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

Eskom, the sole supplier of electricity in South Africa is facing an energy crisis. This is due to the steady increase in demand for electricity in South Africa. Low electricity prices in South Africa have helped the energy intensive industries of South Africa to be more competitive. Unfortunately this has resulted in poor energy efficiency practices and has hampered incentives to save energy. To address this problem, Eskom initiated a Demand Side Management (DSM) programme. DSM is beneficial to both Eskom and the client. However, due to the high cost of implementing such projects, it is feasible to implement it only on sites where the load shift potential is high enough for Eskom to benefit. The mining industry has been targeted for DSM programmes. This is due to the existence of a large mining sector in South Africa and to its energy intensive nature. Most mining operations require large amounts of water which is used to cool the underground environment and so ensure productivity and the safety of the workers. Due to the large amounts of water needed for mining, the electricity usage of these pumping systems is very high. If the use of this electricity can be optimised by implementing DSM principles, this will result in the long term savings of costs for the mines involved. The majority of pumping systems found on mines are single shaft systems. Individually these systems have a very high DSM potential. However, if multiple shaft systems can be used for DSM, the benefits will be far greater. Furthermore, combining several sites with an interconnected water pumping system will increase the potential for DSM and enable sites where individually the potential is too low to be feasible for a DSM project to raise their potential. This will result in more sites where DSM projects can be implemented and more clients who can benefit from the DSM programme. The purpose of this study is to investigate and implement a DSM project on an intricate multi-shaft mine pumping system which will be controlled from a single point. The project required a detailed investigation of the pumping systems on each shaft and how the water system is interlinked between the shafts. This project was carried out on Beatrix Mine Shafts 1, 2 and 3. The pumping systems were analysed and simulated according to the specific constraints and requirements that were specified by the mine. During the investigation and implementation of this project, possible efficiency improvements on certain pump stations were discovered and implemented. The improvements enabled both an increase in water flow to the surface and a decrease in power consumption. Due to this load reduction, the savings achieved were higher than those found in most load shifting projects. Moreover, additional infrastructures were installed to ensure communication between pumping systems. Once the simulation and optimisation of the control system was completed, the pumping system network was automated. The load shift resulted in a ± 3.5 MW shift in the morning peak demand period and a ± 6.0 MW shift in the evening peak demand period. This load shift has resulted in an average cost saving of R 80 000 per month during summer tariff period, and R 300 000 per month during winter tariff period. This saving result was calculated by taking load reduction into account. This project has shown that a DSM project can be implemented successfully, given the necessary historical data and expertise, on a pumping system that is interconnected between multiple shafts. / Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2007.

Eskom, the sole supplier of electricity in South Africa is facing an energy crisis. This is due to the steady increase in demand for electricity in South Africa. Low electricity prices in South Africa have helped the energy intensive industries of South Africa to be more competitive. Unfortunately this has resulted in poor energy efficiency practices and has hampered incentives to save energy. To address this problem, Eskom initiated a Demand Side Management (DSM) programme. DSM is beneficial to both Eskom and the client. However, due to the high cost of implementing such projects, it is feasible to implement it only on sites where the load shift potential is high enough for Eskom to benefit. The mining industry has been targeted for DSM programmes. This is due to the existence of a large mining sector in South Africa and to its energy intensive nature. Most mining operations require large amounts of water which is used to cool the underground environment and so ensure productivity and the safety of the workers. Due to the large amounts of water needed for mining, the electricity usage of these pumping systems is very high. If the use of this electricity can be optimised by implementing DSM principles, this will result in the long term savings of costs for the mines involved. The majority of pumping systems found on mines are single shaft systems. Individually these systems have a very high DSM potential. However, if multiple shaft systems can be used for DSM, the benefits will be far greater. Furthermore, combining several sites with an interconnected water pumping system will increase the potential for DSM and enable sites where individually the potential is too low to be feasible for a DSM project to raise their potential. This will result in more sites where DSM projects can be implemented and more clients who can benefit from the DSM programme. The purpose of this study is to investigate and implement a DSM project on an intricate multi-shaft mine pumping system which will be controlled from a single point. The project required a detailed investigation of the pumping systems on each shaft and how the water system is interlinked between the shafts. This project was carried out on Beatrix Mine Shafts 1, 2 and 3. The pumping systems were analysed and simulated according to the specific constraints and requirements that were specified by the mine. During the investigation and implementation of this project, possible efficiency improvements on certain pump stations were discovered and implemented. The improvements enabled both an increase in water flow to the surface and a decrease in power consumption. Due to this load reduction, the savings achieved were higher than those found in most load shifting projects. Moreover, additional infrastructures were installed to ensure communication between pumping systems. Once the simulation and optimisation of the control system was completed, the pumping system network was automated. The load shift resulted in a ± 3.5 MW shift in the morning peak demand period and a ± 6.0 MW shift in the evening peak demand period. This load shift has resulted in an average cost saving of R 80 000 per month during summer tariff period, and R 300 000 per month during winter tariff period. This saving result was calculated by taking load reduction into account. This project has shown that a DSM project can be implemented successfully, given the necessary historical data and expertise, on a pumping system that is interconnected between multiple shafts. / 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

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.