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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Analysing the effect of DSM projects at South African cement factories / Johannes Paulus Spangenberg

Spangenberg, Johannes Paulus January 2015 (has links)
In any developing country an increasingly higher demand for electricity supply exists. South Africa experienced load shedding during late 2007 and early 2008 and again in 2014 due to a supply shortfall. New power stations are being built to increase the capacity of the national power grid. However this is a lengthy process. Demand Side Management (DSM) was adopted by Eskom’s Integrated Demand Management (IDM) division. DSM is a short-term solution to stabilise the national grid in South Africa by managing the electricity demand on the consumer’s or client’s side. DSM aims to reduce the electricity consumption with immediate results in the short-term. DSM projects were successfully implemented at nine South African cement factories since 2012. Cement factories are ideal for the implementation of DSM projects for the following reasons: cement factories are energy intensive; have adequate reserve production capacity; sufficient storage capacity and interruptible production schedules. The aim of this study is to analyse the effect of DSM projects at South African cement factories. A detailed understanding of the cement production process is a prerequisite. Therefore a critical review of energy utilisation in the cement industry was conducted. Previous work done in the cement production field is evaluated to identify the possible literature shortfall on DSM projects. A set of five distinctive parameters was derived from the literature survey to quantify the possible effects of DSM projects at cement factories. The parameters are demand reduction and electricity cost; production targets; infrastructure; product quality and sustainability. One cement factory, Factory #1, was selected as a primary case study for the analysis model. Factory #1 was used to determine and quantify the effects of DSM projects at cement factories. A simulation was developed to verify the analysis model outcome. DSM projects were implemented at various factories in South Africa and the results from nine sites were used to validate the aim of this study. The study concluded that most DSM projects at South African cement factories were sustainable. Both the electricity supplier and the factories benefitted from the projects. The funding received from Eskom to implement DSM projects is a short-term initiative. However, sustainability of DSM projects is made possible in the long-term by the substantial electricity cost savings on the client’s or factory’s side. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015
2

Analysing the effect of DSM projects at South African cement factories / Johannes Paulus Spangenberg

Spangenberg, Johannes Paulus January 2015 (has links)
In any developing country an increasingly higher demand for electricity supply exists. South Africa experienced load shedding during late 2007 and early 2008 and again in 2014 due to a supply shortfall. New power stations are being built to increase the capacity of the national power grid. However this is a lengthy process. Demand Side Management (DSM) was adopted by Eskom’s Integrated Demand Management (IDM) division. DSM is a short-term solution to stabilise the national grid in South Africa by managing the electricity demand on the consumer’s or client’s side. DSM aims to reduce the electricity consumption with immediate results in the short-term. DSM projects were successfully implemented at nine South African cement factories since 2012. Cement factories are ideal for the implementation of DSM projects for the following reasons: cement factories are energy intensive; have adequate reserve production capacity; sufficient storage capacity and interruptible production schedules. The aim of this study is to analyse the effect of DSM projects at South African cement factories. A detailed understanding of the cement production process is a prerequisite. Therefore a critical review of energy utilisation in the cement industry was conducted. Previous work done in the cement production field is evaluated to identify the possible literature shortfall on DSM projects. A set of five distinctive parameters was derived from the literature survey to quantify the possible effects of DSM projects at cement factories. The parameters are demand reduction and electricity cost; production targets; infrastructure; product quality and sustainability. One cement factory, Factory #1, was selected as a primary case study for the analysis model. Factory #1 was used to determine and quantify the effects of DSM projects at cement factories. A simulation was developed to verify the analysis model outcome. DSM projects were implemented at various factories in South Africa and the results from nine sites were used to validate the aim of this study. The study concluded that most DSM projects at South African cement factories were sustainable. Both the electricity supplier and the factories benefitted from the projects. The funding received from Eskom to implement DSM projects is a short-term initiative. However, sustainability of DSM projects is made possible in the long-term by the substantial electricity cost savings on the client’s or factory’s side. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015
3

A new approach to ensure successful implementation and sustainable DSM in RSA mines / Daniël Francois le Roux

Le Roux, Daniël Francois January 2005 (has links)
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
4

A new approach to ensure successful implementation and sustainable DSM in RSA mines / D.F. le Roux

Le Roux, Daniël Francois January 2005 (has links)
Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2006.
5

Researching the long-term impact of load management projects on South African mines / N.C.J.M. de Kock

De Kock, Nicolaas Cornelius Jacobus Marthinus January 2006 (has links)
Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2007.
6

A new approach to ensure successful implementation and sustainable DSM in RSA mines / Daniël Francois le Roux

Le Roux, Daniël Francois January 2005 (has links)
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
7

Researching the long-term impact of load management projects on South African mines / Nicolaas Cornelius Jacobus Marthinus de Kock

De Kock, Nicolaas Cornelius Jacobus Marthinus January 2006 (has links)
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.
8

Load shift through optimal control of complex underground rock winders /|cMzwandile Arthur Buthelezi

Buthelezi, Mzwandile Arthur January 2009 (has links)
South Africa's national power utility, Eskom, initiated a Demand Side Management (DSM) drive to help alleviate the electricity supply shortage experienced in South Africa. The focus of this study is on a load-shifting intervention applied in the mining environment. Load shifting is an appealing way of reducing peak demand. The mining sector is one of the largest consumers of electricity in South Africa. The application of DSM in this sector has the potential of yielding significant electrical load shifting. Firstly, this helps Eskom because they are struggling to keep up their supply. Secondly, the mines also benefit because electrical load is shifted to less expensive off-peak times. Electricity cost as a percentage of the total cost of mining output is bound to increase considerably the next few years. An investigation was conducted into the potential ofperforming load shifting on complex underground rock winders the mining sector. This involved a thorough study on existing load-shifting applications on rock winder systems. Simulations were performed on rock winder systems in their different configurations at deep-level gold mines. The simulation results indicated that there was potential for the application ofload shifting. Tau Tona was selected as a case study. This decision was based on simulations to establish which of the initially identified mines would be the best candidate for load shifting. Tau Tona has a complex underground rock winder system. Multiple rock winders feeding each other are used in a cascaded configuration. A potential load shifting target of 3' MW in the evening peak period was determined by means of simulation. The rock winder system was sequentially automated. An average evening peak demand load shift of 1 MW (or 4,2 MWh) was achieved. This translates to an average annual cost saving of R 240 000. If the load-shifting target of 3 MW could be obtained, the annual cost savings would increase by 30% to R 343 000. A study was also conducted on the feasibility of implementing maximum demand monitoring and control. Rock winders could be used in future to prevent the mines from exceeding their maximum demand. This is because rock winders consume very large amounts of electricity and can be stopped and restarted very quickly. Huge financial obligations can be prevented by making sure that the mines do not exceed their negotiated maximum demand. The necessary - and costly infrastructure to do this could not be procured during this study. / Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2010.
9

Researching the long-term impact of load management projects on South African mines / Nicolaas Cornelius Jacobus Marthinus de Kock

De Kock, Nicolaas Cornelius Jacobus Marthinus January 2006 (has links)
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.
10

Load shift through optimal control of complex underground rock winders /|cMzwandile Arthur Buthelezi

Buthelezi, Mzwandile Arthur January 2009 (has links)
South Africa's national power utility, Eskom, initiated a Demand Side Management (DSM) drive to help alleviate the electricity supply shortage experienced in South Africa. The focus of this study is on a load-shifting intervention applied in the mining environment. Load shifting is an appealing way of reducing peak demand. The mining sector is one of the largest consumers of electricity in South Africa. The application of DSM in this sector has the potential of yielding significant electrical load shifting. Firstly, this helps Eskom because they are struggling to keep up their supply. Secondly, the mines also benefit because electrical load is shifted to less expensive off-peak times. Electricity cost as a percentage of the total cost of mining output is bound to increase considerably the next few years. An investigation was conducted into the potential ofperforming load shifting on complex underground rock winders the mining sector. This involved a thorough study on existing load-shifting applications on rock winder systems. Simulations were performed on rock winder systems in their different configurations at deep-level gold mines. The simulation results indicated that there was potential for the application ofload shifting. Tau Tona was selected as a case study. This decision was based on simulations to establish which of the initially identified mines would be the best candidate for load shifting. Tau Tona has a complex underground rock winder system. Multiple rock winders feeding each other are used in a cascaded configuration. A potential load shifting target of 3' MW in the evening peak period was determined by means of simulation. The rock winder system was sequentially automated. An average evening peak demand load shift of 1 MW (or 4,2 MWh) was achieved. This translates to an average annual cost saving of R 240 000. If the load-shifting target of 3 MW could be obtained, the annual cost savings would increase by 30% to R 343 000. A study was also conducted on the feasibility of implementing maximum demand monitoring and control. Rock winders could be used in future to prevent the mines from exceeding their maximum demand. This is because rock winders consume very large amounts of electricity and can be stopped and restarted very quickly. Huge financial obligations can be prevented by making sure that the mines do not exceed their negotiated maximum demand. The necessary - and costly infrastructure to do this could not be procured during this study. / Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2010.

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