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Optimization of the design and manufacture of a solar-wind hybrid street light

- Nyemba, Wilson R., Chinguwa, Simon, Mushanguri, Innocent, Mbohwa, Charles

  • Authors: Nyemba, Wilson R. , Chinguwa, Simon , Mushanguri, Innocent , Mbohwa, Charles
  • Date: 2019
  • Subjects: Diffuser , Photovoltaic module , Renewable energy
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/402349 , uj:33666 , Citation: Nyemba, W.R. et al. 2019. Optimization of the design and manufacture of a solar-wind hybrid street light. Procedia Manufacturing, 35:285–290. https://doi.org/10.1016/j.promfg.2019.05.041
  • Description: Abstract: The demand for electricity has escalated and cannot be fulfilled by conventional energy sources alone. There has been a rising demand to seek new renewable energy sources. Although solar and wind energy are the most cost effective renewable energy sources, they are unreliable due to the sporadic nature of their occurrence, if implemented as standalones. In Zimbabwe, solar street lighting has been implemented since 2014 as a solution to the erratic power supplies and outages. Wind potential in Zimbabwe has been identified at elevated heights, with Gweru having the maximum power density of 115 W/m2 at 50 m hub height. This paper presents the optimization of the design of a hybrid renewable energy system (HRES) of solar and wind energy to power a 160W streetlight. The system consisted of a wind turbine, photovoltaic modules, charge controller, battery bank and lights. The system sizing was done in Excel using wind and solar data obtained from the database, HOMER Software Package and PVSyst. The 3D streetlight was modelled using Inventor Professional and a working prototype was manufactured. The results showed that the HRES reduced the energy storage requirements by 38.75% with an overall cost reduction of 14.4%, relative to a standalone solar streetlight. The diffuser effect to the turbine was experimentally assessed, showing 69.3% increase in turbine power output and a 50% decrease in energy storage requirements. Further research can be carried to improve the reliability for standalone systems.
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The effectiveness of solar water heating geysers in South Africa : a review

- Thobejane, Jackson S., Masekameni, Daniel M., Rathebe, Phoka C., Mgwambani, Shalala L.

The future of renewable energy for electricity generation in sub-Saharan Africa

- Adedeji, Paul A, Akinlabi, Stephen, Madushele, Nkosinathi, Olatunji, Obafemi

  • Authors: Adedeji, Paul A , Akinlabi, Stephen , Madushele, Nkosinathi , Olatunji, Obafemi
  • Date: 2019
  • Subjects: Non-linear autoregressive ANN , Renewable energy , sub-Saharan Africa
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/406901 , uj:34229 , Citation: Adedeji, P.A. et al. 2019 : The future of renewable energy for electricity generation in sub-Saharan Africa.
  • Description: Abstract : Energy transition in the last decade has experienced increased quota of renewable energy in the global energy mix. In sub-Saharan Africa (SSA), the transition from the fossil fuel to the renewable energy source has been gradual. The state of renewable energy in the region in the next decade is the focus of this study. This study uses a single-layer perceptron artificial neural network (SLP-ANN) to backcast from 2015 to 2006 and forecast from 2016 to 2020 the percentage of renewable energy for electricity generation, exempting the hydropower in the energy mix of the SSA based on historical data. The backcast percentage renewable energy mix was evaluated using known statistical metrics for accuracy measures. The root mean square error (RMSE), mean absolute deviation (MAD) and mean absolute percentage error (MAPE) obtained were 0.29, 0.18, and 14.69 respectively. The result shows possibility of an increase in the percentage of renewable energy in the electricity sector in the region. In 2020, the percentage of renewable energy in sub-Saharan region is expected to rise to 4.13% with exclusion of the hydropower. With government policies encouraging the growth of the renewable energy as a means of power generation in the region, the predicted percentage and even more can be realized.
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A theoretical pre-assessment of solar photovoltaic electrical production for commerical retail centers

- Van Vuuren, Dirk Johan, Marnewick, Annlizé, Pretorius, Jan-Harm

  • Authors: Van Vuuren, Dirk Johan , Marnewick, Annlizé , Pretorius, Jan-Harm
  • Date: 2018
  • Subjects: Photovoltaic , Renewable energy , Developing economies
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/273140 , uj:29094 , Citation: Van Vuuren, D.J., Marnewick, A. & Pretorius, J.H. 2018. A theoretical pre-assessment of solar photovoltaic electrical production for commerical retail centers.
  • Description: Abstract: The successful implementation of solar photovoltaic technology in retail centers has enabled various consumers the ability to generate and consume electricity on the same premises, reducing electricity costs and dependency on currently utilities. The rooftop mounting solution consists of affixing the photovoltaic modules on existing roof structures of retail centres. Accelerated deployment of photovoltaic technologies in recent history (within developing countries) led to various logistical, technical and bureaucratic barriers arising. A comprehensive understanding of these barriers is required to ensure efficient and effective deployment of the technology in developing countries. This study investigates the assessment considerations for the pre-deployment phase of photovoltaic technologies in retail centres. Environmental-, policy-, technical-, and financial factors are identified as the main barriers affecting the financial viability and Return on Investment of such a project. The evolution of this technology within developing countries and the integration of PV and retail centres are investigated. Finally, various financial evaluation criteria are presented to which the viability of the technology is determined. Understanding of the various barriers ensures effective deployment of the technology in retail centres, commercial and residential sectors of an economy.
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Driving responsible research and innovation: science, society and the energy movement

- Malan, N., Simpson, Z., Janse van Rensburg, N.

Optimal dispatch for a microgrid incorporating renewables and demand response

- Nwulu, Nnamdi I., Xia, Xiaohua

Strategic environmental assessment (sea) supporting the transition to renewable energy in South Africa

- Fischer, Delmarie

  • Authors: Fischer, Delmarie
  • Date: 2017
  • Subjects: Environmental impact analysis , Renewable energy , Strategic planning - Environmental aspects
  • Language: English
  • Type: Doctoral (Thesis)
  • Identifier: http://hdl.handle.net/10210/400995 , uj:33492
  • Description: Abstract : This study addresses the criticism that environmental impact assessment in South Africa, may pose a threat to achieving the development objectives of the National Development Plan, thereby impacting on the ability of the country to deal with the challenges of poverty, inequality and joblessness. The purpose of this study is to identify possible contributions that implementing sector specific Strategic Environmental Assessments (SEAs) can make to improving the efficiency and effectiveness of the project-level impact assessment process, using the renewable energy sector as a pilot. The experience of implementing the energy SEAs will be used to enhance the existing SEA design criteria to enable SEAs to be more easily utilised by the government to influence decision-making and contribute to sustainable development. Possible successes in this sector could translate to other sectors and improve the ability to meet the countries development objectives while promoting sustainability. The energy focus of this study relates to the global concern relating to the impacts of climate change and the commitment of the South African government to transition the country towards a low carbon economy. As part of realising this objective, renewable energy technologies are being advanced through the implementation of the Renewable Energy Independent Power Producers Procurement Programme (REI4P). This programme, which is based on competitive bidding, will see 17.8 GW of renewable energy introduced into the energy mix by 2030. As a pre-bid requirement, prospective bidders must undertake a project level Environmental Impact Assessment (EIA) and be in possession of an Environmental Authorisation. This requirement resulted in over 900 applications for environmental authorisation being submitted for consideration for the first phase of bidding, of which only 9% proceeded to construction. These statistics point to inefficiencies within the procurement and authorisation processes and highlights the need to move to a strategic approach when implementing large scale priority development projects. Data gathering included the review and evaluation of four commercial scale wind-energy environmental impact assessments and two energy sector strategic environmental assessments against previously researched EIA and SEA effectiveness criteria. This research contributes to the debate on the effectiveness of SEA with an emphasis on designing SEAs for implementation. The research would be of interest to environmental practitioners, government and scholars of integrated environmental management. , D.Phil. (Geography)
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The selection of renewable energy technologies and their cost implications for a developing country : the case of South Africa

- Pillay, S., Pretorius, J.H.C., De Canha, D.

Anaerobic digestion for sustainable energy : a brief review

- Kumba, Tresor K., Akinlabi, Esther Titilayo, Madyira, Daniel M.

Energy content and combustion behaviour of loose biomass available in Limpopo

- Shuma, Reuben M., Madyira, Daniel M., Makonese, Tafadzwa N., Oosthuizen, Gert A.

  • Authors: Shuma, Reuben M. , Madyira, Daniel M. , Makonese, Tafadzwa N. , Oosthuizen, Gert A.
  • Date: 2016
  • Subjects: Renewable energy , Solid biomass , Loose biomass
  • Language: English
  • Type: Conference proceeding
  • Identifier: http://hdl.handle.net/10210/92337 , uj:20217 , Citation: Shuma, R.M. et al. 2016. Energy content and combustion behaviour of loose biomass available in Limpopo.
  • Description: Abstract: - Solid biomass continues to be the primary energy source for a significant proportion of Sub-Saharan African society. It is estimated that 80% of energy for heating and cooking in this subcontinent is derived from round wood biomass resulting in estimated annual rate of deforestation of 0.7%. This is unsustainable. This is despite the existence of a substantial resource of loose biomass (forest and agricultural residues) that is produced and disposed of annually. However, one major challenge in harnessing loose biomass as a source of energy is low energy density and poor combustion behaviour. Biomass briquetting technologies can be deployed to improve energy density and combustion behaviour of loose biomass . This requires understanding of the energy content in locally available loose biomass sources. This paper investigates the calorific values (energy content) and combustion behaviour of loose biomass collected from a region in the Limpopo Province of South Africa. The aim of the investigation is to understand the energy value and hence viability of using such loose biomass with the overall goal of developing recipes for biomass briquetting in the region . Calorific values were measured for 12 samples of loose biomass and their combustion behaviour analysed. Certain loose biomass sources are then identified as potential briquetting candidates .
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Renewable energy: deployment and the roles of energy storage

- Masebinu, S. O., Akinlabi, Esther Titilayo, Muzenda, E., Aboyade, A. O.

  • Authors: Masebinu, S. O. , Akinlabi, Esther Titilayo , Muzenda, E. , Aboyade, A. O.
  • Date: 2016
  • Subjects: Energy storage , Environment , Renewable energy , Sustainability
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/93707 , uj:20381 , Citation: Masebinu, S.O. et al. 2016. Renewable energy: deployment and the roles of energy storage.
  • Description: Abstract: Hydro energy still remains the highest RE contributor to electricity generation globally, nevertheless, trends in solar and wind energy has shown increasing investment in RE. Though a decline in investment was observed between 2012 and 2013, yet investment in RE exceeded that of non-RE in the excess of $80 billion dollar. In 2014, investment increased by 16%. As developed countries get saturated with RE technologies, developing countries are now the focus for investment. Wistfully, path dependency problem, lack of adequate infrastructure and policy framework have been highlighted as the major barrier to RE deployment in developing countries. Also, lack of harmonised government agency for RE implementation, incentives and educational gap are the institutional and social barriers. Energy Storage (ES) is being promoted as the “game changer” with capability of smoothening the variability associated with the two RE technologies, wind and solar, with the highest deployment rate. Recent developments are indicative of cost reduction for ES. This paper therefore presents a concise and holistic review of renewable energy (RE) technologies for electricity generation and assess the roles of ES in mitigating intermittency associated with their generation profile.
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Urban environmental benefits of green energy : a review of landfill gas to electricity technologies in eThekwini, South Africa

- Gumbo, T.

  • Authors: Gumbo, T.
  • Date: 2016
  • Subjects: Renewable energy , Landfill gas , Environment
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/214068 , uj:21232 , Citation: Gumbo, T. 2016. Urban environmental benefits of green energy : a review of landfill gas to electricity technologies in eThekwini, South Africa.
  • Description: Abstract: In the quest to ameliorate the negative developments emanating from a heavy reliance on fossil fuels, there has been a surge in the development, adoption and utilisation of renewable energy technologies all over the world. Adopting a case study and phenomenological research design and applying qualitative approaches, this study focuses on the environmental benefits directly emanating from the development, adoption and application of innovative technologies in renewable energy generation and supply. In particular it assesses the experiences of municipal solid waste-to-energy technologies in the eThekwini Metropolitan Municipality, South Africa. The results reveal that the innovative projects have resulted not only in improved municipal solid waste management, but more importantly improved urban environmental conservation. The paper concludes by recommending the scaling up of such innovative projects within South Africa and the adoption and application of these best practices to other African countries.
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Energy and environmental assessment of industrial hemp for building applications : a review

- Ingrao, Carlo, Lo Giudice, Agata, Bacenetti, Jacopo, Tricase, Caterina, Dotelli, Giovanni, Fiala, Marco, Siracusa, Valentina, Mbohwa, Charles

  • Authors: Ingrao, Carlo , Lo Giudice, Agata , Bacenetti, Jacopo , Tricase, Caterina , Dotelli, Giovanni , Fiala, Marco , Siracusa, Valentina , Mbohwa, Charles
  • Date: 2015-06-01
  • Subjects: Renewable energy , Industrial hemp , Sustainable buildings
  • Type: Article
  • Identifier: uj:5226 , ISSN 13640321 , http://hdl.handle.net/10210/14552
  • Description: Buildings significantly contribute to global environmental pollution due to consumption of both natural and primary-energy resources as well as to emission of carbon dioxide in their life-cycles. Therefore, to enable construction of more sustainable buildings, it is important and urgent that new low-environmental impact materials are developed, mainly by reducing the use of non-renewable resources. In this regard, the recent advances in the development of natural fibres represent a significant opportunity to produce improved-materials and energy from renewable resources. For this purpose, assessments of energy and environmental performances are needed to support both the design and the production of the aforementioned materials so as to identify solutions for enhanced contribution to global sustainability. In this context, this study presented a review of the papers published so far that have focussed upon the assessment of the environmental and energy impacts related to the use of hemp-based materials for building applications. The reviewed studies aimed at testing and improving hygro-thermal properties and eco-friendliness of these materials so as to enable reduction of both embodied and operational energy, whilst preserving both indoor air quality and comfort. Doing so would enable limiting the use of energy resources and, as a consequence, their impacts to human health and to the environment, so contributing to making buildings healthier and more environmentally sustainable throughout their life-cycles. Based upon the findings of the studies reviewed these materials have strengths and weaknesses and their use is strictly dependent on the given structural situation and on specific requirements of thermal, moisture, fire and sound protection. In particular, all studies concluded that the main strength in the use of hemp-based materials comes from the production phase because of the “green” origin of these materials, mainly associated with the carbon sequestration during plantation growth.
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Energy content and combustion behaviour of loose biomass available in Limpopo

- Shuma, Rueben M., Madyira, Daniel M., Makonese, Tafadzwa, Oosthuizen, Gert A.

  • Authors: Shuma, Rueben M. , Madyira, Daniel M. , Makonese, Tafadzwa , Oosthuizen, Gert A.
  • Date: 2015-03-31
  • Subjects: Renewable energy , Solid biomass , Combustion
  • Type: Article
  • Identifier: uj:5150 , ISBN 9781479979127 , http://hdl.handle.net/10210/14220
  • Description: Solid biomass continues to be the primary energy source for a significant proportion of Sub-Saharan African society. It is estimated that 80% of energy for heating and cooking in this subcontinent is derived from round wood biomass resulting in estimated annual rate of deforestation of 0.7%. This is unsustainable. This is despite the existence of a substantial resource of loose biomass (forest and agricultural residues) that is produced and disposed of annually. However, one major challenge in harnessing loose biomass as a source of energy is low energy density and poor combustion behaviour. Biomass briquetting technologies can be deployed to improve energy density and combustion behaviour of loose biomass. This requires understanding of the energy content in locally available loose biomass sources. This paper investigates the calorific values (energy content) and combustion behaviour of loose biomass collected from a region in the Limpopo Province of South Africa. The aim of the investigation is to understand the energy value and hence viability of using such loose biomass with the overall goal of developing recipes for biomass briquetting in the region. Calorific values were measured for 12 samples of loose biomass and their combustion behaviour analysed. Certain loose biomass sources are then identified as potential briquetting candidates.
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Performance evaluation of a nine-phase self-excited induction generator

- Mangena, G.C, Muteba, M.

  • Authors: Mangena, G.C , Muteba, M.
  • Date: 2015-01-28
  • Subjects: Renewable energy , Self-excited induction generators , Self-excited nine-phase induction generators
  • Type: Article
  • Identifier: uj:5104 , ISBN 978-0-86970-786-9 , http://hdl.handle.net/10210/13925
  • Description: This paper evaluates the performance of a self-excited nine-phase induction generator. The advantage of using Multi-phases(more than three-phases)are well known such as High power handling capability by dividing the required power between multiple phases, higher reliability, reduced harmonics and Fault tolerant. For a nine-phase machine, if failure occurs the machine can still operate since each three phase group can be made independent from each other. In this study, mathematical model is developed directly from the equivalent circuit of nine-phase self-excited induction generator by means of nodal admittance method. The stator of a conventional 1.5 kW, 4-pole, 50 Hz three-phase squirrel cage induction machine has been modified to nine-phase induction machine. The excitation is provided by 9 capacitors each rated 40 uF and 450 V.
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Technology in Africa for sustainable alternative energy growth : an innovative bird eye view

- Agbenyeku, Emmanuel Emem-Obong, Muzenda, Edison, Msibi, Innocent Mandla

  • Authors: Agbenyeku, Emmanuel Emem-Obong , Muzenda, Edison , Msibi, Innocent Mandla
  • Date: 2015
  • Subjects: Renewable energy , Electricity , Innovative learning
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/73433 , uj:18410 , Citation: Agbenyeku, E.E., Muzenda, E. & Msibi, I.M. 2015. Technology in Africa for sustainable alternative energy growth : an innovative bird eye view.
  • Description: Abstract: Over the last decade, numerous ideas have insistently emerged and triggered several social, economic and environmental discuss emanating from energy insufficiencies in Africa. A lot around energy poverty are currently argued particularly, on how chiefly Africa’s industrialization is prime to its potential sustainability across all facets of growth and development. Sadly, only few member countries since post-colonialism have earnestly attempted innovative approaches towards new alternative energy schemes. Nonetheless, wasteful sums have drowned in projects of less critical nature. For this reason; an innovative bird eye view (IBEV) portrayed how member countries might augment rates of dispensable energy to increase access to electricity. Hence, versatile industrialization via renewable and greener alternative energy sources can be reached. The employed measures herein, extend past industries and research institutes to involve cultural, institutional, economic and political players of key positions in innovative process. Firstly, a conceptual idea of “learning” was conveyed as vital to IBEV, seeing innovation and production as pertinent and dynamic. On a second note, the work featured instances of trials to create renewable energy industries around the continent. Lastly, the possible transformation of research outlets such as the African Network for Solar Energy (ANSOLE) into inventions was highlighted, emphasizing how innovations might be born from inventions. A vital policy suggestion was that divisions of African “innovative force” such as a technological head like South Africa can for example; engage more with member countries involved in production or assembly while creating beneficial agreements with them. Thus, with mixed innovation schemes, more effective knowledge transfer can be groomed across the continent.
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