A solar borehole pump runs directly off solar panels, so it keeps pumping during power cuts and costs nothing to run. On the Highveld, with plenty of sunshine, it's a popular upgrade, especially on smallholdings.
How it works
- Solar panels power a DC or hybrid pump through a controller.
- The pump runs while the sun shines and fills a storage tank (JoJo-type). The house, garden and animals draw from the tank, often with a small pressure pump.
- Hybrid systems can also run off mains or an inverter at night or in bad weather.
Solar vs mains-powered pump
| Solar pump | Mains (AC) submersible | |
|---|---|---|
| Running cost | None | Electricity, depending on hours run |
| Power cuts | Keeps working in daylight | Stops unless on an inverter or generator |
| Upfront cost | Higher (panels + controller) | Lower |
| Night-time water | From the storage tank | Direct, any time |
| Best for | Gardens, smallholdings, livestock, anyone with a storage tank | High flow on demand, small sites with no space for panels |
Sizing it properly
The installer needs:
- Daily water need: house, garden and animals. See boreholes on smallholdings.
- Borehole yield and depth, from the original yield test. The pump must not pump faster than the borehole can recover.
- Total head: the height from the water level up to the top of the tank.
- Storage: enough for at least a day or two of cloudy weather.
Questions to ask an installer
- Which pump and controller brands, and what warranty does each have?
- Does it have dry-run protection and a tank float switch?
- How are the panels mounted and protected against theft?
- Is it hybrid-ready, so it can run off mains or an inverter later?
For pump replacement or conversion, see borehole pump installation and repair, and for a new borehole, borehole drilling costs in Benoni.