shows, during the initial stage, tank volume is
inversely proportional to the temperature of the PV panels. The
surface temperature of the PV panels considerably varies after the
tank was refilled with water. The PV panel temperature of the tank
volume of 30 L is higher than that of the 50 L at 9:00e11:20,
12:00e14:00, 14:20e16:20 (totally 4 h and 20 min). The PV panel
temperature of the tank volume of 50 L tank is higher than that of
the 80 L tank from 9:00 AMto 12:00 PM, with minimal temperature
difference. The PV panel temperature of the 50 L tank is lower than
that of the 80 L tank from 12:00 PMto 3:00 PM, with a temperature
difference of approximately 2 Ce10 C. As the solar radiation intensity
rapidly decreased after 4:00 PM, the temperature of the PV
panels is decreased rapidly and temperature difference is unclear