During the experimental study described in (i) above, the inlet valve of the collector was momentarily opened so that the temperature of water entering the collector was measured hourly. Equally, the fluid outlet temperature was taken during the time
interval. For hourly temperature measurement of the hot water in the tank, the temperature of the stored water at the top stratum of the tank was taken on hourly basis; the need for this was to determine the solar gain for the hour. Precautionary measures were taken to avoid thermal losses associated with over-exposure. The construction framework and the annulus details of the tank are shown in Fig. 3. The completed tank which was connected to solar collectors prior to the experimental