No description available.

As South Africa's electricity consumption increases, Eskom is promoting Demand Side Management (DSM) to aid control of both the electricity consumption and its more effective usage, thereby delaying the need to construct new power stations, which pose large economic and environmental problems. Eskom has investigated various DSM strategies, such as load shifting, co-generation, alternative fuels and energy efficient processes, and has targeted the areas of load shifting and energy efficiency as prime areas for energy savings as they are relatively inexpensive and easy to implement. Pumps and fans form a large part of the industrial load. By improving the power usage of these devices with the use of variable speed drives, large energy savings may be achieved. To enable the energy usage of industrial loads to be evaluated, a test bed system which enables a variable speed drive to be loaded with a configurable load, was constructed. The test bed system forms a tool for evaluating and demonstrating the energy savings that are possible, by replacing fixed speed drives with variable speed drives when controlling the flow rate of pumps and fans. Results from the test bed system show that by using variable speed operation of pumps and fans, some energy savings are achievable when compared to existing methods of flow control. The achievable energy savings are dependent on the system properties and the duty cycle of the pump or fan system. / Thesis (M.Sc.)-University of Natal, Durban, 2001.

The addressed topic is to investigate the power distribution at a base metal refinery and to identify the potential improvement in power consumption efficiency. The work included in this study revealed that the power consumption efficiency at the evaluated base metal refinery can be improved. The significance of this study relates to Eskom’s tariff increases and directive to mining and large industrial companies to reduce their power consumption as well as the recent incremental increase in power tariffs. Base metal refineries are substantial power consumers and will be required to evaluate the efficiency of their base metal production. A load study was conducted at a base metal refinery in order to determine the current power consumption at the various process areas. The measurements obtained from the load study formed the basis for calculations to determine the potential efficiency improvement. The load study revealed that the electro-winning area contributes to the majority of the power consumed (52% of total apparent power) at the refinery. The potential improvement in efficiency at the electro-winning process area was identified by means of evaluating the rectifier and rectifier transformer power consumption. Methods and technologies for the reduction in power consumption was consequently evaluated and quantified. The potential reduction in conductor losses by converting from global power factor correction to localised power factor correction for the major plant areas was furthermore identified as an area of potential efficiency improvement and consequently evaluated. The improvement in motor efficiency across the base metal refinery was identified by means of comparing the efficiency and power factor of high efficiency motors to that of the standard efficiency motors installed at the refinery. The work included in this study reveals that an improvement in power consumption efficiency is achievable at the evaluated base metal refinery. An efficiency improvement of 1.785% (real power reduction of 2.07%) can be achieved by implementing localised power factor correction and high efficiency motors. An average efficiency improvement of 1.282% (total real power reduction of 2.78%) can be achieved with the additional implementation of specialised, high efficiency rectifier transformer designs. The implementation of localised power factor correction as well as high efficiency motors was identified as short term efficiency improvement projects. A financial study was conducted in order to determine the cost and payback period associated with the reduction in real power consumption for implementation of the recommended efficiency improvement projects. The payback period, required to achieve an average efficiency improvement of 1.785%, was calculated to be approximately 4 years. The initial capital investment required to implement the efficiency improvement projects is about R22.5 million. The monthly electricity utility bill savings associated with the efficiency improvement projects is approximately R455,000. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2012.

No abstract available. / Thesis (M.A.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.

In January 2008 the South African power grid operated by Eskom became severely constrained because electricity demand exceeded supply. Following the immediate measure of load shedding, Eskom implemented a medium term strategy of Power Conservation to encourage consumers to reduce their power usage so that overall demand could be managed. Despite the extensive campaigns the 10% electricity savings target was not met in 2008. The aim of this study was to review the experiences of other countries that had successfully implemented Power Conservation Programmes and to research the different approaches that were taken in other countries to encourage behaviour change. A survey and quantitative analysis was undertaken on a sample of electricity consumers within the eThekwini Municipality Central Region to gauge the response of consumers to the power conservation campaigns conducted within the municipality. The analysis was done to determine how the response had varied among the various groups by taking into account demographic factors like age, gender and income level. The population of the sample frame was estimated at 15 000 customers. Two hundred and eighty responses were received and analysed. A salient finding of the study was that the majority of respondents were aware of the reasons for power conservation and the campaigns undertaken, but that there was a preference for Government to lead the initiative and subsidise the required savings measures. A second important finding was that different demographic groups implemented different savings measures, for different reasons and preferred different strategies to encourage savings. The main recommendations made were that Government should lead the savings drive, with customised campaigns for different demographic groups. The campaigns should place greater emphasis on the financial benefits to be gained. It was necessary for new and different savings measures to be communicated. Further, the was a need for Government to introduce legislation to enforce electricity savings. / Thesis (MBA)-University of KwaZulu-Natal, Westville, 2009.

No description available.

Wireless access networks today consume 0.5 percent of the global energy. Rapidly growing demand for new services and ubiqutious connectivity, will further increase the energy consumption. This situation imposes a big challenge for mobile operators not only due to soaring cost of energy, but also increasing concern for global warming and sustainable development. This thesis focuses on the energy efficiency issue at the system level and studies how to incorporate energy-awareness into the design of future wireless access networks. The main contributions have been given in the areas of energy efficiency assessment, architectural and operational solutions, and total cost of investment analysis. The precise evaluation of energy efficiency is the first essential step to determine optimized solutions where metrics and models constitute the two key elements.We show that maximizing energy efficiency is not always equivalent to minimizing energy consumption which is one of the main reasons behind the presented contradictory and disputable conclusions in the literature. Further we indicate that in order to avoid the debatable directions, energy efficient network design problems should be formulated with well defined coverage and capacity requirements. Moreover, we propose novel backhaul power consumption models considering various technology and architectural options relevant for urban and rural environments and show that backhaul will potentially become a bottleneck in future ultra-high capacity wireless access networks. Second, we focus on clean-slate network deployment solutions satisfying different quality of service requirements in a more energy efficient manner. We identify that the ratio between idle- and transmit power dependent power consumption of a base station as well as the network capacity requirement are the two key parameters that affect the energy-optimum design.While results show that macro cellular systems are the most energy efficient solution for moderate average traffic density, Hetnet solutions prevail homogeneous deployment due to their ability to increase the capacity with a relatively lower energy consumption and thus enable significant energy savings in medium and high capacity demand regions. Moreover, we investigate the energy saving potential of short-term energy aware management approach, i.e., cell DTX, taking advantage of low resource utilization in the current networks arising from strict QoS requirements. With the help of developed novel quantitative method, we show that Cell DTX brings striking reduction in energy consumption and further savings are achievable if the networks are designed taking into account the fact that network deployment and operation are closely related. Finally, we develop a general framework for investigating the main cost elements and for evaluating the viability of energy efficient solutions.We first reveal the strong positive impact of spectrum on both energy and infrastructure cost and further indicate that applying sustainable solutions might also bring total cost reduction, but the viability highly depends on unit cost values as well as the indirect cost benefits of energy efficiency. Results obtained in this dissertation might provide guidelines for the network designers to achieve future high-capacity and sustainable wireless access networks. / <p>QC 20140505</p>

The total electricity consumption of plugged-in electric loads (PELs) currently accounts for more usage than any other single end-use service in residential and commercial buildings. Compared with other categories of electric loads, PELs possess significant potential to be efficiently controlled and managed in buildings. Therefore, accurate and reliable PEL identification methods that are used to collect identity and performance information are desired for many purposes. However, few existing electric load identification methods are designed for PELs to handle unique challenges such as the diversity within each type of PEL and similarity between different types of PELs equipped by similar front-end power supply units. The objective of this dissertation is to develop non-intrusive, accurate, robust, and applicable PEL identification algorithms utilizing voltage and current measurements. Based on the literature review of almost all existing features that describe electric loads and five types of existing methods for electric load identification, a two-level framework for PELs classification and identification is proposed. First, the supervised self-organizing map (SSOM) is adopted to classify a large number of PELs of different models and brands into several groups by their inherent similarities. Therefore, PELs with similar front-end power supply units or characteristics fall into the same group. The partitioned groups are verified by their power supply unit topology. That is, different groups should have different topologies. This dissertation proposes a novel combination of the SSOM framework and the Bayesian framework. Such a hybrid identifier can provide the probability of an unknown PEL belonging to a specific type of load. Within each classified group by the SSOM, both static and dynamic methods are proposed to distinguish PELs with similar characteristics. Static methods extract steady-state features from the voltage and current waveforms to train different computational intelligence algorithms such as the SSOM itself and the support vector machine (SVM). An unknown PEL is then presented to the trained algorithm for identification. In contrast to static methods, dynamic methods take into consideration the dynamics of long-term (minutes instead of milliseconds) waveforms of PELs and extract elements such as spikes, oscillations, steady-state operations, as well as similarly repeated patterns.

Wireless Sensor Networks (WSNs) are typically used to monitor specific phenomena and gather the data to a gateway node, where the data is further processed. WSNs nodes have limited power resources, which require developing power efficient systems. Additionally, reaching the nodes after a deployment to correct any design flaws is very challenging due the distributed nature of the nodes. The current development of WSNs occurs at the coding layer, which prevent the design from going through a typical software design process. Designing and analyzing the software modules of a WSN system at a higher abstraction layer than at the coding level will enable the designer of a WSN to fix any design errors and improve the system for power consumption at an early design stage, before the actual deployment of the network. This thesis presents multiple Unified Modeling Language (UML) design patterns that enable the designer to capture the structure and the behavior of the design of a WSN at higher abstraction layers. The UML models are developed based on these design patterns that are capable of early validation of the functional requirements and the power consumption of the system hardware resources by leveraging animation and instrumentation of the UML diagrams. To support the analysis of power consumption of the communication components of a WSN node, the Avrora network simulator was integrated with the UML design environment such that designer is able to analyze the power consumption analysis of the communication process at the UML layer. The UML and the Avrora simulation integration is achieved through developing a code generator that produces the necessary configuration for Avrora simulator and through parsing the simulator results. The methodology presented in this thesis is evaluated by demonstrating the power analysis of a typical collector system.

Water and electricity are fundamentally linked. Policy reforms in both industries, however, do not appear to acknowledge the links nor consider their wider implications. This is clearly unhelpful, particularly as policy makers attempt to develop effective responses to water and energy issues, underpinned by prevailing drought conditions and impending climate change. Against this backdrop, this research has comprehensively analysed the links between water and electricity – termed water-energy nexus – in the context of New South Wales. For this purpose, this research has developed an integrated methodological framework. The philosophical guidance for the development of this framework is provided by Integral Theory, and its analytical foundations rest on a suite of research methods including historical analysis, inputoutput analysis, analysis of price elasticities, and long-term scenario analysis. This research suggests that the historical and inextricable links between water and electricity, in the absence of integrated policies, has given rise to water-energy trade-offs. In the electricity industry, water-intensive coal-fired power stations that dominate base-load capacity in the National Electricity Market has resulted in intra- and inter-jurisdictional water sharing tradeoffs. Intermediate and peak demand technologies, suchas gas-fired, cogeneration and renewables, however, would significantly reduce the industry’s water consumption and carbon emissions. Drought and climate change adaptation responses in the water industry are likely to further increase electricity demand andpotentially contribute to climate change, due to policies that encourage investment in energy-intensive technologies, such as desalination, advanced wastewater treatment and rainwater tanks. Increasing electricity costs due to water shortages and the introduction of emissions trading will futher increase water and electricity prices for end users. Demand management strategies in both industries will assist in curbing price increases, however, their effectiveness is lessened by investment in water- and energy-intensive technologies in both industries. The analysis also demonstrates that strategies to reduce water and electricity consumption of ‘other’ production sectors in New South Wales is overwhelmingly dependent on how deeply a particular sector is embedded in the economy, in terms of its contribution to economic output, income generation and employment growth. Regulation, demand management programs, and water pricing policies, for example, that reduce the water and energy intensity of agriculture and key manufacturing sectors are likely to benefit the wider economy and the Environment. The future implications of the water-energy nexus are examined through long-term scenario analysis for New South Wales for 2031. The analysis demonstrates how policy decisions shape the domain for making philosophical choices by society - in terms of the balance between relying on alternative technologies and market arrangements, with differing implications for water and electricity use, and for instigating behavioural change. Based on these findings, this research puts forward a range of recommendations, essentially arguing for reorienting existing institutional arrangements, government measures and industry activities in a way that would encourage integration between the water and energy policies. Although the context of this research is New South Wales, the findings are equally relevant for other Australian states, which share the same national water and energy policy frameworks. Further, the concepts and frameworks developed in this research are also of value to other countries and regions that are faced with the task of designing appropriate policy responses to redress their water and energy challenges.