Abstract:
Cheap and reliable electricity is an essential stimulus for economic and social development. Currently
fossil fuels are used for the majority of global electricity generation, but energy shortages and
pressure on all industries to reduce CO2 emissions provide incentives for growing emphasis on the
development of alternative energy-generation methods. Presently hydropower contributes about 17%
of global energy generation, which is only a fraction of its total potential. In Africa only 5% of its
estimated hydropower potential has been exploited, making it the most underdeveloped continent in
terms of hydropower.
An often overlooked source of hydropower energy is found in conduits, where pressure-reducing
stations (PRSs) are installed to dissipate excess energy. The energy dissipated by these devices can
instead be captured as hydroelectricity if turbines are installed in the conduits, either by replacing
pressure-reducing valves (PRVs) with a turbine, or by installing the turbine in parallel with the PRV.
An initial scoping investigation indicated that significant potential exists for small-scale hydropower
installations in water-distribution systems in South Africa. Almost all of the country’s municipalities
and water-supply utilities have pressure-dissipating stations in their water-distribution systems, where
hydropower potential may exist.
This dissertation reflects the development of a Conduit Hydropower Decision Support System
(CHDSS), summarised in a series of flow diagrams that illustrate the developmental process (Figure
i(a) provides an example). A Conduit Hydropower Development (CHD) Tool was developed to
facilitate the calculation of necessary factors (the Phase 1 Economic Analysis is shown in Figure
i(b)). The objective of this CHDSS was to assist municipalities and engineers in identifying conduit
hydropower potential in South Africa and to provide proper guidance for the development of potential
sites.
