New research at the University of Pretoria, with support from the Water Research Commission, reveals South Africa could meet much of its future electricity requirement from hydro-electric dams.

"Currently, hydro contributes about 17 per cent of global energy production, and Africa is the most underdeveloped continent with regard to hydro generation, with only 5 per cent of its estimated potential exploited," says the report.

Researchers highlighted three key dams in South Africa, which could be used as power generators. The country has 278 municipalities and various water supply utilities, almost all of which have pressure-dissipating stations in their water distribution systems.

"Energy found in water supply conduits is often disregarded as a source of electricity, but numerous transfer schemes and distribution systems offer potential," they said. "Pressure-reducing stations are installed to dissipate excess energy along a conduit, as well as upstream of water treatment plants and reservoirs. The energy dissipated could instead be used to generate electricity through the installation of hydro turbines in the conduit."

Currently there is no substantial development in South Africa’s conduit hydro market, despite its significant potential, "due largely to a lack of knowledge and technical understanding".

But researchers found the total generation potential was difficult to establish because there was no data. So it designed the Conduit Hydropower Decision Support System (CHDSS) and a few municipalities are already offering tenders for hydro electric systems.

The Water Research Commission says: "Already, utility Bloemwater has installed a 96 kW, and Tshwane has installed a 150 kW plant and begun tendering for a 2.4 MW plant. Rand Water and Johannesburg Water have also put out tenders for 12 MW and 5 MW projects, respectively.