Solar pond stability experiments

Abstract

Questions about the long term stability of salinity gradients necessary for the proper operation of nonconvecting salt pond solar collector/storage systems have been raised in earlier feasibility studies. A cooperative experimental effort was established between Battelle-Northwest Laboratories and Oregon State University to investigate some of these questions. The results of a year long experimental study are reported with conclusions drawn to date from partial data reduction. Although severe modeling problems were encountered, generally encouraging observations about the stability of these thermo-haline systems were made. Maximum bottom temperatures of 76°C were obtained as a result of insolation levels below those occurring in field installations. Stable temperature gradients ranging from 150–300°C/m were observed. Slow top and bottom mixing layer growth was the only failure mode noted despite attempts to introduce instabilities at intermediate levels.