In this study a new tool was developed that made new approaches possible for the successful implementation of Demand Side Management (DSM) projects. The new approaches are incorporated into a generic tool that makes it possible for Energy Services Companies (ESCos) to undertake DSM projects that were previously not possible with currently available technology. Through these new approaches, maximum results can be obtained on a sustainable basis on the clear water pumping systems of South African mines. The author was responsible and participated in four different investigations and implementations of DSM projects. These were grouped into three case studies. Each of these studies required different new innovations. The innovations described in this thesis include the adaptation of the Real-time Energy Management System (REMS) that was developed and marketed by HVAC International, to mines with intricate pumping systems, mines without any instrumentation and control infrastructure, as well as to mines that make use of a Three Pipe Water Pumping System. The tool developed and applied in these projects was part of Eskom's DSM programme. In this programme, large electricity clients who wish to shift electrical load out of peak periods, are assisted by having the total costs of such projects funded by Eskom. The fact that the clients will most likely enjoy substantial electricity cost savings, (by not having to pay the high peak prices), is a major attraction of this programme. Nevertheless, the programme is not moving as fast as it should. The National Energy Regulator (NER) has set an annual target of 153 MW load to be shifted since 2003. By the end of 2005, the accumulated target load to be shifted will be 459 MW. However, Eskom has indicated that an accumulated total of only 181 MW load will have been shifted by the end of 2005. This means that the Eskom DSM programme has actually only achieved 39% of its target. The innovations described in this thesis will help ESCos to address this shortfall more effectively / Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2006

Thesis (M.Ing. (Electrical and Electronic Engineering))--North-West University, Potchefstroom Campus, 2007.

Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2006.

Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2007.

In this study a new tool was developed that made new approaches possible for the successful implementation of Demand Side Management (DSM) projects. The new approaches are incorporated into a generic tool that makes it possible for Energy Services Companies (ESCos) to undertake DSM projects that were previously not possible with currently available technology. Through these new approaches, maximum results can be obtained on a sustainable basis on the clear water pumping systems of South African mines. The author was responsible and participated in four different investigations and implementations of DSM projects. These were grouped into three case studies. Each of these studies required different new innovations. The innovations described in this thesis include the adaptation of the Real-time Energy Management System (REMS) that was developed and marketed by HVAC International, to mines with intricate pumping systems, mines without any instrumentation and control infrastructure, as well as to mines that make use of a Three Pipe Water Pumping System. The tool developed and applied in these projects was part of Eskom's DSM programme. In this programme, large electricity clients who wish to shift electrical load out of peak periods, are assisted by having the total costs of such projects funded by Eskom. The fact that the clients will most likely enjoy substantial electricity cost savings, (by not having to pay the high peak prices), is a major attraction of this programme. Nevertheless, the programme is not moving as fast as it should. The National Energy Regulator (NER) has set an annual target of 153 MW load to be shifted since 2003. By the end of 2005, the accumulated target load to be shifted will be 459 MW. However, Eskom has indicated that an accumulated total of only 181 MW load will have been shifted by the end of 2005. This means that the Eskom DSM programme has actually only achieved 39% of its target. The innovations described in this thesis will help ESCos to address this shortfall more effectively / Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2006

Eskom is currently facing an energy crisis due to the limited operational electricity generating capacity in South Africa. The historically low electricity price, the rapid growth in economy and the energy intensive nature of South African industries are the most common reasons for the peak supply problem. Various supply and demand technologies have been identified to address this energy crisis. Due to the lengthy process of building new peaking load power stations, Eskom has initiated the Demand-side Management (DSM) programme as a solution to the short-term supply problem. The National Energy Regulator (NER) has set targets to Eskom DSM to reduce the evening peak demand by 153 MW per annum and 4 255 MW over a 20-year planning horizon. Due to the energy intensive nature of the mining industry, it has been targeted for DSM savings. To date there have been a number of DSM projects implemented on the clear-water pumping systems of various mines, with a large potential for DSM savings identified on future projects still unrealised. The generation benefit of DSM load-shifting projects is twofold; firstly Eskom's evening load capacity increases due to the reduction in demand during these periods and secondly, the mine receives electricity cost savings due to load management practices. Because Eskom DSM is dependent on the client consumer to accept and roll-out the DSM programme, client satisfaction is of paramount importance. Due to the fact that load-shifting efforts require from the mine to change their normal operating schedules, there is uncertainty on the impact and knock-on effects of DSM projects on a mine. Therefore, the purpose of this study is to investigate and thereafter quantify the overall impact of DSM load-shifting on the clear-water pumping system of South African mines. A generic model was developed by performing case studies on existing DSM projects. This model was then applied to future DSM projects to validate the findings made throughout the research study. The case studies performed on existing DSM projects, as well as the results obtained when modelling the overall impact of DSM on future mines, proofs that DSM definitely benefits a mine. The total annual cost saving on the four future DSM projects is predicted to be in the order of R 7.64 million instead of the R 4.27 million when considering only the electricity cost savings to the mine. / Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2007.

Eskom is currently facing an energy crisis due to the limited operational electricity generating capacity in South Africa. The historically low electricity price, the rapid growth in economy and the energy intensive nature of South African industries are the most common reasons for the peak supply problem. Various supply and demand technologies have been identified to address this energy crisis. Due to the lengthy process of building new peaking load power stations, Eskom has initiated the Demand-side Management (DSM) programme as a solution to the short-term supply problem. The National Energy Regulator (NER) has set targets to Eskom DSM to reduce the evening peak demand by 153 MW per annum and 4 255 MW over a 20-year planning horizon. Due to the energy intensive nature of the mining industry, it has been targeted for DSM savings. To date there have been a number of DSM projects implemented on the clear-water pumping systems of various mines, with a large potential for DSM savings identified on future projects still unrealised. The generation benefit of DSM load-shifting projects is twofold; firstly Eskom's evening load capacity increases due to the reduction in demand during these periods and secondly, the mine receives electricity cost savings due to load management practices. Because Eskom DSM is dependent on the client consumer to accept and roll-out the DSM programme, client satisfaction is of paramount importance. Due to the fact that load-shifting efforts require from the mine to change their normal operating schedules, there is uncertainty on the impact and knock-on effects of DSM projects on a mine. Therefore, the purpose of this study is to investigate and thereafter quantify the overall impact of DSM load-shifting on the clear-water pumping system of South African mines. A generic model was developed by performing case studies on existing DSM projects. This model was then applied to future DSM projects to validate the findings made throughout the research study. The case studies performed on existing DSM projects, as well as the results obtained when modelling the overall impact of DSM on future mines, proofs that DSM definitely benefits a mine. The total annual cost saving on the four future DSM projects is predicted to be in the order of R 7.64 million instead of the R 4.27 million when considering only the electricity cost savings to the mine. / Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2007.

The South African Electricity Supply Industry is one of the backbone industries in South Africa. During 2003, it became clear that the demand for electricity in South Africa was increasing at a rate that had not been predicted nor recognised before. This was a clear indication that Eskom, the national electricity supply utility, would have to invest in additional generating capacity before 2007. Eskom envisioned these problems and introduced a DSM programme, which is aimed at reducing the national peak power demand. In so doing, the immediate need for additional power generating capacity will be postponed. A major part of this program is the concept of electrical load shifting. In 2000 mining in South Africa consumed 29% of the total quantity of electricity generated, of which the gold-mining industry consumed more than half. Electricity is the exclusive power source for the application of vital health and safety-related requirements in gold mines. In some cases, these consume in excess of 55% of the total electricity used on a mine. Water-pumping systems are a major part of these important applications. This dissertation presents a study of certain aspects of real-time energy management on old gold mines, by focusing on electrical load shifting on underground water pumping systems. Old gold mines use old, proven and energy-intensive methods that were not designed to conserve energy. This study also researches the challenges associated with the implementation of energy management strategies on old gold mines. Research was done on three old gold mines to determine the potential for load shifting on the underground water pumping systems of old gold mines. Integrated simulations were used as the main method of establishing this potential as well as the financial savings potential for the client. The simulation results showed large amounts of load-shifting potential for all three case studies and substantial financial savings potential for the clients. Real-time, load-shifting strategies were implemented on the three systems analysed in the case studies. The results generated by these strategies showed that load shifting could be realised on these systems, and confirmed the potential calculated in the simulations. Further research into the results however showed that the old infrastructure in the old mines caused many problems and influenced the sustainability of these strategies. From this study, the conclusions were made that; (a) there exists a potential for energy management on old gold mines, (b) there exists large potential for the implementation of sustainable energy management strategies on old gold mines, and (c) it is feasible to implement energy management strategies on old gold mines. / Thesis (M.Ing. (Electrical and Electronic Engineering))--North-West University, Potchefstroom Campus, 2007

An existing solar-powered water pumping system located in Mutomo, Kenya has beenevaluated in this paper. The requirement for this system is to produce a minimum of25m³ water per day throughout the year.The aim of this thesis is to investigate theperformance of the currently installed system and find a suitable replacement in termsof efficiency and economic viability. In order to acquire the necessary knowledge forthis project, a literature study was carried out to analyse the research within the area.Three simulation models were created which all include an electric motor driven by aphotovoltaic array and are connected to a submersible groundwater pump. Allmodels utilise space vector pulse width modulation. One model of an inductionmotor that represents the currently installed system, one induction motor thatdelivers a minimum of 25 m³ water per day, and one model of a permanent magnetsynchronous motor for comparison. Simulations using weather data, representing anaverage day for each month of the year were carried out. It was shown that thecurrently installed system does not fulfil the requirement of producing 25 m³ waterper day, and in addition produces a significant amount of energy that can not beutilised. It was also shown that the efficiency of the permanent magnet synchronousmotor was superior to the induction motors. In order to compare the systems interms of economic viability, price quotations from world leading manufacturers wereacquired. The results of the economic comparison show that the superior efficiencyof the permanent magnet synchronous motor was not enough to compensate for thehigher investment cost.

The South African Electricity Supply Industry is one of the backbone industries in South Africa. During 2003, it became clear that the demand for electricity in South Africa was increasing at a rate that had not been predicted nor recognised before. This was a clear indication that Eskom, the national electricity supply utility, would have to invest in additional generating capacity before 2007. Eskom envisioned these problems and introduced a DSM programme, which is aimed at reducing the national peak power demand. In so doing, the immediate need for additional power generating capacity will be postponed. A major part of this program is the concept of electrical load shifting. In 2000 mining in South Africa consumed 29% of the total quantity of electricity generated, of which the gold-mining industry consumed more than half. Electricity is the exclusive power source for the application of vital health and safety-related requirements in gold mines. In some cases, these consume in excess of 55% of the total electricity used on a mine. Water-pumping systems are a major part of these important applications. This dissertation presents a study of certain aspects of real-time energy management on old gold mines, by focusing on electrical load shifting on underground water pumping systems. Old gold mines use old, proven and energy-intensive methods that were not designed to conserve energy. This study also researches the challenges associated with the implementation of energy management strategies on old gold mines. Research was done on three old gold mines to determine the potential for load shifting on the underground water pumping systems of old gold mines. Integrated simulations were used as the main method of establishing this potential as well as the financial savings potential for the client. The simulation results showed large amounts of load-shifting potential for all three case studies and substantial financial savings potential for the clients. Real-time, load-shifting strategies were implemented on the three systems analysed in the case studies. The results generated by these strategies showed that load shifting could be realised on these systems, and confirmed the potential calculated in the simulations. Further research into the results however showed that the old infrastructure in the old mines caused many problems and influenced the sustainability of these strategies. From this study, the conclusions were made that; (a) there exists a potential for energy management on old gold mines, (b) there exists large potential for the implementation of sustainable energy management strategies on old gold mines, and (c) it is feasible to implement energy management strategies on old gold mines. / Thesis (M.Ing. (Electrical and Electronic Engineering))--North-West University, Potchefstroom Campus, 2007