Experimental investigation of stepped solar still with phase change material and external condenser

Abstract

The stepped solar still has a large condensing and receiving surface area compared to the conventional simple solar still. The purpose of this experimental study is to enhance the distillate of the stepped solar still through additional improvers. In the present study, PCM chambers were designed, constructed, fixed to the stepped solar still to improve the productivity rate and stored latent heat during the sunrise which expands the distilled water production time after sunset. Besides, an external condenser has been fabricated to investigate its impact on the performance of the stepped solar still. The experiments have been carried out under the same Iranian climate conditions. For the analysis, four cases have been considered, namely Case I: single stepped solar still, Case II: stepped solar still with an external condenser, Case III: stepped solar still with PCM, and Case IV: stepped solar still with external condenser and PCM. The efficiency of single stepped solar still was 28.21%. The results show that the productivity rate in Case II, Case III, and Case IV improved by 26%, 43%, and 104%, respectively, as compared to Case I. The comparison between four cases of experiments demonstrates the effectiveness of using an external condenser and PCM in stepped solar still.