricity demand instead of 9% used in the LCPDP's demand forecast. [Please note: this thesis file has been deferred until June 2018]

This thesis presents a study of the technical, economic and social appropriateness of small stand-alone photovoltaic (PV) systems for meeting minimal electrical requirements in low-income off-grid households. A comprehensive review of the literature on photovoltaic technology was undertaken to identify key theoretical parameters and issues, and also to determine what the experience has been of similar applications in third world countries. Two PV systems were installed as demonstration projects: one at Uitsig near Cape Town, and the other at Omdraaisvlei in the Northern Cape. In order to monitor and evaluate the techriical performance of these systems, remote data capture units were installed for measuring appropriate parameters for analysis on typical daily, weekly and monthly bases. The degree of matching between the PV output characteristics and the battery and load demand was examined as weLl as the costs of system and component efficiencies under different operating conditions. The economic evaluation aimed to compare small PV systems with these of alternative power systems, for example petrol generators. Using a life cycle costing methodology (discounted to present value) the least-cost option for small power systems was determined under a range of financial scenarios. The social evaluation aimed at determining the impact of PV power on peoples' lifestyles. The results of the two demonstration projects have shown that photovoltaics can appropriately meet small domestic power needs in off-grid applications, providing clean, reliable, maintenance-free electricity which is far more convenient than other electricity producing technologies. Photovoltaics proved to be very much more cost effective than petrol generators, and were also found to be cheaper than coventionally used energy sources such as paraffin, candles and batteries. Both of the demonstration project households were extremely satisfied with the PV systems, which have resulted in significant improvement in quality of lifestyles. However, based on the overall performance of the systems it was recommended that more research was needed, using local conditions, and data to develop better PV system design and sizing methodologies.

Bibliography: pages 58-59. / This report describes a computer program which has been developed to simulate accurately the performance of stand alone photovoltaic systems with battery storage on an hourly basis for one simulated year. The program incorporates models of the POA irradiance, the photovoltaic cell · temperature and the battery temperature to simulate the environmental conditions of the system. These require hourly weather data as input. Typical meteorological years, which constitute a suitable form of input weather data, have been generated for those weather stations in Southern Africa which contain sufficient data. The energy flows within the system are simulated using models of the following parameters: photovoltaic module current, regulator efficiency and voltage, battery current and voltage, inverter efficiency, load shed voltage and load current. These models incorporate versatility in the level of modelling complexity (determined typically by the availability of the data used to characterise the components). The various models are encapsulated in modular units to facilitate alteration and updating at a later stage. The program is designed to simulate photovoltaic systems without maximum power point trackers, necessitating the use of interactive curve solving to compute the system operating point at any time. A robust and comprehensive algorithm has been implemented to execute this function. Improved battery modelling has been effected using data and experience acquired from a parallel research project. The program facilitates, with the judicious selection of input weather data, the economical sizing of systems in that it incorporates loss of power probability analysis and offers a high level of modelling precision. The simulation performance of the program compared favourably with that of PVFORM. The system performance estimated by PVFORM was marginally better, which is expected because PVFORM assumes that the system operates with a maximum power point tracker. In the development of the program there has been a focus on creating an effective user interface. This is designed to simplify and speed up program operation, and to present output in a form which is useful and illustrative.

A software tool for assisting in the preliminary performance modelling of central receiver solar thermal plants was developed using Matlab®. Scope was limited to the thermodynamic study of the power cycle and receiver. The receiver model was validated by comparing results to published data. The model was able to simulate billboard, C-cavity and cylindrical receivers within 1% in cases involving single-phase fluids and by at most 3% - 5% for water. Performance studies were conducted to demonstrate the usefulness of the model. Power cycle studies investigated the performance limits on non-reheated cycles as well as the effects of reheat and regenerative feedwater heating. The results showed expected trends of efficiency increasing with turbine inlet temperature and pressures. Also, efficiency was shown to increase asymptotically with number of feedwater heaters and reheat was shown to improve exhaust quality and efficiency. Billboard and cylindrical receivers were studied in detail using a number of heat transfer fluids, namely thermal oil, molten salt, molten sodium and water to compare the relative performance over a range of rated powers. Water and thermal oil were shown to be the best performing fluids for use in billboards and cylindrical receivers, respectively. Water and salt were shown to require the least area for use in billboards and cylindrical receivers, respectively. The effects of power cycle performance on receiver performance and size were investigated from which it was found that receiver efficiency increases marginally with power cycle efficiency but the required area is reduced significantly.

This paper considers the opportunities for the South African and Zimbabwean Saw-milling Industry to be self-sufficient in the generation of power for its own industrial electrical energy requirements. The analysis of the wood residue arising from saw-milling operations in the southern African context confirms that there is a substantial amount of fuel available for the main heating requirement of a wet saw-mill. This heat is generally supplied in the form of steam to the timber drying and conditioning kilns that form part of the timber production process. One of the principal arguments put forward for cogeneration is that by passing steam through a condensing or back pressure turbine the entire power demand of a saw-mill can be met as well as the heat for the kilning process. Due to the situation of unbalanced load that persists at nearly all the saw-mills, there is a surplus of power that is often difficult to dispose of economically.

The climate change negotiations under the United Nations Framework Convention on Climate Change have been ongoing since the first conference of the parties in 1995. Twenty years on there has been little progress reducing greenhouse gas emissions, the climate regime is in a state of flux and the role of developing countries therein is changing. During this period the majority of the work on climate change from within the International Relations discipline has been framed in a neoliberal institutionalist or neorealist frame. Studies in the climate policy canon have been predominantly similarly located, albeit implicitly. In its focus on India this dissertation provides a bridge between the climate policy literature and the theoretically framed climate change policy studies in the International Relations literature. This dissertation employs the Critical International Relations theoretical framework of Robert Cox. His theory outlines a 'framework for action' that enables and constrains how states act, and how they conceive of their agency. This framework, or historical structure, is created by a particular configuration of the forces exerted by ideas, institutions, and material capabilities, which when aligned, create a hegemonic historical structure. In the climate negotiations, India has been a vocal proponent of the ideas of equity and common but differentiated responsibilities from the earliest days of the Convention. India's changing material circumstances and geo-political status in the past decade raised the question of its role in the regime in relation to its long-supported ideas. This is a qualitative case study using documentary evidence triangulated with interview data from a range of key Indian stakeholders. I found that in the transition from abstract principle to operational precept the intersubjective idea of addressing climate change did not transmute into an intersubjectively shared idea of differentiation. Furthermore, once the idea of differentiation was to be operationalised in the negotiations, its primacy, indeed its very "intersubjectiveness", was contested by the idea of symmetry of obligations and responsibility. The ongoing regime flux is the outcome of this contestation between ideas held collectively by groups, as no stabilising hegemonic historical structure has been created. India's emergence has been insufficient to reinstate differentiation as an intersubjectively held idea and it is thus unable to secure a hegemonic historical structure in favour of differentiation.

This thesis explores the basic theory, design and construction of electron spin resonance spectrometer.

Research on renewable energy must be hastened to solve the energy crisis we are now facing. Among all sustainable energy sources, solar energy and hydrogen gas fuel are two of the most clean and powerful. Photo-electrochemical (PEC) reactions use solar energy to electrochemically split water to produce hydrogen gas. Photoelectrocatalyst materials play an important role in increasing the e ciency of PEC reactions by absorbing solar energy and directing the energy towards the desired electrochemical reactions. Two-dimensional (2D) layered materials including MoS2, WS2, and SnS2 have drawn considerable attention as electrocatalysts and photo-electrocatalysts because of the catalytically-active nature of their edges and high charge mobility and transport e ciency within their layers. This work focuses on the synthesis, measurement, and simulation of PEC properties and behavior of WS2 nanotubes and SnS2 nano akes. The rst part of this work focuses on experimental synthesis and PEC measurement of edge-on oriented WS2 nanotubes and theoretical simulation of the atomic con guration and electronic structure of the edges by density functional theory (DFT) . WS2 nanotubes were synthesized by chemical vapor deposition (CVD) and sulfurization, but showed very poor photresponse. The DFT simulation shows the edges of the WS2 nanotubes are metallic, like those of 2H-MoS2. The metallic edges likely act as recombination sites for photogenerated charges, which explains the poor photoresponse of WS2. The second part of this work focuses on experimental synthesis and PEC measurement of edge-on oriented SnS2 nano akes and theoretical simulation by DFT. The edge-on oriented SnS2 nano akes exhibited high photoresponse and excellent PEC performance. The DFT simulation determined the atomic con gurations of SnS2 edges, and the stability of both bulk-like and monolayer SnS2 edges at various S potentials. In contrast to WS2 and MoS2, the DFT simulation also determined that the edges of SnS2 are semiconducting, not metallic. Therefore, the edges of SnS2 would not cause recombination of photoexcited charges, and would enable SnS2 to achieve a high photoresponse, as was experimentally observed. The DFT results also showed that the band gap energy of the SnS2 edges becomes smaller with increasing sulfur coverage, and allowed the in uence of chemical synthesis conditions on the electronic structure of the edges to be determined.

archives@tulane.edu / This thesis examines the qualitative behavior of solutions to a PDE model for chemotaxis; that is the existence, uniqueness and asymptotic behavior of solutions. We study initial-boundary value problems for a chemotaxis model with logarithmic sensitivity and logistic growth for the cell population density, and nonlinear growth of the chemical concentration. Extensive work has been done for this particular model without logistic growth on both bounded and unbounded domains. However, the model with logistic growth on a bounded domain has not been studied before. This case is of particular interest given its relevance for modeling tumor angiogenesis. We first establish global well-posedness of strong solutions for large initial data with no-flux boundary conditions and, moreover, establish the qualitative result that both the population density and chemical concentration asymptotically converge to constant states. The population density in particular converges to its carrying capacity. We additionally prove that the vanishing chemical diffusivity limit holds in this regime. Finally, we provide numerical confirmation of the rigorous qualitative results, as well as numerical simulations that demonstrate a separation of scales phenomenon. We then establish global well-posedness of strong solutions for large initial data with dynamic boundary conditions. Moreover, the solutions will asymptotically approach the boundary data under mild and natural assumptions on the boundary functions. We additionally show the formation of a boundary profile in the singular chemical zero diffusive limit. Lastly, we provide numerical simulations that confirm the boundary layer formation, as well as convergence towards certain steady states of the solution when relaxing the assumptions on the boundary data. The main tool developed in these results is a particular Lyapunov functional that helps overcome the mathematical challenges of the non-conservation of the mass due to the logistic growth. These results give a complete study of this particular system on bounded domains with both zero-flux and dynamic moving boundary conditions. / 1 / Padi Fuster Aguilera