Solar pump improves crop irrigation in Africa

A farming community in Africa is now able to irrigate its crops on a reliable year-round basis, thanks to a solar pumping solution from NOV Mono. The Sun-Sub submersible pump system is located on the banks of the Mereb River in Eritrea, where the community now has greatly improved access to water.

“Severe shortages of diesel, and very high prices, mean that conventional pumps are often not an option for irrigation water duties in places like Eritrea,” said Mono’s Maurice Calderon. “However, Mono has a very successful track record of providing solar pumps for this type of application.”

Available with either a stationary or GPS tracking array, and with solar panel options ranging from 150 up to 2400 W, the submersible pump can produce very high flows and discharge pressures. It requires no external diesel or electrical power supply, and can easily be configured for automatic operation by the use of float switches, a pressure kit or a built-in electronic control. This allows the product to turn on when water is required and off once any storage vessels are full, thereby conserving water and reducing wear on the pump.

Working with the team at Visual Direct International, a provider of energy management products and systems, the pumping system was fitted with a stationary array. This enables it to draw some 100 m³ of water per day from the 7.3 m deep well and pump it over 228 m to a concrete surface reservoir. This can hold up to four days’ supply, ensuring that the farmers always have water to irrigate their citrus trees.

“We help farmers cut their costs, and make a reliable source of water a practical and affordable option,” said Calderon. “This helps them increase production and also generate new sources of income by planting new crops that were not previously viable.”

With speeds of 1800-2400 rpm, the progressing cavity pump provides maximum water output, even in bores containing silt or iron oxide. It delivers water with every rotation, while its low speed capability extends rotor and stator life in abrasive bores.

All Sun-Sub systems are supplied complete with pre-wired solar modules, array frames, a pump element, submersible motor and solar motor controller, making them easy to assemble and install. With all electrical plugs and sockets pre-fitted, no specialist electrical knowledge is required.