Thermal energy storage (TES) systems play a crucial part in the success of concentrated solar power as a reliable thermal energy source. The economics and operational effectiveness of TES systems are the subjects of continuous research for improvement, in order to lower the localized cost of energy (LCOE). This study investigates the use of spherical tanks and their role in sensible heat storage in liquids. In the two tank system, typical cylindrical tanks were replaced by spherical tanks of the same volume and subjected to heat loss, stress analysis, and complete tank cost evaluation. The comparison revealed that replacing cylindrical tanks by spherical tanks in two tank molten salt storage systems could result in a 30% reduction in heat loss from the wall, with a comparable reduction in total cost. For a one tank system (or thermocline system), a parametric computational fluid dynamic (CFD) study was performed in order to obtain fluid flow parameters that govern the formation and maintenance of a thermocline in a spherical tank. The parametric study involved the following dimensionless numbers: Re (500-7500), Ar (0.5-10), Fr (0.5-3), and Ri (1-100). The results showed that within the examined range of flow characteristics, the inlet Fr number is the most influential parameter in spherical tank thermocline formation and maintenance, and the largest tank thermal efficiency in a spherical tank is achieved at Fr = 0.5. Experimental results were obtained to validate the CFD model used in the parametric study. For the flow parameters within the current model, the use of an eddy viscosity turbulence model with variable turbulence intensity delivered the best agreement with experimental results. Overall, the experimental study using a spherical one tank setup validated the results of the CFD model with acceptable accuracy.

This thesis develops an analytical model of a small-scale solar central receiver power plant located at the California Polytechnic State University in San Luis Obispo, California at 35.28° N, 120.66° W. The model is used to analyze typical energy output at any time during the year. The power plant is designed to produce an output of 100 kW electrical power, and is supplemented by the combustion of natural gas. Methodologies for determining the proper size and layout of heliostats, optimal tower height, receiver size, and turbine engine selection are developed. In this specific design, solar shares of up to 73.2% and an annual average of 44% are possible through the use of a gas-solar hybrid microturbine engine. Larger solar shares are not possible due to the limited size of land (about 0.5 acres used for this project) which limits the number of possible heliostat installations.

This thesis presents a study on the design method to optimise the performance for producing green power from multiple renewable energy generators. The design method is presented through PLC (Programmable Logic Controller) theory. All the digital and analogue inputs are connected to the input cards. According to different operations conditions for each generator, the PLC will image all the inputs and outputs, from these images; a software program has been built to create a control method for multiple renewable energy generators to optimise production of green power. A control voltage will supply the output contractor from each generator via an interface relay. Three renewable generators (wind, solar, battery bank) have been used in the model system and the fourth generator is the back up diesel generator. The priority is for the wind generator due to availability of wind 24 hours a day, then solar, battery bank, and LPG or Diesel generators. Interlocking between the operations of the four contractors has been built to prevent interface between them. Change over between contractors, according to the generator's change over has also been built, so that it will delay supplying the main bus bar to prevent sudden supply to the load. Further study for controlling multiple renewable energy generators for different conditions such as controlling the multi-renewable energy generators from remote, or supplying weather forecast data from bureau of meteorology to the PLC directly as recommended. / Master of Electrical Engineering (Hons)

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The North House is a proof-of-concept prefabricated solar-powered home designed for northern climates, and intended for the research and promotion of high-performance sustainable architecture. Led by faculty at the University of Waterloo, the project was undertaken by Team North a broad collaboration between faculty and students at the Universities of Waterloo, Ryerson and Simon Fraser. In October 2009, the North House prototype competed in the U.S. Department of Energy’s Solar Decathlon, where it placed fourth overall. The North House addresses the urgent environmental imperative to dramatically reduce energy consumed by the built environment. It does so, in part by employing two primary technological systems which make use of feedback and response mechanisms; the Distributed Responsive System of Skins (DReSS) reconfigures the envelope in response to changing weather conditions, while the Adaptive Living Interface System (ALIS) provides detailed performance feedback to the inhabitant, equipping them with informed control of their home. This thesis recognizes energy consumption as a socio-technical problem that implicates building inhabitants as much as buildings themselves. It also recognizes the particular potency of the ‘house’ as a building type that touches a broad population in a profoundly personal way; and is thus an apt testing ground for technologies that conserve energy, and those that teach occupants to do the same. With these ideas in mind, the thesis looks to Interactive Architecture - a practice that considers buildings and their inhabitants as an integrated system - as a promising conceptual framework for synthesizing the social and technical aspects of energy conservation in the home.

The North House is a proof-of-concept prefabricated solar-powered home designed for northern climates, and intended for the research and promotion of high-performance sustainable architecture. Led by faculty at the University of Waterloo, the project was undertaken by Team North a broad collaboration between faculty and students at the Universities of Waterloo, Ryerson and Simon Fraser. In October 2009, the North House prototype competed in the U.S. Department of Energy’s Solar Decathlon, where it placed fourth overall. The North House addresses the urgent environmental imperative to dramatically reduce energy consumed by the built environment. It does so, in part by employing two primary technological systems which make use of feedback and response mechanisms; the Distributed Responsive System of Skins (DReSS) reconfigures the envelope in response to changing weather conditions, while the Adaptive Living Interface System (ALIS) provides detailed performance feedback to the inhabitant, equipping them with informed control of their home. This thesis recognizes energy consumption as a socio-technical problem that implicates building inhabitants as much as buildings themselves. It also recognizes the particular potency of the ‘house’ as a building type that touches a broad population in a profoundly personal way; and is thus an apt testing ground for technologies that conserve energy, and those that teach occupants to do the same. With these ideas in mind, the thesis looks to Interactive Architecture - a practice that considers buildings and their inhabitants as an integrated system - as a promising conceptual framework for synthesizing the social and technical aspects of energy conservation in the home.

The cost of grid based electrical and diesel sea water pumping to salt fields is one of the major cost components out of the total production cost in Puttalam Salt Limited, situated in northern part of Sri Lanka. In order to explore ways and means to improve the energy efficiency and alternative resources to meet the energy requirement a feasibility study was conducted using power system simulation software, (HOMER) and also detailed technical, environmental and financial tools.    This research study is conducted to evaluate the performances and applicability and propose the most suitable sustainable renewable energy source and methodology for water pumping to salt fields instead of currently utilized grid based and fossil fueled energy supply.   Preliminary results obtained by simulation software shows that direct wind mill pumping and solar PV water pumping was found to be unfeasible due to its limited pumping capacity and high investment cost. More over solar PV does not seems much feasible due to its high cost of energy (0.234 US $/kWh) compared to wind powered rivals in this type of applications.   Based on comparisons of the analysis it is seen that the wind/ grid combined configuration of 04 units of AOC15/50 model (50kW manufactured by AOC Renewable Energy - Canada) wind turbine units with 150kw inverter seems to be a logical supplement for water pumping energy requirement than using grid based electricity which costs 0.201 US $/ kWh. The solution in this research affords an attractive 60% annual average renewable fraction as well as an approximate 215.8 tCO2(eq) of annual Carbon Footprint saving. Also it assures a moderate Discounted Payback Period of 6 years and 5months with a 15% of Internal Rate of Return.

A background of concentrated solar power, and finite element analysis are provided, along with further technical details on the physics of parabolic light concentration and classical plate theory. The concept of optical efficiency is outlined, including the 5 contributing factors: the cosine effect, mirror reflectivity, blocking and shadowing, atmospheric attenuation, and surface irregularities. Surface irregularities are identified as the least predictable factor of optical efficiency, making them the subject of the experimental section. Physical and computational experimentation is conducted to determine a desirable selection for material of reflector substrate, thickness of reflector substrate, holding method of reflector, and aspect ratio of reflector. Physical and computational results are compared with one another to add validity to both sets of results. Recommendations are made for each design criteria selection, however it is found that in many cases the selection of reflector properties falls to an economic decision.

Solar heating systems, by the nature of their design and inherent thermal mass, are sensitive to the changes in the prevailing climatic conditions. A computer program has been developed to predict and display the dynamic performance of solar water heating systems and their installation designs under transient climatic and restricted site conditions. A multi-node capacitance model describes the dynamic heat transfer and energy storage processes within the solar collector unit, storage tank and the connecting pipework. This simulation model predicts the dynamic system performance under intermittent solar radiation, system operation and energy usage conditions. Validation studies have been carried out on the computer simulation results against the performance of a purpose-built solar collector test facility and a commercial solar water heating system in actual operation in Aberdeen. A good correlation has been obtained in both cases. The accuracy of the prediction was found to be dependant upon the time interval of the available climatic data and the complexity of the thermal simulation network chosen. The experimental facilities and the computer simulation program have been developed to investigate the effect of integrating the solar collector installation as part of the roof fabric, as a possible technique to improve the system performance in exposed locations. The application of this computer program lies in the development of innovative solar collector system and installation designs to achieve optimum system performance under transient climatic and restricted urban site conditions.

Low levels of energy access in sub-Saharan Africa and the acknowledgement of anthropogenic climate change have made sustainable energy products such as solar lanterns and efficient cookstoves a popular subject of international development programmes. At the same time, market-based approaches for distributing such ‘humanitarian goods’ have become increasingly prevalent. Based on ethnographic material from inside two development intermediaries, Global Village Energy Partnership (GVEP) International’s ‘Developing Energy Enterprises Project’ (DEEP) in Kenya and Uganda and SolarAid’s social enterprise ‘SunnyMoney’ in Malawi, this thesis argues that: 1) the complexity of applied market devices enhances inequalities between market actors; 2) the engendering of economic subjectivities within distribution chains can increase value-sharing; 3) there is space for both for-profit and non-profit ‘development’ intermediaries in marketisation processes, and; 4) further focus should be put on the promotion of domestic manufacturing. Stabilised market maps are used to present the activities of each organisation before turning to three frames of analysis that consider the problematisation, qualification and valuation of the energy products, the recruitment and training of supply chain ‘entrepreneurs’ and the specific market roles of development intermediaries, including provision of ‘brokerage’ services and as integral market actors. Bringing a theoretical vocabulary from economic sociology and science and technology studies into the arena of international development, the thesis reveals the extensive socio-technical configurations that constitute markets and create power asymmetries between actors. Without neglecting the vulnerabilities of the ‘bottom of the pyramid’ (BOP) as a ‘target group,’ it enhances our understanding of the shifts away from charity dependent beneficiaries’ towards ‘entrepreneurs,’ ‘customers’ and investment opportunities within sub-Saharan Africa.