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The Geothermal potential of South Africa
New Challenges for Geoscientists
L. Chevallier 1 , C.Musekiwa 2
1. Council for Geoscience, South Africa, lchevallier@geoscience.org.za
2. Council for Geoscience, South Africa, cmusekiwa@geoscience.org.za
ABSTRACT
Research and exploration in geothermal energy effectively started in many countries more than 30 years ago. These
countries are now technologically well advanced and able to generate power or build thermal stations for a wide
range of applications.
Geothermal energy is now receiving scrutiny in South Africa and the geoscientific community is therefore facing a
major challenge. Indeed, South Africa is lagging behind in this technological field and researchers are acting in a
relatively unknown environment. However, if such research is to start now, it can utilise knowledge and
experiences gained from other organisations around the world.
The scope of the investigation should focus on which types of geothermal source can be targeted in South Africa
and for which type of application? A geothermal potential map will represent the first step towards resource
assessment and its applicability. Geology plays an essential role in defining the geothermal potential of a country.
Favourable geological conditions such as rock types, degree of fracturing, structural framework, deep groundwater
circulation, recent tectonics, heat flow or abnormal temperature gradient, must be present for these various
geothermal systems to occur.
South Africa shows some potential: granites with light abnormal heat flow, hot springs some of them exceeding
50°C, deep sedimentary basins with a thermal gradient above normal, proximity to the possible extension of the
rift system. The hot dry rock (HDR) technology, for instance, which has recently been successfully implemented
for production of electricity in other countries, represents a real challenge for application in South Africa.
The geothermal potential map of South Africa and the inventory of geothermal resources is the basic
tool for a long term geothermal exploration programme in the country. The initiative nevertheless needs
to be driven by extensive national and international collaboration in order to deliver leading expertise
and solutions.
KEYWORDS: Geothermal potential map, geothermal energy.
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