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Journal of Energy in Southern Africa

On-line version ISSN 2413-3051
Print version ISSN 1021-447X

J. energy South. Afr. vol.23 n.2 Cape Town  2012


Economic and environmental analysis of solar water heater utilisation in Gauteng Province, South Africa



Enver Doruk Özdemir; Sheetal Dattatraya Marathe; Jan Tomaschek; Audrey Dobbins; Ludger Eltrop

Institute of Energy Economics and the Rational Use of Energy, University of Stuttgart, Stuttgart, Germany




This paper focuses on the energy economics and environmental impacts of solar water heaters (SWH) in the Gauteng Province and compares the results with other technology options for residential water heating with regard to the different income groups. The critical energy situation in South Africa and the highly coal dependent energy generation demonstrates the need to shift to a more sustainable way of living. The residential sector proves to be an optimal starting point to implement new technologies, especially for water heating. The residential hot water demand calculation shows that the annual demand in Gauteng is about 188 million cubic meters. In order to satisfy this demand, different technologies are investigated in this paper, where SWHs lie in focus. Due to the vast income inequality in Gauteng, and also in South Africa, it is obvious that there cannot be one single optimal solution suitable to all households. Therefore, this paper focuses on the differentiation of the residential sector into income groups to show the divergence in warm water demand and the applicability of alternative technologies. In order to analyse appropriate solutions for all income groups, low-cost alternatives are also analysed. The economic analysis shows that although SWHs have higher investment costs than conventional technologies, the payback periods are relatively short (between 3 and 4 years) for high and mid income groups. The payback periods will be even shorter when the planned electricity price tariff increase comes into effect. Furthermore, SWH utilisation has the additional effect of reducing the overall electricity demand up to 70% and greenhouse gas emissions significantly. In addition, SWHs

Keywords: solar water heaters, abatement cost, annual expenditure, GHG emissions, income groups



Full text available only in PDF format.



This research is part of the larger Megacity Research Project, EnerKey, which is a German-South African collaboration to develop an integrated energy and climate change concept for Gauteng Province in South Africa, funded by the German Ministry of Education and Research.

The authors appreciate the efforts of Miraç Gül for data collection, Lyudmyla Reva and Andrea Adam for editing.



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Received 1 October 2010
Revised 25 November 2011

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