Recognising the change in land use patterns and its impacts on energy demand and emissions in Gauteng, South Africa

Abstract

The economic powerhouse of South Africa, Gauteng, has seen rapid urban growth since its formation in the early nineties. Today, more than 90% of its population lives in urban areas. The sudden rapid urban growth over such a small period has resulted in dispersed spatial structure. The thesis aims at recognising the change in the land use pattern and its impacts on energy demand and emissions in Gauteng. Furthermore, based on a scenario analysis, recommendations were drawn with regard to future urban sprawl and emission mitigation measures. At the moment, there is no scientific research available which deals with the complex phenomenon of urban growth and its impact on energy and emissions in Gauteng. In the thesis, the change in land use patterns between 1991 and 2009 in Gauteng was analysed which confirms that the region is affected by urban sprawl. Furthermore, based on two scenarios, the future urban developments in the region till 2040 were simulated using a cellular automata model. The scenario analysis concludes that the outward expansion of Gauteng must be restricted within the existing urban boundary to stop further sprawl. In Gauteng, the residential sector is the third largest energy consumer and has the second largest share in greenhouse gas (GHG) emissions. Heavily coal-based electricity generation (around 93%), a high share of fossil fuels used by the households and use of inefficient energy technologies are the main reasons for high GHG emissions in the residential sector in Gauteng. Furthermore, the income disparity is also mirrored in the energy consumption patterns in Gauteng. Most of the poor households are struggling to gain access to electricity, whereas the rich communities are met with frequent power cuts. As the government tries to reduce the share of coal and other fossil fuels to achieve mitigation targets, reduction in energy consumption plays a major role in Gauteng. A comprehensive analysis based on various income groups and dwelling types was carried out to understand the energy consumption patterns in the residential sector. The scenario analysis also reveals how the share of different energy carriers used by households and their share in the final energy consumption affect the GHG emissions. The spatial distribution of the final energy demand in the residential sector helped in identifying energy intensive as well low energy demand areas in Gauteng. Energy intensive areas are located near the economically developed regions such as central business districts (CBD) in Johannesburg and Pretoria. The spatially explicit energy consumption could be a valuable tool for determining policies for implementing energy efficiency and renewable energy programs at the local level. Though the residential sector is not the highest energy consumer in Gauteng, the consumption and emissions in this sector can be easily influenced by the government by introducing various subsidies and incentives for renewable energy which would also help in minimising the high share of direct emissions by 2040. In addition, a thorough potential analysis for energy generation from woody biomass, energy crops, photovoltaic (rooftop and open space), solar water heaters and wind energy was carried out at the municipal and the provincial level which exhibits various possibilities to implement the use of renewable energy in the region. To sum up the thesis, the developed simulation model has been proven suitable to understand future urban patterns of a fast growing region like Gauteng. The simulated land use pattern would help in understanding what problems will occur in the future, as well as preparing the government to tackle these issues and develop new energy policies and strategies for Gauteng. Additionally, the spatial distribution of energy demand and renewable energy potential, which was assessed using a GIS-based model, helped in providing energy efficient and renewable energy-based solutions at the local level. It can be concluded that the constantly rising residential energy demand is not heavily influenced by the urban pattern and can only be reduced by increased use of efficient technologies and energy saving measures.