Water is a universal need and pumping is a major energy issue, especially in regions where there is no grid or where electricity is expensive or unreliable. Solar pumping provides access to water in a clean and quiet way, in remote and hard to reach places, and can be a replacement for diesel pumps. Demand for water is often greatest when solar irradiation levels are high, which makes PV an ideal power source.
Water is pumped by the solar system when the sun shines, and is usually stored in a tank and used when required. Pumping systems do not have batteries.
The main components are:
- PV modules
- Pump controller (for either a DC pump or an AC pump)
- Tank to store water
The main applications are:
- Drinking water for homes and communities
- Water for livestock
- Water for crop irrigation
Complete systems (PV modules, controller, pump) are usually purchased from a single supplier.
Typical solar pumping system.
The PV modules produce electricity to drive the pump. The controller ensures that this is done efficiently. The water is pumped to a tank for later use, but can also be used directly, for example in irrigation systems.
Diesel and grid-connected electric pumping systems are usually designed to pump a large quantity of water over a short time period. Solar pumps pump the water more slowly but over a longer time period. This needs to be taken into account when selecting/designing a water supply system using solar pumping.
Solar water pumping can also be used in water treatment plants, for swimming pools, and in many other situations.