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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.3 Cape Town  2012


Efficiency and cost analysis of a designed in-line water heating system compared to a conventional water heating system in South Africa



Rupert Gouws; Estie le Roux

School of Electrical, Electronic and Computer Engineering, North-West University, Potchefstroom, South Africa




In this paper, the authors compares the efficiency and cost of a designed in-line water heating system with a conventional water heating system (geyser) in South Africa. The paper provides an overview on water heating systems and heating elements and provides the typical water consumption required by an average household in South Africa. A summary on the design of the in-line water heating system together with a system cost analysis is provided. The designed in-line water heating system takes the energy consumption, temperature and pressure into account during operation. The energy consumption and cost of the designed in-line water heating system is compared to a conventional water geyser. A cost analysis on the designed in-line water heating system, heat pumps and solar water heating systems are also provided. The energy consumption results showed that the conventional water geyser on average consumes 2.5% more energy to heat one litre of water from 15 °C to 60 °C, than the designed in-line water heating system to supply one litre of water at 60°C.

Keywords: efficiency analysis, cost analysis, in-line water heating system, conventional water heating system, design and monitoring



Full text available only in PDF format.




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Received 12 August 2011
Revised 1 May 2012