A new project will see the municipality exploring ways to extract energy from existing and newly installed water supply and distribution systems.

THE City of Tshwane has introduced a new 15 Ml hydropower reservoir. The Pierre van Ryneveld hydropower reservoir is located in the City of Tshwane's Region 4 (South Region) and will strengthen the capacity of the existing water system.

The Pierre van Ryneveld reservoir is a product of a research project of the University of Pretoria supported by the Water Research Commission (WRC). The project investigated the potential to extract energy from existing and newly installed water supply and distribution systems.

The City of Tshwane will collaborate with the WRC in researching power generation using closed-conduit systems. The practical side of the research was done by the Civil Engineering Department of the University of Pretoria.

The City of Tshwane is exploring the potential of installing hydroelectric generators in water networks where large amounts of energy are dissipated with control valve systems. The pico-hydro plant at Pierre van Ryneveld is a pilot project.

Hydropower development has major potential benefits. Its installation often involves the construction of a weir and a simple intake structure with water transferred by a conduit or canal to a suitable point. Because it needs to be situated on a river with a relatively constant flow and a suitable water drop, it is sometimes referred to as "greenfield" hydropower.

Before opening the Pierre van Ryneveld reservoir, the University of Pretoria, funded by the WRC, installed a hydropower generation pilot unit at the Queenswood reservoir, also situated in Tshwane. The Queenswood reservoir receives its water from Rand Water at a pressure of up to 250 m and has proved to be a huge success.

"Rand Water is currently using about 165 MW to transfer water to various reservoirs of which a large proportion could be used to generate hydropower," says Prof Fanie van Vuuren, a project leader and Head of the Civil Engineering Department of the University of Pretoria.

Prof van Vuuren further says, "At a level of pico-hydropower generation which could benefit rural communities where communication to the world is a primary concern, the first indications are that some energy could be generated from the low flow rate and low head tapped from water supply. In these cases it will be possible to charge batteries and cell phones."

Councillor Percy Zitha, Member of the Mayoral Committee for Public Works and Infrastructure Development, says, "We see this as renewable energy, and it forms part of the City of Tshwane's objective to be a world leader in terms of a programmatic approach to the Clean Development Mechanism. With COP17 now staged in South Africa, the City of Tshwane can draw international attention and illustrate its commitment to reduce greenhouse gas emissions."

Based on the Kyoto Protocol, South Africa approved a White Paper on renewable energy in November 2003, which pushed the use of renewable energy to the forefront.
Now, with COP17, South Africa's Integrated Resource Plan for the period 2010 to 2030 calls for the deployment of 17 800 MW of energy from renewable resources.

Energy is the lifeline of economic and social development worldwide. When considering the current global energy shortages, the emphasis on reducing CO2 emissions, the development of alternative energy generation methods and the growing energy consumption, it is clear that we need to change the way we create and use energy.

The demand for energy increases continuously and needs to be met in order to stimulate worldwide development. Fossil fuels contribute a large percentage of global energy, but due to the dangers of their global environmental impact, there is resistance to expanding it as an energy source.

This forces our current generation to focus on the development of renewable energy sources instead.

Hydropower contributes only 3% of global energy consumption, but this is only a fraction of its potential. Africa is the most underdeveloped continent regarding hydropower generation, with only 6% of its estimated potential being exploited. This is an opportunity for South Africa to contribute to hydropower generation in Africa and the world.

Source: www.tshwane.gov.za