Q. With reference to solar water pumps, consider the following statements:
- Solar power can be used for running surface pumps and not for submersible pumps.
- Solar power can be used for running centrifugal pumps and not the ones with piston.
Which of the statements given above is/are correct?
- 1 only
- 2 only
- Both 1 and 2
- Neither 1 nor 2
Answer: (d) Neither 1 nor 2
Solar water pumps
- Solar water pumps are specially designed to utilize DC electric power from photovoltaic modules. The pumps must work during low light conditions, when power is reduced, without stalling or overheating. Low volume pumps use positive displacement (volumetric) mechanisms which seal water in cavities and force it upward. Lift capacity is maintained even while pumping slowly. These mechanisms include diaphragm, vane and piston pumps. These differ from a conventional centrifugal pump that needs to spin fast to work efficiently. Centrifugal pumps are used where higher volumes are required.
- A surface pump is one that is mounted at ground level. Surface pumps work well when they draw water through suction less than 10 or 20 feet. A submersible pump is one that is lowered into the water. Most deep wells use submersible pumps. And both are compatible with the photovoltaic array (For Solar power).
- The most common pump mechanics in Solar power pumps used are centrifugal pumps, multistage pumps, borehole pumps, and helical pumps.
- A solar water pump system is commonly seen in residential and commercial uses, as well as for irrigation of agricultural land.
- Through solar panels, the pump can eliminate the cost of energy and provide a more feasible option that uses energy from the sun.
- When it comes to stand-alone solar pumping systems, the main types include rotating and positive displacement pumps.
- Centrifugal pumps are the common choice for rotation and are designed for fixed head applications.
- Their output increases in proportion to their speed of rotation.