The water tank bridges periods of low insolation and supplies the pressure needed for the irrigation system. One major advantage of solar pumps is that they do not require electrical batteries which are expensive and need a lot of maintenance.
Force of gravity causes the water to flow from the tank to the fields.
The pilot project is also testing units that feed directly into the irrigation system and therefore do not require a water tank. Drip irrigation enables the economical use of water, and its relatively low operating pressure makes it particularly well-suited for combination with photovoltaic pumping systems.