Operation of a Small-Scale saltgradient solar pond: Experimental results

A small-scale sodium chloride salt gradient solar pond was operated outdoors in Dhahran over a period of nine months. Vertical temperature profiles in the pond and in the ground underneath the pond, density profiles and temperatures at fixed locations in the pond were measured. Variation of the bottom zone temperature with time over the operating period is presented as well as representative vertical pond temperature profiles taken in the morning and afternoon. From these profiles and additional temperature data taken from fixed locations in the bottom zone, some insight was gained regarding onset of bottom convection and the midday total energy collection. Evidence is shown which suggests that weak convective cells in the gradient zone will “self-heal” even when on the order of 5 cm in thickness.