SUNScholar - Browsing by Author "Musango, Josephine Kaviti"

Browsing by Author "Musango, Josephine Kaviti"

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Conceptualizing household energy metabolism : a methodological contribution
(MDPI, 2019) Strydom, Adel; Musango, Josephine Kaviti; Currie, Paul K.
Urban metabolism assessments enable the quantification of resource flows, which is useful for finding intervention points for sustainability. At a household level, energy metabolism assessments can reveal intervention points to reshape household energy consumption and inform decision-makers about a more sustainable urban energy system. However, a gap in the current urban metabolism research reveals that existing household energy consumption studies focus on outflows in the form of greenhouse gas emissions, and have been mostly undertaken at the city or national level. To address this gap, this study developed a method to assess household energy metabolism focusing on direct energy inflows in the form of carriers, and through-flows in the form of services, to identify intervention points for sustainability. Then, this method was applied to assess the energy metabolism of different households in Cape Town, South Africa, as categorized by income groups. The study argued that the developed method is useful for undertaking bottom–up household energy metabolic assessments in both formal and informal city settings in which more than one energy carrier is used. In cities where only national or city-level data exists, it provides a method for understanding how different households consume different energy carriers differently.
The correlation between energy cost share, human, and economic development : using time series data from Australasia, Europe, North America, and the BRICS nations
(MDPI, 2018) Roberts, Ryan; Musango, Josephine Kaviti; Brent, Alan Colin; Heun, Matthew Kuperus
This paper investigates how a change in a region’s energy cost share (ECS), a ratio of a region’s energy expenditure as a fraction of its gross domestic product (GDP), affects the region’s social and economic development. Nations from four regions of the world, namely Australasia, Europe, North America, and the BRICS nations (Brazil, Russia, India, China, and South Africa) were chosen for this study. Using time series data from the period of 1978 to 2010, the annual ECS of each country was compared to the year-on-year GDP change, as well as the components of the human development index (HDI). High ECS values were seen to correlate with low economic development. The existence of an ECS threshold was found in 14 of the 15 countries, for all the regions, and for the worldwide analysis, with very strong correlation coefficients obtained for periods of high ECS. New to this field of research, this study also investigated the effects of ECS on gross national income (GNI) per capita change, as well as the effects of 0, 1, 2, and 3 year lags. This investigation found that ECS has a very strong correlation to GNI per capita change, which was much stronger than the correlation between ECS and GDP change. The effects of ECS on social and economic development occurred after varying time lags, and it is unique to each country and region. Regions with similar ECS dynamics were identified, with possible reasons for the similarities being provided.
Determinants of producers’ choice of wine grape cultivars in the South African wine industry
(Stellenbosch : University of Stellenbosch, 2005-12) Musango, Josephine Kaviti; Lombard, J. P.; Mkhabela, T. S.; University of Stellenbosch. Faculty of Agrisciences. Dept. of Agricultural Economics.
The wine industry is one of the oldest commercial activities in South Africa. The South African wine grape industry annually produces more than a million tonnes of grapes, making the country the ninth largest producer in the world. The total area under wine grape production is divided into eight regions for administrative purposes. These boundaries are a legacy of the era of controlled marketing and there is continued meaningfulness of having various classifications such as ‘wine of origin’ scheme. The purpose of this study is to identify the factors that determine the producers’ choice of wine grape cultivars in the wine regions in South Africa. Time series data for the period 1990-2003 were used to estimate the parameters of linear regression models. Two equations for each wine grape cultivar in each region were postulated and estimated using Ordinary Least Squares as applied with Eviews. Further, a stepwise regression as applied in STATISTICA was used to eliminate the parameters that were not statistically significant at five percent significant level. In identifying the factors that determine the choice of wine grape cultivars in the regions, the results showed that each wine grape cultivar in each region has its own factors influencing the producers’ choice of that specific wine grape cultivar. Same wine grape cultivars in different regions similarly have its own factors determining the producers’ choice. The implication of this is that there are differences in terms of the requirements and types of crops and wine grape cultivars grown in each region. However, the most important result that emerged with regular frequency is that, the factors determining the producers’ choice of a specific wine grape cultivar for each region is price of other wine grape cultivars and competitive products in that wine region. The price of specific wine grape cultivars only had an influence on few wine grape cultivars. The implication is that the producers in South Africa appears to consider the prices of other wine grape cultivars and competitive products before making a choice of whether to plant or uproot a specific wine grape cultivar more than the price of the specific wine grape cultivar. This supports the theory that farm prices play a key role in allocating resources and in rewarding efficient producers.
Environmental and natural resource implications of sustainable urban infrastructure systems
(IOP Publishing, 2017) Bergesen, Joseph D.; Suh, Sangwon; Baynes, Timothy M.; Musango, Josephine Kaviti
As cities grow, their environmental and natural resource footprints also tend to grow to keep up with the increasing demand on essential urban services such as passenger transportation, commercial space, and thermal comfort. The urban infrastructure systems, or socio-technical systems providing these services are the major conduits through which natural resources are consumed and environmental impacts are generated. This paper aims to gauge the potential reductions in environmental and resources footprints through urban transformation, including the deployment of resource-efficient socio-technical systems and strategic densification. Using hybrid life cycle assessment approach combined with scenarios, we analyzed the greenhouse gas (GHG) emissions, water use, metal consumption and land use of selected socio-technical systems in 84 cities from the present to 2050. The socio-technical systems analyzed are: (1) bus rapid transit with electric buses, (2) green commercial buildings, and (3) district energy. We developed a baseline model for each city considering gross domestic product, population density, and climate conditions. Then, we overlaid three scenarios on top of the baseline model: (1) decarbonization of electricity, (2) aggressive deployment of resource-efficient socio-technical systems, and (3) strategic urban densification scenarios to each city and quantified their potentials in reducing the environmental and resource impacts of cities by 2050. The results show that, under the baseline scenario, the environmental and natural resource footprints of all 84 cities combined would increase 58%–116% by 2050. The resource-efficient scenario along with strategic densification, however, has the potential to curve down GHG emissions to 17% below the 2010 level in 2050. Such transformation can also limit the increase in all resource footprints to less than 23% relative to 2010. This analysis suggests that resource-efficient urban infrastructure and decarbonization of electricity coupled with strategic densification have a potential to mitigate resources and environmental footprints of growing cities.
Estimating current and future global urban domestic material consumption
(IOP Publishing, 2018) Baynes, Timothy Malcolm; Musango, Josephine Kaviti
Urban material resource requirements are significant at the global level and these are expected to expand with future urban population growth. However, there are no global scale studies on the future material consumption of urban areas. This paper provides estimates of global urban domestic material consumption (DMC) in 2050 using three approaches based on: current gross statistics; a regression model; and a transition theoretic logistic model. All methods use UN urban population projections and assume a simple 'business-as-usual' scenario wherein historical aggregate trends in income and material flow continue into the future. A collation of data for 152 cities provided a year 2000 world average DMC/capita estimate, 12 tons/person/year (±22%), which we combined with UN population projections to produce a first-order estimation of urban DMC at 2050 of ~73 billion tons/year (±22%). Urban DMC/capita was found to be significantly correlated (R 2 > 0.9) to urban GDP/capita and area per person through a power law relation used to obtain a second estimate of 106 billion tons (±33%) in 2050. The inelastic exponent of the power law indicates a global tendency for relative decoupling of direct urban material consumption with increasing income. These estimates are global and influenced by the current proportion of developed-world cities in the global population of cities (and in our sample data). A third method employed a logistic model of transitions in urban DMC/capita with regional resolution. This method estimated global urban DMC to rise from approximately 40 billion tons/year in 2010 to ~90 billion tons/year in 2050 (modelled range: 66–111 billion tons/year). DMC/capita across different regions was estimated to converge from a range of 5–27 tons/person/year in the year 2000 to around 8–17 tons/person/year in 2050. The urban population does not increase proportionally during this period and thus the global average DMC/capita increases from ~12 to ~14 tons/person/year, challenging resource decoupling targets.
Implications for the agriculture sector of a green economy transition in the Western Cape Province of South Africa : a system dynamics modelling approach to food crop production
(Southern African Institute for Industrial Engineering, 2017-05) Van Niekerk, Jacobus Bosman Smit; Brent, A. C.; Musango, Josephine Kaviti; De Kock, Imke Hanlu
ENGLISH ABSTRACT: The Western Cape Provincial government in South Africa has introduced a green economy framework, ‘Green is Smart’, to create a more sustainable economy. This framework stipulates plans for the Western Cape Province to implement more sustainable farming practices for food crop production. While sustainable farming practices will have benefits for the environment, they will also impact food crop production and will require financial investments from stakeholders. To comprehend fully the problem at hand, and to understand better the implications of a green economy transition for the food crop production system, system dynamics modelling was undertaken. The model’s findings highlight that sustainable farming practices will only be financially and environmentally viable if they match the yields of conventional farming practices.
Implications of biofuel production in the Western Cape province, South Africa : a system dynamics modelling approach
(University of Cape Town, Energy Research Centre, 2017) Jonker, Willem; Brent, Alan Colin; Musango, Josephine Kaviti; De Kock, Imke
ENGLISH ABSTRACT: The national government instated a mandatory blending policy to facilitate the uptake and establishment of a biofuels sector in South Africa. Uncertainty exists, however, regarding the implications and effects of producing biofuels within the Western Cape province, as part of a strategy of the province to transition to a green economy. This investigation was carried out as an effort to simulate the biofuel production within the Western Cape under certain project and policy considerations. A system dynamics model was developed to identify key strategic intervention points that could strengthen the business case of biofuel production. The model showed a feasible business case for bioethanol production, with the best case showing an internal rate of return of 23% (without government subsidy), and an emissions reduction of 63% when compared with coal. It is recommended that special consideration be given to the location of bioethanol production facilities, as operational costs can be minimised by incorporating invasive alien land-clearing schemes as part of the bioethanol production. The model further showed that medium-to-large-scale biodiesel production in the province is not feasible under the given model assumptions, as the positive effects of local biodiesel production do not justify the required government subsidy of ZAR 4.30 per litre. It is recommended that a different approach be investigated, where multiple on-site small-scale biodiesel production facilities are used, thus utilising multiple feedstock options and minimising capital expenditure.
Investigating a green economy transition of the electricity sector in the Western Cape Province of South Africa : a system dynamics approach
(Southern African Institute for Industrial Engineering, 2016) Oosthuizen, Juan; Brent, Alan Colin; Musango, Josephine Kaviti; De Kock, Imke H.
ENGLISH ABSTRACT: The Western Cape Government in South Africa has identified the concept of a green economy as a way to transform the Province’s economy to one that is more sustainable from an economic, social, and environmental perspective. System dynamics modelling was used to develop a better understanding of the implications of different green economy policies and investments in the electricity sector of the Western Cape Province. The results suggest that continuing on the current policy path would increase the gap between demand and supply, increase the carbon footprint of the electricity sector, and not provide growth in employment in the sector. Strategic green economy investments are therefore expected to impact positively on a number of indicators across a number of sectors.
Leapfrogging to renewable energy : the opportunity for unmet electricity markets
(Southern African Institute for Industrial Engineering, 2017) Batinge, Benjamin; Musango, Josephine Kaviti; Brent, Alan C.
Electricity plays a crucial role in the socio-economic development of any country. Developing countries, however, unlike their developed counterparts, do not have electricity markets that are fully satisfied, nor are they ‘laden’ with large-scale infrastructure that could create inertia about making the transition. The objective of this paper is to identify the potential trajectories for unmet electricity markets in sub-Saharan Africa to leapfrog to renewable energy as they strive to accelerate access to electricity. The following key drivers of renewable energy leapfrogging in unmet electricity markets were identified from the review: the need to achieve sustainability targets; the availability of renewable energy resources on a sufficient scale; growing investment in renewable energy; maturing niche renewable technologies; a weakening renewable energy cost hypothesis; and a growing population and increasing urbanisation. The paper further conceptualised three potential transition paradigms: revolutionary, scattered, and coned pathways. These paradigms were defined by the pace and magnitude of the transition that can be observed, and depend on the intensity of the identified drivers in a specific unmet electricity market. The paper argues that the largely unmet electricity market in sub-Saharan Africa provides an opportunity to leapfrog the fossil-intensive energy regime to adopt a renewable energy regime.
Some insights about gender-based violence in the Gauteng City-Region (GCR)
(Science and Engineering Publishing Company (SEP), 2013-06) Nyar, Annsilla; Musango, Josephine Kaviti
The article draws on a specific slice of data about gender-based violence from a recent Quality of Life (QoL) survey conducted amongst 16,729 respondents in Gauteng. While gender-based violence comes in multiple forms, the focus of the survey was on spousal or partner violence. The survey posed a provocative statement to respondents about the circumstances under which a man is justified in hitting or beating his wife/partner, i.e. if she goes out without telling him; if she doesn’t look after the children; if she argues with him; if she refuses to have sex with him; if she burns the food; and if she is unfaithful. This article explores the extent to which particular attributes of respondents (sex, race, income, education, participation of men/women; as well as participation in civil society organisations) may account for views that spouse/partner beating or hitting is justified. One finding of interest was that the gender-based violence question ‘if she is unfaithful’ received the strongest response across all the socio-economic characteristics that were evaluated.
Technology assessment of renewable energy sustainability in South Africa
(Stellenbosch : Stellenbosch University, 2012-03) Musango, Josephine Kaviti; Brent, Alan C.; Amigun, Bamikole; Pretorius, Leon; Muller, Hans
ENGLISH ABSTRACT: Technology assessment has changed in nature over the last four decades. It changed from an analytical tool for technology evaluation, which depends heavily on quantitative and qualitative modelling methodologies, into a strategic planning tool for policy-making concerning acceptable new technologies, which depends on participative policy problem analysis. The goal of technology assessment today is to generate policy options for solutions of organisational and societal problems, which at the operational level, utilise new technologies that are publicly acceptable; that is, viable policy options. Energy technology assessment for sustainability is inherently a complex and dynamic process that requires a holistic and transdisciplinary approach. In the South Africa context, specifically, there is no formal and coherent approach to energy technology assessment from a sustainability perspective. Without a formal comprehensive or well integrated technology assessment approach to evaluate the sustainability of any technology, the policy-makers, technology designers, and decision-makers are faced with difficulty in terms of making reasoned decisions about the appropriate technology options. This study developed a framework that incorporates a technology assessment approach, namely, system dynamics, within the broader scope of technology development for sustainability. The framework, termed the Systems Approach to Technology Sustainability Assessment (SATSA), integrates three key elements: technology development, sustainable development, and a dynamic systems approach. The study then provides a guiding process of applying the framework to energy technology assessment theory and practice within the context of sustainable development. Biodiesel, a cleaner burning replacement fuel, argued to potentially contribute to sustainable development, is used for the demonstration. Biodiesel development entails complex interactions of actors such as the technology developers, government at different levels, communities, as well as the natural environment. Different actions or responses in the greater system might hinder or undermine the positive effects of such a development. Based on the SATSA framework, a Bioenergy Technology Sustainability Assessment (BIOTSA) model was developed. The BIOTSA model was used to test the outcomes of a proposed biodiesel production development in the Eastern Cape Province of South Africa on selected sustainability indicators. In addition, some policy scenarios were tested to compare how they assist in improving the selected indicators. The BIOTSA model results are useful in comparing dynamic consequences resulting from a proposed biodiesel production development and the respective policies and decisions that may arise from such a development. The testing and validation of the BIOTSA model was carried out based on structural validity, behavioural validity, and expert opinion. Potential policy scenario outcomes and their implication, on the selected sustainability indicators, were also tested. The opinions of the selected stakeholders indicated that the BIOTSA model was useful in providing an understanding of the potential impacts of the biodiesel development on selected sustainability indicators in the Eastern Cape Province. Thus, the SATSA framework can be applied for assessing sustainability of other renewable energy technologies. In addition, system dynamics provide a useful and a feasible dynamic systems approach for energy technology sustainability assessment. Finally, the model building process and transdisciplinary nature of this study enabled the identification of the potential problems that could arise during the biodiesel production development. In addition, gaps in data and knowledge were identified and the recommendation for future work in this field is highlighted. Nevertheless, the findings of the BIOTSA model could inform policy- and decision-making in biodiesel production development in South Africa. The development of similar models for other renewable energy development efforts is thus recommended. The current efforts to facilitate the large-scale roll out of concentrated solar thermal technologies in Southern Africa, for example, would require the development of a Solar Thermal Technology Sustainability Assessment (SOTTSA) model.
Towards a systemic assessment of gendered energy transition in urban households
(MDPI, 2021-11) Musango, Josephine Kaviti; Bassi, Andrea M.
Assessment of gendered energy transition at an urban scale has emerged as a challenging issue for researchers, policy makers and practitioners. With municipalities becoming players in the energy markets, their involvement raises policy issues that need to be better assessed in supporting gendered energy transition. This paper, therefore, contributes to gendered energy transition assessments at urban household level from a policy maker perspective. We developed a system dynamics model to assess the effects of urban energy policy interventions on household energy consumption and gendered measures using Drakenstein Municipality as a case study. The study used secondary data from various sources for the model parameters. We tested three hypothetical policy scenarios: the business-as-usual, the energy subsidy policy and the energy efficiency policy. The results show that understanding the changes in urban household energy consumption and gendered measures due to energy transition interventions is essential for urban policy planning. The energy subsidy policy scenario was observed to increase total energy consumption but also resulted in socio-environmental impacts that might increase inequality and impair human health. Urban household energy transition interventions need to consider a systems approach to develop decision support tools that capture the cross-sector impacts and inform the development of interventions that promote gendered household energy transition.
Towards urban resource flow estimates in data scarce environments : the case of African cities
(Scientific Research Publishing, 2015-09) Currie, Paul; Lay-Sleeper, Ethan; Fernandez, John E.; Kim, Jenny; Musango, Josephine Kaviti
Data sourcing challenges in African nations have led many African urban infrastructure developments to be implemented with minimal scientific backing to support their success. In some cases this may directly impact a city’s ability to reach service delivery, economic growth and human development goals, let alone the city’s ability to protect ecosystem services upon which it relies. As an attempt to fill this gap, this paper describes an exploratory process used to determine city-level demographic, economic and resource flow data for African nations. The approach makes use of scaling and clustering techniques to form acceptable and utilizable representations of selected African cities. Variables that may serve as the strongest predictors for resource consumption intensity in African nations and cities were explored, in particular, the aspects of the Koppen Climate Zones, estimates of average urban income and GDP, and the influence of urban primacy. It is expected that the approach examined will provide a step towards estimating and understanding African cities and their resource profiles.
Understanding electricity legitimacy dynamics in an urban informal settlement in South Africa : a community based system dynamics approach
(Elsevier, 2019) Smit, Suzanne; Musango, Josephine Kaviti; Brent, Alan C.
The aim of providing affordable, reliable, sustainable, and modern energy for all requires an in-depth understanding of the issues that affect energy access and energy fuel choice, particularly as related to urban informal settlements or slums. Within unequal societies, such as South Africa, a reliance on technical solutions to address access and inequality is inadequate, leading to resistance and protest. Further, introduction of a technical solution – such as solar PV - to address energy access in urban informal settlements, is a complex process, and requires a systems thinking perspective. Using Community Based System Dynamics modelling, this paper therefore investigated the issues that affect energy fuel choice and energy access as related to the introduction of a renewable energy solution in Enkanini informal settlement. Different energy user groups were engaged in the identification of the factors that affect energy access and energy fuel choice; the relationships between these factors in order to improve future interventions; and development of causal loop diagrams to visualise the key feedback loops. The identified factors were economic and market related such as affordability, availability, and land ownership but also included a range of socio-political aspects. 17 feedback loops emerged, of which 13 were reinforcing loops, and 4 were balancing loops. The key feedback loops relate to community empowerment and representation, whilst participation in the political process and the quest for legitimacy through direct electricity connections were recognised as broader issues to be addressed.
Using a system dynamics modelling process to determine the impact of eCar, eBus and eTruck market penetration on carbon emissions in South Africa
(MDPI, 2020) Pillay, Nalini Sooknanan; Brent, Alan Colin; Musango, Josephine Kaviti; Van Geems, Francois
ENGLISH ABSTRACT: The complexities that are inherent in electricity value chains are non-linear in nature and they require unconventional modelling methods, such as system dynamics. This paper provides an overview of the system dynamics method applied for obtaining an understanding of the impact of electric-bus, -car, and -truck market penetration on carbon emissions in South Africa, through the development of the electric mobility simulator (eMobiSim). Two scenarios were tested. The World Reference scenario was based on a market penetration of 22% eCars, 19% eTrucks, and 80% eBuses and the Gross Domestic Product (GDP) scenario was based on 2.38% eCars, 1.79% eTrucks, and 12% eBuses. The results indicate that the World Reference scenario is the most optimistic, with a 12.33% decrease in carbon emissions in the transport sector and an increase of 4.32% in the electricity sector. However, if the economic structure that is specific to South Africa is to be considered and the GDP scenario is run, then there would only be a 1.77% decrease of carbon emissions in the transport sector and an increase of 0.64% in the electricity sector. Although the eCar market penetration produces the highest reduction in carbon emissions, the volumes that are required are large and other factors, such as price parity and affordability in the various income deciles, would have to be considered in determining whether this volume is achievable.
Using an adapted system dynamics approach to determine the linkage between electric vehicle market penetration and affordability
(South African Institute for Industrial Engineering, 2018) Pillay, Nalini Sooknanan; Brent, Alan Colin; Musango, Josephine Kaviti
This paper focuses on an adapted process for system dynamics modelling based on industry experience and the successful implementation of system dynamics models within an electricity utility. The modelling process was demonstrated using a case study of battery electric vehicle (BEV) market penetration in South Africa and its substitution of internal combustion engine vehicle, as a function of affordability based on real disposable income. The results indicate that South Africans are living beyond their “income” constraints and purchasing far more vehicles than what their disposable income allows, with the situation worsening over time. The Gauteng province will have the largest potential to absorb BEVs (81,123) and the highest impact on residential electricity consumption (an additional 4,291 GWh) whilst the lowest is the Northern Cape province with 5,140 BEVs (an equivalent of 272 GWh). However, if disposable income is used as a parametric to determine the affordability of BEVs then there may be 80% less than the expected number of BEVs in terms of market penetration. To benefit from a reduction in carbon emissions in the transport sector, a renewables heavy supply mix would be required else there is not much benefit with South Africa’s current coal heavy supply mix.

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