Growing demand for electricity forces suppliers to expand their generation capacity. Financing these expansion programmes results in electricity cost increases above inflation rates. By reducing electricity consumption, additional supply capacity is created at lower costs than the building of conventional power stations. Therefore, there is strong justification to reduce electricity consumption on the supplier and consumer side. The mining and industrial sectors of South Africa consumed approximately 43% of the total electricity supplied by Eskom during 2012. Approximately 10% of this electricity was used to produce compressed air. By reducing the electricity consumption of compressed air systems, operating costs are reduced. In turn this reduces the strain on the South African electricity network. Previous energy saving projects on mine compressed air systems realised savings that were not always sustainable. Savings deteriorated due to, amongst others, rapid employee turnover, improper training, lack of maintenance and system changes. There is therefore a need to improve projects that have already been implemented on mine compressed air systems. The continuous improvement of equipment (such as improved control valves) and the availability of newer technologies can be used to improve existing energy saving strategies. This study provides a solution to reduce the electricity consumption and operating costs of a deep level mine compressed air system. This was achieved by modernising and improving an existing underground compressed air saving strategy. This improvement resulted in a power saving of 1.15 MW; a saving equivalent to an annual cost saving of R4.16 million. It was found that the improved underground compressed air DSM project realised significant additional electrical energy savings. This resulted in ample cost savings to justify the implementation of the project improvements. It is recommended that opportunities to improve existing electrical energy saving projects on surface compressed air systems are investigated. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014

The demand for electricity in South Africa has grown faster than the increase in generation capacity. However, it is expensive and time consuming to commission new power stations. Another approach is to reduce electricity demand through the implementation of energy efficiency projects. This alternative is usually less expensive. Compressed air on South African mines is a large electricity consumer with a reputation of wastage. This allows significant potential for electrical and financial savings. A typical mine compressed air system consists of multiple compressors at various locations, surface connection networks, underground distribution systems, thousands of users and leaks. The size, complexity and age of these systems provide a major challenge for electricity saving efforts. Simulating such an intricate system is difficult as it is nearly impossible to accurately gather all the required system parameters. Some initiatives focused on subsections of mine compressed air systems. This is not the best approach as changes to one subsection may adversely affect other systems. A new approach to simplify mine compressed air systems was developed to identify saving opportunities and to assess the true impact of saving efforts. This new approach enables easier system analysis than complex simulation models. Techniques to gather critical system information are also provided. A new implementation procedure was also developed to integrate different energy saving strategies for maximum savings. An electrical power saving of 109 MW was achieved through the implementation of the integrated approach on twenty-two mine compressed air systems. The savings is equivalent to a reduction of 0.96 TWh per annum that relates to a saving of 0.4% of South Africa’s total electricity consumption. Average compressor power consumption was reduced by 30%. The power consumption reduction relates to an estimated annual electricity cost saving of R315 million. A saving of 0.96 TWh per annum is equivalent to a carbon dioxide emission reduction of 0.98 million tonne. The implementation of the integrated approach could be applied to other industrial compressed air systems. A reduction in electricity consumption of 30% on all industrial compressed air systems has the potential to reduce global electricity demand by 267 TWh per annum. That is more than the total amount of electricity consumed in South Africa. / Thesis (PhD (Electrical Engineering))--North-West University, Potchefstroom Campus, 2013

In 2011 South Africa's main electricity supplier, Eskom, experienced a peak electricity demand of 89% of their total installed generation capacity. The high utilisation rate makes it difficult to perform essential maintenance on the system. Eskom implements Demand-Side Management (DSM) projects in various industries, in order to reduce the demand and to ensure sustainable electricity supply. The mining sector consumes 14.5% of the total amount of electricity generated by Eskom. Mine compressed air systems can consume as much as 40% of a mine's total electricity requirements. This makes mine compressed air systems an ideal target for DSM. Electricity load seems to be reduced, but many DSM savings are not sustained throughout the project lifetime. An existing project feedback method of a specific Energy Services Company (ESCo) includes the manual collection of data from the mines and manual generation of reports. These reports show energy savings of the DSM projects to help the ESCo and their clients to improve and sustain the performance of the projects. A great amount of man-hours is used which results in large time delays in the feedback-loop. In order to address this, the need for a new automatic feedback reporting system was identified. This study mainly focusses on the development and implementation of a new method to monitor DSM savings on mine compressed air systems. It includes the reliable collection of data from mines, processing and storing of the data in a central database and generating savings reports. This is done automatically on a daily basis. In order to complete the feedback-loop, the reports are verified and emailed to clients and ESCo personnel on a daily basis. The new reporting system is implemented at a number of mines. Four of these project implementations are used as case studies to measure and interpret the effectiveness and value of this system. It saves a significant amount of man-hours and proves to be of great value in the sustainability of DSM project savings. Both Eskom and mining companies benefit from the efficient monitoring of mine compressed air savings. / Thesis (MIng (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2013.

Growing demand for electricity forces suppliers to expand their generation capacity. Financing these expansion programmes results in electricity cost increases above inflation rates. By reducing electricity consumption, additional supply capacity is created at lower costs than the building of conventional power stations. Therefore, there is strong justification to reduce electricity consumption on the supplier and consumer side. The mining and industrial sectors of South Africa consumed approximately 43% of the total electricity supplied by Eskom during 2012. Approximately 10% of this electricity was used to produce compressed air. By reducing the electricity consumption of compressed air systems, operating costs are reduced. In turn this reduces the strain on the South African electricity network. Previous energy saving projects on mine compressed air systems realised savings that were not always sustainable. Savings deteriorated due to, amongst others, rapid employee turnover, improper training, lack of maintenance and system changes. There is therefore a need to improve projects that have already been implemented on mine compressed air systems. The continuous improvement of equipment (such as improved control valves) and the availability of newer technologies can be used to improve existing energy saving strategies. This study provides a solution to reduce the electricity consumption and operating costs of a deep level mine compressed air system. This was achieved by modernising and improving an existing underground compressed air saving strategy. This improvement resulted in a power saving of 1.15 MW; a saving equivalent to an annual cost saving of R4.16 million. It was found that the improved underground compressed air DSM project realised significant additional electrical energy savings. This resulted in ample cost savings to justify the implementation of the project improvements. It is recommended that opportunities to improve existing electrical energy saving projects on surface compressed air systems are investigated. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014

The demand for electricity in South Africa has grown faster than the increase in generation capacity. However, it is expensive and time consuming to commission new power stations. Another approach is to reduce electricity demand through the implementation of energy efficiency projects. This alternative is usually less expensive. Compressed air on South African mines is a large electricity consumer with a reputation of wastage. This allows significant potential for electrical and financial savings. A typical mine compressed air system consists of multiple compressors at various locations, surface connection networks, underground distribution systems, thousands of users and leaks. The size, complexity and age of these systems provide a major challenge for electricity saving efforts. Simulating such an intricate system is difficult as it is nearly impossible to accurately gather all the required system parameters. Some initiatives focused on subsections of mine compressed air systems. This is not the best approach as changes to one subsection may adversely affect other systems. A new approach to simplify mine compressed air systems was developed to identify saving opportunities and to assess the true impact of saving efforts. This new approach enables easier system analysis than complex simulation models. Techniques to gather critical system information are also provided. A new implementation procedure was also developed to integrate different energy saving strategies for maximum savings. An electrical power saving of 109 MW was achieved through the implementation of the integrated approach on twenty-two mine compressed air systems. The savings is equivalent to a reduction of 0.96 TWh per annum that relates to a saving of 0.4% of South Africa’s total electricity consumption. Average compressor power consumption was reduced by 30%. The power consumption reduction relates to an estimated annual electricity cost saving of R315 million. A saving of 0.96 TWh per annum is equivalent to a carbon dioxide emission reduction of 0.98 million tonne. The implementation of the integrated approach could be applied to other industrial compressed air systems. A reduction in electricity consumption of 30% on all industrial compressed air systems has the potential to reduce global electricity demand by 267 TWh per annum. That is more than the total amount of electricity consumed in South Africa. / Thesis (PhD (Electrical Engineering))--North-West University, Potchefstroom Campus, 2013

In 2011 South Africa's main electricity supplier, Eskom, experienced a peak electricity demand of 89% of their total installed generation capacity. The high utilisation rate makes it difficult to perform essential maintenance on the system. Eskom implements Demand-Side Management (DSM) projects in various industries, in order to reduce the demand and to ensure sustainable electricity supply. The mining sector consumes 14.5% of the total amount of electricity generated by Eskom. Mine compressed air systems can consume as much as 40% of a mine's total electricity requirements. This makes mine compressed air systems an ideal target for DSM. Electricity load seems to be reduced, but many DSM savings are not sustained throughout the project lifetime. An existing project feedback method of a specific Energy Services Company (ESCo) includes the manual collection of data from the mines and manual generation of reports. These reports show energy savings of the DSM projects to help the ESCo and their clients to improve and sustain the performance of the projects. A great amount of man-hours is used which results in large time delays in the feedback-loop. In order to address this, the need for a new automatic feedback reporting system was identified. This study mainly focusses on the development and implementation of a new method to monitor DSM savings on mine compressed air systems. It includes the reliable collection of data from mines, processing and storing of the data in a central database and generating savings reports. This is done automatically on a daily basis. In order to complete the feedback-loop, the reports are verified and emailed to clients and ESCo personnel on a daily basis. The new reporting system is implemented at a number of mines. Four of these project implementations are used as case studies to measure and interpret the effectiveness and value of this system. It saves a significant amount of man-hours and proves to be of great value in the sustainability of DSM project savings. Both Eskom and mining companies benefit from the efficient monitoring of mine compressed air savings. / Thesis (MIng (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2013.

Electrical energy is commonly used in households and in industry - demand continues to rise due to economic and population growth. This requires that energy suppliers must increase their supply capacity. The result is that end–user energy costs continue to increase, therefore a growing need exists to reduce electrical energy demand in South Africa and internationally. Households account for the majority of electrical energy customers, but they only consume a fraction of the total energy supplied. The industrial sector and mines combined consume approximately 42% of the total electrical energy produced. Approximately 10% of this energy goes into compressed air production. This study focuses on methods of reducing the requirement of compressed air in industry so that the demand for electrical energy can be reduced. Many studies have focused on specific methods of reducing energy usage associated with compressed air production. These methods are categorised into methods of reducing compressed air requirements and methods of increasing compressed air supply efficiency. This study aims to combine these efforts into a single optimised solution. Although this study includes industry in general, the central focus is on the South African mining industry. Two different mining sites are considered and analysed as case studies. Methods of reducing energy required to produce compressed air were applied to each case study. Case Study 1 only allowed limited control of the compressed air system. In Case Study 2 integrated control was realised. Energy usage of compressors was reduced by 18.9% and 42.9% respectively. Results show that system savings can be doubled by combining different methods of reducing energy usage of compressed air. This, however, requires continuous monitoring and control of the air network at each section supplied with compressed air. The study is limited to achieving savings by changing the air system. Additional savings can be achieved by training personnel, altering schedules of production activities and implementing a system designed to locate air leaks. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2012.

Electrical energy is commonly used in households and in industry - demand continues to rise due to economic and population growth. This requires that energy suppliers must increase their supply capacity. The result is that end–user energy costs continue to increase, therefore a growing need exists to reduce electrical energy demand in South Africa and internationally. Households account for the majority of electrical energy customers, but they only consume a fraction of the total energy supplied. The industrial sector and mines combined consume approximately 42% of the total electrical energy produced. Approximately 10% of this energy goes into compressed air production. This study focuses on methods of reducing the requirement of compressed air in industry so that the demand for electrical energy can be reduced. Many studies have focused on specific methods of reducing energy usage associated with compressed air production. These methods are categorised into methods of reducing compressed air requirements and methods of increasing compressed air supply efficiency. This study aims to combine these efforts into a single optimised solution. Although this study includes industry in general, the central focus is on the South African mining industry. Two different mining sites are considered and analysed as case studies. Methods of reducing energy required to produce compressed air were applied to each case study. Case Study 1 only allowed limited control of the compressed air system. In Case Study 2 integrated control was realised. Energy usage of compressors was reduced by 18.9% and 42.9% respectively. Results show that system savings can be doubled by combining different methods of reducing energy usage of compressed air. This, however, requires continuous monitoring and control of the air network at each section supplied with compressed air. The study is limited to achieving savings by changing the air system. Additional savings can be achieved by training personnel, altering schedules of production activities and implementing a system designed to locate air leaks. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2012.