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Theses and dissertations (Engineering and Built Environment)

Permanent URI for this collectionhttp://ir-dev.dut.ac.za/handle/10321/10

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    Evaluation of water resource management systems in eThekwini Municipality
    (2024-05) Faya, Nosipho Buhle; Anugwo, Iruka C.; Twala, Bhekisipho
    Water is an essential and critical resource for human, animal and plant survival and our continuing existence on planet earth. Water is increasingly becoming a scarce resource, and the issue of water scarcity has been exacerbated in intensity by climate change, as well as aging water resource infrastructure in many countries; such as the republic of South Africa. This study aimed at evaluating the water resource management systems, in that is rooted in a qualitative research method and phenomenological paradigm. Thus, primary data were collected from personnel in high and strategic positions in the government entity, eThekwini Municipality Water and Sanitation. This qualitative data was then subjected to content analysis and themes. The study findings are based on the eThekwini region and its resiliency and adaptability to climate change. In order to achieve that, this study utilized an in-depth interview and semi-structured interview approach to garner respondents’ perceptions, opinions, expertise, judgement and experiences on issues of water resources management systems and infrastructure resiliency and adaptability to the impact of climate change in Durban. The data revealed that the current state of water resource infrastructure is not satisfactory, or resilient enough to withstand the impact of climate. The study findings also indicated the urgent need for the eThekwini municipality’s water resource infrastructure to be upgraded for optimal operation and for resiliency to environmental and technical challenges. The study further reveals that the eThekwini municipality is considering embarking on joint venture projects that would adopt the innovative concept of reusing, remixing and recycling treated wastewater, as well as the installation of desalination plants for effective water resources management. From our findings, we saw that eThekwini municipality needs to adopt new technologies that would enable integrated and adaptive, resilient components in their water resource management systems. The study recommended that eThekwini municipality should endeavour to strive towards upgrading the current state of its water resource infrastructure so that it is in a satisfactory state, and resilient enough to withstand impact of climate change.
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    Appraisal and optimization of energy-efficient green buildings in South Africa
    (2024-05) Agbajor, Favour David; Mewomo, Modupe Cecilia
    Generally, over 35% of global energy use and 40% of carbon emissions are attributed to the built environment while future forecasts indicate that these values may rise much further. In South Africa (SA), building stocks account for 40% of the country’s final energy demand which strains the country's coal-dependent energy grid and oftentimes results in power outages. Optimizing energy efficiency and thermal comfort while attaining the lofty goal of carbon neutrality is essential for all concerned stakeholders in the building sector globally. Meanwhile, green building (GB), being a recognized revolutionary theory and practice in the building industry, is suggested as a solution to SA’s environmental challenges. On this wise, this research aimed to develop energy-efficient models for optimizing green buildings into the design and operation of buildings to allay their environmental impacts. The goal was to enhance energy efficiency, decrease energy consumption, and mitigate carbon emissions across diverse climates, thus benefiting South Africa's built environment. To achieve the study's goals, three primary research objectives were identified and pursued namely: (i) To provide an overview on status-quo of green building development in South Africa with a view to explore the status quo and provide roadmap for improvement; (ii)To examine the energy-saving potential of incorporating building-integrated greenery systems towards climate-resilience in the subtropical climate zone of South Africa; and (iii) To investigate the energy-performance of green building renewable energy utilization systems within South Africa’s hot and arid climate zones. Initially, the study's first objective entailed a comprehensive literature overview integrating climate, sustainability, and building energy modeling within the South African context. This was carried out through a scoping review approach via the PRISMA guideline of reporting Subsequent objectives involved selecting reference buildings and creating hypothesized models as case studies based on six climate zones from the South African National Standard. For the second objective, a thorough and integrative approach that linked building energy modelling and varying climatic change was devised. The numerical parametric simulation and analysis, being a quantitative research approach was adopted as a data collection method. Similarly, the third objective employed numerical parametric simulation as a data gathering method in this research, which is based on a quantitative analysis to explore various design options iteratively. In the second and third objectives, Global climate databases, Meteonorm, Climate Consultant, and energy simulation software such as DesignBuilder, EnergyPlus, and Polysun were used for weather data analysis, climate modeling, and building energy simulation. The findings highlighted that while South Africa boasts notable green construction projects, scientific research progress has not matched international levels. The focus was on promoting green building adoption through standards, certifications, and incentives. However, gaps were observed in optimized energy performance and post-occupancy evaluation of existing buildings. Despite high awareness, the utilization of green building technologies among South African professionals did not meet anticipated levels. For the second objective, the study's findings indicated an increase in extreme heat waves with higher peak temperatures in the future. Building energy use in the study area is projected to rise by 8-24% from 2030 to 2080. Notably, heat gains primarily result from envelope thermal transfer rather than solar radiation. Greenery systems were found to effectively support green building goals and urban sustainability across anticipated seasons. Nature-based solutions proved successful in adapting to climate change compared to non-retrofitted conventional buildings. For the last objective, the study revealed regions with substantial solar irradiance, indicating potential for renewable energy adoption. It emphasized the need for durable BIPV systems in hightemperature conditions. BIPV modules generated more energy in Upington than Nelspruit due to varying solar radiation. Opportunities were identified for BIPV systems to achieve optimal power generation. The study provides a foundation for informed decision-making, policy formulation, and targeted research in sustainable building practices. The study presents practical principles to guide urban planners and policymakers in integrating eco-friendly technology into both new and existing building designs. This promotes sustainable urban development and reduces cities' carbon emissions. Going forward, to showcase the effectiveness of these energy-efficient and climate-responsive systems to the public and industry stakeholders, it is recommended to establish and enhance largescale demonstration projects in South Africa's subtropical, hot and arid regions.
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    Long-term water conservation and demand management for Umgeni Water in Kwa-Zulu Natal
    (2023-09) Nagan, Vernon; Seyam, Mohammed
    South Africa is considered a water-scarce country and is anticipated to encounter extensive water deficits in almost all its water management areas by 2025. Due to water scarcity, adequate resource management and planning are required to sustain its water resources. From 2015-2019 the country faced severe water shortages, which forced many provinces to implement water restrictions as a water conservation and demand management strategy. South Africa faces several obstacles regarding water management, such as long periods of inadequate rainfall, population growth, and excessive water losses, to name a few. South Africa has developed most of its water resources with limited scope for further development. The study focuses mainly on the Mgeni system, which consists of Upper and Lower Mgeni systems managed by Umgeni Water, the main supplier of potable water to most of the Kwa-Zulu Natal province. The Mgeni System is recognised as the main source of water supply in the Durban and Pietermaritzburg region situated in South Africa. The Durban-Pietermaritzburg region is the primary economic hub of Kwa-Zulu Natal, and this will bring about a high level of demographical pressure and water supply problems. The study's objective was to (i) analyse the study area to assess whether there will be sufficient supply to meet future demand with climate and demographic impacts, (ii) identify the quantity and causes of current water losses within the study area and to assess the Key Performance Indicators, and (iii) to evaluate efficient strategies, tools, and measures for water conservation and demand management which will reduce water losses in future years. The study adopts both quantitative and qualitative analysis. The quantitative analysis investigates the water supply and demand situation in the Mgeni System catchment and evaluates the future supply and demand accounting based on Water Evaluation and Planning (WEAP) software. The WEAP model is used to analyse the study area from 2009 to 2050 to develop outcomes scenarios that visualise future water supply shortfalls with current data inputs. The assessment model is computed based on four scenarios such as varying population growth rates and impacts of extended dry climates. The qualitative analysis utilises questionnaires to investigate the current WC/DM strategies. The qualitative method involves data collection from structured questionnaires targeting Umgeni Water department with thorough water conservation and demand management knowledge. The study found that the Mgeni catchment is relatively sensitive to changes in population growth, which will significantly alter water availability. Furthermore, an extended dry climate will cause a water supply deficit, thus exposing the study area to water scarcity problems. The study results also indicate that Umgeni Water currently has water conservation and demand management strategies and interventions in place, but it requires more investment from stakeholders to produce the required benefits. In response to the future water demands, the only way one can overcome the unmet demand is by introducing water conservation and demand management strategies such as pressure management, active leak detection testing to reduce the water losses encountered, as well as education and awareness which forms an integral part of the initiative. By implementing these strategies, water losses can be reduced, preventing early water scarcity, and giving decisionmakers time to provide further solutions to the water problems in the study area.