Borehole Solar Water Pump

How does a borehole solar water pump work?

By convering the sun’s rays (photons) to electricity that will power the motor, which runs the water pump . It uses solar panles to harvest the photons (units of light) from sunlight, producing the direct current (DC) that provides the eneygy for the motor to drive the pump to extract water from its source

What do I need to run a water pump on solar?

1. Solar panels
2. Cabling
3. An inverter if the pump uses AC power, or if you want the pump to run on AC when sunlight is unavailable
4. A control panel

How do you install a solar borehole pump?

See the process in a video towards the end of this article

Borehole submersible water pump installation in a shallow well by hand

What are the advantages of a borehole solar water pump?

• There are no perational costs such as monthly power bills
• It is easy to maintain as it does not require regular servicing
• It is tailored to the borehole’s parameters

What are the disdvantages of a borehole solar water pump?

• It is expensive to install
• It requires expertise to install

A deep well solar borehole water pump under installation by Grekkon Limited in Malaa area, Machakos county

Borehole solar water pump cost in Kenya

Our borehole solar water pump prices in Kenya range from Kes 38,000, to Kes Kes 2,500,000 depending on the borehole depth and yield. This borehole pump price also a factor of the submersible water pump type; electric or solar, and the specifications of each model. The cost of installing a borehole is provided when procuring the water pump

Borehole solar water pump cost

How to select the best borehole pumps

1. Pump head

This is the maximum height the submersible water pump will push water against gravity. It is in meters, and defines the water pump’s pressure rating. For instance if the pump reads 90M head, then it will push fluid vertically to a maximum of 90M

The distance from the highest point of the water pipe to the depth of the water pump is the head

2. Discharge rate or flow rate

This is the amount of water that the water pump will do per given time- usually given in hours. This will be to the borehole’s test pumping report recommendation which provides the recharge rate of the borehole. If the water pump’s discharge rate at that depth is lower than the test pumping report recommendation, then the user receives less water. If the water pump’s rate is higher, then they run the risk of pumping the borehole dry

A graph illustrating the inverse relationship between flow rate and head for a specific submersible water pump. The higher the head, the lower the flow rate and vice versa

3. Mode of power

The borehole pump price for a submersible electric, a solar water pump or a hybrid of both is different. Solar water pumps have a high initial purchase and installation cost, and near zero running costs. This is because of support accessories such as the solar panels, the solar panels support structure, and the inverter. They are great in off-grid electricity locations. Electric submersible pumps are cheaper to buy and install, but incur monthly electricity charges. There are hybrid submersible water pumps from manufacturers. An inverter will convert an electric or solar water pump to a  hybrid water pump. Electric submersible borehole water pumps have either a single or three phase motor according to the pump size

This is to allow switching to either mode. A hybrid water pump will use solar power on a sunny day, and  electricity when the sun is absent. They will be in on-grid electricity locations. Your choice of water pump will there for depend on your budget, and location; is it an on or off-grid electricity area?

Both the electric and solar submersible water pumps have the same lifespan, which is in decades. Borehole solar water pump prices in Kenya depend on the

4. Motor size

Each submersible water pump has a motor which powers the water pump. in kilowatts (kW) or horsepower (Hp). The larger it is, the bigger the pump and vice versa which determines the specific borehole water pump cost

An illustration of the position of the motor on a borehole water pump

Steps to choosing a solar panel to run a water pump

•  Understand the motor power rating in kW or Hp
• Multiply the kW by a factor 1.5 for poly-crystalline solar panels, and by 1.25 for mono-crystalline solar panels. This is to cater for power losses during transmission
• Check the solar panels that have the closest watts per panel. For example if the total required power is 12,000 watts, then divide this by a 545 watts panel. This gives 22 solar panels. If it is a small pump powered by 300 watts, then 1 panel of 300 watts is sufficient

We have various types of solar water pumps for boreholes; from shallow to deep wells. These borehole solar water pumps in Kenya are available in our offices countrywide

Borehole Solar Water Pump FAQs

I. How do you size a borehole pump?

Your borehole test pumping results provide you with the static water level, the dynamic head, and the recharge rate of the borehole. When we factor in your pumping height, then we arrive at the right sized borehole water pump

A sample test pumping report                                                                                                                                                               

II. Which is the best borehole solar water pump?

One that meets your pressure and water volume needs, and runs on a stainless steel, not plastic motor

III. How long can a borehole pump run continously?

An ordinary borehole should ideally run for 7 to 8 hours in a day. Running for pro-longed periods frequently will damage the motor, and if you’re using electricity, your electric bills will soar

IV. What type of pump is used for boreholes?

An electric submersible or solar  powered submersible water pump. They are centrifugal pumps driven by a submersible stainless steel motor. The water pumps must always remain submerged during operation

V. How long should a borehole pump last?

Our correctly installed, stainless steel borehole water pumps last for many decades in use with timely servicing, and proper usage

VI. How many solar panels do I need to run a solar pump?

This depends on the Hp or kW rating of the solar water pump’s motor

VII. How many solar panels do I need to run a 1HP water pump?

Step 1. Conver 1HP to Kilowatts as; 1Hp = 0.7355kW

Step 2. Covert kW to Watts. 0.7355 x 1,000 = 735.5 watts

Step 3. cater for power loss by multiplying 735.watts x 1.5 = 1,103.25 watts. The total power needed is 1,103 watts to run a 1Hp water pump

Step 4. Determine the number of solar panels. Divide the total watts by the number of watts per panel. For example, if the solar panel has 530 watts, then the total number of panles is 1,103 watts/530 watts= 2  panels

VIII. How deep can a solar pump pump water?

The depth depends on the head of the solar pump. The larger it is, the greater the depth that the solar pump will work from