Comparative study of the effect of depth and season on the performance of the reverse-side absorber-plate shallow solar pond in the Nsukka climate

Abstract

The ‘reverse-side absorber-plate shallow solar pond’ (RASSP), consisting of a semi-cylindrical reflector attached to the exposed base of a conventional shallow solar pond, has been conceived in two variants, viz., one with double glass covers and the other with insulation over the top. The thermal performances of these RASSPs have also been studied analytically to determine the effect of depth variation and time of the year on the maximum water temperatures and overall daily efficiencies they are able to attain. The results of the study, here presented, show that attainable water temperatures decrease while overall daily efficiencies increase as pond depth increases. And that, for a fixed pond depth, the daily peak water temperatures attainable are strongly dependent on the time of the year, while overall daily efficiencies are not. For all seasons and depths, the RASSP with double glass covers is predicted to consistently deliver higher water temperatures but lower overall daily efficiencies compared to the RASSP with top insulation.