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Journal of Energy in Southern Africa

versión On-line ISSN 2413-3051
versión impresa ISSN 1021-447X

J. energy South. Afr. vol.22 no.4 Cape Town  2011


Sustainable cooling alternatives for buildings



Jaco Vorster; Robert Dobson

Department of Mechanical & Mechatronic Engineering, University of Stellenbosch, South Africa




Four sustainable alternative-energy cooling system options are investigated to quantify the actual energy that may be saved when employed in conjunction with conventional air conditioning systems. The four systems considered are active mass cooling, night flushing, roof-spraying and a roof-pond. A one-room building configuration is assumed of which the hourly cooling load and temperature is modelled for both a base case and different combinations of the four sustainable cooling alternative systems. Active mass cooling, night flushing and the roof-spray system proved to be viable options in which the cooling load of an air conditioner may be reduced to maintain a constant room temperature. The roof-spray system showed the most effective results in limiting heat gains to the one-room building and keeping peak room temperatures low.

Keywords: night flushing, active mass cooling, roof-spray, roof-pond, cooling load



Full text available only in pdf format.



This work was supported by KV3 Engineers and the Adaptive Engineering Group, Stellenbosch University.



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Received 10 March 201
Revised 17 June 2011

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