A single-effect diffusion still, instead of a multiple-effect diffusion (MED) still, combined with a tilted wick (1W) still was investigated experimentally under actual weather conditions to investigate whether the natural convection can transport the vapor from the TW still to an MED still adequately. It was found that the single-effect still can be heated by vapor from the TW still and solar radiation absorbed on the single-effect still. From the experiments in summer and autumn, it was found that an MED still can be heated in both seasons whether the MED still absorbs solar radiation directly or not. The experimental results agreed with the calculation results. The total daily amount of distillate, Sigma m(d,total), did not correlate with the daily horizontal solar radiation, Sigma G(day), but strongly correlated with daily solar radiation incident on the still, Sigma G(still). The maximum of Sigma m(d),(total) obtained in experiments was about 4.88 kg/m(2) day when Sigma G(day) and Sigma G(still) were 13.6 and 18.4 MJ/m(2) day, respectively. (C) 2016 Elsevier B.V. All rights reserved.