Influence of oxygen gas on the improvement of energy efficiency in induction furnace using foaming slag
- Kipepe Mwata, Theodore, Pan, Xiaowei
- Authors: Kipepe Mwata, Theodore , Pan, Xiaowei
- Date: 2015-05
- Subjects: Energy efficiency , Foaming slag , Induction furnace , Oxygen gas
- Type: Article
- Identifier: uj:5162 , ISSN 1021447x , http://hdl.handle.net/10210/14313
- Description: Since many years, the world has come together to face the challenge regarding the energy consumption and energy efficiency problems. In order to achieve and overcome these challenges, researchers have been focused on one of the most energy demanding sector worldwide which is the Industrial sectors and more specifically the Foundry. South Africa being one of the countries having the cheapest price of electricity and has brought a misusage of electricity and thus brought inefficiency in the industries and increase of prices in foundries. The purpose of this paper is to show the importance and impact of oxygen gas in the creation of a foaming slag during the melting process induction furnace (IF). Results have ! shown an optimum of oxygen gas injection of 100ml/sec and from 50 to 42 min which is a gain of almost 12 min in time (21% - 23.5%) and electrical energy consumption from 18.41kWh to 13.93kWh have been reduced to 2.56%. The thickness of slag foam increases from 0.2 - 0.9 cm during the experimental process and decreases the temperature on the surface of the foaming slag from 912°C to 878°C. As such, a simple heat transfer modelling and calculation have been conducted to see the impact and the relation between the heat loss and the foaming slag and result as shown that the heat saving was made from 9.1 - 9.2%.
- Full Text:
- Authors: Kipepe Mwata, Theodore , Pan, Xiaowei
- Date: 2015-05
- Subjects: Energy efficiency , Foaming slag , Induction furnace , Oxygen gas
- Type: Article
- Identifier: uj:5162 , ISSN 1021447x , http://hdl.handle.net/10210/14313
- Description: Since many years, the world has come together to face the challenge regarding the energy consumption and energy efficiency problems. In order to achieve and overcome these challenges, researchers have been focused on one of the most energy demanding sector worldwide which is the Industrial sectors and more specifically the Foundry. South Africa being one of the countries having the cheapest price of electricity and has brought a misusage of electricity and thus brought inefficiency in the industries and increase of prices in foundries. The purpose of this paper is to show the importance and impact of oxygen gas in the creation of a foaming slag during the melting process induction furnace (IF). Results have ! shown an optimum of oxygen gas injection of 100ml/sec and from 50 to 42 min which is a gain of almost 12 min in time (21% - 23.5%) and electrical energy consumption from 18.41kWh to 13.93kWh have been reduced to 2.56%. The thickness of slag foam increases from 0.2 - 0.9 cm during the experimental process and decreases the temperature on the surface of the foaming slag from 912°C to 878°C. As such, a simple heat transfer modelling and calculation have been conducted to see the impact and the relation between the heat loss and the foaming slag and result as shown that the heat saving was made from 9.1 - 9.2%.
- Full Text:
Energy efficiency enhancement of off-grid photovoltaic (PV) power plant
- Dlamini, Sibusiso B., Bakaya-Kyahurwa, Emmanuel, Mashinini, Peter M.
- Authors: Dlamini, Sibusiso B. , Bakaya-Kyahurwa, Emmanuel , Mashinini, Peter M.
- Date: 2017
- Subjects: Autonomous Photovoltaic (PV) , PV solar battery , Energy efficiency
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/244421 , uj:25273 , Citation: Dlamini, S.B., Bakaya-Kyahurwa, E. & Mashinini, P.M. 2017. Energy efficiency enhancement of off-grid photovoltaic (PV) power plant.
- Description: Abstract: The sizing of the off-grid PV systems is currently based on a manual approach, i.e. daily load is estimated by identifying commonly used load appliances for modelling system performance. If the system is not properly sized, it may not function according to expectation. The purpose of this paper is to present a conceptual design of an off-grid (autonomous) photovoltaic (PV) power plant, fitted with an efficient power regulating (EPR) management system of solar batteries and an instinctive solar tracking of PV panels. An optimization model for an Efficient Power Regulating (EPR) system of solar batteries was coupled to a solar tracking device so that the PV panels were constantly in full view of the sun. The objective function of the model was to maximize the efficiency of PV cells through PV battery charge regulation and load control in off-grid PV installations. This study revealed that the effectiveness of the EPR of solar battery (SB) when totally discharged can be realized when the accumulating battery (AB) charge reaches 50%.The study findings were indicative of the effectiveness of the EPR of SB. Hence, the EPR technique and the automatic tracking of PV solar panels proved to be the most effective technique of optimizing the energy efficiency of autonomous PV power plants.
- Full Text:
- Authors: Dlamini, Sibusiso B. , Bakaya-Kyahurwa, Emmanuel , Mashinini, Peter M.
- Date: 2017
- Subjects: Autonomous Photovoltaic (PV) , PV solar battery , Energy efficiency
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/244421 , uj:25273 , Citation: Dlamini, S.B., Bakaya-Kyahurwa, E. & Mashinini, P.M. 2017. Energy efficiency enhancement of off-grid photovoltaic (PV) power plant.
- Description: Abstract: The sizing of the off-grid PV systems is currently based on a manual approach, i.e. daily load is estimated by identifying commonly used load appliances for modelling system performance. If the system is not properly sized, it may not function according to expectation. The purpose of this paper is to present a conceptual design of an off-grid (autonomous) photovoltaic (PV) power plant, fitted with an efficient power regulating (EPR) management system of solar batteries and an instinctive solar tracking of PV panels. An optimization model for an Efficient Power Regulating (EPR) system of solar batteries was coupled to a solar tracking device so that the PV panels were constantly in full view of the sun. The objective function of the model was to maximize the efficiency of PV cells through PV battery charge regulation and load control in off-grid PV installations. This study revealed that the effectiveness of the EPR of solar battery (SB) when totally discharged can be realized when the accumulating battery (AB) charge reaches 50%.The study findings were indicative of the effectiveness of the EPR of SB. Hence, the EPR technique and the automatic tracking of PV solar panels proved to be the most effective technique of optimizing the energy efficiency of autonomous PV power plants.
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Utilising high and premium efficiency three phase motors with VFDs in a public water supply system
- Van Rhyn, P., Pretorius, J.H.C.
- Authors: Van Rhyn, P. , Pretorius, J.H.C.
- Date: 2015-05-13
- Subjects: Centrifugal pump systems , Energy efficiency , Variable frequency drives
- Type: Article
- Identifier: uj:5107 , ISBN 978-1-4799-9978-1 , http://hdl.handle.net/10210/13929
- Description: The increased reliability and ultimately reduced life cycle cost of high and premium efficiency three phase motors in a process control application is discussed. The reduced energy consumption of these motors is evaluated in a public water system case study under variable frequency conditions. The importance of the consideration of a combined system, which includes variable speed control, motor and load - as opposed to only replacing with high efficiency motors for energy saving purposes - is practically observed and reported on. The paper reports on the marginal improvement in energy consumption at reduced supply frequency for motor replacement only (not surprising) but a very impressive 46% saving in energy consumption by controlling pumped water at a reduced but constant delivery rate.
- Full Text:
- Authors: Van Rhyn, P. , Pretorius, J.H.C.
- Date: 2015-05-13
- Subjects: Centrifugal pump systems , Energy efficiency , Variable frequency drives
- Type: Article
- Identifier: uj:5107 , ISBN 978-1-4799-9978-1 , http://hdl.handle.net/10210/13929
- Description: The increased reliability and ultimately reduced life cycle cost of high and premium efficiency three phase motors in a process control application is discussed. The reduced energy consumption of these motors is evaluated in a public water system case study under variable frequency conditions. The importance of the consideration of a combined system, which includes variable speed control, motor and load - as opposed to only replacing with high efficiency motors for energy saving purposes - is practically observed and reported on. The paper reports on the marginal improvement in energy consumption at reduced supply frequency for motor replacement only (not surprising) but a very impressive 46% saving in energy consumption by controlling pumped water at a reduced but constant delivery rate.
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Negative energy impacts in the absence of proper baseline studies - a South African case study
- Pretorius, J.H.C., Van Rhyn, P., De Canha, D.
- Authors: Pretorius, J.H.C. , Van Rhyn, P. , De Canha, D.
- Date: 2016
- Subjects: Measurement and verification , Energy efficiency , Underground ventilation
- Language: English
- Type: Conference proceedings
- Identifier: http://ujcontent.uj.ac.za8080/10210/368139 , http://hdl.handle.net/10210/213583 , uj:21171 , Citation: Pretorius, J.H.C., Van Rhyn, P & De Canha, D. 2016. Negative energy impacts in the absence of proper baseline studies - a South African case study.
- Description: Abstract: Energy Conservation projects have become a focus area throughout the world in an attempt to reduce greenhouse gasses. These projects encompass various energy efficient technologies of which the retrofit of old technologies with new technology has become a common phenomenon. Energy savings are usually quantified by comparing actual post-retrofit energy consumption levels with baseline levels representative of the preretrofit status quo, adjusted for changes in energy drivers (e.g. weather). Baseline adjustments during energy conservation projects are of the utmost importance if operating conditions, occupancies, ambient temperatures, production levels and other factors have changed between the baseline period and the postretrofit period. During a recent case study in South Africa, an HVAC retrofit was done on a multistorey building where old technology air-conditioners were replaced with heat pump based units with inverters. To the disappointment of the landlord, the post energy measurements exceeded the baseline energy consumption by approximately 12% without any changes in operating conditions. This paper illustrates the catastrophic effects when an energy efficiency project is accelerated to the implementation stage without due consideration of operating conditions during the pre-implementation stage. A qualitative analysis prior to baseline establishment is proposed.
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- Authors: Pretorius, J.H.C. , Van Rhyn, P. , De Canha, D.
- Date: 2016
- Subjects: Measurement and verification , Energy efficiency , Underground ventilation
- Language: English
- Type: Conference proceedings
- Identifier: http://ujcontent.uj.ac.za8080/10210/368139 , http://hdl.handle.net/10210/213583 , uj:21171 , Citation: Pretorius, J.H.C., Van Rhyn, P & De Canha, D. 2016. Negative energy impacts in the absence of proper baseline studies - a South African case study.
- Description: Abstract: Energy Conservation projects have become a focus area throughout the world in an attempt to reduce greenhouse gasses. These projects encompass various energy efficient technologies of which the retrofit of old technologies with new technology has become a common phenomenon. Energy savings are usually quantified by comparing actual post-retrofit energy consumption levels with baseline levels representative of the preretrofit status quo, adjusted for changes in energy drivers (e.g. weather). Baseline adjustments during energy conservation projects are of the utmost importance if operating conditions, occupancies, ambient temperatures, production levels and other factors have changed between the baseline period and the postretrofit period. During a recent case study in South Africa, an HVAC retrofit was done on a multistorey building where old technology air-conditioners were replaced with heat pump based units with inverters. To the disappointment of the landlord, the post energy measurements exceeded the baseline energy consumption by approximately 12% without any changes in operating conditions. This paper illustrates the catastrophic effects when an energy efficiency project is accelerated to the implementation stage without due consideration of operating conditions during the pre-implementation stage. A qualitative analysis prior to baseline establishment is proposed.
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Increased energy efficiency of a steel foundry plant by using a cleaner production Quick-E-Scan methodology
- Rasmenia, Zelda, Pan, Xiaowei
- Authors: Rasmenia, Zelda , Pan, Xiaowei
- Date: 2017
- Subjects: Energy efficiency , Energy assessment , Quick-E-scan methodology
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/239156 , uj:24566 , Citation: Rasmenia, Z. & Pan, X. 2017. Increased energy efficiency of a steel foundry plant by using a cleaner production Quick-E-Scan methodology.
- Description: Abstract: The Quick-E-Scan methodology is a simple and quick method that is used to achieve operational energy efficiency as opposed to detailed energy audits, which therefore offers a no cost or less cost solutions for energy management programs with a limited budget. The quick-E-scan methodology was used to assesses a steel foundry plant based in Benoni through dividing the foundry into production sections which entailed a review of the current processes and usage patterns of energy within the plant and a detailed analysis of options available for improvement and profitable areas in which energy saving measures may be implemented for an increase energy efficiency which can be presented to management of the company.
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- Authors: Rasmenia, Zelda , Pan, Xiaowei
- Date: 2017
- Subjects: Energy efficiency , Energy assessment , Quick-E-scan methodology
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/239156 , uj:24566 , Citation: Rasmenia, Z. & Pan, X. 2017. Increased energy efficiency of a steel foundry plant by using a cleaner production Quick-E-Scan methodology.
- Description: Abstract: The Quick-E-Scan methodology is a simple and quick method that is used to achieve operational energy efficiency as opposed to detailed energy audits, which therefore offers a no cost or less cost solutions for energy management programs with a limited budget. The quick-E-scan methodology was used to assesses a steel foundry plant based in Benoni through dividing the foundry into production sections which entailed a review of the current processes and usage patterns of energy within the plant and a detailed analysis of options available for improvement and profitable areas in which energy saving measures may be implemented for an increase energy efficiency which can be presented to management of the company.
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Evaluation of savings from an underground fan replacement project
- De Canha, D., Pretorius, J.H.C., Laubscher, R., Van Rhyn, P.
- Authors: De Canha, D. , Pretorius, J.H.C. , Laubscher, R. , Van Rhyn, P.
- Date: 2016
- Subjects: Measurement and verification , Energy efficiency , Underground ventilation
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/213676 , uj:21182 , De Canha, D. et al. 2016. Evaluation of savings from an underground fan replacement project.
- Description: Abstract: The savings calculation methodology from a fan replacement project is presented in this paper. The fans replaced are part of the underground ventilation system in a platinum mine. Initially, 290 axial flow fans rated at 45kW were to be replaced with carbon fibre composite fans. According to the manufacturer, the carbon fibre construction allowed for an optimum blade shape which results in the carbon fibre fan being more energy efficient. However, after the first few fans were replaced, it was discovered that the mine’s blasting activities caused the carbon fibre fans to crack and eventually fail. Fortunately, the manufacturer was able to produce a steel fan with similar performance to that of the carbon composite fans and continue replacing old fans in the mine. The savings were independently verified according to the International Performance Measurement & Verification Protocol (IPMVP). This involved testing old and new fans in a BS848 test duct and comparing the old and new fans at various operating points on their fan curves and making adjustments for operating conditions such as air density underground vs at the test duct. It was found that the new fans saved 5kW on average, across a range of operating points.
- Full Text:
- Authors: De Canha, D. , Pretorius, J.H.C. , Laubscher, R. , Van Rhyn, P.
- Date: 2016
- Subjects: Measurement and verification , Energy efficiency , Underground ventilation
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/213676 , uj:21182 , De Canha, D. et al. 2016. Evaluation of savings from an underground fan replacement project.
- Description: Abstract: The savings calculation methodology from a fan replacement project is presented in this paper. The fans replaced are part of the underground ventilation system in a platinum mine. Initially, 290 axial flow fans rated at 45kW were to be replaced with carbon fibre composite fans. According to the manufacturer, the carbon fibre construction allowed for an optimum blade shape which results in the carbon fibre fan being more energy efficient. However, after the first few fans were replaced, it was discovered that the mine’s blasting activities caused the carbon fibre fans to crack and eventually fail. Fortunately, the manufacturer was able to produce a steel fan with similar performance to that of the carbon composite fans and continue replacing old fans in the mine. The savings were independently verified according to the International Performance Measurement & Verification Protocol (IPMVP). This involved testing old and new fans in a BS848 test duct and comparing the old and new fans at various operating points on their fan curves and making adjustments for operating conditions such as air density underground vs at the test duct. It was found that the new fans saved 5kW on average, across a range of operating points.
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Optimization of the compressed air-usage in South African mines
- Hassan, Ali, Ouahada, Khmaies, Marwala, Tshilidzi, Twala, Bhekisipho
- Authors: Hassan, Ali , Ouahada, Khmaies , Marwala, Tshilidzi , Twala, Bhekisipho
- Date: 2011
- Subjects: Demand side management , Energy efficiency , Mines , Compressed air
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/16393 , uj:15768 , Citation: Hassan, A. et al. 2011. Optimization of the compressed air-usage in South African mines. IEEE Africon, 13-15 September, 2011, Zambia.
- Description: Abstract: The critical electricity supply in South Africa has necessitated the implementation of demand-side management (DSM) projects. Load shifting and energy efficiency projects were introduced on mining sectors to reduce the electricity usage during day peak time...
- Full Text:
- Authors: Hassan, Ali , Ouahada, Khmaies , Marwala, Tshilidzi , Twala, Bhekisipho
- Date: 2011
- Subjects: Demand side management , Energy efficiency , Mines , Compressed air
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/16393 , uj:15768 , Citation: Hassan, A. et al. 2011. Optimization of the compressed air-usage in South African mines. IEEE Africon, 13-15 September, 2011, Zambia.
- Description: Abstract: The critical electricity supply in South Africa has necessitated the implementation of demand-side management (DSM) projects. Load shifting and energy efficiency projects were introduced on mining sectors to reduce the electricity usage during day peak time...
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Smart homes : a domestic demand response and demand side energy management system for future smart grids
- Hoosain, Mohamed Sameer, Paul, Babu Sena
- Authors: Hoosain, Mohamed Sameer , Paul, Babu Sena
- Date: 2017
- Subjects: Demand side management (DSM) , Demand response (DR) , Energy efficiency
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/225478 , uj:22774 , Citation: Hoosain, M.S. & Paul, B.S. 2017. Smart homes : a domestic demand response and demand side energy management system for future smart grids.
- Description: Abstract: Smart homes or the homes of the future will be equipped with advanced technologies for user comfort and entertainment. Intelligent systems will be available to ensure this comfort and reliability. With these technological advancements comes further energy management. The concept of domestic energy efficiency is a concern at present and will be, in the future. So how do we optimize homes and users as to how they conserve energy? Domestic user’s energy usage represents a large amount of total electricity demand. Typical home energy systems utilize a rudimentary form of energy efficiency and management. In this paper we look at a Demand Response and Demand side management system model to curb this situation. The demand response system is achieved by the utility turning on/off smart power plugs wirelessly throughout the home based on peak and off peak periods via communication through its smart grid. To help consumers shift their loads during these times, appliance power sources that can act autonomously based on wired or wireless signals received from the utility via its smart grid is required. Users in response to this, connect their appliances to these plugs by generating their own hierarchy system by prioritizing their appliance usage. Whereas the demand side management system allows users to manually configure dates and times for the turning on/off of the smart power plugs wirelessly through the user’s smart user interface. Therefore, an energy efficient future smart home that can save the user on monthly expenditure and save on energy simultaneously.
- Full Text:
- Authors: Hoosain, Mohamed Sameer , Paul, Babu Sena
- Date: 2017
- Subjects: Demand side management (DSM) , Demand response (DR) , Energy efficiency
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/225478 , uj:22774 , Citation: Hoosain, M.S. & Paul, B.S. 2017. Smart homes : a domestic demand response and demand side energy management system for future smart grids.
- Description: Abstract: Smart homes or the homes of the future will be equipped with advanced technologies for user comfort and entertainment. Intelligent systems will be available to ensure this comfort and reliability. With these technological advancements comes further energy management. The concept of domestic energy efficiency is a concern at present and will be, in the future. So how do we optimize homes and users as to how they conserve energy? Domestic user’s energy usage represents a large amount of total electricity demand. Typical home energy systems utilize a rudimentary form of energy efficiency and management. In this paper we look at a Demand Response and Demand side management system model to curb this situation. The demand response system is achieved by the utility turning on/off smart power plugs wirelessly throughout the home based on peak and off peak periods via communication through its smart grid. To help consumers shift their loads during these times, appliance power sources that can act autonomously based on wired or wireless signals received from the utility via its smart grid is required. Users in response to this, connect their appliances to these plugs by generating their own hierarchy system by prioritizing their appliance usage. Whereas the demand side management system allows users to manually configure dates and times for the turning on/off of the smart power plugs wirelessly through the user’s smart user interface. Therefore, an energy efficient future smart home that can save the user on monthly expenditure and save on energy simultaneously.
- Full Text:
The effectiveness of solar water heating geysers in South Africa : a review
- Thobejane, Jackson S., Masekameni, Daniel M., Rathebe, Phoka C., Mgwambani, Shalala L.
- Authors: Thobejane, Jackson S. , Masekameni, Daniel M. , Rathebe, Phoka C. , Mgwambani, Shalala L.
- Date: 2019
- Subjects: Solar water heating geysers , Renewable energy , Energy efficiency
- Language: English
- Type: Conference proceeding
- Identifier: http://hdl.handle.net/10210/395692 , uj:32824 , Citation: Thobejane, J.S. et al. 2019. The effectiveness of solar water heating geysers in South Africa : a review.
- Description: Abstract: The heating of water for domestic purposes is an important component of human daily activities, especially during cold weather conditions. In South Africa, it is estimated that households spend an average of 40% of their electricity on domestic water heating alone. This alone threatens energy affordability and access due to the high cost of electricity. The South African government seeing that the majority of low-income households do not afford electricity, introduced solar water heating (SWH) geysers as a possible affordable energy alternative technology. The massive roll-out of the solar water geysers began in 2008 managed to install 443 486 SWH geysers. This desktop study is envisaged to evaluate the implementation of the strategy and ends by investigating the effectiveness of the SWH geysers on reducing household grid energy demand between 2009 and 2017. The results of this study will illustrate the effectiveness, failures, successes or future approaches evolving around this technology.
- Full Text:
- Authors: Thobejane, Jackson S. , Masekameni, Daniel M. , Rathebe, Phoka C. , Mgwambani, Shalala L.
- Date: 2019
- Subjects: Solar water heating geysers , Renewable energy , Energy efficiency
- Language: English
- Type: Conference proceeding
- Identifier: http://hdl.handle.net/10210/395692 , uj:32824 , Citation: Thobejane, J.S. et al. 2019. The effectiveness of solar water heating geysers in South Africa : a review.
- Description: Abstract: The heating of water for domestic purposes is an important component of human daily activities, especially during cold weather conditions. In South Africa, it is estimated that households spend an average of 40% of their electricity on domestic water heating alone. This alone threatens energy affordability and access due to the high cost of electricity. The South African government seeing that the majority of low-income households do not afford electricity, introduced solar water heating (SWH) geysers as a possible affordable energy alternative technology. The massive roll-out of the solar water geysers began in 2008 managed to install 443 486 SWH geysers. This desktop study is envisaged to evaluate the implementation of the strategy and ends by investigating the effectiveness of the SWH geysers on reducing household grid energy demand between 2009 and 2017. The results of this study will illustrate the effectiveness, failures, successes or future approaches evolving around this technology.
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Public participation in technological innovation : the case of the Tshulu stove development programme
- Makonese, Tafadzwa, Bradnum, Christopher M. S.
- Authors: Makonese, Tafadzwa , Bradnum, Christopher M. S.
- Date: 2017
- Subjects: Co-design , Energy efficiency , Improved cookstove
- Language: English
- Type: Articles
- Identifier: http://hdl.handle.net/10210/241293 , uj:24838 , Citation: Makonese, T. & Bradnum, C.M.S. 2017. Public participation in technological innovation : the case of the Tshulu stove development programme. Journal of Energy in Southern Africa 28(1): 13–24 DOI: http://dx.doi.org/10.17159/2413-3051/2017/v28i1a1379 , ISSN: 2413-3051
- Description: Abstract: The design of products for developing communities often excludes the end-users in the decision making process. The study aims to investigate public participation and engagement in the design and development of the Tshulu woodstove. Results of this research point to the need for improved communication between citizens and technical experts, as well as for narrowing the gap between the designer and the user by encouraging meaningful engagement and inclusion. Bottom-up approaches ensure sustained participation of the public, in turn increasing a sense of ownership in the product. These results have implications for energy policy and improved cookstove programmes for developing communities.
- Full Text:
- Authors: Makonese, Tafadzwa , Bradnum, Christopher M. S.
- Date: 2017
- Subjects: Co-design , Energy efficiency , Improved cookstove
- Language: English
- Type: Articles
- Identifier: http://hdl.handle.net/10210/241293 , uj:24838 , Citation: Makonese, T. & Bradnum, C.M.S. 2017. Public participation in technological innovation : the case of the Tshulu stove development programme. Journal of Energy in Southern Africa 28(1): 13–24 DOI: http://dx.doi.org/10.17159/2413-3051/2017/v28i1a1379 , ISSN: 2413-3051
- Description: Abstract: The design of products for developing communities often excludes the end-users in the decision making process. The study aims to investigate public participation and engagement in the design and development of the Tshulu woodstove. Results of this research point to the need for improved communication between citizens and technical experts, as well as for narrowing the gap between the designer and the user by encouraging meaningful engagement and inclusion. Bottom-up approaches ensure sustained participation of the public, in turn increasing a sense of ownership in the product. These results have implications for energy policy and improved cookstove programmes for developing communities.
- Full Text:
Energy efficiency through the use of technology in South African industry
- Matlala, H.N., Marnewick, A., Pretorius, J.H.C.
- Authors: Matlala, H.N. , Marnewick, A. , Pretorius, J.H.C.
- Date: 2016
- Subjects: Energy demand , Energy management , Energy efficiency
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/213535 , uj:21163 , Citation: Matlala, H.N., Marnewick, A & Pretorius, J.H.C. 2016. Energy efficiency through the use of technology in South African industry.
- Description: Abstract: South Africa’s increasing cost of industrial energy has recently caused the country to be ranked among the top five countries in the world with the most expensive industrial electricity tariffs. For various reasons, energy is often not optimally used in industry. According to Zavanella and Zanoni (2009), there has been a growing interest in more rational and responsible consumption of energy, especially in industrial processes and services. This research study demonstrates the use of technology for energy efficiency in the industry, in order to reduce energy consumed per unit produced on industrial process plants.
- Full Text:
- Authors: Matlala, H.N. , Marnewick, A. , Pretorius, J.H.C.
- Date: 2016
- Subjects: Energy demand , Energy management , Energy efficiency
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/213535 , uj:21163 , Citation: Matlala, H.N., Marnewick, A & Pretorius, J.H.C. 2016. Energy efficiency through the use of technology in South African industry.
- Description: Abstract: South Africa’s increasing cost of industrial energy has recently caused the country to be ranked among the top five countries in the world with the most expensive industrial electricity tariffs. For various reasons, energy is often not optimally used in industry. According to Zavanella and Zanoni (2009), there has been a growing interest in more rational and responsible consumption of energy, especially in industrial processes and services. This research study demonstrates the use of technology for energy efficiency in the industry, in order to reduce energy consumed per unit produced on industrial process plants.
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Design of energy efficient hybrid VLC/RF/PLC communication system for indoor networks
- Aboagye, Sylvester, Ibrahim, Ahmed, Ngatched, Telex M. N., Ndjiongue, Alain R., Dobre, Octavia A.
- Authors: Aboagye, Sylvester , Ibrahim, Ahmed , Ngatched, Telex M. N. , Ndjiongue, Alain R. , Dobre, Octavia A.
- Date: 2019
- Subjects: Energy efficiency , Visible light communication , Power line communication
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/399299 , uj:33275 , Citation: Aboagye, S. et al. 2019. Design of energy efficient hybrid VLC/RF/PLC communication system for indoor networks.
- Description: Abstract: Integrating visible light communication (VLC) system with indoor radio frequency (RF) network is seen as a possible way of increasing the capacity and coverage of indoor networks. In such a hybrid network, the traffic generated at the indoor RF and VLC access points must be backhauled to the core network. Power line communication (PLC) technology is seen as a cost-effective backhaul (BH) solution due to its infrastructure availability in every home. In this letter, a novel system model that captures the joint effect of power and BH flow optimization for hybrid VLC/RF/PLC indoor communication network is proposed. For the proposed system model, the problem of energy efficiency (EE) maximization via power and BH flow optimization is formulated as a non-convex problem, and then transformed into a convex problem via the Dinkelbach’s approach. An energy efficient algorithm is proposed to solve this joint problem to optimality. Simulation results are used to verify the superiority of the proposed hybrid VLC/RF/PLC system and algorithm over a conventional indoor RF system and equal power allocation benchmark scheme, respectively, in terms of network throughput, power consumption, and EE.
- Full Text:
- Authors: Aboagye, Sylvester , Ibrahim, Ahmed , Ngatched, Telex M. N. , Ndjiongue, Alain R. , Dobre, Octavia A.
- Date: 2019
- Subjects: Energy efficiency , Visible light communication , Power line communication
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/399299 , uj:33275 , Citation: Aboagye, S. et al. 2019. Design of energy efficient hybrid VLC/RF/PLC communication system for indoor networks.
- Description: Abstract: Integrating visible light communication (VLC) system with indoor radio frequency (RF) network is seen as a possible way of increasing the capacity and coverage of indoor networks. In such a hybrid network, the traffic generated at the indoor RF and VLC access points must be backhauled to the core network. Power line communication (PLC) technology is seen as a cost-effective backhaul (BH) solution due to its infrastructure availability in every home. In this letter, a novel system model that captures the joint effect of power and BH flow optimization for hybrid VLC/RF/PLC indoor communication network is proposed. For the proposed system model, the problem of energy efficiency (EE) maximization via power and BH flow optimization is formulated as a non-convex problem, and then transformed into a convex problem via the Dinkelbach’s approach. An energy efficient algorithm is proposed to solve this joint problem to optimality. Simulation results are used to verify the superiority of the proposed hybrid VLC/RF/PLC system and algorithm over a conventional indoor RF system and equal power allocation benchmark scheme, respectively, in terms of network throughput, power consumption, and EE.
- Full Text:
Importance and effect of foaming slag on energy efficiency
- Authors: Kipepe, T.M. , Pan, Xiaowei
- Date: 2014
- Subjects: Foaming slag , Energy efficiency , Heat loss , Electrical energy consumption
- Type: Article
- Identifier: uj:4760 , ISSN 978-84-617-0087-5 , http://hdl.handle.net/10210/11763
- Description: The present paper is an overview of the benefit of the foaming slag being used as major elements in the energy efficiency campaign. The aim of this work is to show and demonstrate the importance of using a foaming slag in the furnaces to reduce energy consumption, the heat loss or either to decrease the melting time during the process. Different methodologies have been used according to authors. Some have used injected gases to enhance the creation of the foam, other have added some carbon particles contents which creates a chemical reaction by forming bubbles as a foam and insulator layer. Impressive results have been found and real changes have been made. The results have contributed to different purpose such as: decreasing the global warming by controlling the retaining heat, decreasing the noise and vibration in furnace and finally decrease the use of the electrical energy consumption.
- Full Text:
- Authors: Kipepe, T.M. , Pan, Xiaowei
- Date: 2014
- Subjects: Foaming slag , Energy efficiency , Heat loss , Electrical energy consumption
- Type: Article
- Identifier: uj:4760 , ISSN 978-84-617-0087-5 , http://hdl.handle.net/10210/11763
- Description: The present paper is an overview of the benefit of the foaming slag being used as major elements in the energy efficiency campaign. The aim of this work is to show and demonstrate the importance of using a foaming slag in the furnaces to reduce energy consumption, the heat loss or either to decrease the melting time during the process. Different methodologies have been used according to authors. Some have used injected gases to enhance the creation of the foam, other have added some carbon particles contents which creates a chemical reaction by forming bubbles as a foam and insulator layer. Impressive results have been found and real changes have been made. The results have contributed to different purpose such as: decreasing the global warming by controlling the retaining heat, decreasing the noise and vibration in furnace and finally decrease the use of the electrical energy consumption.
- Full Text:
Use green initiatives for management of logistics industry
- Authors: Sikibi, M. , Steenkamp, H.
- Date: 2020
- Subjects: Energy efficiency , Energy Value Stream Mapping , Green initiatives
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/458263 , uj:40697 , Sikibi, M., Steenkamp, H.: Use green initiatives for management of logistics industry.
- Description: Abstract: In this case study, the warehouse was facing an impending energy crisis. Saving energy, finding and using alternative sources of energy were equally important. The potential benefits of using green initiatives may enhance the strategic process for managing movement and storing products. The purpose of this study was to discuss different approaches to save energy and delay the energy crisis as much as possible. Green and Energy Value Stream Mapping (EVSM) was an efficient approach to show areas where energy was wasted. These approaches reduced energy consumption by 25 c/kWh, which meant each manufactured product can save R4 /kWh. This study proposed Green and EVSM (GEVSM) factors to drive the future of the logistic warehouse.
- Full Text:
- Authors: Sikibi, M. , Steenkamp, H.
- Date: 2020
- Subjects: Energy efficiency , Energy Value Stream Mapping , Green initiatives
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/458263 , uj:40697 , Sikibi, M., Steenkamp, H.: Use green initiatives for management of logistics industry.
- Description: Abstract: In this case study, the warehouse was facing an impending energy crisis. Saving energy, finding and using alternative sources of energy were equally important. The potential benefits of using green initiatives may enhance the strategic process for managing movement and storing products. The purpose of this study was to discuss different approaches to save energy and delay the energy crisis as much as possible. Green and Energy Value Stream Mapping (EVSM) was an efficient approach to show areas where energy was wasted. These approaches reduced energy consumption by 25 c/kWh, which meant each manufactured product can save R4 /kWh. This study proposed Green and EVSM (GEVSM) factors to drive the future of the logistic warehouse.
- Full Text:
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