AbstractThe paper deals with the results of preliminary studies on the effect of surface area on the performance of a solar still. Results on the effects of floating coal, compartmentalization and stirring of raw water are reported with respect to a reference still in terms of percentage increase in distillate output. The results show an increase in distillate output in all these cases especially at low water depths and in the presence of solar radiation. The stirring of raw water gave interesting results during daytime which have been explained on the basis of increased aquation of air within the system.