Storage Tank

Since solar production is, of course, not constant, all pumping systems include a storage tank designed to receive the pumped water when it is available and then distribute it to end users. The bottom of the tank must generally be located above ground level (or above the users’ level) so that the static pressure is sufficient to ensure water distribution by gravity (water tower principle).

The user must define:

• The storage volume of the tank
• The diameter of the tank
• The water level in the tank when it is full (related to volume and diameter)
• The supply method, which can be:
  • Free supply from the top (most common situation). In this case, the supply elevation (relative to ground level) must be defined.
  • Supply from the bottom: the outlet of the pump line is located at the bottom of the tank, which requires a check valve. This operating mode prevents a drop in level between the top and the bottom of the tank and can slightly improve system efficiency, as the level actually used to calculate the manometric head is the tank level at any given moment. The required parameter is the bottom elevation

The tank volume must be sized based on users’ daily needs and the required storage capacity.