In this paper, the thermal performance of a shallow solar pond (SSP) under the open and closed cycle continuous flow heating modes of heat extraction was investigated theoretically and experimentally. Computer programs were developed based on analytical solutions of the energy-balance equations for the various elements of the system. In order to improve the system performance, optimization of the different constructing elements of the system was carried out. Serpentine heat exchangers were inserted within the SSP's water and the storage tank for extracting the heat. Year-round performance of the system under the best configurational and operational conditions was investigated by computer simulation. It was indicated that the present SSP could be used as a heat source for most domestic and low temperature industrial applications all year-round. The daily efficiencies were obtained as 59% and 33% when the pond is operated under the closed and open cycle modes, respectively. Comparisons between experimental and theoretical results showed that the proposed mathematical models could be used for investigating the thermal performance of the SSP with reasonable accuracy. (C) 2013 Elsevier Ltd. All rights reserved.