Solar Powered Water Pumps in Kenya: sizing, applications and benefits

Solar water pumping involves extracting water from a source (well, pond, river, storage tank, etc.) using the sun’s energy.

Common applications are water for dairy farming, crop irrigation, drinking, and cooking water supply. Solar water pumping can also be used for community projects. Institutions and water supply for remote areas that do not have access to grid electricity. One of the biggest advantages of solar water pumping in Kenya is that it has no electricity bills or fuel costs.

Solar Powered Water Pumps in Kenya use the sun to generate electricity to pump water.

Solar Powered Water Pump Applications

During hot months and in hot areas the requirement for water is high. Private households and farms need a stable and consistent water supply. Solar water pumps are electrically driven pumping systems, powered by photovoltaic solar panels. Solar water pumps use the generated electricity to pump water. According to each individual need, solar water pumps in Kenya can be applied for the following purposes where pumping water is needed:

Water for dairy farming
Water for crop irrigation
Drinking and cooking water supply

Solar Powered Water Pump systems are fairly basic installations and can be quickly setup by most solar power companies in Kenya like Jesaton Systems

Sizing of the pump

Correct sizing of the pump and controlling devices is important, as this determines the amount of water that can be pumped from the borehole or reservoir. The sizing of the Solar Powered Water Pump needs to be done according to the location and projected usage of the system.

The sizing of the pump will take into consideration the depth of the water source, amount of water required on a daily basis and the amount of sunlight in the area.

You might want to ask yourself the following questions to design the solar pumping system that will meet your needs and fit into your budget:

What quantity of water do I need every day?
When do I need water?
What water flow/pressure do I need?
How many meters must I lift the water from the source to the head of the storage tank? (this is the total dynamic head elevation)
What is the capacity of my storage tank?
What is the quality of my water (could it damage the pump?)

What components are used for Solar Powered Water Pump installations?

A solar water pump installation is a fairly basic system and typically consists of a water pump (submersible or surface pump), solar panels, pipes and by extension water storage tank. Most solar water pump systems don’t use batteries.

Selecting the solar water pump

You should be aware that different water pumps are used for different applications: Usually, the water level will determine which pump to use. Different types of water pumps can be selected to be used in streams, wells, or in ponds. We can divide water pumps into two types:

Submersible water pumps can be used to lift water from great depths of up to 700feet deep.
Surface water pumps can be used to pump surface water of 10-20 feet deep.

Selecting the solar panels

The best way to select the right components is to review the amount of water required per day. Based on the number of liters required per day, one can select the right water pump and then see the total power required that needs to be produced by the solar panels. The pump manufacturer will provide information on the number of watts that are required to produce the desired water flow.

After selecting the size and type of the solar pump, use the available information to calculate the watts of the solar panels. To increase the pumping volume and time, the solar panels can be installed on trackers. With the use of solar trackers the output can increase with up to 30%.

Here a complete overview of components for a typical Solar Powered Water Pump system:

Should I use batteries?

A solar water pump does not necessarily require batteries. To save costs, the majority of solar powered water pumps can run directly from the solar panels. Electricity aimed at running the water pump is not stored in batteries, but the water is instead stored in a water tank or pond. This way the water is stored and can be used anytime required.

Benefits of solar powered water pumps

Solar water pump installations in Kenya are versatile and can be used for various applications: It enables people to manage their drinking water supply, livestock watering, irrigation, and other residential applications. Usually, the need for water is greatest during the hot sunny days. During these peak times, the PV panels also produce the most power and most water will be pumped into the storage tank. Due to the simplicity of solar powered water pump systems, this technology is reliable, and requires little maintenance.