Hydropower is recognised world-wide as a robust and well tested renewable energy technology in the electricity generation sector, preferred due to a high efficiency energy conversion process.  Modern installations can convert up to 95 percent of the energy of moving water into electricity. On the other hand the development of hydropower is very site specific and requires generally a multitude of disciplines in its development stages. Small scale hydroelectric (SSHE) installations are recognized as exemplary renewable energy converters producing minimal quantities of Carbon and other emission gases during construction and operating life of a generation system. Hydropower generation is an entirely non-consumptive use of water in contrary to any other uses where water is an essential ingredient.

Categories of small scale hydropower

Historically, small scale hydroelectricity generation has been a significant component of the yester-year electricity production in several parts of South Africa, mainly for urban settlements situated along the eastern side of the Drakensberg Mountain range. The first known SSHE plant was installed in 1885 at the foothill of the Table Mountain in Cape Town. There are a few more surviving old SSHE plants situated around South Africa most of them as out-of-operation plants.

For the recent fifty years no extensive development of hydropower for electricity generation has been considered in the South African energy sector. With no demand for hydroelectric equipment a vacuum has been created in the manufacturing sector and at present all hydroelectric equipment for the small and large hydropower installations has to be imported to South Africa.  Local capacity exists for smaller systems. Two pumped storage schemes for the peak generation and two storage controlled macro plants were built at large water supply dam storages situated on the Orange River from state funding in these recent decades. No one small scale hydroelectric plant has been built during the same period. At present the overall hydroelectricity generation capacity represents only about 5 percent of present total 45 500 MW installed generation capacity in South Africa. 

Although it is acknowledged that South Africa is not endowed with the best hydropower conditions in the world, supplying water over long distances and elevations is common for domestic, industrial and irrigation water transport schemes. Infrastructure assets which allow for daily water transport (such as tunnels, pipelines and canals.) or environmental water releases (e.g. from the large and medium dams) were identified as potential sources for the small scale hydroelectricity generation in now-a-day South Africa.

The combined overall potential in developing “green” hydropower from a variety of existing hydraulic infrastructure (e.g. dams, weirs, irrigation canals and large gravity water supply carriers) and new water supply/hydropower generation dam sites in South Africa is estimated at 2050 MW. There is a good potential of some 5 200 MW for a “green-field” diversion fed hydropower plants in the Eastern Cape and KwaZulu-Natal provinces. There is however almost unlimited potential for “green” hydroelectricity imported from the countries north of South Africa. The firm potential of future pumped storage hydropower schemes evaluated by the ESKOM is in order of 10 200 MW.