The availability of water is a prime factor for agriculture. Many farmers in our country depend on borewells for irrigation. They need pumps to lift water from those borewells. As electricity may not be easily available in some rural areas, a solar pump is the best solution for borewell owners. However, they need to know some facts about the use of solar pumps to lift water from deep borewells. They should check the depth capabilities of solar pumps before installing them beside borewells. Unnati Pump offers a range of solar pumps for the customers. Selecting the right solar pump ensures the water supply at the required speed without damaging the pump motor.
How Solar Pumps Function To Lift Water from Borewells
A solar pump utilizes solar energy that is generated by solar panels. These panels convert sunlight into electricity, which is transferred to the solar pump motor. The pump then operates to lift water from borewells. The following factors are responsible for lifting water from borewells using a solar pump –
- Type of the solar pump
- Depth of the borewell
- Power supplied to the pump motor
- Static and dynamic levels of the water
- Capacity of the solar panels
- Design of the pumping system
- Diameter of the pipes carrying water
The solar power needed to lift water is directly dependent on the depth of the water level in the borewell.
Difference between Static Water Level and Dynamic Water Level
A borewell owner should have an idea about two vital terms – static water level and dynamic water level.
Static water level – This is the natural depth of the water in the borewell before the pump starts operating. It is the normal underground water level of a place.
Dynamic water level – This is the depth of water in the borewell after switching on the solar pump. It is much deeper than the static water level because some water has already been drawn out by using the pump.
The knowledge of the dynamic water level is more important while choosing a solar pump because it shows the actual working condition of a borewell.
Two Main Varieties of Solar Pumps and Their Depth Capabilities
Different types of solar pumps are designed to operate in various depths. So, borewell owners need to know about these solar pumps and their applications.
1. Surface solar pumps
These solar pumps are installed above the ground and used for shallow water sources. The depth capability of a surface solar pump may extend up to 7 – 8 meters, making it suitable for shallow wells, ponds, and water tanks. Thus, it is most suitable for using in small farms, open wells, and to transfer water from one place to another. However, it is not suitable for use in borewells because its operation is based on the suction of water up to the mentioned depths.
2. Submersible solar pumps
These solar pumps are used for drawing water from borewells. A submersible solar pump can be installed inside a borewell. The pump motor pushes water upwards instead of pulling it. Hence, the depth capability of this pump ranges from 20 meters to 200 meters, making it suitable for all borewells. Some high-capacity pumping systems can work efficiently even at depths of more than 300 meters. Apart from borewells, this pump is also used for supplying drinking water in rural areas.
Requirements of Power for Lifting Water from Deep Borewells
Borewell owners should check the Horsepower (HP) rating of a solar pump before buying it. This rating shows the maximum depth from which the pump can lift water.
- 1 HP solar pump – Works up to 30 – 50 meters
- 2 HP solar pump – Works up to 70 – 100 meters
- 3 HP solar pump – Works up to 120 – 150 meters
- 5 HP solar pump – Works up to 180 – 220 meters
- 7.5 HP and above – Works up to 250 – 300 meters or more
These approximate values may vary according to the design of the pumping system, the demand for water, and solar conditions.
Solar pumps with higher horsepower need larger solar panels, which enhances the overall pumping system capacity and the water lifting capability.
Importance of the Capacity of Solar Panels
Solar panels supply power to the pump motor. So, the performance of the pump directly depends on the capacity of solar panels. If the depth of the borewell is greater, larger solar panels are needed to ensure smooth performance of the solar pump. If the capacity of solar panels is not enough, the working speed of the pump will decrease, and the water output will also reduce to a certain extent.
The Key Measurement of the Total Dynamic Head (TDH)
Usually, engineers discuss TDH while speaking about how deep a solar pump can lift water. TDH is the short form of Total Dynamic Head that represents the total resistance a solar pump must overcome to lift water. It includes the vertical lifting height, losses caused by pipe friction, the requirement of the water pressure, and the height of the water discharge point. In simple words, TDH is the addition of water level, tank height, and pipe losses.
Influence of the Borewell Diameter
The diameter of the borewell is an important factor that affects the performance of a solar pump. Generally, the diameter of a borewell can be 4 inches, 6 inches, or 8 inches. If a borewell is narrow, it needs a slim solar submersible pump. On the other hand, a wide borewell can accommodate a solar pump of higher capacity. Hence, it is essential to choose a solar pump that fits perfectly in the borewell to ensure its smooth operation.
Conclusion
Therefore, borewell owners need to keep several factors in mind while choosing a solar pump. They need to measure the depth of the borewell, determine the water levels, have an estimate of the daily water demand, and assess the average hours of sunlight availability in their region every day. They can consult an expert engineer to get more insight into this matter. Choosing a trusted solution like Unnati Pumps can further help ensure efficiency, durability, and reliable operation for different irrigation needs.