Audio
Solar Groundwater Pumping Components
A solar-powered pumping system includes minimum components such as a:
- water well;
- PV array;
- array mounting bracket and rack;
- pump controller;
- electrical ground for controller;
- DC pump with safety ropes, mount, and well seal;
- wiring;
- discharge tubing or piping;
- storage tank;
- tank flotation switch;
- water taps or access points; and
- security.
If installing a new well, it is recommended to contact a licensed water well contractor. If you are retrofitting a windmill pumping system, the well should be redeveloped to remove biofouling from the sidewalls and sediments from the bottom of the well before installing a solar powered pump.
Pumps 
designed specifically for solar power utilize direct current (DC) and tend to be very efficient, but they usually cost more than a comparably sized alternating current (AC) pump. Surface mounted pumps can be used for a solar-powered pumping system but are discouraged because of their limitations when used in deep wells and because of greater exposure to the elements. Pumps should contain a built-in check valve to keep the water from flowing back into the well.
The size of the pump will depend on several factors including: available water supply, available power, available storage, total dynamic head (TDH), the diameter of well, and water need. A factor of 1.25 times the pump wattage requirements is often used to determine the preliminary size of the required array, but if batteries and a regulator are added into the system the PV array demand will be higher.
The storage tank should be sized to hold at least three days worth of water demand to account for evenings and cloudy days.
For more information, see:
- Solar-powered Groundwater Pumping Systems - CSU Extension
Updated Thursday, May 17, 2012