The global hydropower generation capacity are in the order of 1 060 GWe which represents 19.4% of the global electricity capacity in 2011.
Pumped storage is the largest utilised form of grid energy storage in the world, which represents 96% of storage installations worldwide.
South Africa’s hydro power potential
Water scarcity in South Africa has threatened the viability of hydropower as a renewable source of energy with only a fraction of the potential available being exploited [Van Dijk et al., 2014]. The proportion of hydroelectric power generation in South Africa is small relative to many other developed and developing countries [BP, 2016]. Most of South Africa’s hydro potential is located in the eastern parts of the country.
Hydropower is a mature technology that is currently used in about 160 countries to produce cost-effective, low-carbon, renewable electricity [IRENA, 2015b].
Hindrances for development
Many hindrances for the development of large hydro power projects in South Africa are shared with difficulties experienced by global counterparts, which includes social opposition because of their impact on water availability, ecosystems and the environment, and the need to relocate populations that may be affected by the project. Apart from the requirement of public acceptance, the economics related to such investments includes high initial investment costs, long payback periods, long approval and construction cycles, which continues to hinder the implementation of our hydropower potential on a global level [IRENA, 2015b].
Small-scale hydropower used to play a very important role in the provision of energy to urban and rural areas of South Africa [Barta, 2002]. Globally, small-scale hydropower are often used as an alternative to diesel generators or for rural applications [IRENA, 2015b].
Small-scale hydropower becomes a feasible alternative for rural electrification, especially in remote areas that are located far away from the local and national electricity grid, which is a commonly used option to electricity to isolated or rural communities throughout the world [Van Dijk et al., 2014; Bonthuys et al, 2016].
However, levelised costs (a cost indicator used to evaluate renewable energy technologies, which looks at the full lifecycle cost) for very small-scale hydro power projects are still high when compared to larger hydro power projects [IRENA, 2012c].
Hydro power plants in South Africa
The most predominant water resources suitable for micro hydro power generation are situated in Kwazulu-Natal and the Eastern Cape, with some larger hydro potential utilised at the Vanderkloof and Gariep dams along the Orange river close to the border between the Northern- and Eastern Cape. Both of these are run-of-the-river hydro power schemes [Stephenson, D., 1997]
The most recent hydro projects that proved feasible with the energy business model of the para-statal, Eskom, at the time, was pumped storage, designed to meet peaks during periods of high demand during the day [Oliver, 1975] and to provide vitally important balancing of the overall load of the South African electricity network, comprising of the Drakensberg and Ingula pumped storage scheme located in the Drakensberg.
Figure: Hydro power potential in South Africa [DME, Eskom, CSIR, 2001]
Barta B. (2002) Baseline study – hydropower in South Africa. Department of Minerals and Energy. Capacity Building in Energy Efficiency and Renewable Energy. DME Report No. COWI P54126/EE/RE/70. Department of Minerals and Energy, Pretoria, South Africa.
Bonthuys, G.J., van Dijk, M. & Bhagwan, J.N. (2016) A feasibility and implementation model of small-scale hydropower development for rural electrification in South Africa: A case study of Kwa Madiba SSHP Plant
British Petroleum (2016) ‘Statistical Review of World Energy’
International Renewable Energy Agency (2012c), ‘Renewable Energy Technologies: Cost Analysis Series’, Volume 1: Power Sector Issue 3/5, Hydropower,
International Renewable Energy Agency (2015b) Hydro Power: Technical brief
Oliver, H. (1975) ‘Great dams in Southern Africa’, Cape Town: Purnell
Stephenson, D. (1997) ‘Hydroelectric power potential in South Africa’
Van Dijk, M., Van Vuuren, S.J., Bhagwan, J. & Loots, I. (2014) Small-scale hydropower development for rural electrification in South Africa: Water engineering. Civ. Eng. 22 (5) 42–46.