Faculty of Engineering and Built Environment
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Item Infrastructure delivery management challenges in KwaZulu-Natal : a review of the operations and maintenance module(Seybold Publications, 2024-10-22) Hadebe, Weziwe; Armoed, Zakheeya; Mewomo, ModupeGlobally, governments have prioritized infrastructural policy and infrastructure development as the key to economic development. Efforts to accelerate effective infrastructural delivery in South Africa gave rise to the development of a government-wide tool called the Infrastructural Delivery Management System (IDMS). This was developed as a standardized approach for the planning, budgeting, procurement, operations, maintenance, decision-making and general management of South Africa’s infrastructural development across all tiers of government. The study explores the effectiveness of implementing the Operations and Maintenance (O&M) module of the IDMS in the province of KwaZulu-Natal (KZN). Focusing on the KZN province, the study utilizes a mixed method research approach. Articles were sourced from databases which included Scopus, Web of Science, Google Scholar and Governmental platforms. Peer-reviewed studies in the English language that were published between 2010 to 2024 were identified. Key search terms were infrastructure delivery management system, challenges, operations, maintenance, and efficiency that informed the literature review of the study. The study drew a sample of 133 participants responsible for infrastructural delivery using purposive sampling. Data was analyzed using thematic and content analysis. Findings suggest within the ecosystem of infrastructural development in the KZN province, the necessary IDMS capacity and capabilities do exist. However, the impact of different institutional roles, responsibilities and concurrent functions; in coordinating and implementing the IDMS, has influenced a growing backlog in public infrastructural delivery in KZN. This can be attributed to the failures in coordination resulting in the efficiencies of the O&M module. Through the resurrection of district maintenance workshops and decisive leadership in response to poor operational and maintenance plans, the application of IDMS may prove to be successful in alleviating infrastructure backlogs across all tiers of governance.Item The prospect of floating photovoltaic in clean energy provision and net-zero-emissions(Springer Science and Business Media LLC, 2024) Ebhota, Williams S.; Tabakov, Pavel Y.This study emphasizes the critical role of renewable energy in addressing climate change challenges, particularly in reducing greenhouse gas emissions. It highlights the central importance of solar photovoltaic systems. While recognizing South Africa’s progress in renewable energy deployment, the study notes that substantial efforts are still needed to meet the country’s renewable energy targets. The study’s primary aim is to enhance the understanding and deployment of solar photovoltaic systems by critically examining the photovoltaic potential and performance of different sites. To achieve this, two scenarios—land photovoltaic and floating photovoltaic systems—were considered, focusing on hypothetical 10 MWp-installed capacity systems. The results indicate that the 10-MWp land photovoltaic system has a global tilted irradiance of 2184.7 kWh/m2, an annual total output of 18 GWh, and an average yearly performance ratio of 81%. The economic parameters for the land photovoltaic system include a capital expenditure of $9.0 million, an operational expenditure of $157,500 annually, and a levelised cost of energy of $0.04089/kWh. In contrast, the 10-MWp floating photovoltaic system reports a Global Tilted Irradiance of 1797 kWh/m2, an annual total output of 16 GWh, and a performance ratio of 76%. The economic parameters for the floating photovoltaic system include a capital expenditure of $10.6 million, an operational expenditure of $176,250 annually, and a levelised cost of energy of $0.04936/kWh. Both scenarios’ econo-technical parameters fall within acceptable ranges. However, the land photovoltaic system shows better performance, indicating some efficiency loss in the floating photovoltaic system possibly due to harsher offshore conditions. Based on the data from the reports, the study concludes that the econo-technical feasibility of floating photovoltaic in the Western Cape Province of South Africa is high.Item Optimal design of laminated composite and nanocomposite structures using evolutionary optimization techniques : a survey(2024-09-05) Moyo, Ranaganai T.; Tabakov, Pavel YaroslavovichThe optimal design of laminated composite and nanocomposite (LCNC) structures stands at the forefront of materials engineering, offering the potential to revolutionize the development of advanced materials with superior mechanical, thermal, and electrical properties. By tailoring LCNC structures to meet specific performance requirements, optimizing material usage, and exploring innovative design approaches, engineers can create lighter, more efficient, and environmentally friendly structures that excel in diverse applications. Many industries such as automotive, aerospace, and construction are already using composite and nanocomposite materials to develop high-strength and lightweight structures. Thus, this survey delves into evolutionary optimization techniques as powerful tools for achieving optimal configurations in LCNC structures, highlighting the importance of selecting the appropriate technique for a given optimization problem. A strict selection method was employed to come up with this review paper, and only reputable literary sources were used. The research articles used in this survey were searched from top research databases such as ScienceDirect, IEEE Xplore, Scopus, and Google Scholar. The articles published in the period, 2015 to 2024 were considered. Common design optimization problems such as buckling load, vibration, and weight and cost minimization were covered.Item A survey of home energy management systems and their efficacy in South Africa(IEEE, 2024-03-07) Madushele, Nkosinathi; Tabakov, PavelIn 2022, South Africa experienced a total of 3776 hours of power outages, commonly known as load shedding. This had a significant economic impact, with estimates from the South African Reserve Bank suggesting a Gross Domestic Product (GDP) loss ranging from 0.7% to 3.2%. To address this issue, various initiatives are currently being implemented, including the implementation of renewable energy projects, effective maintenance of existing infrastructure, and a proposal to introduce smart meters to address challenges related to demand-side management (DSM). The electricity market in South Africa is transforming, and this is leading to the emergence of potential technologies that can help address the aforementioned challenges. One such technology is the Home Energy Management System (HEMS). This paper surveys this technology and assesses its potential effectiveness in the South African context.Item An adaptive neuro-fuzzy inference scheme for defect detection and classification of solar Pv cells(Academy Publishing Center, 2024-09-12) Moyo, Ranganai Tawanda; Dewa, Mendon; Romero, Héctor Felipe Mateo; Gómez, Victor Alonso; Aragonés, Jose Ignacio Morales; Hernández-Callejo, LuisThis research paper presents an innovative approach for defect detection and classification of solar photovoltaic (PV) cells using the adaptive neuro-fuzzy inference system (ANFIS) technique. As solar energy continues to be a vital component of the global renewable energy mix, ensuring the reliability and efficiency of PV systems is paramount. Detecting and classifying defects in PV cells are crucial steps toward ensuring optimal performance and longevity of solar panels. Traditional defect detection and classification methods often face challenges in providing precise and adaptable solutions to this complex problem. In this study the researchers pose an ANFIS-based scheme that combines the strengths of neural networks and fuzzy logic to accurately identify and classify various types of defects in solar PV cells. The adaptive learning mechanism of ANFIS enables the model to continuously adapt to changes in operating conditions ensuring robust and reliable defect detection capabilities. The ANFIS model was developed and implemented using MATLAB and a high predicting accuracy was achieved.Item Development of a prioritized traffic light control system for emergency vehicles(Institute of Advanced Engineering and Science (IAES), 2024-10-08) Halleluyah Oluwatobi, Aworinde; Abidemi Emmanuel Adeniyi; Segun Adebayo; Adeniji, Faith; Aroba, Oluwasegun JuliusThis research presents a model for an adaptive traffic signal control system aimed at improving urban traffic regulation. It dynamically adjusts signal timing based on vehicle volume at intersections, prioritizing emergency vehicles by allowing them immediate passage. Utilizing Arduino coding, the system controls traffic light intensity according to the traffic flow, enhancing road safety and efficiency. This innovative approach not only facilitates faster clearance for emergency services without human intervention but also reduces congestion and accident rates. This research creates a model for a prioritized traffic signal control system. When the vehicular volume at the intersection varies, the signal time alters autonomously. It identifies theambulance/emergency vehicles and allows the green light for emergency vehicles like ambulances, and fire engines. This approach may be used to detect traffic accidents and infractions of automobile spiral motions. When erected on the road, the entire system allows for quick traffic clearing for rescue vehicles without requiring a policeman. The system's design eliminates the need for sensors or radio frequency identification (RFID) tags, simplifying traffic management. Simulations validate that emergency vehicle travel time is significantly reduced, proving the system's effectiveness in streamlining urban traffic flows.Item Fabrication and analysis of nanoparticle-infused natural fibre honeycomb core in sandwich structures(2024-05) Govender, Sumeshan; Kanny, Krishnanhis study investigates the feasibility of employing natural fibre materials to fabricate honeycomb core structures, addressing concerns over the environmental impact associated with conventional cores composed of aluminium, Nomex, and petroleum-based materials. The research process involves the fabrication of honeycomb cores utilizing a 3D printed moulding technique, followed by the adhesion of these cores to flax and glass fibre facings, thereby augmenting structural durability. Through the incorporation of cellulose and nanoclay as additives to the adhesive, the investigation reveals a substantial enhancement in flexural strength and impact resistance, surpassing the performance of structures bonded solely with epoxy. However, a notable reduction in compressive strength is observed upon the introduction of these additives to the adhesive. Quantitatively, the study demonstrates that the addition of 3wt% cellulose to the epoxy adhesive results in a remarkable 7.43% increment in flexural strength, a 4.09% increase in yield stress, a 0.17% rise in flexural modulus, a 6.45% enhancement in core shear ultimate strength, a 7.17% increase in facing bending stress, and a 7.94% elevation in absorbed energy. Similarly, the addition of 3wt% nanoclay to the epoxy leads to a significant enhancement, with a 10.48% rise in flexural strength, a 4.09% increase in yield stress, a substantial 20.92% augmentation in flexural modulus, a 10.75% improvement in core shear ultimate strength, a 10.5% increase in facing bending stress, and an elevated absorbed energy by 14.37%. Furthermore, in out-ofplane oriented structures, ultimate compressive strength experiences an increase of 7.32% and 20.1% for cellulose and nanoclay additives, respectively, while compression modulus rises by 6.6% and 29.65%. Nevertheless, it is noteworthy that the structures bonded with nanoclayfilled epoxy exhibit the most favourable overall performance, boasting an ultimate compressive strength of 7.72 MPa and a compression modulus of 7.77 MPa, outperforming their in-plane counterparts due to the larger compressive area of the out-of-plane samples. In terms of tensile properties, the study establishes that hybrid face sheets display an impressive 33.65% higher ultimate tensile strength compared to plain flax fibre samples. Additionally, the hybrid face sheets manifest a 69.45% increase in tensile strength and a substantial 58.73% enhancement in yield stress and Young's modulus, respectively, in contrast to exclusively flax fibre facings. Moreover, the research indicates that hybrid face sheets lead to significantly reduced moisture absorption, with structures employing solely flax fibre face sheets experiencing a mass increase of 11.88% after 168 hours of exposure, while structures utilizing hybrid face sheets encounter a substantially lower mass increase of 6.31%. This corroborates the effectiveness of hybrid face sheets in enhancing the water resistance properties of the composite. In summation, the study underscores the potential of natural fibre honeycomb composite structures to perform comparably to traditional honeycomb materials such as Nomex and aluminium, while being constructed from environmentally sustainable materials. The integration of an efficient additive manufacturing process further bolsters the prospects of these structures, enabling customization and scalability for diverse applications across industries, including aerospace, automotive, and marine sectors.Item Development of integrated model and framework for sustainable energy resources and systems planning(2024-05) Akpan, Joseph Samuel; Oludolapo, Olanrewaju AkanniSustainable energy development (SED) is a crucial component of the Sustainable Development Goals (SDG), aiming to maintain economic and social progress while protecting the environment and mitigating climate change's effects. SED serves as a transition paradigm for sustainable development, providing a blueprint for energy peace and prosperity for people and all uses. The first objective of this dissertation is to identify 10 interlinked themes of SED and explore 2 of them, which are the least studied in existing SED reviews. These two themes include energy financing and commitment to climate change and the need for 100% renewable energy (RE), a part of the decarbonization strategy towards the 1.5 - 2.0 °C Scenario. The study suggests that the current G20 countries' contributions, if done continuously per annum, in addition to 80% more funding from private investment of the same amount in the 1.5°C scenario financial requirement for clean energy, is sufficient to limit global warming. In addition to the present drive for 100% RE for all purposes, an emphasis is placed on addressing other issues, such as energy storage options, developing countries' development agenda, and regional security stability to prevent energy wars. Emerging SED decarbonization strategies are presented across power, transport, building, and industrial sectors. This part concludes with a summary of SED progress and directions for future research, mainly the need for re-defining Nationally Determined Contribution (NDC) through a centralized global or regional stock-taking strategy for greenhouse gas emissions reduction. Consequently, the next study attempts to address the limitations of the current NDC by formulating a policy hypothesis and applying it to an integrated assessment tool (here, termed the environmental model) for strategic stock-taking in reducing GHG emissions. In developing this indexing model, being the first objective of this thesis, we analysed the potential impact of Nationally Determined Contributions (NDCs) under the Paris Agreement on global temperature rise used as the key model input parameters with countries' historical data and other parameters such as GDP, population growth. With the use of an integrated assessment tool based on the concept of system dynamics, the analysis constructs a framework to project global temperature changes under five policy scenarios, namely baseline, current (announced energy policies 1 and 2), and optimum (2.0 0 C Scenario), and most optimum (1.5 0 C) case scenarios. The hypothesis is formulated based on the analysis of current, announced, and best-case global and or applicable national policy scenarios. The model aims to address critical questions regarding the effectiveness of the on-going NDCs commitments in limiting global temperature rise to well below 2 0 C, in alignment with the Paris Agreement's goals. The simulation results offer a roadmap for optimizing the current NDCs in global and national energy policies and treaties, fostering international collaboration, and reinforcing the global commitment to combating climate change. Leveraging on the preceding simulation result of the environmental model, a novel emissions budgeting (EB) model tool (here, termed the economic model) was introduced as a simplified approach for the determination of the economic attractiveness of the policy scenarios of the environmental model. Hence, the second objective, which was to determine the economic benefit of policy scenarios, was achieved. Some advanced countries’ rapid population, economic growth, and energy consumption from mostly 100% electricity that is majorly fossil-based contributes significantly to global CO 2 emissions. In contrast, the case in most developing countries is different. For instance, electricity access in Africa is less than 60%. Hence, this presents challenges and opportunities for achieving the United Nations’ Sustainable Development Goals (SDGs) 7 and 13 of generating all energy from cleaner or low-carbon sources to reduce CO 2 emissions in all countries and combating climate change consequences. Therefore, considering the peculiar situation of other developmental goals, such as increasing population access to electricity while being obliged with the need to transit to complete renewable energy, as our third objective, we explored the idea and transition paradigm of reaching a 100% renewable energy that is void of unjust energy transitioning, climate injustice, and unbiased drive for increasing renewables energy penetration in the global energy mix. The increasing need for renewable energies has been widely acknowledged to greatly advance the climate change agenda as increasing clean energy usage depletes the accumulation of GHG in the atmosphere. Alongside reducing the accumulation of GHG, increasing RE share in the national mix has constantly become the core of many countries' energy policies and the agenda of many of the NDCs reported by countries. Presently, about 30 countries already with over 70% of their national electricity mix from RE. A part of this has birthed a new paradigm and an emerging field of 100% RE for all purposes, recently receiving much attention from academia and in public discourse. Upon establishing the need for analysing the transition towards 100% RE, the thesis demonstrated this conceptual idea through a model (here, termed the energy model) to analyse the possibilities for a 100% renewable energy system at the global level. Because several studies have already done such analysis, however, this has hardly been directly linked to the climate scenarios. Therefore, this thesis bridged this gap in the literature by synthesising the energy transition at different percentage shares in the global primary energy mix over time with the effect on global temperature levels. The rationale behind this was to present a discussion on the pathway possibilities and challenges of achieving 100% RE and whether it is possible to meet the total global energy demand through RE, with what effect on the climate scenarios. To do this analysis, we further define our hypothesis using baseline, optimum, more optimum, and extreme optimum path scenarios to ascertain such possibilities. Finally, we used an integrated assessment model based on the principles of system dynamics to analyse these hypotheses and to find the implications of each action or scenario on other factors such as global temperature, GHG emissions, energy storage breakthrough while keeping the population growth at maximum possible value of 12.4 billion persons by 2100 with GDP growth rate not less than 1.5%. The findings are valuable in helping us discuss if 100% RE can be a reality and what the implications are. Our results show that in the baseline current scenarios, the global average temperature will most likely be kept at 3.3 0 C. Hence, the world would need very urgent and unprecedented efforts beyond the current baseline of business as usual. Interestingly, our findings also indicate that to stay within the 1.5 and 2.0 0 C Scenarios, the world may need just between (58.6 - 77.3) % and (62.7 - 82.8) %, respectively, in the global energy mix. For the most optimistic scenario, (75.5 - 99.8) % RE may be required, and this is able to keep the temperature rise even well below 1.5 0 C but at 1.1 0 C. The 1.1 0 C possibility is quite highly ambitious, in my opinion, because it requires the intensity of global mix energy generation of about 6627 extra joules from renewables only. The major challenge with the idea of 100% RE for all purposes is that achieving such a feat requires a more diverse approach and scarcely are there 100% RE studies that incorporate holistically the interrelation of several pertinent strategies. Therefore, there exists a need to meet both the technical and non-technical requirements. In order to address this shortcoming, our third objective introduces six methodological or evaluation mechanisms (herein, identified as 100% RE evaluation metrics) suitable for existing and future 100% renewable energy analysis. It then reviews energy modelling tools to identify their applicability to 100% RE analysis. The perspectives presented in this thesis are valuable in developing a common integrated methodology and modelling tool for analysing full renewable energy adoption in countries or regions with best trade-offs, using performance indices that have not been previously used. The proposed metrics could also help with proper national and regional energy resources and system planning for new energy projects and installations, contributing to sustainable development. The framework and narrative, presented in the form of a model within this dissertation, make a noteworthy contribution to the ongoing discourse surrounding the energy transition as, to the best of my knowledge, this concept has not been presented this way. The results from this dissertation can be further investigated through a streamlined application of the approach at individual country or regional level to facilitate inclusive and climate-responsive planning and execution strategies for sustainable energy and electricity generation, distribution, and utilization at both national and urban levels. The implications of the findings have the potential to inform the United Nations Framework on Climate Change Convention (UNFCCC) and Conference of Parties (COP) policies in better ways of promoting equitable support for countries, regions, energy consumers, utilities, and prosumers.Item Shifting territories : towards a methodology for a creative emancipatory approach to place-making, the role of Spaza shops in Cornubia, Blackburn, KZN(2024-05) Jahangeer, Mohammud Anwar Noorani; Erwin, KiraThis research argues that the idea of a ‘breaking new ground’ initiative in urban planning demands the effort of unearthing existing alternative practices and attitudes in the pursuit of spatial justice (Soja 2010). The study is located in Cornubia, a large human settlement development on the north coast of KwaZulu-Natal, Durban, South Africa. Contextualised within the national landscape of state-housing provision, and the theoretical lens of place-making and spatial justice, it aims to offer both theoretical and practical insights into the gap between theory and practice in current participatory practices in planning and housing. It explores how creative methodologies may be useful mechanisms for participatory planning, especially in facilitating and translating how residents in housing developments make meaning out of the places they live in. It engages how these may differ, or not, from meaning-making done by state planners and officials. To demonstrate the argument, the thesis uses the example of spaza shops both as a metaphor and a popular initiative. Following on, it suggests that spaza (as creative impulses) owners could take the form of interlocutors who can facilitate dialogue between official top-down planning and quotidian bottom-up operations within the context of the Cornubia development. In doing so, the potential for dialogue in a creative form that already exists ‘informally’ as the popular innovations/manifestations exemplified in the spaza shop, can be revealed. It is in the interstitial space of misunderstanding, where communication often breaks down between the state and the street, that this research has positioned art/creative practice as a way of opening up dialogue within and between individuals, communities, and the state. In addition, arts-based/informed methods, including the use of drawing, Lego blocks, image theatre (drama), and Scrabble are employed as data-generating tools. Furthermore, workshops, focus groups, and face-to-face interviews are conducted to reflect, articulate and reveal the experience of the participants living in a human settlement and their understanding of space and urban planning. The thesis also draws on a series of interviews with the built environment specialists involved both directly and administratively in the project. The objective is to explore the potential for the conceptualisation of powerful catalysts for transformative forms of politics and for providing new sets of resources for urban and spatial thinking Theoretically, the dissertation argues that spazas should be read as popular culture since popular culture is both evasive and resistant (Fiske 1989) and is created “out of the resources, both discursive and material that are provided by the social system that disempowers [the people]” (Fiske 1989:2). Spazas are creative impulses in their own right, developed organically, as critical responses to an environment which has limited access and spaces for the working-class and poor to exercise their various freedoms whether they be economic, spatial, social or cultural.Item Design and application of passive filters for improved power quality in standalone PV system(2024-05) Dlamini, Sandile; Adebiyi, Abayomi Aduragba; Kabeya, MusasaHarmonic components have developed in power systems due to the non-linear properties of the circuit components utilized in power electronics-based products and their rapid application. Power systems rely on fundamental quantities like sinusoidally varying voltage and current, which oscillate at a frequency of 50 Hz. The standard restrictions of IEEE-519-1992 were utilized as a benchmark in this study. To generate the best output, the total harmonic distortion (THD) should be decreased below the limit, even for certain individual harmonic numbers, and reflect the power factor output. Using the results of the simulation and projections for each mitigation strategy, the THDI can be reduced below the IEEE-519 standard whilst also providing cost and electrical advantages. Analysed and modelled is the PV system, which comprises solar panels, a DC-DC converter, a DC-AC inverter, and a non-linear load. Passive filters are an effective solution for improving power quality in standalone photovoltaic (PV) systems. This dissertation provides an overview of the design and application of passive filters for this purpose. Firstly, an introduction to PV systems and the power quality issues associated with them was preferred. Next, different types of passive filters, namely LC filters, LCL filters and LLCL filters, are discussed along with their advantages and disadvantages, and the design considerations for these filters, including the selection of filter components and the calculation of filter parameters. The application of passive filters in standalone PV systems was then discussed, including their implementation in DC-DC converters and Z-Source inverters and, the design of PWM controllers such as the constant boost control method and simple boost control method. The analysis of the outcome of the engineered systems was conducted according to the IEEE standard and SANS 10142 Standard to protect the connected equipment within the off-grid network. The outcomes pertain to the single-phase stand-alone/off-grid photovoltaic system and the single-phase Z-Source inverter. The Z-Source inverter is equipped with two distinct methods for PWM control, namely the constant boost control method and the simple boost control method. All three designs incorporate three passive filters, namely the LC filter, the LCL filter and the LLCL filter. The results were obtained from the network consisting of three distinct designs. LLCL demonstrates superior performance as a passive filter, substantiating its position as the optimal choice. The optimal outcomes of a single-phase off-photovoltaic (PV) network can be achieved using LC, LCL and LLCL filters, with corresponding percentages of 2.99%, 2.45% and 1.71% respectively. Unfiltered was 89.05%, which is not good for the equipment connected to the network. The Z-Source showcases the capability of voltage amplification to an infinite level, rendering it highly effective in minimizing total harmonic distortion. This research investigation further demonstrated the efficacy of the Z-Source Inverter with Constant Control Boost Method and Simple Boost Control Method, achieving unfiltered total harmonic distortion levels of 38.85% and 44.96% respectively. The Z-Source inverter, when combined with the Constant Boost Control method and Simple Boost Control method, exhibits various filter configurations such as LC, LCL, and LLCL filters. In the context of the constant boost control and simple boost control methods, it is imperative to assess the total harmonic distortion percentage of voltage and current for LC, LCL, and LLCL configurations. The constant boost control voltage (LC, LCL, LLCL) and current total harmonic distortion (LC, LCL, LLCL) are measured at 4.177%, 2.655%, 1.951%, and 2.958%, 2.09%,1.465% correspondingly. The voltage-based boost control methods, namely LC, LCL and LLCL, exhibit total harmonic distortion levels of 2.345%, 1.920% and 0.211%, respectively. Similarly, the current-based boost control methods, LC, LCL and LLCL, demonstrate total harmonic distortion levels of 2.346%, 1.921%, 0.211%, and 2.346%, 1.921%, 0.211%, respectively. Finally, the dissertation wrapped up by exploring the potential of passive filters for enhancing power quality in standalone PV systems. The thesis offers a comprehensive investigation of the design and implementation of passive filters in standalone PV systems, providing valuable insights for engineers and researchers in the field. It enhances understanding and utilization of these imperative devices.