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Could renewable energy be implemented rapidly and on a large scale to supply the demand of stationary electrical grid systems? This thesis takes a step towards answering this question by simulating 100% renewable energy scenarios for the South-West Interconnected System (SWIS), which supplies electricity to most of the population and industry in the southwest of Western Australia (SWWA). The SWIS is remarkable in that it is both isolated from other grids and currently has little available hydro-power. Solar and wind energy were chosen as the energy sources to be simulated because they are commercially mature technologies, already have a presence in the SWIS, are widely available in many other parts of the world, yet they are geographically and temporally variable. To simulate the operation of rooftop solar PV and large scale solar and wind power plants, heuristic models were built to generate synthetic hourly values of solar and wind energy resources anywhere within the SWWA. An integrated simulation of the SWIS grid was built using simple models of population increase, energy efficiency, distributed battery storage and seasonal power to gas storage. The construction schedules required to build a 100% renewable system for the SWIS by the year 2030 were found to be achievable for scenarios with a mix of solar PV, solar thermal and wind. If solar PV, wind and battery storage capacity could maintain exponential growth, then the required growth rates are less than current global growth rates. Energy efficiency would need to improve at a greater rate, though still moderate, than the current global improvement rate. However, the more that energy efficiency is improved, the lower the total demand, and the easier the task becomes for the other technologies. The findings of this thesis have positive implications for world-wide rapid transformation to low emission electricity generation.

This thesis explores a recently developed concentrated solar thermal (CST) central receiver technology, known as the solid particle receiver (SPR). Calculations of long and near term thermo-economic competitiveness for promising potential applications were preformed, for the first time within the Australian context. With these results, the most suitable SPR technology configurations and technical developments, required to reach the commercial potential, were identified. An innovative simulation tool which included a variety of different thermodynamic and economic models, was developed to compute the annual performance of solar SPR systems. This simulation tool was then applied to design and to optimise CST SPR tower systems based on hourly simulations utilising meteorological data, the NREL Solar Position Algorithm, solar field efficiency matrices generated by DLR software HFLCAL, as well as a mathematical SPR model for calculating receiver efficiency. The SPR model was calibrated using results from DLR receiver prototype tests. To allow economic assessment of the entire SPR system, a financial model was implemented within the tool and detailed CST component costs were generated. The optimisation process utilised in the CST tower system design is more detailed than typical for a research project, since it adds a new degree of freedom when optimising the receiver and solar field. By decoupling the connection between solar field and receiver, the energy delivered from the solar field relative to the design receiver power becomes an additional optimisation variable. Applications of SPR systems for electricity production and industrial process heat generation have been identified for the Australian market. Promising heat supply uses of SPR technology examined in this thesis were: thermal enhanced oil recovery, preheating scrap metal during steel production, and solar augmentation of coal-fired steam power stations. Before this project, there were no detailed investigati

The present study focused on the development of transition metal oxide and metal nitride based thin film coatings to be utilized as a cost-effective solar selective surface that constitute a new approach in maximizing the power conversion efficiency. Despite many developments on transition metal oxide and metal nitride based selective solar absorbers, these materials are yet to be commercialized for solar thermal conversion applications. Numerous studies on CuCoO and graphene oxide based thin films are dedicated for their optical applications and light harvesting purposes. However to the best of our knowledge, utilization of mixed metal oxide/graphene oxide thin films as solar selective surface is yet to be explored. Both CuCoO and graphene oxide (GO) have generated significant research interest and have widespread applications in clean energy devices due to the good combinations of many important properties. Therefore, in this work we focus on the introduction of GO to the 3d transition metal-based CuCoO coatings and develop the new types optical thin films via dip-coating sol-gel technology to be used as solar selective surfaces. It is believed that use of graphene oxide in wet chemistry based sol-gel derived thin films will explore the new platform of producing highly efficient selective solar surfaces. Generally, 3d transition metal nitride based thin film coatings are studied for structural, mechanical, and electrical applications. However, a very limited number of investigations are directed in search of their optical and solar selective behaviors. With the increasing demand for clean energy alternatives, and economically viable energy devices our endeavor might bring some fruitful breakthroughs in development of 3d transition metal oxide and metal nitride based thin film coatings. Due to its flexibility and numerous technical advantages, the soft chemical sol-gel approach has been adopted to synthesize the metal oxides based thin film coatings. Unbalanced mag

Fuelled by a growing economy and increasing population, energy demand in the South West Interconnected System (SWIS) has risen by 10.04% in the past 5 years and is projected to rise by a possible 56% in the next 11 years (Independent Market Operator 2012). This dissertation focuses on the utilisation of renewable energy within the SWIS network in order to combat climate change. Summaries of renewable energy technologies (RETs) are provided and an analysis of resource availability given. Finally an examination of energy efficiency is undertaken to determine what its potential benefit to the SWIS network could be. A number of research projects and papers dedicated to the issue of integrating 100% renewable energy into national and/or local electrical grid networks were reviewed as part of this dissertation. The dissertation finds that there is ample renewable energy resource to power the SWIS for the foreseeable future. While a fully renewable energy based generation system will come at significant cost, it can be expected to bring with it decreased energy wastage. This is due to the removal of thermal baseload power stations that produce energy around the clock, including in periods of low demand. Moreover, a renewable energy, distributed generation system will better be able to match supply to demand. Finally, increased uptake of energy efficiency will have a major role to play in Western Australia’s future electricity generation mix as it will decrease the amount of additional generation capacity required.

The minority carrier lifetime distribution across silicon solar cells was investigated using variations of the open circuit voltage decay method. This was performed on monocrystalline, polycrystalline and amorphous silicon solar cells. Light from a white LED was focused using an aperture and a glass bi-convex lens to a spot size of 2mm on the surface of each cell investigated and moved in 1mm increments. At each point, a short pulse of light was emitted from the LED, with the open circuit voltage generated measured with time. This decay was then analysed using two calculation methods using a program written in LabVIEW. The generated minority carrier lifetime values at each point were exported in an array and plotted in Microsoft Excel, so that maps of the minority carrier lifetime were created. The calculation method from Mahan et al. (Mahan et al. 1979), produced values of the minority carrier lifetime that were consistently lower than the results found using the method from Ranjan, Solanki and Lal (Ranjan, Solanki, and Lal 2008). The values of the minority carrier lifetime obtained in both instances were generally in the expected range, once abnormally high lifetimes found to be a result of external factors (such as increased background effects due to low LED intensities or measured open circuit voltages) were removed. Due to the high levels of inaccuracy involved in analysis of the open circuit voltage decay curves, it was determined that this method could not produce reliable values of the minority carrier lifetime. However, through agreement of the two calculation methods used, the distribution of the minority carrier lifetime (such as regions of comparatively high and low lifetimes across a cell) could be determined with some accuracy in the case of the monocrystalline and polycrystalline silicon cells.