Hybrid AC/DC solar borehole pump solutions

What is an AC/DC solar borehole pump?

A hybrid AC/DC solar borehole pump is designed to deliver water 24 hours a day, as it it runs on both DC power - from solar panels or batteries, and AC power - from a power grid or a generator. A hybrid borehole pump system offers a perfect water supply solution in remote areas where water is scarce and the power supply is unreliable or non-existent. Thanks to load shedding and irregular municipal water supplies, solar borehole pumps are increasingly used for irrigation purposes in residential estates and upmarket properties in South Africa.

How does the solar pump system work?

On a sunny day, the PV array converts the solar energy into power at a DC voltage, which is used for running the motor pump set. The system requires a sunny, shadow-free area for installation of the solar panels. When the power from the solar panels becomes insufficient from lack of sunlight, the system switches to the AC power source via a power controller. If the AC power source is a generator, the controller automatically switches the generator on.

Recommended hybrid solar borehole pumps

The LEO LPS Series

4LPS leo pumps solar borehole pump
LEO 4SR3-5 Hybrid AC/DC Solar Submersible Borehole Pump Kit, 3000l/h @ 50m Depth

The Leo Pumps 4LPS is a unique series of hybrid solar borehole pumps that have the ability to deliver water 24 hours a day, as they run on both DC and AC power. These pumps allow you to save money during the day time, which eventually will pay for itself in the long run. They will switch over to regular AC power, seamlessly, when it is over-cast or when the sun goes down, which a regular borehole pump cannot do. Advantage of this - constant water delivery, no interruptions due to the weather, and no limitations to time of day operating.

The 4LPS pumps can handle single phase or three phase AC power (depending on the model), and 60 to 410V DC power.

The pump motor includes intelligent dry-run protection: When the water level is lower than the pump inlet, the system automatically stops running. After 20-30 seconds, it will start to detect again. If the water-free state is detected by more than 4 times, it will enter the 30-minute long-term protection state condition. The pump motor also includes over-voltage protection, over-current and over-load protection.

The 4LPS pumps rely on a variable speed drive (VSD) motor to guarantee constant water flow at a given depth.

What size solar panels are needed?

The motor can be used on any size borehole from 0.37 - 2.2kW, with different amounts of solar panels. A 0.37kW 4LPS pump would require 2 x 300W solar panels. A 2.2kW 4LPS pump would require an array of solar panels of 3000W. 

This hybrid borehole solution is not only suitable for farms, but also for residential properties that rely on a borehole and are affected by Load Shedding!

Learn more about various borehole pumps solutions | ft Leo Pumps

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